An odd fix for GCC 7

Summary: Update HISTORY.md for release 3.3

Test Plan: n/a

Reviewers: sdong, ljin, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19635

.arcconfig

@@ -1,9 +1,9 @@
 {
-  "project_id" : "leveldb",
+  "project_id" : "rocksdb",
   "conduit_uri" : "https://reviews.facebook.net/",
-  "copyright_holder" : "",
+  "copyright_holder" : "Facebook",
   "load" : [
-    "linters/src/"
+    "linters"
   ],
   "lint.engine" : "FacebookFbcodeLintEngine",
   "lint.engine.single.linter" : "FbcodeCppLinter"

.clang-format

@@ -0,0 +1,5 @@
+# Complete list of style options can be found at: 
+# http://clang.llvm.org/docs/ClangFormatStyleOptions.html
+---
+BasedOnStyle: Google
+...

.gitignore

@@ -1,4 +1,6 @@
+TARGETS
 build_config.mk
+
 *.a
 *.arc
 *.d
@@ -9,16 +11,24 @@ build_config.mk
 *.so
 *.so.*
 *_test
-db_bench
-db_repl_stress
-db_stress
+*_bench
+*_stress
+*.out
+*.class
+*.jar
+*.*jnilib*
+*.d-e
+*.o-*
+*.swp
+
 ldb
-leveldb_server
-leveldb_shell
 manifest_dump
 sst_dump
 util/build_version.cc
 build_tools/VALGRIND_LOGS/
 coverage/COVERAGE_REPORT
-util/build_version.cc.tmp
 .gdbhistory
+.phutil_module_cache
+tags
+java/*.log
+java/include/org_rocksdb_*.h

.travis.yml

@@ -0,0 +1,20 @@
+language: cpp
+compiler: gcc
+before_install:
+# As of this writing (10 May 2014) the Travis build environment is Ubuntu 12.04,
+# which needs the following ugly dependency incantations to build RocksDB:
+ - sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test
+ - sudo apt-get update -qq
+ - sudo apt-get install -y -qq gcc-4.8 g++-4.8 zlib1g-dev libbz2-dev libsnappy-dev libjemalloc-dev
+ - sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.8 50
+ - sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.8 50
+ - wget https://gflags.googlecode.com/files/libgflags0_2.0-1_amd64.deb
+ - sudo dpkg -i libgflags0_2.0-1_amd64.deb
+ - wget https://gflags.googlecode.com/files/libgflags-dev_2.0-1_amd64.deb
+ - sudo dpkg -i libgflags-dev_2.0-1_amd64.deb
+# Lousy hack to disable use and testing of fallocate, which doesn't behave quite
+# as EnvPosixTest::AllocateTest expects within the Travis OpenVZ environment.
+ - sed -i "s/fallocate(/HACK_NO_fallocate(/" build_tools/build_detect_platform
+script: make check -j8
+notifications:
+    email: false

CONTRIBUTING.md

@@ -0,0 +1,19 @@
+# Contributing to RocksDB
+
+## Contributor License Agreement ("CLA")
+
+In order to accept your pull request, we need you to submit a CLA. You
+only need to do this once, so if you've done this for another Facebook
+open source project, you're good to go. If you are submitting a pull
+request for the first time, just let us know that you have completed
+the CLA and we can cross-check with your GitHub username.
+
+Complete your CLA here: <https://code.facebook.com/cla>
+
+If you prefer to sign a paper copy, we can send you a PDF.  Send us an 
+e-mail or create a new github issue to request the CLA in PDF format.
+
+## License
+
+By contributing to RocksDB, you agree that your contributions will be
+licensed under the [BSD License](LICENSE).

HISTORY.md

@@ -0,0 +1,118 @@
+# Rocksdb Change Log
+
+## 3.3.0 (7/10/2014)
+### New Features
+* Added JSON API prototype.
+* HashLinklist reduces performance outlier caused by skewed bucket by switching data in the bucket from linked list to skip list. Add parameter threshold_use_skiplist in NewHashLinkListRepFactory().
+* RocksDB is now able to reclaim storage space more effectively during the compaction process.  This is done by compensating the size of each deletion entry by the 2X average value size, which makes compaction to be triggerred by deletion entries more easily.
+* Add TimeOut API to write.  Now WriteOptions have a variable called timeout_hint_us.  With timeout_hint_us set to non-zero, any write associated with this timeout_hint_us may be aborted when it runs longer than the specified timeout_hint_us, and it is guaranteed that any write completes earlier than the specified time-out will not be aborted due to the time-out condition.
+* Add a rate_limiter option, which controls total throughput of flush and compaction. The throughput is specified in bytes/sec. Flush always has precedence over compaction when available bandwidth is constrained.
+
+### Public API changes
+* Removed NewTotalOrderPlainTableFactory because it is not used and implemented semantically incorrect.
+
+## 3.2.0 (06/20/2014)
+
+### Public API changes
+* We removed seek compaction as a concept from RocksDB because:
+1) It makes more sense for spinning disk workloads, while RocksDB is primarily designed for flash and memory,
+2) It added some complexity to the important code-paths,
+3) None of our internal customers were really using it.
+Because of that, Options::disable_seek_compaction is now obsolete. It is still a parameter in Options, so it does not break the build, but it does not have any effect. We plan to completely remove it at some point, so we ask users to please remove this option from your code base.
+* Add two paramters to NewHashLinkListRepFactory() for logging on too many entries in a hash bucket when flushing.
+* Added new option BlockBasedTableOptions::hash_index_allow_collision. When enabled, prefix hash index for block-based table will not store prefix and allow hash collision, reducing memory consumption.
+
+### New Features
+* PlainTable now supports a new key encoding: for keys of the same prefix, the prefix is only written once. It can be enabled through encoding_type paramter of NewPlainTableFactory()
+* Add AdaptiveTableFactory, which is used to convert from a DB of PlainTable to BlockBasedTabe, or vise versa. It can be created using NewAdaptiveTableFactory()
+
+### Performance Improvements
+* Tailing Iterator re-implemeted with ForwardIterator + Cascading Search Hint , see ~20% throughput improvement.
+
+## 3.1.0 (05/21/2014)
+
+### Public API changes
+* Replaced ColumnFamilyOptions::table_properties_collectors with ColumnFamilyOptions::table_properties_collector_factories
+
+### New Features
+* Hash index for block-based table will be materialized and reconstructed more efficiently. Previously hash index is constructed by scanning the whole table during every table open.
+* FIFO compaction style
+
+## 3.0.0 (05/05/2014)
+
+### Public API changes
+* Added _LEVEL to all InfoLogLevel enums
+* Deprecated ReadOptions.prefix and ReadOptions.prefix_seek. Seek() defaults to prefix-based seek when Options.prefix_extractor is supplied. More detail is documented in https://github.com/facebook/rocksdb/wiki/Prefix-Seek-API-Changes
+* MemTableRepFactory::CreateMemTableRep() takes info logger as an extra parameter.
+
+### New Features
+* Column family support
+* Added an option to use different checksum functions in BlockBasedTableOptions
+* Added ApplyToAllCacheEntries() function to Cache
+
+## 2.8.0 (04/04/2014)
+
+* Removed arena.h from public header files.
+* By default, checksums are verified on every read from database
+* Change default value of several options, including: paranoid_checks=true, max_open_files=5000, level0_slowdown_writes_trigger=20, level0_stop_writes_trigger=24, disable_seek_compaction=true, max_background_flushes=1 and allow_mmap_writes=false
+* Added is_manual_compaction to CompactionFilter::Context
+* Added "virtual void WaitForJoin()" in class Env. Default operation is no-op.
+* Removed BackupEngine::DeleteBackupsNewerThan() function
+* Added new option -- verify_checksums_in_compaction
+* Changed Options.prefix_extractor from raw pointer to shared_ptr (take ownership)
+  Changed HashSkipListRepFactory and HashLinkListRepFactory constructor to not take SliceTransform object (use Options.prefix_extractor implicitly)
+* Added Env::GetThreadPoolQueueLen(), which returns the waiting queue length of thread pools
+* Added a command "checkconsistency" in ldb tool, which checks
+  if file system state matches DB state (file existence and file sizes)
+* Separate options related to block based table to a new struct BlockBasedTableOptions.
+* WriteBatch has a new function Count() to return total size in the batch, and Data() now returns a reference instead of a copy
+* Add more counters to perf context.
+* Supports several more DB properties: compaction-pending, background-errors and cur-size-active-mem-table.
+
+### New Features
+* If we find one truncated record at the end of the MANIFEST or WAL files,
+  we will ignore it. We assume that writers of these records were interrupted
+  and that we can safely ignore it.
+* A new SST format "PlainTable" is added, which is optimized for memory-only workloads. It can be created through NewPlainTableFactory() or NewTotalOrderPlainTableFactory().
+* A new mem table implementation hash linked list optimizing for the case that there are only few keys for each prefix, which can be created through NewHashLinkListRepFactory().
+* Merge operator supports a new function PartialMergeMulti() to allow users to do partial merges against multiple operands.
+* Now compaction filter has a V2 interface. It buffers the kv-pairs sharing the same key prefix, process them in batches, and return the batched results back to DB. The new interface uses a new structure CompactionFilterContext for the same purpose as CompactionFilter::Context in V1.
+* Geo-spatial support for locations and radial-search.
+
+## 2.7.0 (01/28/2014)
+
+### Public API changes
+
+* Renamed `StackableDB::GetRawDB()` to `StackableDB::GetBaseDB()`.
+* Renamed `WriteBatch::Data()` `const std::string& Data() const`.
+* Renamed class `TableStats` to `TableProperties`.
+* Deleted class `PrefixHashRepFactory`. Please use `NewHashSkipListRepFactory()` instead.
+* Supported multi-threaded `EnableFileDeletions()` and `DisableFileDeletions()`.
+* Added `DB::GetOptions()`.
+* Added `DB::GetDbIdentity()`.
+
+### New Features
+
+* Added [BackupableDB](https://github.com/facebook/rocksdb/wiki/How-to-backup-RocksDB%3F)
+* Implemented [TailingIterator](https://github.com/facebook/rocksdb/wiki/Tailing-Iterator), a special type of iterator that
+  doesn't create a snapshot (can be used to read newly inserted data)
+  and is optimized for doing sequential reads.
+* Added property block for table, which allows (1) a table to store
+  its metadata and (2) end user to collect and store properties they
+  are interested in.
+* Enabled caching index and filter block in block cache (turned off by default).
+* Supported error report when doing manual compaction.
+* Supported additional Linux platform flavors and Mac OS.
+* Put with `SliceParts` - Variant of `Put()` that gathers output like `writev(2)`
+* Bug fixes and code refactor for compatibility with upcoming Column
+  Family feature.
+
+### Performance Improvements
+
+* Huge benchmark performance improvements by multiple efforts. For example, increase in readonly QPS from about 530k in 2.6 release to 1.1 million in 2.7 [1]
+* Speeding up a way RocksDB deleted obsolete files - no longer listing the whole directory under a lock -- decrease in p99
+* Use raw pointer instead of shared pointer for statistics: [5b825d](https://github.com/facebook/rocksdb/commit/5b825d6964e26ec3b4bb6faa708ebb1787f1d7bd) -- huge increase in performance -- shared pointers are slow
+* Optimized locking for `Get()` -- [1fdb3f](https://github.com/facebook/rocksdb/commit/1fdb3f7dc60e96394e3e5b69a46ede5d67fb976c) -- 1.5x QPS increase for some workloads
+* Cache speedup - [e8d40c3](https://github.com/facebook/rocksdb/commit/e8d40c31b3cca0c3e1ae9abe9b9003b1288026a9)
+* Implemented autovector, which allocates first N elements on stack. Most of vectors in RocksDB are small. Also, we never want to allocate heap objects while holding a mutex. -- [c01676e4](https://github.com/facebook/rocksdb/commit/c01676e46d3be08c3c140361ef1f5884f47d3b3c)
+* Lots of efforts to move malloc, memcpy and IO outside of locks

INSTALL.md

@@ -0,0 +1,84 @@
+## Compilation
+
+RocksDB's library should be able to compile without any dependency installed,
+although we recommend installing some compression libraries (see below).
+We do depend on newer gcc with C++11 support.
+
+There are few options when compiling RocksDB:
+
+* [recommended] `make static_lib` will compile librocksdb.a, RocksDB static library.
+
+* `make shared_lib` will compile librocksdb.so, RocksDB shared library.
+
+* `make check` will compile and run all the unit tests
+
+* `make all` will compile our static library, and all our tools and unit tests. Our tools
+depend on gflags. You will need to have gflags installed to run `make all`.
+
+## Dependencies
+
+* You can link RocksDB with following compression libraries:
+  - [zlib](http://www.zlib.net/) - a library for data compression.
+  - [bzip2](http://www.bzip.org/) - a library for data compression.
+  - [snappy](https://code.google.com/p/snappy/) - a library for fast
+      data compression.
+
+* All our tools depend on:
+  - [gflags](https://code.google.com/p/gflags/) - a library that handles
+      command line flags processing. You can compile rocksdb library even
+      if you don't have gflags installed.
+
+## Supported platforms
+
+* **Linux - Ubuntu**
+    * Upgrade your gcc to version at least 4.7 to get C++11 support.
+    * Install gflags. First, try: `sudo apt-get install libgflags-dev`
+      If this doesn't work and you're using Ubuntu, here's a nice tutorial:
+      (http://askubuntu.com/questions/312173/installing-gflags-12-04)
+    * Install snappy. This is usually as easy as:
+      `sudo apt-get install libsnappy-dev`.
+    * Install zlib. Try: `sudo apt-get install zlib1g-dev`.
+    * Install bzip2: `sudo apt-get install libbz2-dev`.
+* **Linux - CentOS**
+    * Upgrade your gcc to version at least 4.7 to get C++11 support:
+      `yum install gcc47-c++`
+    * Install gflags:
+
+              wget https://gflags.googlecode.com/files/gflags-2.0-no-svn-files.tar.gz
+              tar -xzvf gflags-2.0-no-svn-files.tar.gz
+              cd gflags-2.0
+              ./configure && make && sudo make install
+
+    * Install snappy:
+
+              wget https://snappy.googlecode.com/files/snappy-1.1.1.tar.gz
+              tar -xzvf snappy-1.1.1.tar.gz
+              cd snappy-1.1.1
+              ./configure && make && sudo make install
+
+    * Install zlib:
+
+              sudo yum install zlib
+              sudo yum install zlib-devel
+
+    * Install bzip2:
+
+              sudo yum install bzip2
+              sudo yum install bzip2-devel
+
+* **OS X**:
+    * Install latest C++ compiler that supports C++ 11:
+        * Update XCode:  run `xcode-select --install` (or install it from XCode App's settting).
+        * Install via [homebrew](http://brew.sh/).
+            * If you're first time developer in MacOS, you still need to run: `xcode-select --install` in your command line.
+            * run `brew tap homebrew/dupes; brew install gcc47 --use-llvm` to install gcc 4.7 (or higher).
+    * Install zlib, bzip2 and snappy libraries for compression.
+    * Install gflags. We have included a script
+    `build_tools/mac-install-gflags.sh`, which should automatically install it (execute this file instead of runing using "source" command).
+    If you installed gflags by other means (for example, `brew install gflags`),
+    please set `LIBRARY_PATH` and `CPATH` accordingly.
+    * Please note that some of the optimizations/features are disabled in OSX.
+    We did not run any production workloads on it.
+
+* **iOS**:
+  * Run: `TARGET_OS=IOS make static_lib`

LICENSE

@@ -1,3 +1,11 @@
+BSD License
+
+For rocksdb software
+
+Copyright (c) 2014, Facebook, Inc.
+All rights reserved.
+---------------------------------------------------------------------
+
 Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 
 Redistribution and use in source and binary forms, with or without

Makefile

@@ -6,21 +6,51 @@
 INSTALL_PATH ?= $(CURDIR)
 
 #-----------------------------------------------
-# Uncomment exactly one of the lines labelled (A), (B), and (C) below
-# to switch between compilation modes.
 
-# OPT ?= -DNDEBUG     # (A) Production use (optimized mode)
+ifneq ($(MAKECMDGOALS),dbg)
 OPT += -O2 -fno-omit-frame-pointer -momit-leaf-frame-pointer
+else
+# intentionally left blank
+endif
+
+ifeq ($(MAKECMDGOALS),shared_lib)
+OPT += -DNDEBUG
+endif
+
+ifeq ($(MAKECMDGOALS),static_lib)
+OPT += -DNDEBUG
+endif
+
 #-----------------------------------------------
 
 # detect what platform we're building on
-$(shell (export ROCKSDB_ROOT=$(CURDIR); $(CURDIR)/build_tools/build_detect_platform $(CURDIR)/build_config.mk))
+$(shell (export ROCKSDB_ROOT="$(CURDIR)"; "$(CURDIR)/build_tools/build_detect_platform" "$(CURDIR)/build_config.mk"))
 # this file is generated by the previous line to set build flags and sources
 include build_config.mk
 
-WARNING_FLAGS = -Wall -Werror
-CFLAGS += -g $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CCFLAGS) $(OPT)
-CXXFLAGS += -g $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CXXFLAGS) $(OPT) -std=gnu++0x -Woverloaded-virtual
+ifneq ($(PLATFORM), IOS)
+CFLAGS += -g
+CXXFLAGS += -g
+else
+# no debug info for IOS, that will make our library big
+OPT += -DNDEBUG
+endif
+
+# ASAN doesn't work well with jemalloc. If we're compiling with ASAN, we should use regular malloc.
+ifdef COMPILE_WITH_ASAN
+	# ASAN compile flags
+	EXEC_LDFLAGS += -fsanitize=address
+	PLATFORM_CCFLAGS += -fsanitize=address
+	PLATFORM_CXXFLAGS += -fsanitize=address
+else
+	# if we're not compiling with ASAN, use jemalloc
+	EXEC_LDFLAGS := $(JEMALLOC_LIB) $(EXEC_LDFLAGS)
+	PLATFORM_CXXFLAGS += $(JEMALLOC_INCLUDE) -DHAVE_JEMALLOC
+	PLATFORM_CCFLAGS += $(JEMALLOC_INCLUDE) -DHAVE_JEMALLOC
+endif
+
+CFLAGS += $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CCFLAGS) $(OPT)
+CXXFLAGS += $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CXXFLAGS) $(OPT) -Woverloaded-virtual
 
 LDFLAGS += $(PLATFORM_LDFLAGS)
 
@@ -30,24 +60,32 @@ MEMENVOBJECTS = $(MEMENV_SOURCES:.cc=.o)
 
 TESTUTIL = ./util/testutil.o
 TESTHARNESS = ./util/testharness.o $(TESTUTIL)
+BENCHHARNESS = ./util/benchharness.o
 VALGRIND_ERROR = 2
 VALGRIND_DIR = build_tools/VALGRIND_LOGS
 VALGRIND_VER := $(join $(VALGRIND_VER),valgrind)
 VALGRIND_OPTS = --error-exitcode=$(VALGRIND_ERROR) --leak-check=full
 
 TESTS = \
+	db_test \
+	block_hash_index_test \
+	autovector_test \
+	column_family_test \
+	table_properties_collector_test \
 	arena_test \
 	auto_roll_logger_test \
+	benchharness_test \
 	block_test \
 	bloom_test \
+	dynamic_bloom_test \
 	c_test \
 	cache_test \
 	coding_test \
 	corruption_test \
 	crc32c_test \
-	db_test \
 	dbformat_test \
 	env_test \
+	blob_store_test \
 	filelock_test \
 	filename_test \
 	filter_block_test \
@@ -58,33 +96,48 @@ TESTS = \
 	merge_test \
 	redis_test \
 	reduce_levels_test \
+	plain_table_db_test \
+	prefix_test \
+	simple_table_db_test \
 	skiplist_test \
 	stringappend_test \
-	table_test \
 	ttl_test \
+	backupable_db_test \
+	document_db_test \
+	json_document_test \
 	version_edit_test \
 	version_set_test \
+	file_indexer_test \
 	write_batch_test\
-	deletefile_test
+	deletefile_test \
+	table_test \
+	thread_local_test \
+        geodb_test \
+        rate_limiter_test
 
 TOOLS = \
         sst_dump \
+	db_sanity_test \
         db_stress \
         ldb \
-	db_repl_stress
+	db_repl_stress \
+	blob_store_bench
 
-PROGRAMS = db_bench signal_test $(TESTS) $(TOOLS)
-BENCHMARKS = db_bench_sqlite3 db_bench_tree_db
+PROGRAMS = db_bench signal_test table_reader_bench log_and_apply_bench $(TOOLS)
 
 # The library name is configurable since we are maintaining libraries of both
 # debug/release mode.
-LIBNAME = librocksdb
+ifeq ($(LIBNAME),)
+        LIBNAME=librocksdb
+endif
 LIBRARY = ${LIBNAME}.a
 MEMENVLIBRARY = libmemenv.a
 
 default: all
 
-# Should we build shared libraries?
+#-----------------------------------------------
+# Create platform independent shared libraries.
+#-----------------------------------------------
 ifneq ($(PLATFORM_SHARED_EXT),)
 
 ifneq ($(PLATFORM_SHARED_VERSIONED),true)
@@ -94,8 +147,8 @@ SHARED3 = $(SHARED1)
 SHARED = $(SHARED1)
 else
 # Update db.h if you change these.
-SHARED_MAJOR = 2
-SHARED_MINOR = 0
+SHARED_MAJOR = 3
+SHARED_MINOR = 3
 SHARED1 = ${LIBNAME}.$(PLATFORM_SHARED_EXT)
 SHARED2 = $(SHARED1).$(SHARED_MAJOR)
 SHARED3 = $(SHARED1).$(SHARED_MAJOR).$(SHARED_MINOR)
@@ -107,33 +160,42 @@ $(SHARED2): $(SHARED3)
 endif
 
 $(SHARED3):
-	$(CXX) $(LDFLAGS) $(PLATFORM_SHARED_LDFLAGS)$(SHARED2) $(CXXFLAGS) $(COVERAGEFLAGS) $(PLATFORM_SHARED_CFLAGS) $(SOURCES) -o $(SHARED3)
+	$(CXX) $(PLATFORM_SHARED_LDFLAGS)$(SHARED2) $(CXXFLAGS) $(PLATFORM_SHARED_CFLAGS) $(SOURCES) $(LDFLAGS) -o $@
 
 endif  # PLATFORM_SHARED_EXT
 
-all: $(SHARED) $(LIBRARY) $(PROGRAMS)
-
 .PHONY: blackbox_crash_test check clean coverage crash_test ldb_tests \
-	release tags valgrind_check whitebox_crash_test
+	release tags valgrind_check whitebox_crash_test format static_lib shared_lib all \
+	dbg
 
+all: $(LIBRARY) $(PROGRAMS) $(TESTS)
+
+static_lib: $(LIBRARY)
+
+shared_lib: $(SHARED)
+
+dbg: $(LIBRARY) $(PROGRAMS) $(TESTS)
+
+# creates static library and programs
 release:
 	$(MAKE) clean
-	OPT=-DNDEBUG $(MAKE) -j32
+	OPT="-DNDEBUG -O2" $(MAKE) static_lib $(PROGRAMS) -j32
 
 coverage:
 	$(MAKE) clean
-	COVERAGEFLAGS="-fprofile-arcs -ftest-coverage" LDFLAGS+="-lgcov" $(MAKE) all check
+	COVERAGEFLAGS="-fprofile-arcs -ftest-coverage" LDFLAGS+="-lgcov" $(MAKE) all check -j32
 	(cd coverage; ./coverage_test.sh)
 	# Delete intermediate files
-	find . -type f -regex ".*\.\(\(gcda\)\|\(gcno\)\)" | xargs --no-run-if-empty rm
+	find . -type f -regex ".*\.\(\(gcda\)\|\(gcno\)\)" -exec rm {} \;
 
-check: all $(PROGRAMS) $(TESTS) $(TOOLS) ldb_tests
+check: $(TESTS) ldb
 	for t in $(TESTS); do echo "***** Running $$t"; ./$$t || exit 1; done
-
-ldb_tests: all $(PROGRAMS) $(TOOLS)
 	python tools/ldb_test.py
 
-crash_test: blackbox_crash_test whitebox_crash_test
+ldb_tests: ldb
+	python tools/ldb_test.py
+
+crash_test: whitebox_crash_test blackbox_crash_test
 
 blackbox_crash_test: db_stress
 	python -u tools/db_crashtest.py
@@ -141,6 +203,16 @@ blackbox_crash_test: db_stress
 whitebox_crash_test: db_stress
 	python -u tools/db_crashtest2.py
 
+asan_check:
+	$(MAKE) clean
+	COMPILE_WITH_ASAN=1 $(MAKE) check -j32
+	$(MAKE) clean
+
+asan_crash_test:
+	$(MAKE) clean
+	COMPILE_WITH_ASAN=1 $(MAKE) crash_test
+	$(MAKE) clean
+
 valgrind_check: all $(PROGRAMS) $(TESTS)
 	mkdir -p $(VALGRIND_DIR)
 	echo TESTS THAT HAVE VALGRIND ERRORS > $(VALGRIND_DIR)/valgrind_failed_tests; \
@@ -156,14 +228,17 @@ valgrind_check: all $(PROGRAMS) $(TESTS)
 	done
 
 clean:
-	-rm -f $(PROGRAMS) $(BENCHMARKS) $(LIBRARY) $(SHARED) $(MEMENVLIBRARY) $(THRIFTSERVER) build_config.mk
+	-rm -f $(PROGRAMS) $(TESTS) $(LIBRARY) $(SHARED) $(MEMENVLIBRARY) build_config.mk
 	-rm -rf ios-x86/* ios-arm/*
-	-find . -name "*.[od]" | xargs --no-run-if-empty rm
-	-find . -type f -regex ".*\.\(\(gcda\)\|\(gcno\)\)" | xargs --no-run-if-empty rm
+	-find . -name "*.[od]" -exec rm {} \;
+	-find . -type f -regex ".*\.\(\(gcda\)\|\(gcno\)\)" -exec rm {} \;
 tags:
 	ctags * -R
 	cscope -b `find . -name '*.cc'` `find . -name '*.h'`
 
+format:
+	build_tools/format-diff.sh
+
 # ---------------------------------------------------------------------------
 # 	Unit tests and tools
 # ---------------------------------------------------------------------------
@@ -174,17 +249,20 @@ $(LIBRARY): $(LIBOBJECTS)
 db_bench: db/db_bench.o $(LIBOBJECTS) $(TESTUTIL)
 	$(CXX) db/db_bench.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
 
+block_hash_index_test: table/block_hash_index_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	 $(CXX) table/block_hash_index_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
 db_stress: tools/db_stress.o $(LIBOBJECTS) $(TESTUTIL)
 	$(CXX) tools/db_stress.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
 
+db_sanity_test: tools/db_sanity_test.o $(LIBOBJECTS) $(TESTUTIL)
+	$(CXX) tools/db_sanity_test.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
+
 db_repl_stress: tools/db_repl_stress.o $(LIBOBJECTS) $(TESTUTIL)
 	$(CXX) tools/db_repl_stress.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
 
-db_bench_sqlite3: doc/bench/db_bench_sqlite3.o $(LIBOBJECTS) $(TESTUTIL)
-	$(CXX) doc/bench/db_bench_sqlite3.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) -lsqlite3 $(COVERAGEFLAGS)
-
-db_bench_tree_db: doc/bench/db_bench_tree_db.o $(LIBOBJECTS) $(TESTUTIL)
-	$(CXX) doc/bench/db_bench_tree_db.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) -lkyotocabinet $(COVERAGEFLAGS)
+blob_store_bench: tools/blob_store_bench.o $(LIBOBJECTS) $(TESTUTIL)
+	$(CXX) tools/blob_store_bench.o $(LIBOBJECTS) $(TESTUTIL) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
 
 signal_test: util/signal_test.o $(LIBOBJECTS)
 	$(CXX) util/signal_test.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
@@ -192,9 +270,21 @@ signal_test: util/signal_test.o $(LIBOBJECTS)
 arena_test: util/arena_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) util/arena_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
+autovector_test: util/autovector_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) util/autovector_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
+column_family_test: db/column_family_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) db/column_family_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
+table_properties_collector_test: db/table_properties_collector_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) db/table_properties_collector_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
 bloom_test: util/bloom_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) util/bloom_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
+dynamic_bloom_test: util/dynamic_bloom_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) util/dynamic_bloom_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
 c_test: db/c_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) db/c_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
@@ -204,15 +294,24 @@ cache_test: util/cache_test.o $(LIBOBJECTS) $(TESTHARNESS)
 coding_test: util/coding_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) util/coding_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
+blob_store_test: util/blob_store_test.o $(LIBOBJECTS) $(TESTHARNESS) $(TESTUTIL)
+	$(CXX) util/blob_store_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o$@ $(LDFLAGS) $(COVERAGEFLAGS)
+
 stringappend_test: utilities/merge_operators/string_append/stringappend_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) utilities/merge_operators/string_append/stringappend_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
 redis_test: utilities/redis/redis_lists_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) utilities/redis/redis_lists_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
+benchharness_test: util/benchharness_test.o $(LIBOBJECTS) $(TESTHARNESS) $(BENCHHARNESS)
+	$(CXX) util/benchharness_test.o $(LIBOBJECTS) $(TESTHARNESS) $(BENCHHARNESS) $(EXEC_LDFLAGS) -o$@ $(LDFLAGS) $(COVERAGEFLAGS)
+
 histogram_test: util/histogram_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) util/histogram_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o$@ $(LDFLAGS) $(COVERAGEFLAGS)
 
+thread_local_test: util/thread_local_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) util/thread_local_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
 corruption_test: db/corruption_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) db/corruption_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
@@ -222,9 +321,36 @@ crc32c_test: util/crc32c_test.o $(LIBOBJECTS) $(TESTHARNESS)
 db_test: db/db_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) db/db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
+log_write_bench: util/log_write_bench.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) util/log_write_bench.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS) -pg
+
+plain_table_db_test: db/plain_table_db_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) db/plain_table_db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
+simple_table_db_test: db/simple_table_db_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) db/simple_table_db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
+table_reader_bench: table/table_reader_bench.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) table/table_reader_bench.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS) -pg
+
+log_and_apply_bench: db/log_and_apply_bench.o $(LIBOBJECTS) $(TESTHARNESS) $(BENCHHARNESS)
+	$(CXX) db/log_and_apply_bench.o $(LIBOBJECTS) $(TESTHARNESS) $(BENCHHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS) -pg
+
 perf_context_test: db/perf_context_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) db/perf_context_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
 
+prefix_test: db/prefix_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) db/prefix_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
+
+backupable_db_test: utilities/backupable/backupable_db_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) utilities/backupable/backupable_db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
+
+document_db_test: utilities/document/document_db_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) utilities/document/document_db_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
+
+json_document_test: utilities/document/json_document_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) utilities/document/json_document_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
+
 ttl_test: utilities/ttl/ttl_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) utilities/ttl/ttl_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@  $(LDFLAGS) $(COVERAGEFLAGS)
 
@@ -234,6 +360,9 @@ dbformat_test: db/dbformat_test.o $(LIBOBJECTS) $(TESTHARNESS)
 env_test: util/env_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) util/env_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
+rate_limiter_test: util/rate_limiter_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) util/rate_limiter_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
 filename_test: db/filename_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) db/filename_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
@@ -258,6 +387,9 @@ version_edit_test: db/version_edit_test.o $(LIBOBJECTS) $(TESTHARNESS)
 version_set_test: db/version_set_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) db/version_set_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
+file_indexer_test : db/file_indexer_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) db/file_indexer_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
 reduce_levels_test: tools/reduce_levels_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) tools/reduce_levels_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
@@ -270,12 +402,15 @@ merge_test: db/merge_test.o $(LIBOBJECTS) $(TESTHARNESS)
 deletefile_test: db/deletefile_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) db/deletefile_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS)
 
+geodb_test: utilities/geodb/geodb_test.o $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) utilities/geodb/geodb_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+
 $(MEMENVLIBRARY) : $(MEMENVOBJECTS)
 	rm -f $@
 	$(AR) -rs $@ $(MEMENVOBJECTS)
 
-memenv_test : helpers/memenv/memenv_test.o $(MEMENVLIBRARY) $(LIBRARY) $(TESTHARNESS)
-	$(CXX) helpers/memenv/memenv_test.o $(MEMENVLIBRARY) $(LIBRARY) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
+memenv_test : helpers/memenv/memenv_test.o $(MEMENVOBJECTS) $(LIBOBJECTS) $(TESTHARNESS)
+	$(CXX) helpers/memenv/memenv_test.o $(MEMENVOBJECTS) $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
 manual_compaction_test: util/manual_compaction_test.o $(LIBOBJECTS) $(TESTHARNESS)
 	$(CXX) util/manual_compaction_test.o $(LIBOBJECTS) $(TESTHARNESS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
@@ -298,6 +433,35 @@ sst_dump: tools/sst_dump.o $(LIBOBJECTS)
 ldb: tools/ldb.o $(LIBOBJECTS)
 	$(CXX) tools/ldb.o $(LIBOBJECTS) $(EXEC_LDFLAGS) -o $@ $(LDFLAGS) $(COVERAGEFLAGS)
 
+# ---------------------------------------------------------------------------
+# Jni stuff
+# ---------------------------------------------------------------------------
+
+JNI_NATIVE_SOURCES = ./java/rocksjni/*.cc
+JAVA_INCLUDE = -I$(JAVA_HOME)/include/ -I$(JAVA_HOME)/include/linux
+ROCKSDBJNILIB = ./java/librocksdbjni.so
+
+ifeq ($(PLATFORM), OS_MACOSX)
+ROCKSDBJNILIB = ./java/librocksdbjni.jnilib
+JAVA_INCLUDE = -I/System/Library/Frameworks/JavaVM.framework/Headers/
+endif
+
+rocksdbjava:
+	OPT="-fPIC -DNDEBUG -O2" $(MAKE) $(LIBRARY) -j32
+	cd java;$(MAKE) java;
+	rm -f $(ROCKSDBJNILIB)
+	$(CXX) $(CXXFLAGS) -I./java/. $(JAVA_INCLUDE) -shared -fPIC -o $(ROCKSDBJNILIB) $(JNI_NATIVE_SOURCES) $(LIBOBJECTS) $(LDFLAGS) $(COVERAGEFLAGS)
+
+jclean:
+	cd java;$(MAKE) clean;
+	rm -f $(ROCKSDBJNILIB)
+
+jtest:
+	cd java;$(MAKE) sample;$(MAKE) test;
+
+jdb_bench:
+	cd java;$(MAKE) db_bench;
+
 # ---------------------------------------------------------------------------
 #  	Platform-specific compilation
 # ---------------------------------------------------------------------------
@@ -308,20 +472,20 @@ ifeq ($(PLATFORM), IOS)
 PLATFORMSROOT=/Applications/Xcode.app/Contents/Developer/Platforms
 SIMULATORROOT=$(PLATFORMSROOT)/iPhoneSimulator.platform/Developer
 DEVICEROOT=$(PLATFORMSROOT)/iPhoneOS.platform/Developer
-IOSVERSION=$(shell defaults read $(PLATFORMSROOT)/iPhoneOS.platform/versionCFBundleShortVersionString)
+IOSVERSION=$(shell defaults read $(PLATFORMSROOT)/iPhoneOS.platform/version CFBundleShortVersionString)
 
 .cc.o:
 	mkdir -p ios-x86/$(dir $@)
-	$(SIMULATORROOT)/usr/bin/$(CXX) $(CXXFLAGS) -isysroot $(SIMULATORROOT)/SDKs/iPhoneSimulator$(IOSVERSION).sdk -arch i686 -c $< -o ios-x86/$@ $(COVERAGEFLAGS)
+	$(CXX) $(CXXFLAGS) -isysroot $(SIMULATORROOT)/SDKs/iPhoneSimulator$(IOSVERSION).sdk -arch i686 -arch x86_64 -c $< -o ios-x86/$@
 	mkdir -p ios-arm/$(dir $@)
-	$(DEVICEROOT)/usr/bin/$(CXX) $(CXXFLAGS) -isysroot $(DEVICEROOT)/SDKs/iPhoneOS$(IOSVERSION).sdk -arch armv6 -arch armv7 -c $< -o ios-arm/$@ $(COVERAGEFLAGS)
+	xcrun -sdk iphoneos $(CXX) $(CXXFLAGS) -isysroot $(DEVICEROOT)/SDKs/iPhoneOS$(IOSVERSION).sdk -arch armv6 -arch armv7 -arch armv7s -arch arm64 -c $< -o ios-arm/$@
 	lipo ios-x86/$@ ios-arm/$@ -create -output $@
 
 .c.o:
 	mkdir -p ios-x86/$(dir $@)
-	$(SIMULATORROOT)/usr/bin/$(CC) $(CFLAGS) -isysroot $(SIMULATORROOT)/SDKs/iPhoneSimulator$(IOSVERSION).sdk -arch i686 -c $< -o ios-x86/$@
+	$(CC) $(CFLAGS) -isysroot $(SIMULATORROOT)/SDKs/iPhoneSimulator$(IOSVERSION).sdk -arch i686 -arch x86_64 -c $< -o ios-x86/$@
 	mkdir -p ios-arm/$(dir $@)
-	$(DEVICEROOT)/usr/bin/$(CC) $(CFLAGS) -isysroot $(DEVICEROOT)/SDKs/iPhoneOS$(IOSVERSION).sdk -arch armv6 -arch armv7 -c $< -o ios-arm/$@
+	xcrun -sdk iphoneos $(CC) $(CFLAGS) -isysroot $(DEVICEROOT)/SDKs/iPhoneOS$(IOSVERSION).sdk -arch armv6 -arch armv7 -arch armv7s -arch arm64 -c $< -o ios-arm/$@
 	lipo ios-x86/$@ ios-arm/$@ -create -output $@
 
 else
@@ -345,12 +509,26 @@ endif
 # the correct path prefix.
 %.d: %.cc
 	$(CXX) $(CXXFLAGS) $(PLATFORM_SHARED_CFLAGS) -MM $< -o $@
-	@sed -i -e 's|.*:|$*.o:|' $@
+ifeq ($(PLATFORM), OS_MACOSX)
+	@sed -i '' -e 's,.*:,$*.o:,' $@
+else
+	@sed -i -e 's,.*:,$*.o:,' $@
+endif
 
 DEPFILES = $(filter-out util/build_version.d,$(SOURCES:.cc=.d))
 
 depend: $(DEPFILES)
 
+# if the make goal is either "clean" or "format", we shouldn't
+# try to import the *.d files.
+# TODO(kailiu) The unfamiliarity of Make's conditions leads to the ugly
+# working solution.
 ifneq ($(MAKECMDGOALS),clean)
+ifneq ($(MAKECMDGOALS),format)
+ifneq ($(MAKECMDGOALS),jclean)
+ifneq ($(MAKECMDGOALS),jtest)
 -include $(DEPFILES)
 endif
+endif
+endif
+endif

PATENTS

@@ -0,0 +1,23 @@
+Additional Grant of Patent Rights
+
+“Software” means the rocksdb software distributed by Facebook, Inc.
+
+Facebook hereby grants you a perpetual, worldwide, royalty-free,
+non-exclusive, irrevocable (subject to the termination provision below)
+license under any rights in any patent claims owned by Facebook, to make,
+have made, use, sell, offer to sell, import, and otherwise transfer the
+Software. For avoidance of doubt, no license is granted under Facebook’s
+rights in any patent claims that are infringed by (i) modifications to the
+Software made by you or a third party, or (ii) the Software in combination
+with any software or other technology provided by you or a third party.
+
+The license granted hereunder will terminate, automatically and without
+notice, for anyone that makes any claim (including by filing any lawsuit,
+assertion or other action) alleging (a) direct, indirect, or contributory
+infringement or inducement to infringe any patent: (i) by Facebook or any
+of its subsidiaries or affiliates, whether or not such claim is related
+to the Software, (ii) by any party if such claim arises in whole or in
+part from any software, product or service of Facebook or any of its
+subsidiaries or affiliates, whether or not such claim is related to the
+Software, or (iii) by any party relating to the Software; or (b) that
+any right in any patent claim of Facebook is invalid or unenforceable.

README

@@ -1,82 +0,0 @@
-rocksdb: A persistent key-value store for flash storage
-Authors: * The Facebook Database Engineering Team
-         * Build on earlier work on leveldb by Sanjay Ghemawat
-           (sanjay@google.com) and Jeff Dean (jeff@google.com)
-
-This code is a library that forms the core building block for a fast
-key value server, especially suited for storing data on flash drives.
-It has an Log-Stuctured-Merge-Database (LSM) design with flexible tradeoffs
-between Write-Amplification-Factor(WAF), Read-Amplification-Factor (RAF)
-and Space-Amplification-Factor(SAF). It has multi-threaded compactions,
-making it specially suitable for storing multiple terabytes of data in a
-single database.
-
-The core of this code has been derived from open-source leveldb.
-
-The code under this directory implements a system for maintaining a
-persistent key/value store.
-
-See doc/index.html for more explanation.
-See doc/impl.html for a brief overview of the implementation.
-
-The public interface is in include/*.  Callers should not include or
-rely on the details of any other header files in this package.  Those
-internal APIs may be changed without warning.
-
-Guide to header files:
-
-include/rocksdb/db.h
-    Main interface to the DB: Start here
-
-include/rocksdb/options.h
-    Control over the behavior of an entire database, and also
-    control over the behavior of individual reads and writes.
-
-include/rocksdb/comparator.h
-    Abstraction for user-specified comparison function.  If you want
-    just bytewise comparison of keys, you can use the default comparator,
-    but clients can write their own comparator implementations if they
-    want custom ordering (e.g. to handle different character
-    encodings, etc.)
-
-include/rocksdb/iterator.h
-    Interface for iterating over data. You can get an iterator
-    from a DB object.
-
-include/rocksdb/write_batch.h
-    Interface for atomically applying multiple updates to a database.
-
-include/rocksdb/slice.h
-    A simple module for maintaining a pointer and a length into some
-    other byte array.
-
-include/rocksdb/status.h
-    Status is returned from many of the public interfaces and is used
-    to report success and various kinds of errors.
-
-include/rocksdb/env.h
-    Abstraction of the OS environment.  A posix implementation of
-    this interface is in util/env_posix.cc
-
-include/rocksdb/table_builder.h
-    Lower-level modules that most clients probably won't use directly
-
-include/rocksdb/cache.h
-    An API for the block cache.
-
-include/rocksdb/compaction_filter.h
-    An API for a application filter invoked on every compaction.
-
-include/rocksdb/filter_policy.h
-    An API for configuring a bloom filter.
-
-include/rocksdb/memtablerep.h
-    An API for implementing a memtable.
-
-include/rocksdb/statistics.h
-    An API to retrieve various database statistics.
-
-include/rocksdb/transaction_log.h
-    An API to retrieve transaction logs from a database.
-
-

README.fb

@@ -1,3 +0,0 @@
-* Detailed instructions on how to compile using fbcode and jemalloc
-
-* Latest release is 2.4.fb

README.md

@@ -0,0 +1,25 @@
+## RocksDB: A Persistent Key-Value Store for Flash and RAM Storage
+
+[![Build Status](https://travis-ci.org/facebook/rocksdb.svg?branch=master)](https://travis-ci.org/facebook/rocksdb)
+
+RocksDB is developed and maintained by Facebook Database Engineering Team.
+It is built on on earlier work on LevelDB by Sanjay Ghemawat (sanjay@google.com)
+and Jeff Dean (jeff@google.com)
+
+This code is a library that forms the core building block for a fast
+key value server, especially suited for storing data on flash drives.
+It has a Log-Structured-Merge-Database (LSM) design with flexible tradeoffs
+between Write-Amplification-Factor (WAF), Read-Amplification-Factor (RAF)
+and Space-Amplification-Factor (SAF). It has multi-threaded compactions,
+making it specially suitable for storing multiple terabytes of data in a
+single database.
+
+Start with example usage here: https://github.com/facebook/rocksdb/tree/master/examples
+
+See the [github wiki](https://github.com/facebook/rocksdb/wiki) for more explanation.
+
+The public interface is in `include/`.  Callers should not include or
+rely on the details of any other header files in this package.  Those
+internal APIs may be changed without warning.
+
+Design discussions are conducted in https://www.facebook.com/groups/rocksdb.dev/

ROCKSDB_LITE.md

@@ -0,0 +1,20 @@
+# RocksDBLite
+
+RocksDBLite is a project focused on mobile use cases, which don't need a lot of fancy things we've built for server workloads and they are very sensitive to binary size. For that reason, we added a compile flag ROCKSDB_LITE that comments out a lot of the nonessential code and keeps the binary lean.
+
+Some examples of the features disabled by ROCKSDB_LITE:
+* compiled-in support for LDB tool
+* No backupable DB
+* No support for replication (which we provide in form of TrasactionalIterator)
+* No advanced monitoring tools
+* No special-purpose memtables that are highly optimized for specific use cases
+
+When adding a new big feature to RocksDB, please add ROCKSDB_LITE compile guard if:
+* Nobody from mobile really needs your feature,
+* Your feature is adding a lot of weight to the binary.
+
+Don't add ROCKSDB_LITE compile guard if:
+* It would introduce a lot of code complexity. Compile guards make code harder to read. It's a trade-off.
+* Your feature is not adding a lot of weight.
+
+If unsure, ask. :)

build_tools/build_detect_platform

@@ -19,8 +19,19 @@
 #
 #       -DLEVELDB_PLATFORM_POSIX if cstdatomic is present
 #       -DLEVELDB_PLATFORM_NOATOMIC if it is not
-#       -DSNAPPY                     if the Snappy library is present
+#       -DSNAPPY                    if the Snappy library is present
+#       -DLZ4                       if the LZ4 library is present
+#       -DNUMA                      if the NUMA library is present
 #
+# Using gflags in rocksdb:
+# Our project depends on gflags, which requires users to take some extra steps
+# before they can compile the whole repository:
+#   1. Install gflags. You may download it from here:
+#      https://code.google.com/p/gflags/
+#   2. Once install, add the include path/lib path for gflags to CPATH and
+#      LIBRARY_PATH respectively. If installed with default mode, the
+#      lib and include path will be /usr/local/lib and /usr/local/include
+# Mac user can do this by running build_tools/mac-install-gflags.sh
 
 OUTPUT=$1
 if test -z "$OUTPUT"; then
@@ -28,18 +39,24 @@ if test -z "$OUTPUT"; then
   exit 1
 fi
 
+# we depend on C++11
+PLATFORM_CXXFLAGS="-std=c++11"
+# we currently depend on POSIX platform
+COMMON_FLAGS="-DROCKSDB_PLATFORM_POSIX"
+
 # Default to fbcode gcc on internal fb machines
 if [ -d /mnt/gvfs/third-party -a -z "$CXX" ]; then
+    FBCODE_BUILD="true"
     if [ -z "$USE_CLANG" ]; then
-        source $PWD/build_tools/fbcode.gcc471.sh
+        source $PWD/build_tools/fbcode_config.sh
     else
-        source $PWD/build_tools/fbcode.clang31.sh
+        source "$PWD/build_tools/fbcode.clang31.sh"
     fi
 fi
 
 # Delete existing output, if it exists
-rm -f $OUTPUT
-touch $OUTPUT
+rm -f "$OUTPUT"
+touch "$OUTPUT"
 
 if test -z "$CC"; then
    CC=cc
@@ -54,28 +71,35 @@ if test -z "$TARGET_OS"; then
     TARGET_OS=`uname -s`
 fi
 
-COMMON_FLAGS="${CFLAGS}"
+COMMON_FLAGS="$COMMON_FLAGS ${CFLAGS}"
 CROSS_COMPILE=
 PLATFORM_CCFLAGS=
-PLATFORM_CXXFLAGS="${CXXFLAGS}"
+PLATFORM_CXXFLAGS="$PLATFORM_CXXFLAGS ${CXXFLAGS}"
 PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS"
 PLATFORM_SHARED_EXT="so"
-PLATFORM_SHARED_LDFLAGS="${EXEC_LDFLAGS_SHARED} -shared -Wl,-soname -Wl,"
+PLATFORM_SHARED_LDFLAGS="-shared -Wl,-soname -Wl,"
 PLATFORM_SHARED_CFLAGS="-fPIC"
-PLATFORM_SHARED_VERSIONED=true
+PLATFORM_SHARED_VERSIONED=false
 
 # generic port files (working on all platform by #ifdef) go directly in /port
-GENERIC_PORT_FILES=`find $ROCKSDB_ROOT/port -name '*.cc' | tr "\n" " "`
+GENERIC_PORT_FILES=`cd "$ROCKSDB_ROOT"; find port -name '*.cc' | tr "\n" " "`
 
 # On GCC, we pick libc's memcmp over GCC's memcmp via -fno-builtin-memcmp
 case "$TARGET_OS" in
     Darwin)
         PLATFORM=OS_MACOSX
-        COMMON_FLAGS="$COMMON_FLAGS -fno-builtin-memcmp -DOS_MACOSX"
+        COMMON_FLAGS="$COMMON_FLAGS -DOS_MACOSX"
         PLATFORM_SHARED_EXT=dylib
         PLATFORM_SHARED_LDFLAGS="-dynamiclib -install_name "
         # PORT_FILES=port/darwin/darwin_specific.cc
         ;;
+    IOS)
+        PLATFORM=IOS
+        COMMON_FLAGS="$COMMON_FLAGS -DOS_MACOSX -DIOS_CROSS_COMPILE -DROCKSDB_LITE"
+        PLATFORM_SHARED_EXT=dylib
+        PLATFORM_SHARED_LDFLAGS="-dynamiclib -install_name "
+        CROSS_COMPILE=true
+        ;;
     Linux)
         PLATFORM=OS_LINUX
         COMMON_FLAGS="$COMMON_FLAGS -DOS_LINUX"
@@ -127,49 +151,53 @@ case "$TARGET_OS" in
         exit 1
 esac
 
-$PWD/build_tools/build_detect_version
+if test -z "$DO_NOT_RUN_BUILD_DETECT_VERSION"; then
+  "$PWD/build_tools/build_detect_version"
+fi
 
 # We want to make a list of all cc files within util, db, table, and helpers
 # except for the test and benchmark files. By default, find will output a list
 # of all files matching either rule, so we need to append -print to make the
 # prune take effect.
 DIRS="util db table utilities"
-if test "$USE_THRIFT"; then
-  DIRS="$DIRS thrift/server_utils.cpp thrift/gen-cpp "
-  THRIFTSERVER=leveldb_server
-fi
-
-if test "$USE_SCRIBE"; then
-  DIRS="$DIRS scribe "
-fi
 
 set -f # temporarily disable globbing so that our patterns arent expanded
 PRUNE_TEST="-name *test*.cc -prune"
-PRUNE_BENCH="-name *_bench.cc -prune"
-PORTABLE_FILES=`cd $ROCKSDB_ROOT; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cc' -print | sort | tr "\n" " "`
-PORTABLE_CPP=`cd $ROCKSDB_ROOT; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cpp' -print | sort | tr "\n" " "`
+PRUNE_BENCH="-name *bench*.cc -prune"
+PORTABLE_FILES=`cd "$ROCKSDB_ROOT"; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cc' -print | sort | tr "\n" " "`
+PORTABLE_CPP=`cd "$ROCKSDB_ROOT"; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cpp' -print | sort | tr "\n" " "`
 set +f # re-enable globbing
 
 # The sources consist of the portable files, plus the platform-specific port
 # file.
-echo "SOURCES=$PORTABLE_FILES $GENERIC_PORT_FILES $PORT_FILES" >> $OUTPUT
-echo "SOURCESCPP=$PORTABLE_CPP" >> $OUTPUT
-echo "MEMENV_SOURCES=helpers/memenv/memenv.cc" >> $OUTPUT
+echo "SOURCES=$PORTABLE_FILES $GENERIC_PORT_FILES $PORT_FILES" >> "$OUTPUT"
+echo "SOURCESCPP=$PORTABLE_CPP" >> "$OUTPUT"
+echo "MEMENV_SOURCES=helpers/memenv/memenv.cc" >> "$OUTPUT"
 
-if [ "$CROSS_COMPILE" = "true" ]; then
+if [ "$CROSS_COMPILE" = "true" -o "$FBCODE_BUILD" = "true" ]; then
     # Cross-compiling; do not try any compilation tests.
+    # Also don't need any compilation tests if compiling on fbcode
     true
 else
-    # If -std=c++0x works, use <cstdatomic>.  Otherwise use port_posix.h.
+    # If -std=c++0x works, use <atomic>.  Otherwise use port_posix.h.
     $CXX $CFLAGS -std=c++0x -x c++ - -o /dev/null 2>/dev/null  <<EOF
-      #include <cstdatomic>
+      #include <atomic>
       int main() {}
 EOF
     if [ "$?" = 0 ]; then
-        COMMON_FLAGS="$COMMON_FLAGS -DLEVELDB_PLATFORM_POSIX -DLEVELDB_CSTDATOMIC_PRESENT"
-        PLATFORM_CXXFLAGS="-std=c++0x"
-    else
-        COMMON_FLAGS="$COMMON_FLAGS -DLEVELDB_PLATFORM_POSIX"
+        COMMON_FLAGS="$COMMON_FLAGS -DROCKSDB_ATOMIC_PRESENT"
+    fi
+
+    # Test whether fallocate is available
+    $CXX $CFLAGS -x c++ - -o /dev/null 2>/dev/null  <<EOF
+      #include <fcntl.h>
+      int main() {
+	int fd = open("/dev/null", 0);
+	fallocate(fd, 0, 0, 1024);
+      }
+EOF
+    if [ "$?" = 0 ]; then
+        COMMON_FLAGS="$COMMON_FLAGS -DROCKSDB_FALLOCATE_PRESENT"
     fi
 
     # Test whether Snappy library is installed
@@ -180,7 +208,32 @@ EOF
 EOF
     if [ "$?" = 0 ]; then
         COMMON_FLAGS="$COMMON_FLAGS -DSNAPPY"
-        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS ${SNAPPY_LDFLAGS:-./snappy/libs/libsnappy.a}"
+        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lsnappy"
+    fi
+
+
+    # Test whether gflags library is installed
+    # http://code.google.com/p/gflags/
+    # check if the namespace is gflags
+    $CXX $CFLAGS -x c++ - -o /dev/null 2>/dev/null  <<EOF
+      #include <gflags/gflags.h>
+      using namespace gflags;
+      int main() {}
+EOF
+    if [ "$?" = 0 ]; then
+        COMMON_FLAGS="$COMMON_FLAGS -DGFLAGS=gflags"
+        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lgflags"
+    fi
+
+    # check if namespace is google
+    $CXX $CFLAGS -x c++ - -o /dev/null 2>/dev/null  <<EOF
+      #include <gflags/gflags.h>
+      using namespace google;
+      int main() {}
+EOF
+    if [ "$?" = 0 ]; then
+        COMMON_FLAGS="$COMMON_FLAGS -DGFLAGS=gflags"
+        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lgflags"
     fi
 
     # Test whether zlib library is installed
@@ -203,6 +256,28 @@ EOF
         PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lbz2"
     fi
 
+    # Test whether lz4 library is installed
+    $CXX $CFLAGS $COMMON_FLAGS -x c++ - -o /dev/null 2>/dev/null  <<EOF
+      #include <lz4.h>
+      #include <lz4hc.h>
+      int main() {}
+EOF
+    if [ "$?" = 0 ]; then
+        COMMON_FLAGS="$COMMON_FLAGS -DLZ4"
+        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -llz4"
+    fi
+
+    # Test whether numa is available
+    $CXX $CFLAGS -x c++ - -o /dev/null -lnuma 2>/dev/null  <<EOF
+      #include <numa.h>
+      #inlcude <numaif.h>
+      int main() {}
+EOF
+    if [ "$?" = 0 ]; then
+        COMMON_FLAGS="$COMMON_FLAGS -DNUMA"
+        PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS -lnuma"
+    fi
+
     # Test whether tcmalloc is available
     $CXX $CFLAGS -x c++ - -o /dev/null -ltcmalloc 2>/dev/null  <<EOF
       int main() {}
@@ -220,21 +295,13 @@ if test "$USE_HDFS"; then
     exit 1
   fi
   HDFS_CCFLAGS="$HDFS_CCFLAGS -I$JAVA_HOME/include -I$JAVA_HOME/include/linux -DUSE_HDFS"
-  HDFS_LDFLAGS="$HDFS_LDFLAGS -Wl,--no-whole-archive hdfs/libhdfs.a -L$JAVA_HOME/jre/lib/amd64"
+  HDFS_LDFLAGS="$HDFS_LDFLAGS -Wl,--no-whole-archive -lhdfs -L$JAVA_HOME/jre/lib/amd64"
   HDFS_LDFLAGS="$HDFS_LDFLAGS -L$JAVA_HOME/jre/lib/amd64/server -L$GLIBC_RUNTIME_PATH/lib"
   HDFS_LDFLAGS="$HDFS_LDFLAGS -ldl -lverify -ljava -ljvm"
   COMMON_FLAGS="$COMMON_FLAGS $HDFS_CCFLAGS"
   PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS $HDFS_LDFLAGS"
 fi
 
-# shall we build thrift server or scribe logger
-if test "$USE_THRIFT" ||  test "$USE_SCRIBE" ; then
-    THRIFT_CCFLAGS=" -I./thrift -I./thrift/gen-cpp -I./thrift/lib/cpp -I/usr/include -std=gnu++0x"
-    THRIFT_LDFLAGS=" -lexample -lserver -lthrift_base -ltransport -lthrift_exception -lutil -L./thrift/libs "
-    COMMON_FLAGS="$COMMON_FLAGS $THRIFT_CCFLAGS"
-    PLATFORM_LDFLAGS="$PLATFORM_LDFLAGS $THRIFT_LDFLAGS"
-fi
-
 # if Intel SSE instruction set is supported, set USE_SSE=" -msse -msse4.2 "
 COMMON_FLAGS="$COMMON_FLAGS $USE_SSE"
 
@@ -243,16 +310,17 @@ PLATFORM_CXXFLAGS="$PLATFORM_CXXFLAGS $COMMON_FLAGS"
 
 VALGRIND_VER="$VALGRIND_VER"
 
-echo "CC=$CC" >> $OUTPUT
-echo "CXX=$CXX" >> $OUTPUT
-echo "PLATFORM=$PLATFORM" >> $OUTPUT
-echo "PLATFORM_LDFLAGS=$PLATFORM_LDFLAGS" >> $OUTPUT
-echo "VALGRIND_VER=$VALGRIND_VER" >> $OUTPUT
-echo "PLATFORM_CCFLAGS=$PLATFORM_CCFLAGS" >> $OUTPUT
-echo "PLATFORM_CXXFLAGS=$PLATFORM_CXXFLAGS" >> $OUTPUT
-echo "PLATFORM_SHARED_CFLAGS=$PLATFORM_SHARED_CFLAGS" >> $OUTPUT
-echo "PLATFORM_SHARED_EXT=$PLATFORM_SHARED_EXT" >> $OUTPUT
-echo "PLATFORM_SHARED_LDFLAGS=$PLATFORM_SHARED_LDFLAGS" >> $OUTPUT
-echo "PLATFORM_SHARED_VERSIONED=$PLATFORM_SHARED_VERSIONED" >> $OUTPUT
-echo "THRIFTSERVER=$THRIFTSERVER" >> $OUTPUT
-echo "EXEC_LDFLAGS=$EXEC_LDFLAGS" >> $OUTPUT
+echo "CC=$CC" >> "$OUTPUT"
+echo "CXX=$CXX" >> "$OUTPUT"
+echo "PLATFORM=$PLATFORM" >> "$OUTPUT"
+echo "PLATFORM_LDFLAGS=$PLATFORM_LDFLAGS" >> "$OUTPUT"
+echo "VALGRIND_VER=$VALGRIND_VER" >> "$OUTPUT"
+echo "PLATFORM_CCFLAGS=$PLATFORM_CCFLAGS" >> "$OUTPUT"
+echo "PLATFORM_CXXFLAGS=$PLATFORM_CXXFLAGS" >> "$OUTPUT"
+echo "PLATFORM_SHARED_CFLAGS=$PLATFORM_SHARED_CFLAGS" >> "$OUTPUT"
+echo "PLATFORM_SHARED_EXT=$PLATFORM_SHARED_EXT" >> "$OUTPUT"
+echo "PLATFORM_SHARED_LDFLAGS=$PLATFORM_SHARED_LDFLAGS" >> "$OUTPUT"
+echo "PLATFORM_SHARED_VERSIONED=$PLATFORM_SHARED_VERSIONED" >> "$OUTPUT"
+echo "EXEC_LDFLAGS=$EXEC_LDFLAGS" >> "$OUTPUT"
+echo "JEMALLOC_INCLUDE=$JEMALLOC_INCLUDE" >> "$OUTPUT"
+echo "JEMALLOC_LIB=$JEMALLOC_LIB" >> "$OUTPUT"

build_tools/build_detect_version

@@ -5,38 +5,18 @@
 # is then built as a regular source file as part of the compilation process.
 # One can run "strings executable_filename | grep _build_" to find the version of
 # the source that we used to build the executable file.
-#
 
-# create git version file
-VFILE=$ROCKSDB_ROOT/util/build_version.cc.tmp
-trap "rm $VFILE" EXIT
+OUTFILE="$PWD/util/build_version.cc"
 
-# check to see if git is in the path
-which git > /dev/null
-
-if [ "$?" = 0 ]; then
-  env -i git rev-parse HEAD |
-  awk '
-  BEGIN {
-    print "#include \"build_version.h\"\n"
-  }
-  { print "const char* leveldb_build_git_sha = \"leveldb_build_git_sha:" $0"\";" }
-  ' >  ${VFILE}
-else
-  echo "git not found" |
-  awk '
-    BEGIN {
-      print "#include \"build_version.h\""
-    }
-    { print "const char* leveldb_build_git_sha = \"leveldb_build_git_sha:git not found\";" }
-    ' > ${VFILE}
+GIT_SHA=""
+if command -v git >/dev/null 2>&1; then
+    GIT_SHA=$(git rev-parse HEAD 2>/dev/null)
 fi
 
-echo "const char* leveldb_build_git_datetime = \"leveldb_build_git_datetime:$(date)\";" >> ${VFILE}
-echo "const char* leveldb_build_compile_date = __DATE__;" >> ${VFILE}
-echo "const char* leveldb_build_compile_time = __TIME__;" >> ${VFILE}
-
-OUTFILE=$ROCKSDB_ROOT/util/build_version.cc
-if [ ! -e $OUTFILE ] || ! cmp -s $VFILE $OUTFILE; then
-    cp $VFILE $OUTFILE
-fi
+cat > "${OUTFILE}" <<EOF
+#include "build_version.h"
+const char* rocksdb_build_git_sha = "rocksdb_build_git_sha:${GIT_SHA}";
+const char* rocksdb_build_git_datetime = "rocksdb_build_git_datetime:$(date)";
+const char* rocksdb_build_compile_date = __DATE__;
+const char* rocksdb_build_compile_time = __TIME__;
+EOF

build_tools/build_java.sh

@@ -1,86 +0,0 @@
-#!/bin/bash -e
-function print_usage {
-  echo "Usage: $0 [build | release | bump_version version ]"
-}
-
-function check_env {
-  if [ -z $LEVELDB_HOME ] ; then
-    echo "Expect LEVELDB_HOME to be SET"
-    exit 1
-  fi
-  if [ -z $JAVA_HOME ] ; then
-    export JAVA_HOME=/usr/local/jdk-6u14-64/
-    echo "JAVA_HOME not set. Assuming JAVA_HOME=$JAVA_HOME"
-  fi
-  if [ -z $LEVELDBJNI_HOME ] ; then
-    export LEVELDBJNI_HOME=$LEVELDB_HOME/java/leveldbjni/
-    echo "LEVELDBJNI_HOME not set. Assuming LEVELDBJNI_HOME=$LEVELDBJNI_HOME"
-  fi
-  if [ -z $SNAPPY_HOME ] ; then
-    export SNAPPY_HOME="/home/dhruba/snappy-1.0.5"
-    echo "SNAPPY_HOME not set. Assuming SNAPPY_HOME=$SNAPPY_HOME"
-  fi
-  if [ -z $LEVELDB_PATCH ] ; then 
-    LEVELDB_PATCH=$LEVELDB_HOME/java/leveldbjni/db.h.patch
-    echo "LEVELDB_PATCH not set. Assuming LEVELDB_PATCH=$LEVELDB_PATCH"
-  fi
-}
-
-function build {
-  cd $LEVELDB_HOME
-  git apply $LEVELDB_PATCH
-  make clean libleveldb.a
-  cd $LEVELDB_HOME/java/leveldb/leveldb-api
-  mvn clean package
-  cd $LEVELDBJNI_HOME
-  mvn clean install -P linux64
-  cd $LEVELDB_HOME
-  git checkout $LEVELDB_HOME/include/leveldb/db.h
-}
-
-function release {
-  cd $LEVELDB_HOME
-  git apply $LEVELDB_PATCH
-  make clean libleveldb.a
-  cd $LEVELDB_HOME/java/leveldb/leveldb-api
-  mvn clean package
-  cd $LEVELDBJNI_HOME
-  mvn deploy -P linux64 -DskipTests
-  cd $LEVELDB_HOME
-  git checkout $LEVELDB_HOME/include/leveldb/db.h
-}
-
-CMD=$1
-if [ -z $CMD ]; then
-  print_usage
-  exit 1
-fi
-
-case "$CMD" in 
-  build) 
-    check_env
-    build
-    ;;
-  bump_version)
-    if [ -z $2 ] ; then
-      echo "bump_version requires a version.no parameter at the end"
-      exit 1
-    fi 
-    check_env
-    VERSION=$2
-    pushd $LEVELDBJNI_HOME
-    mvn versions:set -DnewVersion="$VERSION"
-    popd
-    echo "VERSION SET TO $VERSION"
-    ;;
-  release)
-    check_env
-    pushd $LEVELDBJNI_HOME
-    release
-    popd
-    ;;
-  *)
-    print_usage
-    exit 1
-    ;;
-esac

build_tools/dependencies.sh

@@ -0,0 +1,19 @@
+# Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+GCC_BASE=/mnt/gvfs/third-party2/gcc/7331085db891a2ef4a88a48a751d834e8d68f4cb/7.x/centos7-native/b2ef2b6
+CLANG_BASE=/mnt/gvfs/third-party2/llvm-fb/963d9aeda70cc4779885b1277484fe7544a04e3e/9.0.0/platform007/9e92d53/
+LIBGCC_BASE=/mnt/gvfs/third-party2/libgcc/6ace84e956873d53638c738b6f65f3f469cca74c/7.x/platform007/5620abc
+GLIBC_BASE=/mnt/gvfs/third-party2/glibc/192b0f42d63dcf6210d6ceae387b49af049e6e0c/2.26/platform007/f259413
+SNAPPY_BASE=/mnt/gvfs/third-party2/snappy/7f9bdaada18f59bc27ec2b0871eb8a6144343aef/1.1.3/platform007/ca4da3d
+ZLIB_BASE=/mnt/gvfs/third-party2/zlib/2d9f0b9a4274cc21f61272a9e89bdb859bce8f1f/1.2.8/platform007/ca4da3d
+BZIP2_BASE=/mnt/gvfs/third-party2/bzip2/dc49a21c5fceec6456a7a28a94dcd16690af1337/1.0.6/platform007/ca4da3d
+LZ4_BASE=/mnt/gvfs/third-party2/lz4/0f607f8fc442ea7d6b876931b1898bb573d5e5da/1.9.1/platform007/ca4da3d
+ZSTD_BASE=/mnt/gvfs/third-party2/zstd/ca22bc441a4eb709e9e0b1f9fec9750fed7b31c5/1.4.x/platform007/15a3614
+GFLAGS_BASE=/mnt/gvfs/third-party2/gflags/0b9929d2588991c65a57168bf88aff2db87c5d48/2.2.0/platform007/ca4da3d
+JEMALLOC_BASE=/mnt/gvfs/third-party2/jemalloc/c26f08f47ac35fc31da2633b7da92d6b863246eb/master/platform007/c26c002
+NUMA_BASE=/mnt/gvfs/third-party2/numa/3f3fb57a5ccc5fd21c66416c0b83e0aa76a05376/2.0.11/platform007/ca4da3d
+LIBUNWIND_BASE=/mnt/gvfs/third-party2/libunwind/40c73d874898b386a71847f1b99115d93822d11f/1.4/platform007/6f3e0a9
+TBB_BASE=/mnt/gvfs/third-party2/tbb/4ce8e8dba77cdbd81b75d6f0c32fd7a1b76a11ec/2018_U5/platform007/ca4da3d
+KERNEL_HEADERS_BASE=/mnt/gvfs/third-party2/kernel-headers/fb251ecd2f5ae16f8671f7014c246e52a748fe0b/fb/platform007/da39a3e
+BINUTILS_BASE=/mnt/gvfs/third-party2/binutils/ab9f09bba370e7066cafd4eb59752db93f2e8312/2.29.1/platform007/15a3614
+VALGRIND_BASE=/mnt/gvfs/third-party2/valgrind/d42d152a15636529b0861ec493927200ebebca8e/3.15.0/platform007/ca4da3d
+LUA_BASE=/mnt/gvfs/third-party2/lua/f0cd714433206d5139df61659eb7b28b1dea6683/5.3.4/platform007/5007832

build_tools/fbcode.clang31.sh

@@ -4,47 +4,71 @@
 # fbcode settings.  It uses the latest g++ compiler and also
 # uses jemalloc
 
-TOOLCHAIN_REV=f365dbeae46a30414a2874a6f45e73e10f1caf7d
+TOOLCHAIN_REV=fbe3b095a4cc4a3713730050d182b7b4a80c342f
 TOOLCHAIN_EXECUTABLES="/mnt/gvfs/third-party/$TOOLCHAIN_REV/centos5.2-native"
 TOOLCHAIN_LIB_BASE="/mnt/gvfs/third-party/$TOOLCHAIN_REV/gcc-4.7.1-glibc-2.14.1"
-TOOL_JEMALLOC=jemalloc-3.0.0/2f45f3a
+TOOL_JEMALLOC=jemalloc-3.3.1/9202ce3
 GLIBC_RUNTIME_PATH=/usr/local/fbcode/gcc-4.7.1-glibc-2.14.1
 
+# location of libgcc
+LIBGCC_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/include"
+LIBGCC_LIBS=" -L $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/libs"
+
+# location of glibc
+GLIBC_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/glibc/glibc-2.14.1/99df8fc/include"
+GLIBC_LIBS=" -L $TOOLCHAIN_LIB_BASE/glibc/glibc-2.14.1/99df8fc/lib"
+
 # location of snappy headers and libraries
 SNAPPY_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/snappy/snappy-1.0.3/7518bbe/include"
 SNAPPY_LIBS=" $TOOLCHAIN_LIB_BASE/snappy/snappy-1.0.3/7518bbe/lib/libsnappy.a"
 
-# location of boost headers and libraries
-THRIFT_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/boost/boost-1.48.0/bef9365/include -std=gnu++0x"
-THRIFT_INCLUDE+=" -I./thrift -I./thrift/gen-cpp -I./thrift/lib/cpp"
-THRIFT_LIBS=" -L $TOOLCHAIN_LIB_BASE/boost/boost-1.48.0/bef9365/lib"
+# location of zlib headers and libraries
+ZLIB_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/zlib/zlib-1.2.5/91ddd43/include"
+ZLIB_LIBS=" $TOOLCHAIN_LIB_BASE/zlib/zlib-1.2.5/91ddd43/lib/libz.a"
 
-# location of libevent
-LIBEVENT_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/libevent/libevent-1.4.14b/91ddd43/include"
-LIBEVENT_LIBS=" -L $TOOLCHAIN_LIB_BASE/libevent/libevent-1.4.14b/91ddd43/lib"
+# location of gflags headers and libraries
+GFLAGS_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/gflags/gflags-1.6/91ddd43/include"
+GFLAGS_LIBS=" $TOOLCHAIN_LIB_BASE/gflags/gflags-1.6/91ddd43/lib/libgflags.a"
+
+# location of bzip headers and libraries
+BZIP_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/bzip2/bzip2-1.0.6/91ddd43/include"
+BZIP_LIBS=" $TOOLCHAIN_LIB_BASE/bzip2/bzip2-1.0.6/91ddd43/lib/libbz2.a"
+
+# location of gflags headers and libraries
+GFLAGS_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/gflags/gflags-1.6/91ddd43/include"
+GFLAGS_LIBS=" $TOOLCHAIN_LIB_BASE/gflags/gflags-1.6/91ddd43/lib/libgflags.a"
 
 # use Intel SSE support for checksum calculations
 export USE_SSE=" -msse -msse4.2 "
 
-CC="$TOOLCHAIN_EXECUTABLES/clang/clang-3.1/6ca8a59/bin/clang $CLANG_INCLUDES"
-CXX="$TOOLCHAIN_EXECUTABLES/clang/clang-3.1/6ca8a59/bin/clang++ $CLANG_INCLUDES $JINCLUDE $SNAPPY_INCLUDE $THRIFT_INCLUDE $LIBEVENT_INCLUDE"
+CC="$TOOLCHAIN_EXECUTABLES/clang/clang-3.2/0b7c69d/bin/clang $CLANG_INCLUDES"
+CXX="$TOOLCHAIN_EXECUTABLES/clang/clang-3.2/0b7c69d/bin/clang++ $CLANG_INCLUDES $JINCLUDE $SNAPPY_INCLUDE $ZLIB_INCLUDE $BZIP_INCLUDE $GFLAGS_INCLUDE"
 AR=$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin/ar
 RANLIB=$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin/ranlib
 
-CFLAGS="-B$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin -nostdlib -nostdinc -isystem $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/include/c++/4.7.1 -isystem $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/include/c++/4.7.1/x86_64-facebook-linux -isystem $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/include/c++/4.7.1/backward -isystem $TOOLCHAIN_LIB_BASE/glibc/glibc-2.14.1/99df8fc/include -isystem $TOOLCHAIN_LIB_BASE/clang/clang-3.1/c8f7279/lib/clang/3.1/include -isystem $TOOLCHAIN_LIB_BASE/kernel-headers/kernel-headers-3.2.18_70_fbk11_00129_gc8882d0/da39a3e/include/linux -isystem $TOOLCHAIN_LIB_BASE/kernel-headers/kernel-headers-3.2.18_70_fbk11_00129_gc8882d0/da39a3e/include -Wall -Wno-sign-compare -Wno-unused-variable -Winvalid-pch -Wno-deprecated -Woverloaded-virtual"
-CXXFLAGS="$CFLAGS -nostdinc++ -std=gnu++0x"
+CFLAGS="-B$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin -nostdlib "
+CFLAGS+=" -nostdinc -isystem $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/include/c++/4.7.1 "
+CFLAGS+=" -isystem $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/include/c++/4.7.1/x86_64-facebook-linux "
+CFLAGS+=" -isystem $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/include/c++/4.7.1/backward "
+CFLAGS+=" -isystem $TOOLCHAIN_LIB_BASE/glibc/glibc-2.14.1/99df8fc/include "
+CFLAGS+=" -isystem $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/include "
+CFLAGS+=" -isystem $TOOLCHAIN_LIB_BASE/clang/clang-3.2/0b7c69d/lib/clang/3.2/include "
+CFLAGS+=" -isystem $TOOLCHAIN_LIB_BASE/kernel-headers/kernel-headers-3.2.18_70_fbk11_00129_gc8882d0/da39a3e/include/linux "
+CFLAGS+=" -isystem $TOOLCHAIN_LIB_BASE/kernel-headers/kernel-headers-3.2.18_70_fbk11_00129_gc8882d0/da39a3e/include "
+CFLAGS+=" -Wall -Wno-sign-compare -Wno-unused-variable -Winvalid-pch -Wno-deprecated -Woverloaded-virtual"
+CFLAGS+=" $LIBGCC_INCLUDE $GLIBC_INCLUDE"
+CXXFLAGS="$CFLAGS -nostdinc++"
 
 CFLAGS+=" -I $TOOLCHAIN_LIB_BASE/jemalloc/$TOOL_JEMALLOC/include -DHAVE_JEMALLOC"
 
 EXEC_LDFLAGS=" -Wl,--whole-archive $TOOLCHAIN_LIB_BASE/jemalloc/$TOOL_JEMALLOC/lib/libjemalloc.a"
-EXEC_LDFLAGS+=" -Wl,--no-whole-archive $TOOLCHAIN_LIB_BASE/libunwind/libunwind-1.0.1/91ddd43/lib/libunwind.a"
-EXEC_LDFLAGS+=" $HDFSLIB $SNAPPY_LIBS $THRIFT_LIBS $LIBEVENT_LIBS"
+EXEC_LDFLAGS+=" -Wl,--no-whole-archive $TOOLCHAIN_LIB_BASE/libunwind/libunwind-1.0.1/350336c/lib/libunwind.a"
+EXEC_LDFLAGS+=" $HDFSLIB $SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $GFLAGS_LIBS"
 EXEC_LDFLAGS+=" -Wl,--dynamic-linker,$GLIBC_RUNTIME_PATH/lib/ld-linux-x86-64.so.2"
 EXEC_LDFLAGS+=" -B$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin"
 
-PLATFORM_LDFLAGS="-L$TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/lib -L$TOOLCHAIN_LIB_BASE/glibc/glibc-2.14.1/99df8fc/lib"
+PLATFORM_LDFLAGS="$LIBGCC_LIBS $GLIBC_LIBS "
 
-EXEC_LDFLAGS_SHARED="$SNAPPY_LIBS"
-SNAPPY_LDFLAGS="$SNAPPY_LIBS"
+EXEC_LDFLAGS_SHARED="$SNAPPY_LIBS $ZLIB_LIBS $GFLAGS_LIBS"
 
-export CC CXX AR RANLIB CFLAGS EXEC_LDFLAGS EXEC_LDFLAGS_SHARED SNAPPY_LDFLAGS
+export CC CXX AR RANLIB CFLAGS EXEC_LDFLAGS EXEC_LDFLAGS_SHARED 

build_tools/fbcode.gcc471.sh

@@ -4,10 +4,10 @@
 # fbcode settings.  It uses the latest g++ compiler and also
 # uses jemalloc
 
-TOOLCHAIN_REV=83eb773e262fa705eaebbf3de40db71d53fabf2e
+TOOLCHAIN_REV=fbe3b095a4cc4a3713730050d182b7b4a80c342f
 TOOLCHAIN_EXECUTABLES="/mnt/gvfs/third-party/$TOOLCHAIN_REV/centos5.2-native"
 TOOLCHAIN_LIB_BASE="/mnt/gvfs/third-party/$TOOLCHAIN_REV/gcc-4.7.1-glibc-2.14.1"
-TOOL_JEMALLOC=jemalloc-3.3.1/2f45f3a
+TOOL_JEMALLOC=jemalloc-3.3.1/9202ce3
 
 # location of libhdfs libraries
 if test "$USE_HDFS"; then
@@ -15,10 +15,18 @@ if test "$USE_HDFS"; then
   JINCLUDE="-I$JAVA_HOME/include -I$JAVA_HOME/include/linux"
   GLIBC_RUNTIME_PATH="/usr/local/fbcode/gcc-4.7.1-glibc-2.14.1"
   HDFSLIB=" -Wl,--no-whole-archive hdfs/libhdfs.a -L$JAVA_HOME/jre/lib/amd64 "
-  HDFSLIB+=" -L$JAVA_HOME/jre/lib/amd64/server -L$GLIBC_RUNTIME_PATH/lib " 
+  HDFSLIB+=" -L$JAVA_HOME/jre/lib/amd64/server -L$GLIBC_RUNTIME_PATH/lib "
   HDFSLIB+=" -ldl -lverify -ljava -ljvm "
 fi
 
+# location of libgcc
+LIBGCC_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/include"
+LIBGCC_LIBS=" -L $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/libs"
+
+# location of glibc
+GLIBC_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/glibc/glibc-2.14.1/99df8fc/include"
+GLIBC_LIBS=" -L $TOOLCHAIN_LIB_BASE/glibc/glibc-2.14.1/99df8fc/lib"
+
 # location of snappy headers and libraries
 SNAPPY_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/snappy/snappy-1.0.3/7518bbe/include"
 SNAPPY_LIBS=" $TOOLCHAIN_LIB_BASE/snappy/snappy-1.0.3/7518bbe/lib/libsnappy.a"
@@ -27,35 +35,36 @@ SNAPPY_LIBS=" $TOOLCHAIN_LIB_BASE/snappy/snappy-1.0.3/7518bbe/lib/libsnappy.a"
 ZLIB_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/zlib/zlib-1.2.5/91ddd43/include"
 ZLIB_LIBS=" $TOOLCHAIN_LIB_BASE/zlib/zlib-1.2.5/91ddd43/lib/libz.a"
 
-# location of boost headers and libraries
-THRIFT_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/boost/boost-1.48.0/2a0840d/include"
-THRIFT_INCLUDE+=" -I./thrift -I./thrift/gen-cpp -I./thrift/lib/cpp"
-THRIFT_LIBS=" -L $TOOLCHAIN_LIB_BASE/boost/boost-1.48.0/2a0840d/lib"
+# location of bzip headers and libraries
+BZIP_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/bzip2/bzip2-1.0.6/91ddd43/include"
+BZIP_LIBS=" $TOOLCHAIN_LIB_BASE/bzip2/bzip2-1.0.6/91ddd43/lib/libbz2.a"
 
-# location of libevent
-LIBEVENT_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/libevent/libevent-1.4.14b/91ddd43/include"
-LIBEVENT_LIBS=" -L $TOOLCHAIN_LIB_BASE/libevent/libevent-1.4.14b/91ddd43/lib"
+# location of gflags headers and libraries
+GFLAGS_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/gflags/gflags-1.6/91ddd43/include"
+GFLAGS_LIBS=" $TOOLCHAIN_LIB_BASE/gflags/gflags-1.6/91ddd43/lib/libgflags.a"
 
 # use Intel SSE support for checksum calculations
 export USE_SSE=" -msse -msse4.2 "
 
 CC="$TOOLCHAIN_EXECUTABLES/gcc/gcc-4.7.1-glibc-2.14.1/bin/gcc"
-CXX="$TOOLCHAIN_EXECUTABLES/gcc/gcc-4.7.1-glibc-2.14.1/bin/g++ $JINCLUDE $SNAPPY_INCLUDE $ZLIB_INCLUDE $THRIFT_INCLUDE $LIBEVENT_INCLUDE"
+CXX="$TOOLCHAIN_EXECUTABLES/gcc/gcc-4.7.1-glibc-2.14.1/bin/g++ $JINCLUDE $SNAPPY_INCLUDE $ZLIB_INCLUDE $BZIP_INCLUDE $GFLAGS_INCLUDE"
 AR=$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin/ar
 RANLIB=$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin/ranlib
 
-CFLAGS="-B$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/bin/gold -m64 -mtune=generic -fPIC"
+CFLAGS="-B$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin/gold -m64 -mtune=generic"
 CFLAGS+=" -I $TOOLCHAIN_LIB_BASE/jemalloc/$TOOL_JEMALLOC/include -DHAVE_JEMALLOC"
+CFLAGS+=" $LIBGCC_INCLUDE $GLIBC_INCLUDE"
+CFLAGS+=" -DROCKSDB_PLATFORM_POSIX -DROCKSDB_ATOMIC_PRESENT -DROCKSDB_FALLOCATE_PRESENT"
+CFLAGS+=" -DSNAPPY -DGFLAGS=google -DZLIB -DBZIP2"
 
 EXEC_LDFLAGS=" -Wl,--whole-archive $TOOLCHAIN_LIB_BASE/jemalloc/$TOOL_JEMALLOC/lib/libjemalloc.a"
-EXEC_LDFLAGS+=" -Wl,--no-whole-archive $TOOLCHAIN_LIB_BASE/libunwind/libunwind-1.0.1/91ddd43/lib/libunwind.a"
-EXEC_LDFLAGS+=" $HDFSLIB $SNAPPY_LIBS $ZLIB_LIBS $THRIFT_LIBS $LIBEVENT_LIBS"
+EXEC_LDFLAGS+=" -Wl,--no-whole-archive $TOOLCHAIN_LIB_BASE/libunwind/libunwind-1.0.1/350336c/lib/libunwind.a"
+EXEC_LDFLAGS+=" $HDFSLIB $SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $GFLAGS_LIBS"
 
-PLATFORM_LDFLAGS="-L$TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.7.1/afc21dc/lib -L$TOOLCHAIN_LIB_BASE/glibc/glibc-2.14.1/99df8fc/lib"
+PLATFORM_LDFLAGS="$LIBGCC_LIBS $GLIBC_LIBS "
 
-EXEC_LDFLAGS_SHARED="$SNAPPY_LIBS $ZLIB_LIBS"
-SNAPPY_LDFLAGS="$SNAPPY_LIBS $ZLIB_LIBS"
+EXEC_LDFLAGS_SHARED="$SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $GFLAGS_LIBS"
 
 VALGRIND_VER="$TOOLCHAIN_LIB_BASE/valgrind/valgrind-3.8.1/91ddd43/bin/"
 
-export CC CXX AR RANLIB CFLAGS EXEC_LDFLAGS EXEC_LDFLAGS_SHARED SNAPPY_LDFLAGS VALGRIND_VER
+export CC CXX AR RANLIB CFLAGS EXEC_LDFLAGS EXEC_LDFLAGS_SHARED VALGRIND_VER

build_tools/fbcode.gcc481.sh

@@ -0,0 +1,86 @@
+#!/bin/sh
+#
+# Set environment variables so that we can compile rocksdb using
+# fbcode settings.  It uses the latest g++ compiler and also
+# uses jemalloc
+
+TOOLCHAIN_REV=53dc1fe83f84e9145b9ffb81b81aa7f6a49c87cc
+CENTOS_VERSION=`rpm -q --qf "%{VERSION}" $(rpm -q --whatprovides redhat-release)`
+if [ "$CENTOS_VERSION" = "6" ]; then
+  TOOLCHAIN_EXECUTABLES="/mnt/gvfs/third-party/$TOOLCHAIN_REV/centos6-native"
+else
+  TOOLCHAIN_EXECUTABLES="/mnt/gvfs/third-party/$TOOLCHAIN_REV/centos5.2-native"
+fi
+TOOLCHAIN_LIB_BASE="/mnt/gvfs/third-party/$TOOLCHAIN_REV/gcc-4.8.1-glibc-2.17"
+
+# location of libhdfs libraries
+if test "$USE_HDFS"; then
+  JAVA_HOME="/usr/local/jdk-6u22-64"
+  JINCLUDE="-I$JAVA_HOME/include -I$JAVA_HOME/include/linux"
+  GLIBC_RUNTIME_PATH="/usr/local/fbcode/gcc-4.8.1-glibc-2.17"
+  HDFSLIB=" -Wl,--no-whole-archive hdfs/libhdfs.a -L$JAVA_HOME/jre/lib/amd64 "
+  HDFSLIB+=" -L$JAVA_HOME/jre/lib/amd64/server -L$GLIBC_RUNTIME_PATH/lib "
+  HDFSLIB+=" -ldl -lverify -ljava -ljvm "
+fi
+
+# location of libgcc
+LIBGCC_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.8.1/8aac7fc/include"
+LIBGCC_LIBS=" -L $TOOLCHAIN_LIB_BASE/libgcc/libgcc-4.8.1/8aac7fc/libs"
+
+# location of glibc
+GLIBC_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/glibc/glibc-2.17/99df8fc/include"
+GLIBC_LIBS=" -L $TOOLCHAIN_LIB_BASE/glibc/glibc-2.17/99df8fc/lib"
+
+# location of snappy headers and libraries
+SNAPPY_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/snappy/snappy-1.0.3/43d84e2/include"
+SNAPPY_LIBS=" $TOOLCHAIN_LIB_BASE/snappy/snappy-1.0.3/43d84e2/lib/libsnappy.a"
+
+# location of zlib headers and libraries
+ZLIB_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/zlib/zlib-1.2.5/c3f970a/include"
+ZLIB_LIBS=" $TOOLCHAIN_LIB_BASE/zlib/zlib-1.2.5/c3f970a/lib/libz.a"
+
+# location of bzip headers and libraries
+BZIP_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/bzip2/bzip2-1.0.6/c3f970a/include"
+BZIP_LIBS=" $TOOLCHAIN_LIB_BASE/bzip2/bzip2-1.0.6/c3f970a/lib/libbz2.a"
+
+LZ4_REV=065ec7e38fe83329031f6668c43bef83eff5808b
+LZ4_INCLUDE=" -I /mnt/gvfs/third-party2/lz4/$LZ4_REV/r108/gcc-4.8.1-glibc-2.17/c3f970a/include"
+LZ4_LIBS=" /mnt/gvfs/third-party2/lz4/$LZ4_REV/r108/gcc-4.8.1-glibc-2.17/c3f970a/lib/liblz4.a"
+
+# location of gflags headers and libraries
+GFLAGS_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/gflags/gflags-1.6/c3f970a/include"
+GFLAGS_LIBS=" $TOOLCHAIN_LIB_BASE/gflags/gflags-1.6/c3f970a/lib/libgflags.a"
+
+# location of jemalloc
+JEMALLOC_INCLUDE=" -I $TOOLCHAIN_LIB_BASE/jemalloc/jemalloc-3.4.1/4d53c6f/include/"
+JEMALLOC_LIB=" -Wl,--whole-archive $TOOLCHAIN_LIB_BASE/jemalloc/jemalloc-3.4.1/4d53c6f/lib/libjemalloc.a"
+
+# location of numa
+NUMA_REV=829d10dac0230f99cd7e1778869d2adf3da24b65
+NUMA_INCLUDE=" -I /mnt/gvfs/third-party2/numa/$NUMA_REV/2.0.8/gcc-4.8.1-glibc-2.17/c3f970a/include/"
+NUMA_LIB=" /mnt/gvfs/third-party2/numa/$NUMA_REV/2.0.8/gcc-4.8.1-glibc-2.17/c3f970a/lib/libnuma.a"
+
+# use Intel SSE support for checksum calculations
+export USE_SSE=" -msse -msse4.2 "
+
+CC="$TOOLCHAIN_EXECUTABLES/gcc/gcc-4.8.1/cc6c9dc/bin/gcc"
+CXX="$TOOLCHAIN_EXECUTABLES/gcc/gcc-4.8.1/cc6c9dc/bin/g++ $JINCLUDE $SNAPPY_INCLUDE $ZLIB_INCLUDE $BZIP_INCLUDE $LZ4_INCLUDE $GFLAGS_INCLUDE $NUMA_INCLUDE"
+AR=$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin/ar
+RANLIB=$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin/ranlib
+
+CFLAGS="-B$TOOLCHAIN_EXECUTABLES/binutils/binutils-2.21.1/da39a3e/bin/gold -m64 -mtune=generic"
+CFLAGS+=" $LIBGCC_INCLUDE $GLIBC_INCLUDE"
+CFLAGS+=" -DROCKSDB_PLATFORM_POSIX -DROCKSDB_ATOMIC_PRESENT -DROCKSDB_FALLOCATE_PRESENT"
+CFLAGS+=" -DSNAPPY -DGFLAGS=google -DZLIB -DBZIP2 -DLZ4 -DNUMA"
+
+EXEC_LDFLAGS="-Wl,--dynamic-linker,/usr/local/fbcode/gcc-4.8.1-glibc-2.17/lib/ld.so"
+EXEC_LDFLAGS+=" -Wl,--no-whole-archive $TOOLCHAIN_LIB_BASE/libunwind/libunwind-1.0.1/675d945/lib/libunwind.a"
+EXEC_LDFLAGS+=" $HDFSLIB $SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $LZ4_LIBS $GFLAGS_LIBS $NUMA_LIB"
+
+PLATFORM_LDFLAGS="$LIBGCC_LIBS $GLIBC_LIBS "
+
+EXEC_LDFLAGS_SHARED="$SNAPPY_LIBS $ZLIB_LIBS $BZIP_LIBS $LZ4_LIBS $GFLAGS_LIBS"
+
+VALGRIND_VER="$TOOLCHAIN_LIB_BASE/valgrind/valgrind-3.8.1/c3f970a/bin/"
+
+export CC CXX AR RANLIB CFLAGS EXEC_LDFLAGS EXEC_LDFLAGS_SHARED VALGRIND_VER JEMALLOC_LIB JEMALLOC_INCLUDE

build_tools/fbcode_config.sh

@@ -0,0 +1,134 @@
+#!/bin/sh
+#
+# Set environment variables so that we can compile rocksdb using
+# fbcode settings.  It uses the latest g++ and clang compilers and also
+# uses jemalloc
+# Environment variables that change the behavior of this script:
+# PIC_BUILD -- if true, it will only take pic versions of libraries from fbcode. libraries that don't have pic variant will not be included
+
+
+BASEDIR=`dirname $BASH_SOURCE`
+source "$BASEDIR/dependencies.sh"
+
+CFLAGS=""
+
+# libgcc
+LIBGCC_INCLUDE="$LIBGCC_BASE/include/c++/7.3.0"
+LIBGCC_LIBS=" -L $LIBGCC_BASE/lib"
+
+# glibc
+GLIBC_INCLUDE="$GLIBC_BASE/include"
+GLIBC_LIBS=" -L $GLIBC_BASE/lib"
+
+# snappy
+SNAPPY_INCLUDE=" -I $SNAPPY_BASE/include/"
+if test -z $PIC_BUILD; then
+  SNAPPY_LIBS=" $SNAPPY_BASE/lib/libsnappy.a"
+else
+  SNAPPY_LIBS=" $SNAPPY_BASE/lib/libsnappy_pic.a"
+fi
+CFLAGS+=" -DSNAPPY"
+
+if test -z $PIC_BUILD; then
+  # location of zlib headers and libraries
+  ZLIB_INCLUDE=" -I $ZLIB_BASE/include/"
+  ZLIB_LIBS=" $ZLIB_BASE/lib/libz.a"
+  CFLAGS+=" -DZLIB"
+
+  LZ4_INCLUDE=" -I $LZ4_BASE/include/"
+  LZ4_LIBS=" $LZ4_BASE/lib/liblz4.a"
+  CFLAGS+=" -DLZ4"
+fi
+
+# location of gflags headers and libraries
+GFLAGS_INCLUDE=" -I $GFLAGS_BASE/include/"
+if test -z $PIC_BUILD; then
+  GFLAGS_LIBS=" $GFLAGS_BASE/lib/libgflags.a"
+else
+  GFLAGS_LIBS=" $GFLAGS_BASE/lib/libgflags_pic.a"
+fi
+CFLAGS+=" -DGFLAGS=gflags"
+
+# location of jemalloc
+JEMALLOC_INCLUDE=" -I $JEMALLOC_BASE/include/"
+JEMALLOC_LIB=" $JEMALLOC_BASE/lib/libjemalloc.a"
+
+if test -z $PIC_BUILD; then
+  # location of libunwind
+  LIBUNWIND="$LIBUNWIND_BASE/lib/libunwind.a"
+fi
+
+# location of TBB
+TBB_INCLUDE=" -isystem $TBB_BASE/include/"
+if test -z $PIC_BUILD; then
+  TBB_LIBS="$TBB_BASE/lib/libtbb.a"
+else
+  TBB_LIBS="$TBB_BASE/lib/libtbb_pic.a"
+fi
+CFLAGS+=" -DTBB"
+
+# use Intel SSE support for checksum calculations
+export USE_SSE=" -msse -msse4.2 "
+
+BINUTILS="$BINUTILS_BASE/bin"
+AR="$BINUTILS/ar"
+
+DEPS_INCLUDE="$SNAPPY_INCLUDE $ZLIB_INCLUDE $LZ4_INCLUDE $GFLAGS_INCLUDE"
+
+STDLIBS="-L $GCC_BASE/lib64"
+
+CLANG_BIN="$CLANG_BASE/bin"
+CLANG_LIB="$CLANG_BASE/lib"
+CLANG_SRC="$CLANG_BASE/../../src"
+
+CLANG_ANALYZER="$CLANG_BIN/clang++"
+CLANG_SCAN_BUILD="$CLANG_SRC/llvm/tools/clang/tools/scan-build/bin/scan-build"
+
+if [ -z "$USE_CLANG" ]; then
+  # gcc
+  CC="$GCC_BASE/bin/gcc"
+  CXX="$GCC_BASE/bin/g++"
+
+  CFLAGS+=" -B$BINUTILS/gold"
+  CFLAGS+=" -isystem $LIBGCC_INCLUDE"
+  CFLAGS+=" -isystem $GLIBC_INCLUDE"
+  JEMALLOC=1
+else
+  # clang
+  CLANG_INCLUDE="$CLANG_LIB/clang/stable/include"
+  CC="$CLANG_BIN/clang"
+  CXX="$CLANG_BIN/clang++"
+
+  KERNEL_HEADERS_INCLUDE="$KERNEL_HEADERS_BASE/include"
+
+  CFLAGS+=" -B$BINUTILS/gold -nostdinc -nostdlib"
+  CFLAGS+=" -isystem $LIBGCC_BASE/include/c++/7.x "
+  CFLAGS+=" -isystem $LIBGCC_BASE/include/c++/7.x/x86_64-facebook-linux "
+  CFLAGS+=" -isystem $GLIBC_INCLUDE"
+  CFLAGS+=" -isystem $LIBGCC_INCLUDE"
+  CFLAGS+=" -isystem $CLANG_INCLUDE"
+  CFLAGS+=" -isystem $KERNEL_HEADERS_INCLUDE/linux "
+  CFLAGS+=" -isystem $KERNEL_HEADERS_INCLUDE "
+  CFLAGS+=" -Wno-expansion-to-defined "
+  CXXFLAGS="-nostdinc++"
+fi
+
+CFLAGS+=" $DEPS_INCLUDE"
+CFLAGS+=" -DROCKSDB_PLATFORM_POSIX -DROCKSDB_LIB_IO_POSIX -DROCKSDB_FALLOCATE_PRESENT -DROCKSDB_MALLOC_USABLE_SIZE -DROCKSDB_RANGESYNC_PRESENT -DROCKSDB_SCHED_GETCPU_PRESENT -DROCKSDB_SUPPORT_THREAD_LOCAL -DHAVE_SSE42"
+CXXFLAGS+=" $CFLAGS"
+
+EXEC_LDFLAGS=" $SNAPPY_LIBS $ZLIB_LIBS $LZ4_LIBS $ZSTD_LIBS $GFLAGS_LIBS $NUMA_LIB $TBB_LIBS"
+EXEC_LDFLAGS+=" -B$BINUTILS/gold"
+EXEC_LDFLAGS+=" -Wl,--dynamic-linker,/usr/local/fbcode/platform007/lib/ld.so"
+EXEC_LDFLAGS+=" $LIBUNWIND"
+EXEC_LDFLAGS+=" -Wl,-rpath=/usr/local/fbcode/platform007/lib"
+# required by libtbb
+EXEC_LDFLAGS+=" -ldl"
+
+PLATFORM_LDFLAGS="$LIBGCC_LIBS $GLIBC_LIBS $STDLIBS -lgcc -lstdc++"
+
+EXEC_LDFLAGS_SHARED="$SNAPPY_LIBS $ZLIB_LIBS $LZ4_LIBS $ZSTD_LIBS $GFLAGS_LIBS $TBB_LIBS"
+
+VALGRIND_VER="$VALGRIND_BASE/bin/"
+
+export CC CXX AR CFLAGS CXXFLAGS EXEC_LDFLAGS EXEC_LDFLAGS_SHARED VALGRIND_VER JEMALLOC_LIB JEMALLOC_INCLUDE CLANG_ANALYZER CLANG_SCAN_BUILD 

build_tools/format-diff.sh

@@ -0,0 +1,107 @@
+#!/bin/bash
+# If clang_format_diff.py command is not specfied, we assume we are able to
+# access directly without any path.
+if [ -z $CLANG_FORMAT_DIFF ]
+then
+CLANG_FORMAT_DIFF="clang-format-diff.py"
+fi
+
+# Check clang-format-diff.py
+if ! which $CLANG_FORMAT_DIFF &> /dev/null
+then
+  echo "You didn't have clang-format-diff.py available in your computer!"
+  echo "You can download it by running: "
+  echo "    curl http://goo.gl/iUW1u2"
+  exit 128
+fi
+
+# Check argparse, a library that clang-format-diff.py requires.
+python 2>/dev/null << EOF
+import argparse
+EOF
+
+if [ "$?" != 0 ]
+then
+  echo "To run clang-format-diff.py, we'll need the library "argparse" to be"
+  echo "installed. You can try either of the follow ways to install it:"
+  echo "  1. Manually download argparse: https://pypi.python.org/pypi/argparse"
+  echo "  2. easy_install argparse (if you have easy_install)"
+  echo "  3. pip install argparse (if you have pip)"
+  exit 129
+fi
+
+# TODO(kailiu) following work is not complete since we still need to figure
+# out how to add the modified files done pre-commit hook to git's commit index.
+#
+# Check if this script has already been added to pre-commit hook.
+# Will suggest user to add this script to pre-commit hook if their pre-commit
+# is empty.
+# PRE_COMMIT_SCRIPT_PATH="`git rev-parse --show-toplevel`/.git/hooks/pre-commit"
+# if ! ls $PRE_COMMIT_SCRIPT_PATH &> /dev/null
+# then
+#   echo "Would you like to add this script to pre-commit hook, which will do "
+#   echo -n "the format check for all the affected lines before you check in (y/n):"
+#   read add_to_hook
+#   if [ "$add_to_hook" == "y" ]
+#   then
+#     ln -s `git rev-parse --show-toplevel`/build_tools/format-diff.sh $PRE_COMMIT_SCRIPT_PATH
+#   fi
+# fi
+set -e
+
+uncommitted_code=`git diff HEAD`
+
+# If there's no uncommitted changes, we assume user are doing post-commit
+# format check, in which case we'll check the modified lines from latest commit.
+# Otherwise, we'll check format of the uncommitted code only.
+if [ -z "$uncommitted_code" ]
+then
+  # Check the format of last commit
+  diffs=$(git diff -U0 HEAD^ | $CLANG_FORMAT_DIFF -p 1)
+else
+  # Check the format of uncommitted lines,
+  diffs=$(git diff -U0 HEAD | $CLANG_FORMAT_DIFF -p 1)
+fi
+
+if [ -z "$diffs" ]
+then
+  echo "Nothing needs to be reformatted!"
+  exit 0
+fi
+
+# Highlight the insertion/deletion from the clang-format-diff.py's output
+COLOR_END="\033[0m"
+COLOR_RED="\033[0;31m" 
+COLOR_GREEN="\033[0;32m" 
+
+echo -e "Detect lines that doesn't follow the format rules:\r"
+# Add the color to the diff. lines added will be green; lines removed will be red.
+echo "$diffs" | 
+  sed -e "s/\(^-.*$\)/`echo -e \"$COLOR_RED\1$COLOR_END\"`/" |
+  sed -e "s/\(^+.*$\)/`echo -e \"$COLOR_GREEN\1$COLOR_END\"`/"
+echo -e "Would you like to fix the format automatically (y/n): \c"
+
+# Make sure under any mode, we can read user input.
+exec < /dev/tty
+read to_fix
+
+if [ "$to_fix" != "y" ]
+then
+  exit 1
+fi
+
+# Do in-place format adjustment.
+git diff -U0 HEAD^ | $CLANG_FORMAT_DIFF -i -p 1
+echo "Files reformatted!"
+
+# Amend to last commit if user do the post-commit format check
+if [ -z "$uncommitted_code" ]; then
+  echo -e "Would you like to amend the changes to last commit (`git log HEAD --oneline | head -1`)? (y/n): \c"
+  read to_amend
+
+  if [ "$to_amend" == "y" ]
+  then
+    git commit -a --amend --reuse-message HEAD
+    echo "Amended to last commit"
+  fi
+fi

build_tools/mac-install-gflags.sh

@@ -0,0 +1,25 @@
+#!/bin/sh
+# Install gflags for mac developers.
+
+set -e
+
+DIR=`mktemp -d /tmp/rocksdb_gflags_XXXX`
+
+cd $DIR
+wget https://gflags.googlecode.com/files/gflags-2.0.tar.gz
+tar xvfz gflags-2.0.tar.gz
+cd gflags-2.0
+
+./configure
+make
+make install
+
+# Add include/lib path for g++
+echo 'export LIBRARY_PATH+=":/usr/local/lib"' >> ~/.bash_profile
+echo 'export CPATH+=":/usr/local/include"' >> ~/.bash_profile
+
+echo ""
+echo "-----------------------------------------------------------------------------"
+echo "|                         Installation Completed                            |"
+echo "-----------------------------------------------------------------------------"
+echo "Please run \`. ~/.bash_profile\` to be able to compile with gflags"

build_tools/make_new_version.sh

@@ -0,0 +1,46 @@
+#!/bin/bash
+#  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+#  This source code is licensed under the BSD-style license found in the
+#  LICENSE file in the root directory of this source tree. An additional grant
+#  of patent rights can be found in the PATENTS file in the same directory.
+
+set -e
+if [ -z "$GIT" ]
+then
+  GIT="git"
+fi
+
+# Print out the colored progress info so that it can be brainlessly 
+# distinguished by users.
+function title() {
+  echo -e "\033[1;32m$*\033[0m"
+}
+
+usage="Create new RocksDB version and prepare it for the release process\n"
+usage+="USAGE: ./make_new_version.sh <version>"
+
+# -- Pre-check
+if [[ $# < 1 ]]; then
+  echo -e $usage
+  exit 1
+fi
+
+ROCKSDB_VERSION=$1
+
+GIT_BRANCH=`git rev-parse --abbrev-ref HEAD`
+echo $GIT_BRANCH
+
+if [ $GIT_BRANCH != "master" ]; then
+  echo "Error: Current branch is '$GIT_BRANCH', Please switch to master branch."
+  exit 1
+fi
+
+title "Adding new tag for this release ..."
+BRANCH="$ROCKSDB_VERSION.fb"
+$GIT co -b $BRANCH
+
+# Setting up the proxy for remote repo access
+title "Pushing new branch to remote repo ..."
+git push origin --set-upstream $BRANCH
+
+title "Branch $BRANCH is pushed to github;"

build_tools/regression_build_test.sh

@@ -22,25 +22,26 @@ function cleanup {
   rm -f $STAT_FILE.fillseq
   rm -f $STAT_FILE.readrandom
   rm -f $STAT_FILE.overwrite
+  rm -f $STAT_FILE.memtablefillreadrandom
 }
 
 trap cleanup EXIT
 
-function send_to_ods {
-  key="$1"
-  value="$2"
+if [ -z $GIT_BRANCH ]; then
+  git_br=`git rev-parse --abbrev-ref HEAD`
+else
+  git_br=$(basename $GIT_BRANCH)
+fi
 
-  if [ -z "$value" ];then
-    echo >&2 "ERROR: Key $key doesn't have a value."
-    return
-  fi
-  curl -s "https://www.intern.facebook.com/intern/agent/ods_set.php?entity=rocksdb_build&key=$key&value=$value" \
-    --connect-timeout 60
-}
+if [ $git_br == "master" ]; then
+  git_br=""
+else
+  git_br="."$git_br
+fi
 
-make clean
-make db_bench -j$(nproc)
+make release
 
+# measure fillseq + fill up the DB for overwrite benchmark
 ./db_bench \
     --benchmarks=fillseq \
     --db=$DATA_DIR \
@@ -50,6 +51,7 @@ make db_bench -j$(nproc)
     --writes=$NUM \
     --cache_size=6442450944 \
     --cache_numshardbits=6 \
+    --table_cache_numshardbits=4 \
     --open_files=55000 \
     --statistics=1 \
     --histogram=1 \
@@ -57,15 +59,17 @@ make db_bench -j$(nproc)
     --disable_wal=1 \
     --sync=0  > ${STAT_FILE}.fillseq
 
+# measure overwrite performance
 ./db_bench \
     --benchmarks=overwrite \
     --db=$DATA_DIR \
     --use_existing_db=1 \
     --bloom_bits=10 \
     --num=$NUM \
-    --writes=$((NUM / 2)) \
+    --writes=$((NUM / 10)) \
     --cache_size=6442450944 \
     --cache_numshardbits=6  \
+    --table_cache_numshardbits=4 \
     --open_files=55000 \
     --statistics=1 \
     --histogram=1 \
@@ -74,27 +78,317 @@ make db_bench -j$(nproc)
     --sync=0 \
     --threads=8 > ${STAT_FILE}.overwrite
 
+# fill up the db for readrandom benchmark (1GB total size)
 ./db_bench \
-    --benchmarks=readrandom \
+    --benchmarks=fillseq \
     --db=$DATA_DIR \
-    --use_existing_db=1 \
+    --use_existing_db=0 \
     --bloom_bits=10 \
     --num=$NUM \
-    --reads=$((NUM / 100)) \
+    --writes=$NUM \
     --cache_size=6442450944 \
     --cache_numshardbits=6 \
+    --table_cache_numshardbits=4 \
     --open_files=55000 \
     --statistics=1 \
     --histogram=1 \
     --disable_data_sync=1 \
     --disable_wal=1 \
     --sync=0 \
-    --threads=128 > ${STAT_FILE}.readrandom
+    --threads=1 > /dev/null
 
-OVERWRITE_OPS=$(awk '/overwrite/ {print $5}' $STAT_FILE.overwrite)
-FILLSEQ_OPS=$(awk '/fillseq/ {print $5}' $STAT_FILE.fillseq)
-READRANDOM_OPS=$(awk '/readrandom/ {print $5}' $STAT_FILE.readrandom)
+# measure readrandom with 6GB block cache
+./db_bench \
+    --benchmarks=readrandom \
+    --db=$DATA_DIR \
+    --use_existing_db=1 \
+    --bloom_bits=10 \
+    --num=$NUM \
+    --reads=$((NUM / 5)) \
+    --cache_size=6442450944 \
+    --cache_numshardbits=6 \
+    --table_cache_numshardbits=4 \
+    --open_files=55000 \
+    --statistics=1 \
+    --histogram=1 \
+    --disable_data_sync=1 \
+    --disable_wal=1 \
+    --sync=0 \
+    --threads=16 > ${STAT_FILE}.readrandom
 
-send_to_ods rocksdb.build.overwrite.qps $OVERWRITE_OPS
-send_to_ods rocksdb.build.fillseq.qps $FILLSEQ_OPS
-send_to_ods rocksdb.build.readrandom.qps $READRANDOM_OPS
+# measure readrandom with 6GB block cache and tailing iterator
+./db_bench \
+    --benchmarks=readrandom \
+    --db=$DATA_DIR \
+    --use_existing_db=1 \
+    --bloom_bits=10 \
+    --num=$NUM \
+    --reads=$((NUM / 5)) \
+    --cache_size=6442450944 \
+    --cache_numshardbits=6 \
+    --table_cache_numshardbits=4 \
+    --open_files=55000 \
+    --use_tailing_iterator=1 \
+    --statistics=1 \
+    --histogram=1 \
+    --disable_data_sync=1 \
+    --disable_wal=1 \
+    --sync=0 \
+    --threads=16 > ${STAT_FILE}.readrandomtailing
+
+# measure readrandom with 100MB block cache
+./db_bench \
+    --benchmarks=readrandom \
+    --db=$DATA_DIR \
+    --use_existing_db=1 \
+    --bloom_bits=10 \
+    --num=$NUM \
+    --reads=$((NUM / 5)) \
+    --cache_size=104857600 \
+    --cache_numshardbits=6 \
+    --table_cache_numshardbits=4 \
+    --open_files=55000 \
+    --statistics=1 \
+    --histogram=1 \
+    --disable_data_sync=1 \
+    --disable_wal=1 \
+    --sync=0 \
+    --threads=16 > ${STAT_FILE}.readrandomsmallblockcache
+
+# measure readrandom with 8k data in memtable
+./db_bench \
+    --benchmarks=overwrite,readrandom \
+    --db=$DATA_DIR \
+    --use_existing_db=1 \
+    --bloom_bits=10 \
+    --num=$NUM \
+    --reads=$((NUM / 5)) \
+    --writes=512 \
+    --cache_size=6442450944 \
+    --cache_numshardbits=6 \
+    --table_cache_numshardbits=4 \
+    --write_buffer_size=1000000000 \
+    --open_files=55000 \
+    --statistics=1 \
+    --histogram=1 \
+    --disable_data_sync=1 \
+    --disable_wal=1 \
+    --sync=0 \
+    --threads=16 > ${STAT_FILE}.readrandom_mem_sst
+
+
+# fill up the db for readrandom benchmark with filluniquerandom (1GB total size)
+./db_bench \
+    --benchmarks=filluniquerandom \
+    --db=$DATA_DIR \
+    --use_existing_db=0 \
+    --bloom_bits=10 \
+    --num=$((NUM / 4)) \
+    --writes=$((NUM / 4)) \
+    --cache_size=6442450944 \
+    --cache_numshardbits=6 \
+    --table_cache_numshardbits=4 \
+    --open_files=55000 \
+    --statistics=1 \
+    --histogram=1 \
+    --disable_data_sync=1 \
+    --disable_wal=1 \
+    --sync=0 \
+    --threads=1 > /dev/null
+
+# dummy test just to compact the data
+./db_bench \
+    --benchmarks=readrandom \
+    --db=$DATA_DIR \
+    --use_existing_db=1 \
+    --bloom_bits=10 \
+    --num=$((NUM / 1000)) \
+    --reads=$((NUM / 1000)) \
+    --cache_size=6442450944 \
+    --cache_numshardbits=6 \
+    --table_cache_numshardbits=4 \
+    --open_files=55000 \
+    --statistics=1 \
+    --histogram=1 \
+    --disable_data_sync=1 \
+    --disable_wal=1 \
+    --sync=0 \
+    --threads=16 > /dev/null
+
+# measure readrandom after load with filluniquerandom with 6GB block cache
+./db_bench \
+    --benchmarks=readrandom \
+    --db=$DATA_DIR \
+    --use_existing_db=1 \
+    --bloom_bits=10 \
+    --num=$((NUM / 4)) \
+    --reads=$((NUM / 4)) \
+    --cache_size=6442450944 \
+    --cache_numshardbits=6 \
+    --table_cache_numshardbits=4 \
+    --open_files=55000 \
+    --disable_auto_compactions=1 \
+    --statistics=1 \
+    --histogram=1 \
+    --disable_data_sync=1 \
+    --disable_wal=1 \
+    --sync=0 \
+    --threads=16 > ${STAT_FILE}.readrandom_filluniquerandom
+
+# measure readwhilewriting after load with filluniquerandom with 6GB block cache
+./db_bench \
+    --benchmarks=readwhilewriting \
+    --db=$DATA_DIR \
+    --use_existing_db=1 \
+    --bloom_bits=10 \
+    --num=$((NUM / 4)) \
+    --reads=$((NUM / 4)) \
+    --writes_per_second=1000 \
+    --write_buffer_size=100000000 \
+    --cache_size=6442450944 \
+    --cache_numshardbits=6 \
+    --table_cache_numshardbits=4 \
+    --open_files=55000 \
+    --statistics=1 \
+    --histogram=1 \
+    --disable_data_sync=1 \
+    --disable_wal=1 \
+    --sync=0 \
+    --threads=16 > ${STAT_FILE}.readwhilewriting
+
+# measure memtable performance -- none of the data gets flushed to disk
+./db_bench \
+    --benchmarks=fillrandom,readrandom, \
+    --db=$DATA_DIR \
+    --use_existing_db=0 \
+    --num=$((NUM / 10)) \
+    --reads=$NUM \
+    --cache_size=6442450944 \
+    --cache_numshardbits=6 \
+    --table_cache_numshardbits=4 \
+    --write_buffer_size=1000000000 \
+    --open_files=55000 \
+    --statistics=1 \
+    --histogram=1 \
+    --disable_data_sync=1 \
+    --disable_wal=1 \
+    --sync=0 \
+    --value_size=10 \
+    --threads=16 > ${STAT_FILE}.memtablefillreadrandom
+
+common_in_mem_args="--db=/dev/shm/rocksdb \
+    --num_levels=6 \
+    --key_size=20 \
+    --prefix_size=12 \
+    --keys_per_prefix=10 \
+    --value_size=100 \
+    --compression_type=none \
+    --compression_ratio=1 \
+    --hard_rate_limit=2 \
+    --write_buffer_size=134217728 \
+    --max_write_buffer_number=4 \
+    --level0_file_num_compaction_trigger=8 \
+    --level0_slowdown_writes_trigger=16 \
+    --level0_stop_writes_trigger=24 \
+    --target_file_size_base=134217728 \
+    --max_bytes_for_level_base=1073741824 \
+    --disable_wal=0 \
+    --wal_dir=/dev/shm/rocksdb \
+    --sync=0 \
+    --disable_data_sync=1 \
+    --verify_checksum=1 \
+    --delete_obsolete_files_period_micros=314572800 \
+    --max_grandparent_overlap_factor=10 \
+    --use_plain_table=1 \
+    --open_files=-1 \
+    --mmap_read=1 \
+    --mmap_write=0 \
+    --memtablerep=prefix_hash \
+    --bloom_bits=10 \
+    --bloom_locality=1 \
+    --perf_level=0"
+
+# prepare a in-memory DB with 50M keys, total DB size is ~6G
+./db_bench \
+    $common_in_mem_args \
+    --statistics=0 \
+    --max_background_compactions=16 \
+    --max_background_flushes=16 \
+    --benchmarks=filluniquerandom \
+    --use_existing_db=0 \
+    --num=52428800 \
+    --threads=1 > /dev/null
+
+# Readwhilewriting
+./db_bench \
+    $common_in_mem_args \
+    --statistics=1 \
+    --max_background_compactions=4 \
+    --max_background_flushes=0 \
+    --benchmarks=readwhilewriting\
+    --use_existing_db=1 \
+    --duration=600 \
+    --threads=32 \
+    --writes_per_second=81920 > ${STAT_FILE}.readwhilewriting_in_ram
+
+# Seekrandomwhilewriting
+./db_bench \
+    $common_in_mem_args \
+    --statistics=1 \
+    --max_background_compactions=4 \
+    --max_background_flushes=0 \
+    --benchmarks=seekrandomwhilewriting \
+    --use_existing_db=1 \
+    --use_tailing_iterator=1 \
+    --duration=600 \
+    --threads=32 \
+    --writes_per_second=81920 > ${STAT_FILE}.seekwhilewriting_in_ram
+
+
+# send data to ods
+function send_to_ods {
+  key="$1"
+  value="$2"
+
+  if [ -z $JENKINS_HOME ]; then
+    # running on devbox, just print out the values
+    echo $1 $2
+    return
+  fi
+
+  if [ -z "$value" ];then
+    echo >&2 "ERROR: Key $key doesn't have a value."
+    return
+  fi
+  curl -s "https://www.intern.facebook.com/intern/agent/ods_set.php?entity=rocksdb_build$git_br&key=$key&value=$value" \
+    --connect-timeout 60
+}
+
+function send_benchmark_to_ods {
+  bench="$1"
+  bench_key="$2"
+  file="$3"
+
+  QPS=$(grep $bench $file | awk '{print $5}')
+  P50_MICROS=$(grep $bench $file -A 6 | grep "Percentiles" | awk '{print $3}' )
+  P75_MICROS=$(grep $bench $file -A 6 | grep "Percentiles" | awk '{print $5}' )
+  P99_MICROS=$(grep $bench $file -A 6 | grep "Percentiles" | awk '{print $7}' )
+
+  send_to_ods rocksdb.build.$bench_key.qps $QPS
+  send_to_ods rocksdb.build.$bench_key.p50_micros $P50_MICROS
+  send_to_ods rocksdb.build.$bench_key.p75_micros $P75_MICROS
+  send_to_ods rocksdb.build.$bench_key.p99_micros $P99_MICROS
+}
+
+send_benchmark_to_ods overwrite overwrite $STAT_FILE.overwrite
+send_benchmark_to_ods fillseq fillseq $STAT_FILE.fillseq
+send_benchmark_to_ods readrandom readrandom $STAT_FILE.readrandom
+send_benchmark_to_ods readrandom readrandom_tailing $STAT_FILE.readrandomtailing
+send_benchmark_to_ods readrandom readrandom_smallblockcache $STAT_FILE.readrandomsmallblockcache
+send_benchmark_to_ods readrandom readrandom_memtable_sst $STAT_FILE.readrandom_mem_sst
+send_benchmark_to_ods readrandom readrandom_fillunique_random $STAT_FILE.readrandom_filluniquerandom
+send_benchmark_to_ods fillrandom memtablefillrandom $STAT_FILE.memtablefillreadrandom
+send_benchmark_to_ods readrandom memtablereadrandom $STAT_FILE.memtablefillreadrandom
+send_benchmark_to_ods readwhilewriting readwhilewriting $STAT_FILE.readwhilewriting
+send_benchmark_to_ods readwhilewriting readwhilewriting_in_ram ${STAT_FILE}.readwhilewriting_in_ram
+send_benchmark_to_ods seekrandomwhilewriting seekwhilewriting_in_ram ${STAT_FILE}.seekwhilewriting_in_ram

coverage/coverage_test.sh

@@ -44,6 +44,11 @@ $GCOV --preserve-paths --relative-only --no-output $GCNO_FILES 2>/dev/null |
   tee -a $RECENT_REPORT &&
 echo -e "Generated coverage report for recently updated files: $RECENT_REPORT\n"
 
+# Unless otherwise specified, we'll not generate html report by default
+if [ -z "$HTML" ]; then
+  exit 0
+fi
+
 # Generate the html report. If we cannot find lcov in this machine, we'll simply
 # skip this step.
 echo "Generating the html coverage report..."

db/builder.cc

@@ -1,33 +1,49 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
 #include "db/builder.h"
 
-#include "db/filename.h"
 #include "db/dbformat.h"
+#include "db/filename.h"
 #include "db/merge_helper.h"
 #include "db/table_cache.h"
 #include "db/version_edit.h"
 #include "rocksdb/db.h"
 #include "rocksdb/env.h"
 #include "rocksdb/iterator.h"
+#include "rocksdb/options.h"
+#include "rocksdb/table.h"
+#include "table/block_based_table_builder.h"
 #include "util/stop_watch.h"
 
 namespace rocksdb {
 
-Status BuildTable(const std::string& dbname,
-                  Env* env,
-                  const Options& options,
-                  const EnvOptions& soptions,
-                  TableCache* table_cache,
-                  Iterator* iter,
-                  FileMetaData* meta,
-                  const Comparator* user_comparator,
+class TableFactory;
+
+TableBuilder* NewTableBuilder(const Options& options,
+                              const InternalKeyComparator& internal_comparator,
+                              WritableFile* file,
+                              CompressionType compression_type) {
+  return options.table_factory->NewTableBuilder(options, internal_comparator,
+                                                file, compression_type);
+}
+
+Status BuildTable(const std::string& dbname, Env* env, const Options& options,
+                  const EnvOptions& soptions, TableCache* table_cache,
+                  Iterator* iter, FileMetaData* meta,
+                  const InternalKeyComparator& internal_comparator,
                   const SequenceNumber newest_snapshot,
-                  const SequenceNumber earliest_seqno_in_memtable) {
+                  const SequenceNumber earliest_seqno_in_memtable,
+                  const CompressionType compression,
+                  const Env::IOPriority io_priority) {
   Status s;
-  meta->file_size = 0;
+  meta->fd.file_size = 0;
   meta->smallest_seqno = meta->largest_seqno = 0;
   iter->SeekToFirst();
 
@@ -39,14 +55,18 @@ Status BuildTable(const std::string& dbname,
     purge = false;
   }
 
-  std::string fname = TableFileName(dbname, meta->number);
+  std::string fname = TableFileName(options.db_paths, meta->fd.GetNumber(),
+                                    meta->fd.GetPathId());
   if (iter->Valid()) {
     unique_ptr<WritableFile> file;
     s = env->NewWritableFile(fname, &file, soptions);
     if (!s.ok()) {
       return s;
     }
-    TableBuilder* builder = new TableBuilder(options, file.get(), 0);
+    file->SetIOPriority(io_priority);
+
+    TableBuilder* builder =
+        NewTableBuilder(options, internal_comparator, file.get(), compression);
 
     // the first key is the smallest key
     Slice key = iter->key();
@@ -54,8 +74,9 @@ Status BuildTable(const std::string& dbname,
     meta->smallest_seqno = GetInternalKeySeqno(key);
     meta->largest_seqno = meta->smallest_seqno;
 
-    MergeHelper merge(user_comparator, options.merge_operator.get(),
-                      options.info_log.get(),
+    MergeHelper merge(internal_comparator.user_comparator(),
+                      options.merge_operator.get(), options.info_log.get(),
+                      options.min_partial_merge_operands,
                       true /* internal key corruption is not ok */);
 
     if (purge) {
@@ -84,8 +105,8 @@ Status BuildTable(const std::string& dbname,
         // If the key is the same as the previous key (and it is not the
         // first key), then we skip it, since it is an older version.
         // Otherwise we output the key and mark it as the "new" previous key.
-        if (!is_first_key && !user_comparator->Compare(prev_ikey.user_key,
-                                                       this_ikey.user_key)) {
+        if (!is_first_key && !internal_comparator.user_comparator()->Compare(
+                                  prev_ikey.user_key, this_ikey.user_key)) {
           // seqno within the same key are in decreasing order
           assert(this_ikey.sequence < prev_ikey.sequence);
         } else {
@@ -93,6 +114,7 @@ Status BuildTable(const std::string& dbname,
 
           if (this_ikey.type == kTypeMerge) {
             // Handle merge-type keys using the MergeHelper
+            // TODO: pass statistics to MergeUntil
             merge.MergeUntil(iter, 0 /* don't worry about snapshot */);
             iterator_at_next = true;
             if (merge.IsSuccess()) {
@@ -158,8 +180,8 @@ Status BuildTable(const std::string& dbname,
     if (s.ok()) {
       s = builder->Finish();
       if (s.ok()) {
-        meta->file_size = builder->FileSize();
-        assert(meta->file_size > 0);
+        meta->fd.file_size = builder->FileSize();
+        assert(meta->fd.GetFileSize() > 0);
       }
     } else {
       builder->Abandon();
@@ -169,10 +191,10 @@ Status BuildTable(const std::string& dbname,
     // Finish and check for file errors
     if (s.ok() && !options.disableDataSync) {
       if (options.use_fsync) {
-        StopWatch sw(env, options.statistics, TABLE_SYNC_MICROS);
+        StopWatch sw(env, options.statistics.get(), TABLE_SYNC_MICROS);
         s = file->Fsync();
       } else {
-        StopWatch sw(env, options.statistics, TABLE_SYNC_MICROS);
+        StopWatch sw(env, options.statistics.get(), TABLE_SYNC_MICROS);
         s = file->Sync();
       }
     }
@@ -182,10 +204,8 @@ Status BuildTable(const std::string& dbname,
 
     if (s.ok()) {
       // Verify that the table is usable
-      Iterator* it = table_cache->NewIterator(ReadOptions(),
-                                              soptions,
-                                              meta->number,
-                                              meta->file_size);
+      Iterator* it = table_cache->NewIterator(ReadOptions(), soptions,
+                                              internal_comparator, meta->fd);
       s = it->status();
       delete it;
     }
@@ -196,7 +216,7 @@ Status BuildTable(const std::string& dbname,
     s = iter->status();
   }
 
-  if (s.ok() && meta->file_size > 0) {
+  if (s.ok() && meta->fd.GetFileSize() > 0) {
     // Keep it
   } else {
     env->DeleteFile(fname);

db/builder.h

@@ -1,13 +1,16 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
-
-#ifndef STORAGE_LEVELDB_DB_BUILDER_H_
-#define STORAGE_LEVELDB_DB_BUILDER_H_
-
+#pragma once
 #include "rocksdb/comparator.h"
+#include "rocksdb/env.h"
 #include "rocksdb/status.h"
 #include "rocksdb/types.h"
+#include "rocksdb/options.h"
 
 namespace rocksdb {
 
@@ -15,27 +18,30 @@ struct Options;
 struct FileMetaData;
 
 class Env;
-class EnvOptions;
+struct EnvOptions;
 class Iterator;
 class TableCache;
 class VersionEdit;
+class TableBuilder;
+class WritableFile;
+
+extern TableBuilder* NewTableBuilder(
+    const Options& options, const InternalKeyComparator& internal_comparator,
+    WritableFile* file, CompressionType compression_type);
 
 // Build a Table file from the contents of *iter.  The generated file
-// will be named according to meta->number.  On success, the rest of
+// will be named according to number specified in meta. On success, the rest of
 // *meta will be filled with metadata about the generated table.
 // If no data is present in *iter, meta->file_size will be set to
 // zero, and no Table file will be produced.
-extern Status BuildTable(const std::string& dbname,
-                         Env* env,
-                         const Options& options,
-                         const EnvOptions& soptions,
-                         TableCache* table_cache,
-                         Iterator* iter,
+extern Status BuildTable(const std::string& dbname, Env* env,
+                         const Options& options, const EnvOptions& soptions,
+                         TableCache* table_cache, Iterator* iter,
                          FileMetaData* meta,
-                         const Comparator* user_comparator,
+                         const InternalKeyComparator& internal_comparator,
                          const SequenceNumber newest_snapshot,
-                         const SequenceNumber earliest_seqno_in_memtable);
+                         const SequenceNumber earliest_seqno_in_memtable,
+                         const CompressionType compression,
+                         const Env::IOPriority io_priority = Env::IO_HIGH);
 
 }  // namespace rocksdb
-
-#endif  // STORAGE_LEVELDB_DB_BUILDER_H_

db/c_test.c

@@ -62,30 +62,46 @@ static void Free(char** ptr) {
 }
 
 static void CheckGet(
-    leveldb_t* db,
-    const leveldb_readoptions_t* options,
+    rocksdb_t* db,
+    const rocksdb_readoptions_t* options,
     const char* key,
     const char* expected) {
   char* err = NULL;
   size_t val_len;
   char* val;
-  val = leveldb_get(db, options, key, strlen(key), &val_len, &err);
+  val = rocksdb_get(db, options, key, strlen(key), &val_len, &err);
   CheckNoError(err);
   CheckEqual(expected, val, val_len);
   Free(&val);
 }
 
-static void CheckIter(leveldb_iterator_t* iter,
+static void CheckGetCF(
+    rocksdb_t* db,
+    const rocksdb_readoptions_t* options,
+    rocksdb_column_family_handle_t* handle,
+    const char* key,
+    const char* expected) {
+  char* err = NULL;
+  size_t val_len;
+  char* val;
+  val = rocksdb_get_cf(db, options, handle, key, strlen(key), &val_len, &err);
+  CheckNoError(err);
+  CheckEqual(expected, val, val_len);
+  Free(&val);
+}
+
+
+static void CheckIter(rocksdb_iterator_t* iter,
                       const char* key, const char* val) {
   size_t len;
   const char* str;
-  str = leveldb_iter_key(iter, &len);
+  str = rocksdb_iter_key(iter, &len);
   CheckEqual(key, str, len);
-  str = leveldb_iter_value(iter, &len);
+  str = rocksdb_iter_value(iter, &len);
   CheckEqual(val, str, len);
 }
 
-// Callback from leveldb_writebatch_iterate()
+// Callback from rocksdb_writebatch_iterate()
 static void CheckPut(void* ptr,
                      const char* k, size_t klen,
                      const char* v, size_t vlen) {
@@ -104,7 +120,7 @@ static void CheckPut(void* ptr,
   (*state)++;
 }
 
-// Callback from leveldb_writebatch_iterate()
+// Callback from rocksdb_writebatch_iterate()
 static void CheckDel(void* ptr, const char* k, size_t klen) {
   int* state = (int*) ptr;
   CheckCondition(*state == 2);
@@ -145,7 +161,7 @@ static char* FilterCreate(
   memcpy(result, "fake", 4);
   return result;
 }
-unsigned char FilterKeyMatch(
+static unsigned char FilterKeyMatch(
     void* arg,
     const char* key, size_t length,
     const char* filter, size_t filter_length) {
@@ -154,118 +170,222 @@ unsigned char FilterKeyMatch(
   return fake_filter_result;
 }
 
+// Custom compaction filter
+static void CFilterDestroy(void* arg) {}
+static const char* CFilterName(void* arg) { return "foo"; }
+static unsigned char CFilterFilter(void* arg, int level, const char* key,
+                                   size_t key_length,
+                                   const char* existing_value,
+                                   size_t value_length, char** new_value,
+                                   size_t* new_value_length,
+                                   unsigned char* value_changed) {
+  if (key_length == 3) {
+    if (memcmp(key, "bar", key_length) == 0) {
+      return 1;
+    } else if (memcmp(key, "baz", key_length) == 0) {
+      *value_changed = 1;
+      *new_value = "newbazvalue";
+      *new_value_length = 11;
+      return 0;
+    }
+  }
+  return 0;
+}
+
+static void CFilterFactoryDestroy(void* arg) {}
+static const char* CFilterFactoryName(void* arg) { return "foo"; }
+static rocksdb_compactionfilter_t* CFilterCreate(
+    void* arg, rocksdb_compactionfiltercontext_t* context) {
+  return rocksdb_compactionfilter_create(NULL, CFilterDestroy, CFilterFilter,
+                                         CFilterName);
+}
+
+static rocksdb_t* CheckCompaction(rocksdb_t* db, rocksdb_options_t* options,
+                                  rocksdb_readoptions_t* roptions,
+                                  rocksdb_writeoptions_t* woptions) {
+  char* err = NULL;
+  db = rocksdb_open(options, dbname, &err);
+  CheckNoError(err);
+  rocksdb_put(db, woptions, "foo", 3, "foovalue", 8, &err);
+  CheckNoError(err);
+  CheckGet(db, roptions, "foo", "foovalue");
+  rocksdb_put(db, woptions, "bar", 3, "barvalue", 8, &err);
+  CheckNoError(err);
+  CheckGet(db, roptions, "bar", "barvalue");
+  rocksdb_put(db, woptions, "baz", 3, "bazvalue", 8, &err);
+  CheckNoError(err);
+  CheckGet(db, roptions, "baz", "bazvalue");
+
+  // Force compaction
+  rocksdb_compact_range(db, NULL, 0, NULL, 0);
+  // should have filtered bar, but not foo
+  CheckGet(db, roptions, "foo", "foovalue");
+  CheckGet(db, roptions, "bar", NULL);
+  CheckGet(db, roptions, "baz", "newbazvalue");
+  return db;
+}
+
+// Custom merge operator
+static void MergeOperatorDestroy(void* arg) { }
+static const char* MergeOperatorName(void* arg) {
+  return "TestMergeOperator";
+}
+static char* MergeOperatorFullMerge(
+    void* arg,
+    const char* key, size_t key_length,
+    const char* existing_value, size_t existing_value_length,
+    const char* const* operands_list, const size_t* operands_list_length,
+    int num_operands,
+    unsigned char* success, size_t* new_value_length) {
+  *new_value_length = 4;
+  *success = 1;
+  char* result = malloc(4);
+  memcpy(result, "fake", 4);
+  return result;
+}
+static char* MergeOperatorPartialMerge(
+    void* arg,
+    const char* key, size_t key_length,
+    const char* const* operands_list, const size_t* operands_list_length,
+    int num_operands,
+    unsigned char* success, size_t* new_value_length) {
+  *new_value_length = 4;
+  *success = 1;
+  char* result = malloc(4);
+  memcpy(result, "fake", 4);
+  return result;
+}
+
 int main(int argc, char** argv) {
-  leveldb_t* db;
-  leveldb_comparator_t* cmp;
-  leveldb_cache_t* cache;
-  leveldb_env_t* env;
-  leveldb_options_t* options;
-  leveldb_readoptions_t* roptions;
-  leveldb_writeoptions_t* woptions;
+  rocksdb_t* db;
+  rocksdb_comparator_t* cmp;
+  rocksdb_cache_t* cache;
+  rocksdb_env_t* env;
+  rocksdb_options_t* options;
+  rocksdb_readoptions_t* roptions;
+  rocksdb_writeoptions_t* woptions;
   char* err = NULL;
   int run = -1;
 
   snprintf(dbname, sizeof(dbname),
-           "%s/leveldb_c_test-%d",
+           "%s/rocksdb_c_test-%d",
            GetTempDir(),
            ((int) geteuid()));
 
   StartPhase("create_objects");
-  cmp = leveldb_comparator_create(NULL, CmpDestroy, CmpCompare, CmpName);
-  env = leveldb_create_default_env();
-  cache = leveldb_cache_create_lru(100000);
+  cmp = rocksdb_comparator_create(NULL, CmpDestroy, CmpCompare, CmpName);
+  env = rocksdb_create_default_env();
+  cache = rocksdb_cache_create_lru(100000);
 
-  options = leveldb_options_create();
-  leveldb_options_set_comparator(options, cmp);
-  leveldb_options_set_error_if_exists(options, 1);
-  leveldb_options_set_cache(options, cache);
-  leveldb_options_set_env(options, env);
-  leveldb_options_set_info_log(options, NULL);
-  leveldb_options_set_write_buffer_size(options, 100000);
-  leveldb_options_set_paranoid_checks(options, 1);
-  leveldb_options_set_max_open_files(options, 10);
-  leveldb_options_set_block_size(options, 1024);
-  leveldb_options_set_block_restart_interval(options, 8);
-  leveldb_options_set_compression(options, leveldb_no_compression);
-  leveldb_options_set_compression_options(options, -14, -1, 0);
-  int compression_levels[] = {leveldb_no_compression, leveldb_no_compression,
-                              leveldb_no_compression, leveldb_no_compression};
-  leveldb_options_set_compression_per_level(options, compression_levels, 4);
+  options = rocksdb_options_create();
+  rocksdb_options_set_comparator(options, cmp);
+  rocksdb_options_set_error_if_exists(options, 1);
+  rocksdb_options_set_cache(options, cache);
+  rocksdb_options_set_env(options, env);
+  rocksdb_options_set_info_log(options, NULL);
+  rocksdb_options_set_write_buffer_size(options, 100000);
+  rocksdb_options_set_paranoid_checks(options, 1);
+  rocksdb_options_set_max_open_files(options, 10);
+  rocksdb_options_set_block_size(options, 1024);
+  rocksdb_options_set_block_restart_interval(options, 8);
+  rocksdb_options_set_compression(options, rocksdb_no_compression);
+  rocksdb_options_set_compression_options(options, -14, -1, 0);
+  int compression_levels[] = {rocksdb_no_compression, rocksdb_no_compression,
+                              rocksdb_no_compression, rocksdb_no_compression};
+  rocksdb_options_set_compression_per_level(options, compression_levels, 4);
 
-  roptions = leveldb_readoptions_create();
-  leveldb_readoptions_set_verify_checksums(roptions, 1);
-  leveldb_readoptions_set_fill_cache(roptions, 0);
+  roptions = rocksdb_readoptions_create();
+  rocksdb_readoptions_set_verify_checksums(roptions, 1);
+  rocksdb_readoptions_set_fill_cache(roptions, 0);
 
-  woptions = leveldb_writeoptions_create();
-  leveldb_writeoptions_set_sync(woptions, 1);
+  woptions = rocksdb_writeoptions_create();
+  rocksdb_writeoptions_set_sync(woptions, 1);
 
   StartPhase("destroy");
-  leveldb_destroy_db(options, dbname, &err);
+  rocksdb_destroy_db(options, dbname, &err);
   Free(&err);
 
   StartPhase("open_error");
-  db = leveldb_open(options, dbname, &err);
+  db = rocksdb_open(options, dbname, &err);
   CheckCondition(err != NULL);
   Free(&err);
 
   StartPhase("open");
-  leveldb_options_set_create_if_missing(options, 1);
-  db = leveldb_open(options, dbname, &err);
+  rocksdb_options_set_create_if_missing(options, 1);
+  db = rocksdb_open(options, dbname, &err);
   CheckNoError(err);
   CheckGet(db, roptions, "foo", NULL);
 
   StartPhase("put");
-  leveldb_put(db, woptions, "foo", 3, "hello", 5, &err);
+  rocksdb_put(db, woptions, "foo", 3, "hello", 5, &err);
   CheckNoError(err);
   CheckGet(db, roptions, "foo", "hello");
 
   StartPhase("compactall");
-  leveldb_compact_range(db, NULL, 0, NULL, 0);
+  rocksdb_compact_range(db, NULL, 0, NULL, 0);
   CheckGet(db, roptions, "foo", "hello");
 
   StartPhase("compactrange");
-  leveldb_compact_range(db, "a", 1, "z", 1);
+  rocksdb_compact_range(db, "a", 1, "z", 1);
   CheckGet(db, roptions, "foo", "hello");
 
   StartPhase("writebatch");
   {
-    leveldb_writebatch_t* wb = leveldb_writebatch_create();
-    leveldb_writebatch_put(wb, "foo", 3, "a", 1);
-    leveldb_writebatch_clear(wb);
-    leveldb_writebatch_put(wb, "bar", 3, "b", 1);
-    leveldb_writebatch_put(wb, "box", 3, "c", 1);
-    leveldb_writebatch_delete(wb, "bar", 3);
-    leveldb_write(db, woptions, wb, &err);
+    rocksdb_writebatch_t* wb = rocksdb_writebatch_create();
+    rocksdb_writebatch_put(wb, "foo", 3, "a", 1);
+    rocksdb_writebatch_clear(wb);
+    rocksdb_writebatch_put(wb, "bar", 3, "b", 1);
+    rocksdb_writebatch_put(wb, "box", 3, "c", 1);
+    rocksdb_writebatch_delete(wb, "bar", 3);
+    rocksdb_write(db, woptions, wb, &err);
     CheckNoError(err);
     CheckGet(db, roptions, "foo", "hello");
     CheckGet(db, roptions, "bar", NULL);
     CheckGet(db, roptions, "box", "c");
     int pos = 0;
-    leveldb_writebatch_iterate(wb, &pos, CheckPut, CheckDel);
+    rocksdb_writebatch_iterate(wb, &pos, CheckPut, CheckDel);
     CheckCondition(pos == 3);
-    leveldb_writebatch_destroy(wb);
+    rocksdb_writebatch_destroy(wb);
+  }
+
+  StartPhase("writebatch_rep");
+  {
+    rocksdb_writebatch_t* wb1 = rocksdb_writebatch_create();
+    rocksdb_writebatch_put(wb1, "baz", 3, "d", 1);
+    rocksdb_writebatch_put(wb1, "quux", 4, "e", 1);
+    rocksdb_writebatch_delete(wb1, "quux", 4);
+    size_t repsize1 = 0;
+    const char* rep = rocksdb_writebatch_data(wb1, &repsize1);
+    rocksdb_writebatch_t* wb2 = rocksdb_writebatch_create_from(rep, repsize1);
+    CheckCondition(rocksdb_writebatch_count(wb1) ==
+                   rocksdb_writebatch_count(wb2));
+    size_t repsize2 = 0;
+    CheckCondition(
+        memcmp(rep, rocksdb_writebatch_data(wb2, &repsize2), repsize1) == 0);
+    rocksdb_writebatch_destroy(wb1);
+    rocksdb_writebatch_destroy(wb2);
   }
 
   StartPhase("iter");
   {
-    leveldb_iterator_t* iter = leveldb_create_iterator(db, roptions);
-    CheckCondition(!leveldb_iter_valid(iter));
-    leveldb_iter_seek_to_first(iter);
-    CheckCondition(leveldb_iter_valid(iter));
+    rocksdb_iterator_t* iter = rocksdb_create_iterator(db, roptions);
+    CheckCondition(!rocksdb_iter_valid(iter));
+    rocksdb_iter_seek_to_first(iter);
+    CheckCondition(rocksdb_iter_valid(iter));
     CheckIter(iter, "box", "c");
-    leveldb_iter_next(iter);
+    rocksdb_iter_next(iter);
     CheckIter(iter, "foo", "hello");
-    leveldb_iter_prev(iter);
+    rocksdb_iter_prev(iter);
     CheckIter(iter, "box", "c");
-    leveldb_iter_prev(iter);
-    CheckCondition(!leveldb_iter_valid(iter));
-    leveldb_iter_seek_to_last(iter);
+    rocksdb_iter_prev(iter);
+    CheckCondition(!rocksdb_iter_valid(iter));
+    rocksdb_iter_seek_to_last(iter);
     CheckIter(iter, "foo", "hello");
-    leveldb_iter_seek(iter, "b", 1);
+    rocksdb_iter_seek(iter, "b", 1);
     CheckIter(iter, "box", "c");
-    leveldb_iter_get_error(iter, &err);
+    rocksdb_iter_get_error(iter, &err);
     CheckNoError(err);
-    leveldb_iter_destroy(iter);
+    rocksdb_iter_destroy(iter);
   }
 
   StartPhase("approximate_sizes");
@@ -279,39 +399,39 @@ int main(int argc, char** argv) {
     size_t start_len[2] = { 1, 21 };
     const char* limit[2] = { "k00000000000000010000", "z" };
     size_t limit_len[2] = { 21, 1 };
-    leveldb_writeoptions_set_sync(woptions, 0);
+    rocksdb_writeoptions_set_sync(woptions, 0);
     for (i = 0; i < n; i++) {
       snprintf(keybuf, sizeof(keybuf), "k%020d", i);
       snprintf(valbuf, sizeof(valbuf), "v%020d", i);
-      leveldb_put(db, woptions, keybuf, strlen(keybuf), valbuf, strlen(valbuf),
+      rocksdb_put(db, woptions, keybuf, strlen(keybuf), valbuf, strlen(valbuf),
                   &err);
       CheckNoError(err);
     }
-    leveldb_approximate_sizes(db, 2, start, start_len, limit, limit_len, sizes);
+    rocksdb_approximate_sizes(db, 2, start, start_len, limit, limit_len, sizes);
     CheckCondition(sizes[0] > 0);
     CheckCondition(sizes[1] > 0);
   }
 
   StartPhase("property");
   {
-    char* prop = leveldb_property_value(db, "nosuchprop");
+    char* prop = rocksdb_property_value(db, "nosuchprop");
     CheckCondition(prop == NULL);
-    prop = leveldb_property_value(db, "leveldb.stats");
+    prop = rocksdb_property_value(db, "rocksdb.stats");
     CheckCondition(prop != NULL);
     Free(&prop);
   }
 
   StartPhase("snapshot");
   {
-    const leveldb_snapshot_t* snap;
-    snap = leveldb_create_snapshot(db);
-    leveldb_delete(db, woptions, "foo", 3, &err);
+    const rocksdb_snapshot_t* snap;
+    snap = rocksdb_create_snapshot(db);
+    rocksdb_delete(db, woptions, "foo", 3, &err);
     CheckNoError(err);
-    leveldb_readoptions_set_snapshot(roptions, snap);
+    rocksdb_readoptions_set_snapshot(roptions, snap);
     CheckGet(db, roptions, "foo", "hello");
-    leveldb_readoptions_set_snapshot(roptions, NULL);
+    rocksdb_readoptions_set_snapshot(roptions, NULL);
     CheckGet(db, roptions, "foo", NULL);
-    leveldb_release_snapshot(db, snap);
+    rocksdb_release_snapshot(db, snap);
   }
 
   StartPhase("repair");
@@ -320,44 +440,44 @@ int main(int argc, char** argv) {
     // files (https://reviews.facebook.net/D6123) would leave
     // around deleted files and the repair process will find
     // those files and put them back into the database.
-    leveldb_compact_range(db, NULL, 0, NULL, 0);
-    leveldb_close(db);
-    leveldb_options_set_create_if_missing(options, 0);
-    leveldb_options_set_error_if_exists(options, 0);
-    leveldb_repair_db(options, dbname, &err);
+    rocksdb_compact_range(db, NULL, 0, NULL, 0);
+    rocksdb_close(db);
+    rocksdb_options_set_create_if_missing(options, 0);
+    rocksdb_options_set_error_if_exists(options, 0);
+    rocksdb_repair_db(options, dbname, &err);
     CheckNoError(err);
-    db = leveldb_open(options, dbname, &err);
+    db = rocksdb_open(options, dbname, &err);
     CheckNoError(err);
     CheckGet(db, roptions, "foo", NULL);
     CheckGet(db, roptions, "bar", NULL);
     CheckGet(db, roptions, "box", "c");
-    leveldb_options_set_create_if_missing(options, 1);
-    leveldb_options_set_error_if_exists(options, 1);
+    rocksdb_options_set_create_if_missing(options, 1);
+    rocksdb_options_set_error_if_exists(options, 1);
   }
 
   StartPhase("filter");
   for (run = 0; run < 2; run++) {
     // First run uses custom filter, second run uses bloom filter
     CheckNoError(err);
-    leveldb_filterpolicy_t* policy;
+    rocksdb_filterpolicy_t* policy;
     if (run == 0) {
-      policy = leveldb_filterpolicy_create(
-          NULL, FilterDestroy, FilterCreate, FilterKeyMatch, FilterName);
+      policy = rocksdb_filterpolicy_create(
+          NULL, FilterDestroy, FilterCreate, FilterKeyMatch, NULL, FilterName);
     } else {
-      policy = leveldb_filterpolicy_create_bloom(10);
+      policy = rocksdb_filterpolicy_create_bloom(10);
     }
 
     // Create new database
-    leveldb_close(db);
-    leveldb_destroy_db(options, dbname, &err);
-    leveldb_options_set_filter_policy(options, policy);
-    db = leveldb_open(options, dbname, &err);
+    rocksdb_close(db);
+    rocksdb_destroy_db(options, dbname, &err);
+    rocksdb_options_set_filter_policy(options, policy);
+    db = rocksdb_open(options, dbname, &err);
     CheckNoError(err);
-    leveldb_put(db, woptions, "foo", 3, "foovalue", 8, &err);
+    rocksdb_put(db, woptions, "foo", 3, "foovalue", 8, &err);
     CheckNoError(err);
-    leveldb_put(db, woptions, "bar", 3, "barvalue", 8, &err);
+    rocksdb_put(db, woptions, "bar", 3, "barvalue", 8, &err);
     CheckNoError(err);
-    leveldb_compact_range(db, NULL, 0, NULL, 0);
+    rocksdb_compact_range(db, NULL, 0, NULL, 0);
 
     fake_filter_result = 1;
     CheckGet(db, roptions, "foo", "foovalue");
@@ -372,18 +492,204 @@ int main(int argc, char** argv) {
       CheckGet(db, roptions, "foo", "foovalue");
       CheckGet(db, roptions, "bar", "barvalue");
     }
-    leveldb_options_set_filter_policy(options, NULL);
-    leveldb_filterpolicy_destroy(policy);
+    rocksdb_options_set_filter_policy(options, NULL);
+    rocksdb_filterpolicy_destroy(policy);
   }
 
+  StartPhase("compaction_filter");
+  {
+    rocksdb_options_t* options = rocksdb_options_create();
+    rocksdb_options_set_create_if_missing(options, 1);
+    rocksdb_compactionfilter_t* cfilter;
+    cfilter = rocksdb_compactionfilter_create(NULL, CFilterDestroy,
+                                              CFilterFilter, CFilterName);
+    // Create new database
+    rocksdb_close(db);
+    rocksdb_destroy_db(options, dbname, &err);
+    rocksdb_options_set_compaction_filter(options, cfilter);
+    db = CheckCompaction(db, options, roptions, woptions);
+
+    rocksdb_options_set_compaction_filter(options, NULL);
+    rocksdb_compactionfilter_destroy(cfilter);
+    rocksdb_options_destroy(options);
+  }
+
+  StartPhase("compaction_filter_factory");
+  {
+    rocksdb_options_t* options = rocksdb_options_create();
+    rocksdb_options_set_create_if_missing(options, 1);
+    rocksdb_compactionfilterfactory_t* factory;
+    factory = rocksdb_compactionfilterfactory_create(
+        NULL, CFilterFactoryDestroy, CFilterCreate, CFilterFactoryName);
+    // Create new database
+    rocksdb_close(db);
+    rocksdb_destroy_db(options, dbname, &err);
+    rocksdb_options_set_compaction_filter_factory(options, factory);
+    db = CheckCompaction(db, options, roptions, woptions);
+
+    rocksdb_options_set_compaction_filter_factory(options, NULL);
+    rocksdb_options_destroy(options);
+  }
+
+  StartPhase("merge_operator");
+  {
+    rocksdb_mergeoperator_t* merge_operator;
+    merge_operator = rocksdb_mergeoperator_create(
+        NULL, MergeOperatorDestroy, MergeOperatorFullMerge,
+        MergeOperatorPartialMerge, NULL, MergeOperatorName);
+    // Create new database
+    rocksdb_close(db);
+    rocksdb_destroy_db(options, dbname, &err);
+    rocksdb_options_set_merge_operator(options, merge_operator);
+    db = rocksdb_open(options, dbname, &err);
+    CheckNoError(err);
+    rocksdb_put(db, woptions, "foo", 3, "foovalue", 8, &err);
+    CheckNoError(err);
+    CheckGet(db, roptions, "foo", "foovalue");
+    rocksdb_merge(db, woptions, "foo", 3, "barvalue", 8, &err);
+    CheckNoError(err);
+    CheckGet(db, roptions, "foo", "fake");
+
+    // Merge of a non-existing value
+    rocksdb_merge(db, woptions, "bar", 3, "barvalue", 8, &err);
+    CheckNoError(err);
+    CheckGet(db, roptions, "bar", "fake");
+
+  }
+
+  StartPhase("columnfamilies");
+  {
+    rocksdb_close(db);
+    rocksdb_destroy_db(options, dbname, &err);
+    CheckNoError(err)
+
+    rocksdb_options_t* db_options = rocksdb_options_create();
+    rocksdb_options_set_create_if_missing(db_options, 1);
+    db = rocksdb_open(db_options, dbname, &err);
+    CheckNoError(err)
+    rocksdb_column_family_handle_t* cfh;
+    cfh = rocksdb_create_column_family(db, db_options, "cf1", &err);
+    rocksdb_column_family_handle_destroy(cfh);
+    CheckNoError(err);
+    rocksdb_close(db);
+
+    size_t cflen;
+    char** column_fams = rocksdb_list_column_families(db_options, dbname, &cflen, &err);
+    CheckNoError(err);
+    CheckEqual("default", column_fams[0], 7);
+    CheckEqual("cf1", column_fams[1], 3);
+    CheckCondition(cflen == 2);
+    rocksdb_list_column_families_destroy(column_fams, cflen);
+
+    rocksdb_options_t* cf_options = rocksdb_options_create();
+
+    const char* cf_names[2] = {"default", "cf1"};
+    const rocksdb_options_t* cf_opts[2] = {cf_options, cf_options};
+    rocksdb_column_family_handle_t* handles[2];
+    db = rocksdb_open_column_families(db_options, dbname, 2, cf_names, cf_opts, handles, &err);
+    CheckNoError(err);
+
+    rocksdb_put_cf(db, woptions, handles[1], "foo", 3, "hello", 5, &err);
+    CheckNoError(err);
+
+    CheckGetCF(db, roptions, handles[1], "foo", "hello");
+
+    rocksdb_delete_cf(db, woptions, handles[1], "foo", 3, &err);
+    CheckNoError(err);
+
+    CheckGetCF(db, roptions, handles[1], "foo", NULL);
+
+    rocksdb_writebatch_t* wb = rocksdb_writebatch_create();
+    rocksdb_writebatch_put_cf(wb, handles[1], "baz", 3, "a", 1);
+    rocksdb_writebatch_clear(wb);
+    rocksdb_writebatch_put_cf(wb, handles[1], "bar", 3, "b", 1);
+    rocksdb_writebatch_put_cf(wb, handles[1], "box", 3, "c", 1);
+    rocksdb_writebatch_delete_cf(wb, handles[1], "bar", 3);
+    rocksdb_write(db, woptions, wb, &err);
+    CheckNoError(err);
+    CheckGetCF(db, roptions, handles[1], "baz", NULL);
+    CheckGetCF(db, roptions, handles[1], "bar", NULL);
+    CheckGetCF(db, roptions, handles[1], "box", "c");
+    rocksdb_writebatch_destroy(wb);
+
+    rocksdb_iterator_t* iter = rocksdb_create_iterator_cf(db, roptions, handles[1]);
+    CheckCondition(!rocksdb_iter_valid(iter));
+    rocksdb_iter_seek_to_first(iter);
+    CheckCondition(rocksdb_iter_valid(iter));
+
+    int i;
+    for (i = 0; rocksdb_iter_valid(iter) != 0; rocksdb_iter_next(iter)) {
+      i++;
+    }
+    CheckCondition(i == 1);
+    rocksdb_iter_get_error(iter, &err);
+    CheckNoError(err);
+    rocksdb_iter_destroy(iter);
+
+    rocksdb_drop_column_family(db, handles[1], &err);
+    CheckNoError(err);
+    for (i = 0; i < 2; i++) {
+      rocksdb_column_family_handle_destroy(handles[i]);
+    }
+    rocksdb_close(db);
+    rocksdb_destroy_db(options, dbname, &err);
+    rocksdb_options_destroy(db_options);
+    rocksdb_options_destroy(cf_options);
+  }
+
+  StartPhase("prefix");
+  {
+    // Create new database
+    rocksdb_filterpolicy_t* policy = rocksdb_filterpolicy_create_bloom(10);
+    rocksdb_options_set_filter_policy(options, policy);
+    rocksdb_options_set_prefix_extractor(options, rocksdb_slicetransform_create_fixed_prefix(3));
+    rocksdb_options_set_hash_skip_list_rep(options, 5000, 4, 4);
+    rocksdb_options_set_plain_table_factory(options, 4, 10, 0.75, 16);
+
+    db = rocksdb_open(options, dbname, &err);
+    CheckNoError(err);
+
+    rocksdb_put(db, woptions, "foo1", 4, "foo", 3, &err);
+    CheckNoError(err);
+    rocksdb_put(db, woptions, "foo2", 4, "foo", 3, &err);
+    CheckNoError(err);
+    rocksdb_put(db, woptions, "foo3", 4, "foo", 3, &err);
+    CheckNoError(err);
+    rocksdb_put(db, woptions, "bar1", 4, "bar", 3, &err);
+    CheckNoError(err);
+    rocksdb_put(db, woptions, "bar2", 4, "bar", 3, &err);
+    CheckNoError(err);
+    rocksdb_put(db, woptions, "bar3", 4, "bar", 3, &err);
+    CheckNoError(err);
+
+    rocksdb_iterator_t* iter = rocksdb_create_iterator(db, roptions);
+    CheckCondition(!rocksdb_iter_valid(iter));
+
+    rocksdb_iter_seek(iter, "bar", 3);
+    rocksdb_iter_get_error(iter, &err);
+    CheckNoError(err);
+    CheckCondition(rocksdb_iter_valid(iter));
+
+    CheckIter(iter, "bar1", "bar");
+    rocksdb_iter_next(iter);
+    CheckIter(iter, "bar2", "bar");
+    rocksdb_iter_next(iter);
+    CheckIter(iter, "bar3", "bar");
+    rocksdb_iter_get_error(iter, &err);
+    CheckNoError(err);
+    rocksdb_iter_destroy(iter);
+    rocksdb_filterpolicy_destroy(policy);
+  }
+
+
   StartPhase("cleanup");
-  leveldb_close(db);
-  leveldb_options_destroy(options);
-  leveldb_readoptions_destroy(roptions);
-  leveldb_writeoptions_destroy(woptions);
-  leveldb_cache_destroy(cache);
-  leveldb_comparator_destroy(cmp);
-  leveldb_env_destroy(env);
+  rocksdb_close(db);
+  rocksdb_options_destroy(options);
+  rocksdb_readoptions_destroy(roptions);
+  rocksdb_writeoptions_destroy(woptions);
+  rocksdb_cache_destroy(cache);
+  rocksdb_comparator_destroy(cmp);
+  rocksdb_env_destroy(env);
 
   fprintf(stderr, "PASS\n");
   return 0;

db/column_family.cc

@@ -0,0 +1,642 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "db/column_family.h"
+
+#include <vector>
+#include <string>
+#include <algorithm>
+#include <limits>
+
+#include "db/db_impl.h"
+#include "db/version_set.h"
+#include "db/internal_stats.h"
+#include "db/compaction_picker.h"
+#include "db/table_properties_collector.h"
+#include "util/autovector.h"
+#include "util/hash_skiplist_rep.h"
+
+namespace rocksdb {
+
+ColumnFamilyHandleImpl::ColumnFamilyHandleImpl(ColumnFamilyData* cfd,
+                                               DBImpl* db, port::Mutex* mutex)
+    : cfd_(cfd), db_(db), mutex_(mutex) {
+  if (cfd_ != nullptr) {
+    cfd_->Ref();
+  }
+}
+
+ColumnFamilyHandleImpl::~ColumnFamilyHandleImpl() {
+  if (cfd_ != nullptr) {
+    DBImpl::DeletionState deletion_state;
+    mutex_->Lock();
+    if (cfd_->Unref()) {
+      delete cfd_;
+    }
+    db_->FindObsoleteFiles(deletion_state, false, true);
+    mutex_->Unlock();
+    if (deletion_state.HaveSomethingToDelete()) {
+      db_->PurgeObsoleteFiles(deletion_state);
+    }
+  }
+}
+
+uint32_t ColumnFamilyHandleImpl::GetID() const { return cfd()->GetID(); }
+
+namespace {
+// Fix user-supplied options to be reasonable
+template <class T, class V>
+static void ClipToRange(T* ptr, V minvalue, V maxvalue) {
+  if (static_cast<V>(*ptr) > maxvalue) *ptr = maxvalue;
+  if (static_cast<V>(*ptr) < minvalue) *ptr = minvalue;
+}
+}  // anonymous namespace
+
+ColumnFamilyOptions SanitizeOptions(const InternalKeyComparator* icmp,
+                                    const InternalFilterPolicy* ipolicy,
+                                    const ColumnFamilyOptions& src) {
+  ColumnFamilyOptions result = src;
+  result.comparator = icmp;
+  result.filter_policy = (src.filter_policy != nullptr) ? ipolicy : nullptr;
+#ifdef OS_MACOSX
+  // TODO(icanadi) make write_buffer_size uint64_t instead of size_t
+  ClipToRange(&result.write_buffer_size, ((size_t)64) << 10, ((size_t)1) << 30);
+#else
+  ClipToRange(&result.write_buffer_size,
+              ((size_t)64) << 10, ((size_t)64) << 30);
+#endif
+  // if user sets arena_block_size, we trust user to use this value. Otherwise,
+  // calculate a proper value from writer_buffer_size;
+  if (result.arena_block_size <= 0) {
+    result.arena_block_size = result.write_buffer_size / 10;
+  }
+  result.min_write_buffer_number_to_merge =
+      std::min(result.min_write_buffer_number_to_merge,
+               result.max_write_buffer_number - 1);
+  if (result.block_cache == nullptr && !result.no_block_cache) {
+    result.block_cache = NewLRUCache(8 << 20);
+  }
+  result.compression_per_level = src.compression_per_level;
+  if (result.block_size_deviation < 0 || result.block_size_deviation > 100) {
+    result.block_size_deviation = 0;
+  }
+  if (result.max_mem_compaction_level >= result.num_levels) {
+    result.max_mem_compaction_level = result.num_levels - 1;
+  }
+  if (result.soft_rate_limit > result.hard_rate_limit) {
+    result.soft_rate_limit = result.hard_rate_limit;
+  }
+  if (result.max_write_buffer_number < 2) {
+    result.max_write_buffer_number = 2;
+  }
+  if (!result.prefix_extractor) {
+    assert(result.memtable_factory);
+    Slice name = result.memtable_factory->Name();
+    if (name.compare("HashSkipListRepFactory") == 0 ||
+        name.compare("HashLinkListRepFactory") == 0) {
+      result.memtable_factory = std::make_shared<SkipListFactory>();
+    }
+  }
+
+  // -- Sanitize the table properties collector
+  // All user defined properties collectors will be wrapped by
+  // UserKeyTablePropertiesCollector since for them they only have the
+  // knowledge of the user keys; internal keys are invisible to them.
+  auto& collector_factories = result.table_properties_collector_factories;
+  for (size_t i = 0; i < result.table_properties_collector_factories.size();
+       ++i) {
+    assert(collector_factories[i]);
+    collector_factories[i] =
+        std::make_shared<UserKeyTablePropertiesCollectorFactory>(
+            collector_factories[i]);
+  }
+  // Add collector to collect internal key statistics
+  collector_factories.push_back(
+      std::make_shared<InternalKeyPropertiesCollectorFactory>());
+
+  if (result.compaction_style == kCompactionStyleFIFO) {
+    result.num_levels = 1;
+    // since we delete level0 files in FIFO compaction when there are too many
+    // of them, these options don't really mean anything
+    result.level0_file_num_compaction_trigger = std::numeric_limits<int>::max();
+    result.level0_slowdown_writes_trigger = std::numeric_limits<int>::max();
+    result.level0_stop_writes_trigger = std::numeric_limits<int>::max();
+  }
+
+  return result;
+}
+
+int SuperVersion::dummy = 0;
+void* const SuperVersion::kSVInUse = &SuperVersion::dummy;
+void* const SuperVersion::kSVObsolete = nullptr;
+
+SuperVersion::~SuperVersion() {
+  for (auto td : to_delete) {
+    delete td;
+  }
+}
+
+SuperVersion* SuperVersion::Ref() {
+  refs.fetch_add(1, std::memory_order_relaxed);
+  return this;
+}
+
+bool SuperVersion::Unref() {
+  // fetch_sub returns the previous value of ref
+  uint32_t previous_refs = refs.fetch_sub(1, std::memory_order_relaxed);
+  assert(previous_refs > 0);
+  return previous_refs == 1;
+}
+
+void SuperVersion::Cleanup() {
+  assert(refs.load(std::memory_order_relaxed) == 0);
+  imm->Unref(&to_delete);
+  MemTable* m = mem->Unref();
+  if (m != nullptr) {
+    to_delete.push_back(m);
+  }
+  current->Unref();
+}
+
+void SuperVersion::Init(MemTable* new_mem, MemTableListVersion* new_imm,
+                        Version* new_current) {
+  mem = new_mem;
+  imm = new_imm;
+  current = new_current;
+  mem->Ref();
+  imm->Ref();
+  current->Ref();
+  refs.store(1, std::memory_order_relaxed);
+}
+
+namespace {
+void SuperVersionUnrefHandle(void* ptr) {
+  // UnrefHandle is called when a thread exists or a ThreadLocalPtr gets
+  // destroyed. When former happens, the thread shouldn't see kSVInUse.
+  // When latter happens, we are in ~ColumnFamilyData(), no get should happen as
+  // well.
+  SuperVersion* sv = static_cast<SuperVersion*>(ptr);
+  if (sv->Unref()) {
+    sv->db_mutex->Lock();
+    sv->Cleanup();
+    sv->db_mutex->Unlock();
+    delete sv;
+  }
+}
+}  // anonymous namespace
+
+ColumnFamilyData::ColumnFamilyData(const std::string& dbname, uint32_t id,
+                                   const std::string& name,
+                                   Version* dummy_versions, Cache* table_cache,
+                                   const ColumnFamilyOptions& options,
+                                   const DBOptions* db_options,
+                                   const EnvOptions& storage_options,
+                                   ColumnFamilySet* column_family_set)
+    : id_(id),
+      name_(name),
+      dummy_versions_(dummy_versions),
+      current_(nullptr),
+      refs_(0),
+      dropped_(false),
+      internal_comparator_(options.comparator),
+      internal_filter_policy_(options.filter_policy),
+      options_(*db_options, SanitizeOptions(&internal_comparator_,
+                                            &internal_filter_policy_, options)),
+      mem_(nullptr),
+      imm_(options_.min_write_buffer_number_to_merge),
+      super_version_(nullptr),
+      super_version_number_(0),
+      local_sv_(new ThreadLocalPtr(&SuperVersionUnrefHandle)),
+      next_(nullptr),
+      prev_(nullptr),
+      log_number_(0),
+      need_slowdown_for_num_level0_files_(false),
+      column_family_set_(column_family_set) {
+  Ref();
+
+  // if dummy_versions is nullptr, then this is a dummy column family.
+  if (dummy_versions != nullptr) {
+    internal_stats_.reset(new InternalStats(
+        options_.num_levels, db_options->env, db_options->statistics.get()));
+    table_cache_.reset(new TableCache(&options_, storage_options, table_cache));
+    if (options_.compaction_style == kCompactionStyleUniversal) {
+      compaction_picker_.reset(
+          new UniversalCompactionPicker(&options_, &internal_comparator_));
+    } else if (options_.compaction_style == kCompactionStyleLevel) {
+      compaction_picker_.reset(
+          new LevelCompactionPicker(&options_, &internal_comparator_));
+    } else {
+      assert(options_.compaction_style == kCompactionStyleFIFO);
+      compaction_picker_.reset(
+          new FIFOCompactionPicker(&options_, &internal_comparator_));
+    }
+
+    Log(options_.info_log, "Options for column family \"%s\":\n",
+        name.c_str());
+    const ColumnFamilyOptions* cf_options = &options_;
+    cf_options->Dump(options_.info_log.get());
+  }
+
+  RecalculateWriteStallConditions();
+}
+
+// DB mutex held
+ColumnFamilyData::~ColumnFamilyData() {
+  assert(refs_ == 0);
+  // remove from linked list
+  auto prev = prev_;
+  auto next = next_;
+  prev->next_ = next;
+  next->prev_ = prev;
+
+  // it's nullptr for dummy CFD
+  if (column_family_set_ != nullptr) {
+    // remove from column_family_set
+    column_family_set_->RemoveColumnFamily(this);
+  }
+
+  if (current_ != nullptr) {
+    current_->Unref();
+  }
+
+  if (super_version_ != nullptr) {
+    // Release SuperVersion reference kept in ThreadLocalPtr.
+    // This must be done outside of mutex_ since unref handler can lock mutex.
+    super_version_->db_mutex->Unlock();
+    local_sv_.reset();
+    super_version_->db_mutex->Lock();
+
+    bool is_last_reference __attribute__((unused));
+    is_last_reference = super_version_->Unref();
+    assert(is_last_reference);
+    super_version_->Cleanup();
+    delete super_version_;
+    super_version_ = nullptr;
+  }
+
+  if (dummy_versions_ != nullptr) {
+    // List must be empty
+    assert(dummy_versions_->next_ == dummy_versions_);
+    delete dummy_versions_;
+  }
+
+  if (mem_ != nullptr) {
+    delete mem_->Unref();
+  }
+  autovector<MemTable*> to_delete;
+  imm_.current()->Unref(&to_delete);
+  for (MemTable* m : to_delete) {
+    delete m;
+  }
+}
+
+void ColumnFamilyData::RecalculateWriteStallConditions() {
+  need_wait_for_num_memtables_ =
+    (imm()->size() == options()->max_write_buffer_number - 1);
+
+  if (current_ != nullptr) {
+    need_wait_for_num_level0_files_ =
+      (current_->NumLevelFiles(0) >= options()->level0_stop_writes_trigger);
+  } else {
+    need_wait_for_num_level0_files_ = false;
+  }
+
+  RecalculateWriteStallRateLimitsConditions();
+}
+
+void ColumnFamilyData::RecalculateWriteStallRateLimitsConditions() {
+  if (current_ != nullptr) {
+    exceeds_hard_rate_limit_ =
+        (options()->hard_rate_limit > 1.0 &&
+         current_->MaxCompactionScore() > options()->hard_rate_limit);
+
+    exceeds_soft_rate_limit_ =
+        (options()->soft_rate_limit > 0.0 &&
+         current_->MaxCompactionScore() > options()->soft_rate_limit);
+  } else {
+    exceeds_hard_rate_limit_ = false;
+    exceeds_soft_rate_limit_ = false;
+  }
+}
+
+const EnvOptions* ColumnFamilyData::soptions() const {
+  return &(column_family_set_->storage_options_);
+}
+
+void ColumnFamilyData::SetCurrent(Version* current) {
+  current_ = current;
+  need_slowdown_for_num_level0_files_ =
+      (options_.level0_slowdown_writes_trigger >= 0 &&
+       current_->NumLevelFiles(0) >= options_.level0_slowdown_writes_trigger);
+}
+
+void ColumnFamilyData::CreateNewMemtable() {
+  assert(current_ != nullptr);
+  if (mem_ != nullptr) {
+    delete mem_->Unref();
+  }
+  mem_ = new MemTable(internal_comparator_, options_);
+  mem_->Ref();
+}
+
+Compaction* ColumnFamilyData::PickCompaction(LogBuffer* log_buffer) {
+  auto result = compaction_picker_->PickCompaction(current_, log_buffer);
+  RecalculateWriteStallRateLimitsConditions();
+  return result;
+}
+
+Compaction* ColumnFamilyData::CompactRange(int input_level, int output_level,
+                                           const InternalKey* begin,
+                                           const InternalKey* end,
+                                           InternalKey** compaction_end) {
+  return compaction_picker_->CompactRange(current_, input_level, output_level,
+                                          begin, end, compaction_end);
+}
+
+SuperVersion* ColumnFamilyData::GetReferencedSuperVersion(
+    port::Mutex* db_mutex) {
+  SuperVersion* sv = nullptr;
+  if (LIKELY(column_family_set_->db_options_->allow_thread_local)) {
+    sv = GetThreadLocalSuperVersion(db_mutex);
+    sv->Ref();
+    if (!ReturnThreadLocalSuperVersion(sv)) {
+      sv->Unref();
+    }
+  } else {
+    db_mutex->Lock();
+    sv = super_version_->Ref();
+    db_mutex->Unlock();
+  }
+  return sv;
+}
+
+SuperVersion* ColumnFamilyData::GetThreadLocalSuperVersion(
+    port::Mutex* db_mutex) {
+  SuperVersion* sv = nullptr;
+  // The SuperVersion is cached in thread local storage to avoid acquiring
+  // mutex when SuperVersion does not change since the last use. When a new
+  // SuperVersion is installed, the compaction or flush thread cleans up
+  // cached SuperVersion in all existing thread local storage. To avoid
+  // acquiring mutex for this operation, we use atomic Swap() on the thread
+  // local pointer to guarantee exclusive access. If the thread local pointer
+  // is being used while a new SuperVersion is installed, the cached
+  // SuperVersion can become stale. In that case, the background thread would
+  // have swapped in kSVObsolete. We re-check the value at when returning
+  // SuperVersion back to thread local, with an atomic compare and swap.
+  // The superversion will need to be released if detected to be stale.
+  void* ptr = local_sv_->Swap(SuperVersion::kSVInUse);
+  // Invariant:
+  // (1) Scrape (always) installs kSVObsolete in ThreadLocal storage
+  // (2) the Swap above (always) installs kSVInUse, ThreadLocal storage
+  // should only keep kSVInUse before ReturnThreadLocalSuperVersion call
+  // (if no Scrape happens).
+  assert(ptr != SuperVersion::kSVInUse);
+  sv = static_cast<SuperVersion*>(ptr);
+  if (sv == SuperVersion::kSVObsolete ||
+      sv->version_number != super_version_number_.load()) {
+    RecordTick(options_.statistics.get(), NUMBER_SUPERVERSION_ACQUIRES);
+    SuperVersion* sv_to_delete = nullptr;
+
+    if (sv && sv->Unref()) {
+      RecordTick(options_.statistics.get(), NUMBER_SUPERVERSION_CLEANUPS);
+      db_mutex->Lock();
+      // NOTE: underlying resources held by superversion (sst files) might
+      // not be released until the next background job.
+      sv->Cleanup();
+      sv_to_delete = sv;
+    } else {
+      db_mutex->Lock();
+    }
+    sv = super_version_->Ref();
+    db_mutex->Unlock();
+
+    delete sv_to_delete;
+  }
+  assert(sv != nullptr);
+  return sv;
+}
+
+bool ColumnFamilyData::ReturnThreadLocalSuperVersion(SuperVersion* sv) {
+  assert(sv != nullptr);
+  // Put the SuperVersion back
+  void* expected = SuperVersion::kSVInUse;
+  if (local_sv_->CompareAndSwap(static_cast<void*>(sv), expected)) {
+    // When we see kSVInUse in the ThreadLocal, we are sure ThreadLocal
+    // storage has not been altered and no Scrape has happend. The
+    // SuperVersion is still current.
+    return true;
+  } else {
+    // ThreadLocal scrape happened in the process of this GetImpl call (after
+    // thread local Swap() at the beginning and before CompareAndSwap()).
+    // This means the SuperVersion it holds is obsolete.
+    assert(expected == SuperVersion::kSVObsolete);
+  }
+  return false;
+}
+
+SuperVersion* ColumnFamilyData::InstallSuperVersion(
+    SuperVersion* new_superversion, port::Mutex* db_mutex) {
+  new_superversion->db_mutex = db_mutex;
+  new_superversion->Init(mem_, imm_.current(), current_);
+  SuperVersion* old_superversion = super_version_;
+  super_version_ = new_superversion;
+  ++super_version_number_;
+  super_version_->version_number = super_version_number_;
+  // Reset SuperVersions cached in thread local storage
+  if (column_family_set_->db_options_->allow_thread_local) {
+    ResetThreadLocalSuperVersions();
+  }
+
+  RecalculateWriteStallConditions();
+
+  if (old_superversion != nullptr && old_superversion->Unref()) {
+    old_superversion->Cleanup();
+    return old_superversion;  // will let caller delete outside of mutex
+  }
+  return nullptr;
+}
+
+void ColumnFamilyData::ResetThreadLocalSuperVersions() {
+  autovector<void*> sv_ptrs;
+  local_sv_->Scrape(&sv_ptrs, SuperVersion::kSVObsolete);
+  for (auto ptr : sv_ptrs) {
+    assert(ptr);
+    if (ptr == SuperVersion::kSVInUse) {
+      continue;
+    }
+    auto sv = static_cast<SuperVersion*>(ptr);
+    if (sv->Unref()) {
+      sv->Cleanup();
+      delete sv;
+    }
+  }
+}
+
+ColumnFamilySet::ColumnFamilySet(const std::string& dbname,
+                                 const DBOptions* db_options,
+                                 const EnvOptions& storage_options,
+                                 Cache* table_cache)
+    : max_column_family_(0),
+      dummy_cfd_(new ColumnFamilyData(dbname, 0, "", nullptr, nullptr,
+                                      ColumnFamilyOptions(), db_options,
+                                      storage_options_, nullptr)),
+      default_cfd_cache_(nullptr),
+      db_name_(dbname),
+      db_options_(db_options),
+      storage_options_(storage_options),
+      table_cache_(table_cache),
+      spin_lock_(ATOMIC_FLAG_INIT) {
+  // initialize linked list
+  dummy_cfd_->prev_ = dummy_cfd_;
+  dummy_cfd_->next_ = dummy_cfd_;
+}
+
+ColumnFamilySet::~ColumnFamilySet() {
+  while (column_family_data_.size() > 0) {
+    // cfd destructor will delete itself from column_family_data_
+    auto cfd = column_family_data_.begin()->second;
+    cfd->Unref();
+    delete cfd;
+  }
+  dummy_cfd_->Unref();
+  delete dummy_cfd_;
+}
+
+ColumnFamilyData* ColumnFamilySet::GetDefault() const {
+  assert(default_cfd_cache_ != nullptr);
+  return default_cfd_cache_;
+}
+
+ColumnFamilyData* ColumnFamilySet::GetColumnFamily(uint32_t id) const {
+  auto cfd_iter = column_family_data_.find(id);
+  if (cfd_iter != column_family_data_.end()) {
+    return cfd_iter->second;
+  } else {
+    return nullptr;
+  }
+}
+
+ColumnFamilyData* ColumnFamilySet::GetColumnFamily(const std::string& name)
+    const {
+  auto cfd_iter = column_families_.find(name);
+  if (cfd_iter != column_families_.end()) {
+    auto cfd = GetColumnFamily(cfd_iter->second);
+    assert(cfd != nullptr);
+    return cfd;
+  } else {
+    return nullptr;
+  }
+}
+
+uint32_t ColumnFamilySet::GetNextColumnFamilyID() {
+  return ++max_column_family_;
+}
+
+uint32_t ColumnFamilySet::GetMaxColumnFamily() { return max_column_family_; }
+
+void ColumnFamilySet::UpdateMaxColumnFamily(uint32_t new_max_column_family) {
+  max_column_family_ = std::max(new_max_column_family, max_column_family_);
+}
+
+size_t ColumnFamilySet::NumberOfColumnFamilies() const {
+  return column_families_.size();
+}
+
+// under a DB mutex
+ColumnFamilyData* ColumnFamilySet::CreateColumnFamily(
+    const std::string& name, uint32_t id, Version* dummy_versions,
+    const ColumnFamilyOptions& options) {
+  assert(column_families_.find(name) == column_families_.end());
+  ColumnFamilyData* new_cfd =
+      new ColumnFamilyData(db_name_, id, name, dummy_versions, table_cache_,
+                           options, db_options_, storage_options_, this);
+  Lock();
+  column_families_.insert({name, id});
+  column_family_data_.insert({id, new_cfd});
+  Unlock();
+  max_column_family_ = std::max(max_column_family_, id);
+  // add to linked list
+  new_cfd->next_ = dummy_cfd_;
+  auto prev = dummy_cfd_->prev_;
+  new_cfd->prev_ = prev;
+  prev->next_ = new_cfd;
+  dummy_cfd_->prev_ = new_cfd;
+  if (id == 0) {
+    default_cfd_cache_ = new_cfd;
+  }
+  return new_cfd;
+}
+
+void ColumnFamilySet::Lock() {
+  // spin lock
+  while (spin_lock_.test_and_set(std::memory_order_acquire)) {
+  }
+}
+
+void ColumnFamilySet::Unlock() { spin_lock_.clear(std::memory_order_release); }
+
+// REQUIRES: DB mutex held
+void ColumnFamilySet::FreeDeadColumnFamilies() {
+  autovector<ColumnFamilyData*> to_delete;
+  for (auto cfd = dummy_cfd_->next_; cfd != dummy_cfd_; cfd = cfd->next_) {
+    if (cfd->refs_ == 0) {
+      to_delete.push_back(cfd);
+    }
+  }
+  for (auto cfd : to_delete) {
+    // this is very rare, so it's not a problem that we do it under a mutex
+    delete cfd;
+  }
+}
+
+// under a DB mutex
+void ColumnFamilySet::RemoveColumnFamily(ColumnFamilyData* cfd) {
+  auto cfd_iter = column_family_data_.find(cfd->GetID());
+  assert(cfd_iter != column_family_data_.end());
+  Lock();
+  column_family_data_.erase(cfd_iter);
+  column_families_.erase(cfd->GetName());
+  Unlock();
+}
+
+bool ColumnFamilyMemTablesImpl::Seek(uint32_t column_family_id) {
+  if (column_family_id == 0) {
+    // optimization for common case
+    current_ = column_family_set_->GetDefault();
+  } else {
+    // maybe outside of db mutex, should lock
+    column_family_set_->Lock();
+    current_ = column_family_set_->GetColumnFamily(column_family_id);
+    column_family_set_->Unlock();
+  }
+  handle_.SetCFD(current_);
+  return current_ != nullptr;
+}
+
+uint64_t ColumnFamilyMemTablesImpl::GetLogNumber() const {
+  assert(current_ != nullptr);
+  return current_->GetLogNumber();
+}
+
+MemTable* ColumnFamilyMemTablesImpl::GetMemTable() const {
+  assert(current_ != nullptr);
+  return current_->mem();
+}
+
+const Options* ColumnFamilyMemTablesImpl::GetOptions() const {
+  assert(current_ != nullptr);
+  return current_->options();
+}
+
+ColumnFamilyHandle* ColumnFamilyMemTablesImpl::GetColumnFamilyHandle() {
+  assert(current_ != nullptr);
+  return &handle_;
+}
+
+}  // namespace rocksdb

db/column_family.h

@@ -0,0 +1,459 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#pragma once
+
+#include <unordered_map>
+#include <string>
+#include <vector>
+#include <atomic>
+
+#include "rocksdb/options.h"
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"
+#include "db/memtable_list.h"
+#include "db/write_batch_internal.h"
+#include "db/table_cache.h"
+#include "util/thread_local.h"
+
+namespace rocksdb {
+
+class Version;
+class VersionSet;
+class MemTable;
+class MemTableListVersion;
+class CompactionPicker;
+class Compaction;
+class InternalKey;
+class InternalStats;
+class ColumnFamilyData;
+class DBImpl;
+class LogBuffer;
+
+// ColumnFamilyHandleImpl is the class that clients use to access different
+// column families. It has non-trivial destructor, which gets called when client
+// is done using the column family
+class ColumnFamilyHandleImpl : public ColumnFamilyHandle {
+ public:
+  // create while holding the mutex
+  ColumnFamilyHandleImpl(ColumnFamilyData* cfd, DBImpl* db, port::Mutex* mutex);
+  // destroy without mutex
+  virtual ~ColumnFamilyHandleImpl();
+  virtual ColumnFamilyData* cfd() const { return cfd_; }
+
+  virtual uint32_t GetID() const;
+
+ private:
+  ColumnFamilyData* cfd_;
+  DBImpl* db_;
+  port::Mutex* mutex_;
+};
+
+// Does not ref-count ColumnFamilyData
+// We use this dummy ColumnFamilyHandleImpl because sometimes MemTableInserter
+// calls DBImpl methods. When this happens, MemTableInserter need access to
+// ColumnFamilyHandle (same as the client would need). In that case, we feed
+// MemTableInserter dummy ColumnFamilyHandle and enable it to call DBImpl
+// methods
+class ColumnFamilyHandleInternal : public ColumnFamilyHandleImpl {
+ public:
+  ColumnFamilyHandleInternal()
+      : ColumnFamilyHandleImpl(nullptr, nullptr, nullptr) {}
+
+  void SetCFD(ColumnFamilyData* cfd) { internal_cfd_ = cfd; }
+  virtual ColumnFamilyData* cfd() const override { return internal_cfd_; }
+
+ private:
+  ColumnFamilyData* internal_cfd_;
+};
+
+// holds references to memtable, all immutable memtables and version
+struct SuperVersion {
+  MemTable* mem;
+  MemTableListVersion* imm;
+  Version* current;
+  std::atomic<uint32_t> refs;
+  // We need to_delete because during Cleanup(), imm->Unref() returns
+  // all memtables that we need to free through this vector. We then
+  // delete all those memtables outside of mutex, during destruction
+  autovector<MemTable*> to_delete;
+  // Version number of the current SuperVersion
+  uint64_t version_number;
+  port::Mutex* db_mutex;
+
+  // should be called outside the mutex
+  SuperVersion() = default;
+  ~SuperVersion();
+  SuperVersion* Ref();
+
+  bool Unref();
+
+  // call these two methods with db mutex held
+  // Cleanup unrefs mem, imm and current. Also, it stores all memtables
+  // that needs to be deleted in to_delete vector. Unrefing those
+  // objects needs to be done in the mutex
+  void Cleanup();
+  void Init(MemTable* new_mem, MemTableListVersion* new_imm,
+            Version* new_current);
+
+  // The value of dummy is not actually used. kSVInUse takes its address as a
+  // mark in the thread local storage to indicate the SuperVersion is in use
+  // by thread. This way, the value of kSVInUse is guaranteed to have no
+  // conflict with SuperVersion object address and portable on different
+  // platform.
+  static int dummy;
+  static void* const kSVInUse;
+  static void* const kSVObsolete;
+};
+
+extern ColumnFamilyOptions SanitizeOptions(const InternalKeyComparator* icmp,
+                                           const InternalFilterPolicy* ipolicy,
+                                           const ColumnFamilyOptions& src);
+
+class ColumnFamilySet;
+
+// This class keeps all the data that a column family needs. It's mosly dumb and
+// used just to provide access to metadata.
+// Most methods require DB mutex held, unless otherwise noted
+class ColumnFamilyData {
+ public:
+  ~ColumnFamilyData();
+
+  // thread-safe
+  uint32_t GetID() const { return id_; }
+  // thread-safe
+  const std::string& GetName() const { return name_; }
+
+  void Ref() { ++refs_; }
+  // will just decrease reference count to 0, but will not delete it. returns
+  // true if the ref count was decreased to zero. in that case, it can be
+  // deleted by the caller immediatelly, or later, by calling
+  // FreeDeadColumnFamilies()
+  bool Unref() {
+    assert(refs_ > 0);
+    return --refs_ == 0;
+  }
+
+  // This can only be called from single-threaded VersionSet::LogAndApply()
+  // After dropping column family no other operation on that column family
+  // will be executed. All the files and memory will be, however, kept around
+  // until client drops the column family handle. That way, client can still
+  // access data from dropped column family.
+  // Column family can be dropped and still alive. In that state:
+  // *) Column family is not included in the iteration.
+  // *) Compaction and flush is not executed on the dropped column family.
+  // *) Client can continue writing and reading from column family. However, all
+  // writes stay in the current memtable.
+  // When the dropped column family is unreferenced, then we:
+  // *) delete all memory associated with that column family
+  // *) delete all the files associated with that column family
+  void SetDropped() {
+    // can't drop default CF
+    assert(id_ != 0);
+    dropped_ = true;
+  }
+  bool IsDropped() const { return dropped_; }
+
+  // thread-safe
+  int NumberLevels() const { return options_.num_levels; }
+
+  void SetLogNumber(uint64_t log_number) { log_number_ = log_number; }
+  uint64_t GetLogNumber() const { return log_number_; }
+
+  // thread-safe
+  const Options* options() const { return &options_; }
+  const EnvOptions* soptions() const;
+
+  InternalStats* internal_stats() { return internal_stats_.get(); }
+
+  MemTableList* imm() { return &imm_; }
+  MemTable* mem() { return mem_; }
+  Version* current() { return current_; }
+  Version* dummy_versions() { return dummy_versions_; }
+  void SetMemtable(MemTable* new_mem) { mem_ = new_mem; }
+  void SetCurrent(Version* current);
+  void CreateNewMemtable();
+
+  TableCache* table_cache() const { return table_cache_.get(); }
+
+  // See documentation in compaction_picker.h
+  Compaction* PickCompaction(LogBuffer* log_buffer);
+  Compaction* CompactRange(int input_level, int output_level,
+                           const InternalKey* begin, const InternalKey* end,
+                           InternalKey** compaction_end);
+
+  CompactionPicker* compaction_picker() { return compaction_picker_.get(); }
+  // thread-safe
+  const Comparator* user_comparator() const {
+    return internal_comparator_.user_comparator();
+  }
+  // thread-safe
+  const InternalKeyComparator& internal_comparator() const {
+    return internal_comparator_;
+  }
+
+  SuperVersion* GetSuperVersion() { return super_version_; }
+  // thread-safe
+  // Return a already referenced SuperVersion to be used safely.
+  SuperVersion* GetReferencedSuperVersion(port::Mutex* db_mutex);
+  // thread-safe
+  // Get SuperVersion stored in thread local storage. If it does not exist,
+  // get a reference from a current SuperVersion.
+  SuperVersion* GetThreadLocalSuperVersion(port::Mutex* db_mutex);
+  // Try to return SuperVersion back to thread local storage. Retrun true on
+  // success and false on failure. It fails when the thread local storage
+  // contains anything other than SuperVersion::kSVInUse flag.
+  bool ReturnThreadLocalSuperVersion(SuperVersion* sv);
+  // thread-safe
+  uint64_t GetSuperVersionNumber() const {
+    return super_version_number_.load();
+  }
+  // will return a pointer to SuperVersion* if previous SuperVersion
+  // if its reference count is zero and needs deletion or nullptr if not
+  // As argument takes a pointer to allocated SuperVersion to enable
+  // the clients to allocate SuperVersion outside of mutex.
+  SuperVersion* InstallSuperVersion(SuperVersion* new_superversion,
+                                    port::Mutex* db_mutex);
+
+  void ResetThreadLocalSuperVersions();
+
+  // A Flag indicating whether write needs to slowdown because of there are
+  // too many number of level0 files.
+  bool NeedSlowdownForNumLevel0Files() const {
+    return need_slowdown_for_num_level0_files_;
+  }
+
+  bool NeedWaitForNumLevel0Files() const {
+    return need_wait_for_num_level0_files_;
+  }
+
+  bool NeedWaitForNumMemtables() const {
+    return need_wait_for_num_memtables_;
+  }
+
+  bool ExceedsSoftRateLimit() const {
+    return exceeds_soft_rate_limit_;
+  }
+
+  bool ExceedsHardRateLimit() const {
+    return exceeds_hard_rate_limit_;
+  }
+
+ private:
+  friend class ColumnFamilySet;
+  ColumnFamilyData(const std::string& dbname, uint32_t id,
+                   const std::string& name, Version* dummy_versions,
+                   Cache* table_cache, const ColumnFamilyOptions& options,
+                   const DBOptions* db_options,
+                   const EnvOptions& storage_options,
+                   ColumnFamilySet* column_family_set);
+
+  // Recalculate some small conditions, which are changed only during
+  // compaction, adding new memtable and/or
+  // recalculation of compaction score. These values are used in
+  // DBImpl::MakeRoomForWrite function to decide, if it need to make
+  // a write stall
+  void RecalculateWriteStallConditions();
+  void RecalculateWriteStallRateLimitsConditions();
+
+  uint32_t id_;
+  const std::string name_;
+  Version* dummy_versions_;  // Head of circular doubly-linked list of versions.
+  Version* current_;         // == dummy_versions->prev_
+
+  int refs_;                   // outstanding references to ColumnFamilyData
+  bool dropped_;               // true if client dropped it
+
+  const InternalKeyComparator internal_comparator_;
+  const InternalFilterPolicy internal_filter_policy_;
+
+  Options const options_;
+
+  std::unique_ptr<TableCache> table_cache_;
+
+  std::unique_ptr<InternalStats> internal_stats_;
+
+  MemTable* mem_;
+  MemTableList imm_;
+  SuperVersion* super_version_;
+
+  // An ordinal representing the current SuperVersion. Updated by
+  // InstallSuperVersion(), i.e. incremented every time super_version_
+  // changes.
+  std::atomic<uint64_t> super_version_number_;
+
+  // Thread's local copy of SuperVersion pointer
+  // This needs to be destructed before mutex_
+  std::unique_ptr<ThreadLocalPtr> local_sv_;
+
+  // pointers for a circular linked list. we use it to support iterations
+  // that can be concurrent with writes
+  ColumnFamilyData* next_;
+  ColumnFamilyData* prev_;
+
+  // This is the earliest log file number that contains data from this
+  // Column Family. All earlier log files must be ignored and not
+  // recovered from
+  uint64_t log_number_;
+
+  // A flag indicating whether we should delay writes because
+  // we have too many level 0 files
+  bool need_slowdown_for_num_level0_files_;
+
+  // These 4 variables are updated only after compaction,
+  // adding new memtable, flushing memtables to files
+  // and/or add recalculation of compaction score.
+  // That's why theirs values are cached in ColumnFamilyData.
+  // Recalculation is made by RecalculateWriteStallConditions and
+  // RecalculateWriteStallRateLimitsConditions function. They are used
+  // in DBImpl::MakeRoomForWrite function to decide, if it need
+  // to sleep during write operation
+  bool need_wait_for_num_memtables_;
+
+  bool need_wait_for_num_level0_files_;
+
+  bool exceeds_hard_rate_limit_;
+
+  bool exceeds_soft_rate_limit_;
+
+  // An object that keeps all the compaction stats
+  // and picks the next compaction
+  std::unique_ptr<CompactionPicker> compaction_picker_;
+
+  ColumnFamilySet* column_family_set_;
+};
+
+// ColumnFamilySet has interesting thread-safety requirements
+// * CreateColumnFamily() or RemoveColumnFamily() -- need to protect by DB
+// mutex. Inside, column_family_data_ and column_families_ will be protected
+// by Lock() and Unlock(). CreateColumnFamily() should ONLY be called from
+// VersionSet::LogAndApply() in the normal runtime. It is also called
+// during Recovery and in DumpManifest(). RemoveColumnFamily() is called
+// from ColumnFamilyData destructor
+// * Iteration -- hold DB mutex, but you can release it in the body of
+// iteration. If you release DB mutex in body, reference the column
+// family before the mutex and unreference after you unlock, since the column
+// family might get dropped when the DB mutex is released
+// * GetDefault() -- thread safe
+// * GetColumnFamily() -- either inside of DB mutex or call Lock() <-> Unlock()
+// * GetNextColumnFamilyID(), GetMaxColumnFamily(), UpdateMaxColumnFamily(),
+// NumberOfColumnFamilies -- inside of DB mutex
+class ColumnFamilySet {
+ public:
+  // ColumnFamilySet supports iteration
+  class iterator {
+   public:
+    explicit iterator(ColumnFamilyData* cfd)
+        : current_(cfd) {}
+    iterator& operator++() {
+      // dummy is never dead or dropped, so this will never be infinite
+      do {
+        current_ = current_->next_;
+      } while (current_->refs_ == 0 || current_->IsDropped());
+      return *this;
+    }
+    bool operator!=(const iterator& other) {
+      return this->current_ != other.current_;
+    }
+    ColumnFamilyData* operator*() { return current_; }
+
+   private:
+    ColumnFamilyData* current_;
+  };
+
+  ColumnFamilySet(const std::string& dbname, const DBOptions* db_options,
+                  const EnvOptions& storage_options, Cache* table_cache);
+  ~ColumnFamilySet();
+
+  ColumnFamilyData* GetDefault() const;
+  // GetColumnFamily() calls return nullptr if column family is not found
+  ColumnFamilyData* GetColumnFamily(uint32_t id) const;
+  ColumnFamilyData* GetColumnFamily(const std::string& name) const;
+  // this call will return the next available column family ID. it guarantees
+  // that there is no column family with id greater than or equal to the
+  // returned value in the current running instance or anytime in RocksDB
+  // instance history.
+  uint32_t GetNextColumnFamilyID();
+  uint32_t GetMaxColumnFamily();
+  void UpdateMaxColumnFamily(uint32_t new_max_column_family);
+  size_t NumberOfColumnFamilies() const;
+
+  ColumnFamilyData* CreateColumnFamily(const std::string& name, uint32_t id,
+                                       Version* dummy_version,
+                                       const ColumnFamilyOptions& options);
+
+  iterator begin() { return iterator(dummy_cfd_->next_); }
+  iterator end() { return iterator(dummy_cfd_); }
+
+  void Lock();
+  void Unlock();
+
+  // REQUIRES: DB mutex held
+  // Don't call while iterating over ColumnFamilySet
+  void FreeDeadColumnFamilies();
+
+ private:
+  friend class ColumnFamilyData;
+  // helper function that gets called from cfd destructor
+  // REQUIRES: DB mutex held
+  void RemoveColumnFamily(ColumnFamilyData* cfd);
+
+  // column_families_ and column_family_data_ need to be protected:
+  // * when mutating: 1. DB mutex locked first, 2. spinlock locked second
+  // * when reading, either: 1. lock DB mutex, or 2. lock spinlock
+  //  (if both, respect the ordering to avoid deadlock!)
+  std::unordered_map<std::string, uint32_t> column_families_;
+  std::unordered_map<uint32_t, ColumnFamilyData*> column_family_data_;
+
+  uint32_t max_column_family_;
+  ColumnFamilyData* dummy_cfd_;
+  // We don't hold the refcount here, since default column family always exists
+  // We are also not responsible for cleaning up default_cfd_cache_. This is
+  // just a cache that makes common case (accessing default column family)
+  // faster
+  ColumnFamilyData* default_cfd_cache_;
+
+  const std::string db_name_;
+  const DBOptions* const db_options_;
+  const EnvOptions storage_options_;
+  Cache* table_cache_;
+  std::atomic_flag spin_lock_;
+};
+
+// We use ColumnFamilyMemTablesImpl to provide WriteBatch a way to access
+// memtables of different column families (specified by ID in the write batch)
+class ColumnFamilyMemTablesImpl : public ColumnFamilyMemTables {
+ public:
+  explicit ColumnFamilyMemTablesImpl(ColumnFamilySet* column_family_set)
+      : column_family_set_(column_family_set), current_(nullptr) {}
+
+  // sets current_ to ColumnFamilyData with column_family_id
+  // returns false if column family doesn't exist
+  bool Seek(uint32_t column_family_id) override;
+
+  // Returns log number of the selected column family
+  uint64_t GetLogNumber() const override;
+
+  // REQUIRES: Seek() called first
+  virtual MemTable* GetMemTable() const override;
+
+  // Returns options for selected column family
+  // REQUIRES: Seek() called first
+  virtual const Options* GetOptions() const override;
+
+  // Returns column family handle for the selected column family
+  virtual ColumnFamilyHandle* GetColumnFamilyHandle() override;
+
+ private:
+  ColumnFamilySet* column_family_set_;
+  ColumnFamilyData* current_;
+  ColumnFamilyHandleInternal handle_;
+};
+
+}  // namespace rocksdb

db/column_family_test.cc

@@ -0,0 +1,945 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include <algorithm>
+#include <vector>
+#include <string>
+
+#include "db/db_impl.h"
+#include "rocksdb/env.h"
+#include "rocksdb/db.h"
+#include "util/testharness.h"
+#include "util/testutil.h"
+#include "util/coding.h"
+#include "utilities/merge_operators.h"
+
+namespace rocksdb {
+
+namespace {
+std::string RandomString(Random* rnd, int len) {
+  std::string r;
+  test::RandomString(rnd, len, &r);
+  return r;
+}
+}  // anonymous namespace
+
+// counts how many operations were performed
+class EnvCounter : public EnvWrapper {
+ public:
+  explicit EnvCounter(Env* base)
+      : EnvWrapper(base), num_new_writable_file_(0) {}
+  int GetNumberOfNewWritableFileCalls() {
+    return num_new_writable_file_;
+  }
+  Status NewWritableFile(const std::string& f, unique_ptr<WritableFile>* r,
+                         const EnvOptions& soptions) {
+    ++num_new_writable_file_;
+    return EnvWrapper::NewWritableFile(f, r, soptions);
+  }
+
+ private:
+  int num_new_writable_file_;
+};
+
+class ColumnFamilyTest {
+ public:
+  ColumnFamilyTest() : rnd_(139) {
+    env_ = new EnvCounter(Env::Default());
+    dbname_ = test::TmpDir() + "/column_family_test";
+    db_options_.create_if_missing = true;
+    db_options_.env = env_;
+    DestroyDB(dbname_, Options(db_options_, column_family_options_));
+  }
+
+  ~ColumnFamilyTest() {
+    delete env_;
+  }
+
+  void Close() {
+    for (auto h : handles_) {
+      delete h;
+    }
+    handles_.clear();
+    names_.clear();
+    delete db_;
+    db_ = nullptr;
+  }
+
+  Status TryOpen(std::vector<std::string> cf,
+                 std::vector<ColumnFamilyOptions> options = {}) {
+    std::vector<ColumnFamilyDescriptor> column_families;
+    names_.clear();
+    for (size_t i = 0; i < cf.size(); ++i) {
+      column_families.push_back(ColumnFamilyDescriptor(
+          cf[i], options.size() == 0 ? column_family_options_ : options[i]));
+      names_.push_back(cf[i]);
+    }
+    return DB::Open(db_options_, dbname_, column_families, &handles_, &db_);
+  }
+
+  Status OpenReadOnly(std::vector<std::string> cf,
+                         std::vector<ColumnFamilyOptions> options = {}) {
+    std::vector<ColumnFamilyDescriptor> column_families;
+    names_.clear();
+    for (size_t i = 0; i < cf.size(); ++i) {
+      column_families.push_back(ColumnFamilyDescriptor(
+          cf[i], options.size() == 0 ? column_family_options_ : options[i]));
+      names_.push_back(cf[i]);
+    }
+    return DB::OpenForReadOnly(db_options_, dbname_, column_families, &handles_,
+                               &db_);
+  }
+
+  void AssertOpenReadOnly(std::vector<std::string> cf,
+                    std::vector<ColumnFamilyOptions> options = {}) {
+    ASSERT_OK(OpenReadOnly(cf, options));
+  }
+
+
+  void Open(std::vector<std::string> cf,
+            std::vector<ColumnFamilyOptions> options = {}) {
+    ASSERT_OK(TryOpen(cf, options));
+  }
+
+  void Open() {
+    Open({"default"});
+  }
+
+  DBImpl* dbfull() { return reinterpret_cast<DBImpl*>(db_); }
+
+  int GetProperty(int cf, std::string property) {
+    std::string value;
+    ASSERT_TRUE(dbfull()->GetProperty(handles_[cf], property, &value));
+    return std::stoi(value);
+  }
+
+  void Destroy() {
+    for (auto h : handles_) {
+      delete h;
+    }
+    handles_.clear();
+    names_.clear();
+    delete db_;
+    db_ = nullptr;
+    ASSERT_OK(DestroyDB(dbname_, Options(db_options_, column_family_options_)));
+  }
+
+  void CreateColumnFamilies(
+      const std::vector<std::string>& cfs,
+      const std::vector<ColumnFamilyOptions> options = {}) {
+    int cfi = handles_.size();
+    handles_.resize(cfi + cfs.size());
+    names_.resize(cfi + cfs.size());
+    for (size_t i = 0; i < cfs.size(); ++i) {
+      ASSERT_OK(db_->CreateColumnFamily(
+          options.size() == 0 ? column_family_options_ : options[i], cfs[i],
+          &handles_[cfi]));
+      names_[cfi] = cfs[i];
+      cfi++;
+    }
+  }
+
+  void Reopen(const std::vector<ColumnFamilyOptions> options = {}) {
+    std::vector<std::string> names;
+    for (auto name : names_) {
+      if (name != "") {
+        names.push_back(name);
+      }
+    }
+    Close();
+    assert(options.size() == 0 || names.size() == options.size());
+    Open(names, options);
+  }
+
+  void CreateColumnFamiliesAndReopen(const std::vector<std::string>& cfs) {
+    CreateColumnFamilies(cfs);
+    Reopen();
+  }
+
+  void DropColumnFamilies(const std::vector<int>& cfs) {
+    for (auto cf : cfs) {
+      ASSERT_OK(db_->DropColumnFamily(handles_[cf]));
+      delete handles_[cf];
+      handles_[cf] = nullptr;
+      names_[cf] = "";
+    }
+  }
+
+  void PutRandomData(int cf, int num, int key_value_size) {
+    for (int i = 0; i < num; ++i) {
+      // 10 bytes for key, rest is value
+      ASSERT_OK(Put(cf, test::RandomKey(&rnd_, 10),
+                    RandomString(&rnd_, key_value_size - 10)));
+    }
+  }
+
+  void WaitForFlush(int cf) {
+    ASSERT_OK(dbfull()->TEST_WaitForFlushMemTable(handles_[cf]));
+  }
+
+  void WaitForCompaction() { ASSERT_OK(dbfull()->TEST_WaitForCompact()); }
+
+  Status Put(int cf, const std::string& key, const std::string& value) {
+    return db_->Put(WriteOptions(), handles_[cf], Slice(key), Slice(value));
+  }
+  Status Merge(int cf, const std::string& key, const std::string& value) {
+    return db_->Merge(WriteOptions(), handles_[cf], Slice(key), Slice(value));
+  }
+  Status Flush(int cf) {
+    return db_->Flush(FlushOptions(), handles_[cf]);
+  }
+
+  std::string Get(int cf, const std::string& key) {
+    ReadOptions options;
+    options.verify_checksums = true;
+    std::string result;
+    Status s = db_->Get(options, handles_[cf], Slice(key), &result);
+    if (s.IsNotFound()) {
+      result = "NOT_FOUND";
+    } else if (!s.ok()) {
+      result = s.ToString();
+    }
+    return result;
+  }
+
+  void CompactAll(int cf) {
+    ASSERT_OK(db_->CompactRange(handles_[cf], nullptr, nullptr));
+  }
+
+  void Compact(int cf, const Slice& start, const Slice& limit) {
+    ASSERT_OK(db_->CompactRange(handles_[cf], &start, &limit));
+  }
+
+  int NumTableFilesAtLevel(int level, int cf) {
+    return GetProperty(cf,
+                       "rocksdb.num-files-at-level" + std::to_string(level));
+  }
+
+  // Return spread of files per level
+  std::string FilesPerLevel(int cf) {
+    std::string result;
+    int last_non_zero_offset = 0;
+    for (int level = 0; level < dbfull()->NumberLevels(handles_[cf]); level++) {
+      int f = NumTableFilesAtLevel(level, cf);
+      char buf[100];
+      snprintf(buf, sizeof(buf), "%s%d", (level ? "," : ""), f);
+      result += buf;
+      if (f > 0) {
+        last_non_zero_offset = result.size();
+      }
+    }
+    result.resize(last_non_zero_offset);
+    return result;
+  }
+
+  int CountLiveFiles() {
+    std::vector<LiveFileMetaData> metadata;
+    db_->GetLiveFilesMetaData(&metadata);
+    return static_cast<int>(metadata.size());
+  }
+
+  // Do n memtable flushes, each of which produces an sstable
+  // covering the range [small,large].
+  void MakeTables(int cf, int n, const std::string& small,
+                  const std::string& large) {
+    for (int i = 0; i < n; i++) {
+      ASSERT_OK(Put(cf, small, "begin"));
+      ASSERT_OK(Put(cf, large, "end"));
+      ASSERT_OK(db_->Flush(FlushOptions(), handles_[cf]));
+    }
+  }
+
+  int CountLiveLogFiles() {
+    int micros_wait_for_log_deletion = 20000;
+    env_->SleepForMicroseconds(micros_wait_for_log_deletion);
+    int ret = 0;
+    VectorLogPtr wal_files;
+    Status s;
+    // GetSortedWalFiles is a flakey function -- it gets all the wal_dir
+    // children files and then later checks for their existance. if some of the
+    // log files doesn't exist anymore, it reports an error. it does all of this
+    // without DB mutex held, so if a background process deletes the log file
+    // while the function is being executed, it returns an error. We retry the
+    // function 10 times to avoid the error failing the test
+    for (int retries = 0; retries < 10; ++retries) {
+      wal_files.clear();
+      s = db_->GetSortedWalFiles(wal_files);
+      if (s.ok()) {
+        break;
+      }
+    }
+    ASSERT_OK(s);
+    for (const auto& wal : wal_files) {
+      if (wal->Type() == kAliveLogFile) {
+        ++ret;
+      }
+    }
+    return ret;
+  }
+
+  void AssertNumberOfImmutableMemtables(std::vector<int> num_per_cf) {
+    assert(num_per_cf.size() == handles_.size());
+
+    for (size_t i = 0; i < num_per_cf.size(); ++i) {
+      ASSERT_EQ(num_per_cf[i],
+                GetProperty(i, "rocksdb.num-immutable-mem-table"));
+    }
+  }
+
+  void CopyFile(const std::string& source, const std::string& destination,
+                uint64_t size = 0) {
+    const EnvOptions soptions;
+    unique_ptr<SequentialFile> srcfile;
+    ASSERT_OK(env_->NewSequentialFile(source, &srcfile, soptions));
+    unique_ptr<WritableFile> destfile;
+    ASSERT_OK(env_->NewWritableFile(destination, &destfile, soptions));
+
+    if (size == 0) {
+      // default argument means copy everything
+      ASSERT_OK(env_->GetFileSize(source, &size));
+    }
+
+    char buffer[4096];
+    Slice slice;
+    while (size > 0) {
+      uint64_t one = std::min(uint64_t(sizeof(buffer)), size);
+      ASSERT_OK(srcfile->Read(one, &slice, buffer));
+      ASSERT_OK(destfile->Append(slice));
+      size -= slice.size();
+    }
+    ASSERT_OK(destfile->Close());
+  }
+
+  std::vector<ColumnFamilyHandle*> handles_;
+  std::vector<std::string> names_;
+  ColumnFamilyOptions column_family_options_;
+  DBOptions db_options_;
+  std::string dbname_;
+  DB* db_ = nullptr;
+  EnvCounter* env_;
+  Random rnd_;
+};
+
+TEST(ColumnFamilyTest, DontReuseColumnFamilyID) {
+  for (int iter = 0; iter < 3; ++iter) {
+    Open();
+    CreateColumnFamilies({"one", "two", "three"});
+    for (size_t i = 0; i < handles_.size(); ++i) {
+      auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(handles_[i]);
+      ASSERT_EQ(i, cfh->GetID());
+    }
+    if (iter == 1) {
+      Reopen();
+    }
+    DropColumnFamilies({3});
+    Reopen();
+    if (iter == 2) {
+      // this tests if max_column_family is correctly persisted with
+      // WriteSnapshot()
+      Reopen();
+    }
+    CreateColumnFamilies({"three2"});
+    // ID 3 that was used for dropped column family "three" should not be reused
+    auto cfh3 = reinterpret_cast<ColumnFamilyHandleImpl*>(handles_[3]);
+    ASSERT_EQ(4U, cfh3->GetID());
+    Close();
+    Destroy();
+  }
+}
+
+
+TEST(ColumnFamilyTest, AddDrop) {
+  Open();
+  CreateColumnFamilies({"one", "two", "three"});
+  ASSERT_EQ("NOT_FOUND", Get(1, "fodor"));
+  ASSERT_EQ("NOT_FOUND", Get(2, "fodor"));
+  DropColumnFamilies({2});
+  ASSERT_EQ("NOT_FOUND", Get(1, "fodor"));
+  CreateColumnFamilies({"four"});
+  ASSERT_EQ("NOT_FOUND", Get(3, "fodor"));
+  ASSERT_OK(Put(1, "fodor", "mirko"));
+  ASSERT_EQ("mirko", Get(1, "fodor"));
+  ASSERT_EQ("NOT_FOUND", Get(3, "fodor"));
+  Close();
+  ASSERT_TRUE(TryOpen({"default"}).IsInvalidArgument());
+  Open({"default", "one", "three", "four"});
+  DropColumnFamilies({1});
+  Reopen();
+  Close();
+
+  std::vector<std::string> families;
+  ASSERT_OK(DB::ListColumnFamilies(db_options_, dbname_, &families));
+  sort(families.begin(), families.end());
+  ASSERT_TRUE(families ==
+              std::vector<std::string>({"default", "four", "three"}));
+}
+
+TEST(ColumnFamilyTest, DropTest) {
+  // first iteration - dont reopen DB before dropping
+  // second iteration - reopen DB before dropping
+  for (int iter = 0; iter < 2; ++iter) {
+    Open({"default"});
+    CreateColumnFamiliesAndReopen({"pikachu"});
+    for (int i = 0; i < 100; ++i) {
+      ASSERT_OK(Put(1, std::to_string(i), "bar" + std::to_string(i)));
+    }
+    ASSERT_OK(Flush(1));
+
+    if (iter == 1) {
+      Reopen();
+    }
+    ASSERT_EQ("bar1", Get(1, "1"));
+
+    ASSERT_EQ(CountLiveFiles(), 1);
+    DropColumnFamilies({1});
+    // make sure that all files are deleted when we drop the column family
+    ASSERT_EQ(CountLiveFiles(), 0);
+    Destroy();
+  }
+}
+
+TEST(ColumnFamilyTest, WriteBatchFailure) {
+  Open();
+  CreateColumnFamiliesAndReopen({"one", "two"});
+  WriteBatch batch;
+  batch.Put(handles_[1], Slice("non-existing"), Slice("column-family"));
+  ASSERT_OK(db_->Write(WriteOptions(), &batch));
+  DropColumnFamilies({1});
+  Status s = db_->Write(WriteOptions(), &batch);
+  ASSERT_TRUE(s.IsInvalidArgument());
+  Close();
+}
+
+TEST(ColumnFamilyTest, ReadWrite) {
+  Open();
+  CreateColumnFamiliesAndReopen({"one", "two"});
+  ASSERT_OK(Put(0, "foo", "v1"));
+  ASSERT_OK(Put(0, "bar", "v2"));
+  ASSERT_OK(Put(1, "mirko", "v3"));
+  ASSERT_OK(Put(0, "foo", "v2"));
+  ASSERT_OK(Put(2, "fodor", "v5"));
+
+  for (int iter = 0; iter <= 3; ++iter) {
+    ASSERT_EQ("v2", Get(0, "foo"));
+    ASSERT_EQ("v2", Get(0, "bar"));
+    ASSERT_EQ("v3", Get(1, "mirko"));
+    ASSERT_EQ("v5", Get(2, "fodor"));
+    ASSERT_EQ("NOT_FOUND", Get(0, "fodor"));
+    ASSERT_EQ("NOT_FOUND", Get(1, "fodor"));
+    ASSERT_EQ("NOT_FOUND", Get(2, "foo"));
+    if (iter <= 1) {
+      Reopen();
+    }
+  }
+  Close();
+}
+
+TEST(ColumnFamilyTest, IgnoreRecoveredLog) {
+  std::string backup_logs = dbname_ + "/backup_logs";
+
+  // delete old files in backup_logs directory
+  ASSERT_OK(env_->CreateDirIfMissing(dbname_));
+  ASSERT_OK(env_->CreateDirIfMissing(backup_logs));
+  std::vector<std::string> old_files;
+  env_->GetChildren(backup_logs, &old_files);
+  for (auto& file : old_files) {
+    if (file != "." && file != "..") {
+      env_->DeleteFile(backup_logs + "/" + file);
+    }
+  }
+
+  column_family_options_.merge_operator =
+      MergeOperators::CreateUInt64AddOperator();
+  db_options_.wal_dir = dbname_ + "/logs";
+  Destroy();
+  Open();
+  CreateColumnFamilies({"cf1", "cf2"});
+
+  // fill up the DB
+  std::string one, two, three;
+  PutFixed64(&one, 1);
+  PutFixed64(&two, 2);
+  PutFixed64(&three, 3);
+  ASSERT_OK(Merge(0, "foo", one));
+  ASSERT_OK(Merge(1, "mirko", one));
+  ASSERT_OK(Merge(0, "foo", one));
+  ASSERT_OK(Merge(2, "bla", one));
+  ASSERT_OK(Merge(2, "fodor", one));
+  ASSERT_OK(Merge(0, "bar", one));
+  ASSERT_OK(Merge(2, "bla", one));
+  ASSERT_OK(Merge(1, "mirko", two));
+  ASSERT_OK(Merge(1, "franjo", one));
+
+  // copy the logs to backup
+  std::vector<std::string> logs;
+  env_->GetChildren(db_options_.wal_dir, &logs);
+  for (auto& log : logs) {
+    if (log != ".." && log != ".") {
+      CopyFile(db_options_.wal_dir + "/" + log, backup_logs + "/" + log);
+    }
+  }
+
+  // recover the DB
+  Close();
+
+  // 1. check consistency
+  // 2. copy the logs from backup back to WAL dir. if the recovery happens
+  // again on the same log files, this should lead to incorrect results
+  // due to applying merge operator twice
+  // 3. check consistency
+  for (int iter = 0; iter < 2; ++iter) {
+    // assert consistency
+    Open({"default", "cf1", "cf2"});
+    ASSERT_EQ(two, Get(0, "foo"));
+    ASSERT_EQ(one, Get(0, "bar"));
+    ASSERT_EQ(three, Get(1, "mirko"));
+    ASSERT_EQ(one, Get(1, "franjo"));
+    ASSERT_EQ(one, Get(2, "fodor"));
+    ASSERT_EQ(two, Get(2, "bla"));
+    Close();
+
+    if (iter == 0) {
+      // copy the logs from backup back to wal dir
+      for (auto& log : logs) {
+        if (log != ".." && log != ".") {
+          CopyFile(backup_logs + "/" + log, db_options_.wal_dir + "/" + log);
+        }
+      }
+    }
+  }
+}
+
+TEST(ColumnFamilyTest, FlushTest) {
+  Open();
+  CreateColumnFamiliesAndReopen({"one", "two"});
+  ASSERT_OK(Put(0, "foo", "v1"));
+  ASSERT_OK(Put(0, "bar", "v2"));
+  ASSERT_OK(Put(1, "mirko", "v3"));
+  ASSERT_OK(Put(0, "foo", "v2"));
+  ASSERT_OK(Put(2, "fodor", "v5"));
+  for (int i = 0; i < 3; ++i) {
+    Flush(i);
+  }
+  Reopen();
+
+  for (int iter = 0; iter <= 2; ++iter) {
+    ASSERT_EQ("v2", Get(0, "foo"));
+    ASSERT_EQ("v2", Get(0, "bar"));
+    ASSERT_EQ("v3", Get(1, "mirko"));
+    ASSERT_EQ("v5", Get(2, "fodor"));
+    ASSERT_EQ("NOT_FOUND", Get(0, "fodor"));
+    ASSERT_EQ("NOT_FOUND", Get(1, "fodor"));
+    ASSERT_EQ("NOT_FOUND", Get(2, "foo"));
+    if (iter <= 1) {
+      Reopen();
+    }
+  }
+  Close();
+}
+
+// Makes sure that obsolete log files get deleted
+TEST(ColumnFamilyTest, LogDeletionTest) {
+  db_options_.max_total_wal_size = std::numeric_limits<uint64_t>::max();
+  column_family_options_.write_buffer_size = 100000;  // 100KB
+  Open();
+  CreateColumnFamilies({"one", "two", "three", "four"});
+  // Each bracket is one log file. if number is in (), it means
+  // we don't need it anymore (it's been flushed)
+  // []
+  ASSERT_EQ(CountLiveLogFiles(), 0);
+  PutRandomData(0, 1, 100);
+  // [0]
+  PutRandomData(1, 1, 100);
+  // [0, 1]
+  PutRandomData(1, 1000, 100);
+  WaitForFlush(1);
+  // [0, (1)] [1]
+  ASSERT_EQ(CountLiveLogFiles(), 2);
+  PutRandomData(0, 1, 100);
+  // [0, (1)] [0, 1]
+  ASSERT_EQ(CountLiveLogFiles(), 2);
+  PutRandomData(2, 1, 100);
+  // [0, (1)] [0, 1, 2]
+  PutRandomData(2, 1000, 100);
+  WaitForFlush(2);
+  // [0, (1)] [0, 1, (2)] [2]
+  ASSERT_EQ(CountLiveLogFiles(), 3);
+  PutRandomData(2, 1000, 100);
+  WaitForFlush(2);
+  // [0, (1)] [0, 1, (2)] [(2)] [2]
+  ASSERT_EQ(CountLiveLogFiles(), 4);
+  PutRandomData(3, 1, 100);
+  // [0, (1)] [0, 1, (2)] [(2)] [2, 3]
+  PutRandomData(1, 1, 100);
+  // [0, (1)] [0, 1, (2)] [(2)] [1, 2, 3]
+  ASSERT_EQ(CountLiveLogFiles(), 4);
+  PutRandomData(1, 1000, 100);
+  WaitForFlush(1);
+  // [0, (1)] [0, (1), (2)] [(2)] [(1), 2, 3] [1]
+  ASSERT_EQ(CountLiveLogFiles(), 5);
+  PutRandomData(0, 1000, 100);
+  WaitForFlush(0);
+  // [(0), (1)] [(0), (1), (2)] [(2)] [(1), 2, 3] [1, (0)] [0]
+  // delete obsolete logs -->
+  // [(1), 2, 3] [1, (0)] [0]
+  ASSERT_EQ(CountLiveLogFiles(), 3);
+  PutRandomData(0, 1000, 100);
+  WaitForFlush(0);
+  // [(1), 2, 3] [1, (0)], [(0)] [0]
+  ASSERT_EQ(CountLiveLogFiles(), 4);
+  PutRandomData(1, 1000, 100);
+  WaitForFlush(1);
+  // [(1), 2, 3] [(1), (0)] [(0)] [0, (1)] [1]
+  ASSERT_EQ(CountLiveLogFiles(), 5);
+  PutRandomData(2, 1000, 100);
+  WaitForFlush(2);
+  // [(1), (2), 3] [(1), (0)] [(0)] [0, (1)] [1, (2)], [2]
+  ASSERT_EQ(CountLiveLogFiles(), 6);
+  PutRandomData(3, 1000, 100);
+  WaitForFlush(3);
+  // [(1), (2), (3)] [(1), (0)] [(0)] [0, (1)] [1, (2)], [2, (3)] [3]
+  // delete obsolete logs -->
+  // [0, (1)] [1, (2)], [2, (3)] [3]
+  ASSERT_EQ(CountLiveLogFiles(), 4);
+  Close();
+}
+
+// Makes sure that obsolete log files get deleted
+TEST(ColumnFamilyTest, DifferentWriteBufferSizes) {
+  // disable flushing stale column families
+  db_options_.max_total_wal_size = std::numeric_limits<uint64_t>::max();
+  Open();
+  CreateColumnFamilies({"one", "two", "three"});
+  ColumnFamilyOptions default_cf, one, two, three;
+  // setup options. all column families have max_write_buffer_number setup to 10
+  // "default" -> 100KB memtable, start flushing immediatelly
+  // "one" -> 200KB memtable, start flushing with two immutable memtables
+  // "two" -> 1MB memtable, start flushing with three immutable memtables
+  // "three" -> 90KB memtable, start flushing with four immutable memtables
+  default_cf.write_buffer_size = 100000;
+  default_cf.max_write_buffer_number = 10;
+  default_cf.min_write_buffer_number_to_merge = 1;
+  one.write_buffer_size = 200000;
+  one.max_write_buffer_number = 10;
+  one.min_write_buffer_number_to_merge = 2;
+  two.write_buffer_size = 1000000;
+  two.max_write_buffer_number = 10;
+  two.min_write_buffer_number_to_merge = 3;
+  three.write_buffer_size = 90000;
+  three.max_write_buffer_number = 10;
+  three.min_write_buffer_number_to_merge = 4;
+
+  Reopen({default_cf, one, two, three});
+
+  int micros_wait_for_flush = 10000;
+  PutRandomData(0, 100, 1000);
+  WaitForFlush(0);
+  AssertNumberOfImmutableMemtables({0, 0, 0, 0});
+  ASSERT_EQ(CountLiveLogFiles(), 1);
+  PutRandomData(1, 200, 1000);
+  env_->SleepForMicroseconds(micros_wait_for_flush);
+  AssertNumberOfImmutableMemtables({0, 1, 0, 0});
+  ASSERT_EQ(CountLiveLogFiles(), 2);
+  PutRandomData(2, 1000, 1000);
+  env_->SleepForMicroseconds(micros_wait_for_flush);
+  AssertNumberOfImmutableMemtables({0, 1, 1, 0});
+  ASSERT_EQ(CountLiveLogFiles(), 3);
+  PutRandomData(2, 1000, 1000);
+  env_->SleepForMicroseconds(micros_wait_for_flush);
+  AssertNumberOfImmutableMemtables({0, 1, 2, 0});
+  ASSERT_EQ(CountLiveLogFiles(), 4);
+  PutRandomData(3, 90, 1000);
+  env_->SleepForMicroseconds(micros_wait_for_flush);
+  AssertNumberOfImmutableMemtables({0, 1, 2, 1});
+  ASSERT_EQ(CountLiveLogFiles(), 5);
+  PutRandomData(3, 90, 1000);
+  env_->SleepForMicroseconds(micros_wait_for_flush);
+  AssertNumberOfImmutableMemtables({0, 1, 2, 2});
+  ASSERT_EQ(CountLiveLogFiles(), 6);
+  PutRandomData(3, 90, 1000);
+  env_->SleepForMicroseconds(micros_wait_for_flush);
+  AssertNumberOfImmutableMemtables({0, 1, 2, 3});
+  ASSERT_EQ(CountLiveLogFiles(), 7);
+  PutRandomData(0, 100, 1000);
+  WaitForFlush(0);
+  AssertNumberOfImmutableMemtables({0, 1, 2, 3});
+  ASSERT_EQ(CountLiveLogFiles(), 8);
+  PutRandomData(2, 100, 10000);
+  WaitForFlush(2);
+  AssertNumberOfImmutableMemtables({0, 1, 0, 3});
+  ASSERT_EQ(CountLiveLogFiles(), 9);
+  PutRandomData(3, 90, 1000);
+  WaitForFlush(3);
+  AssertNumberOfImmutableMemtables({0, 1, 0, 0});
+  ASSERT_EQ(CountLiveLogFiles(), 10);
+  PutRandomData(3, 90, 1000);
+  env_->SleepForMicroseconds(micros_wait_for_flush);
+  AssertNumberOfImmutableMemtables({0, 1, 0, 1});
+  ASSERT_EQ(CountLiveLogFiles(), 11);
+  PutRandomData(1, 200, 1000);
+  WaitForFlush(1);
+  AssertNumberOfImmutableMemtables({0, 0, 0, 1});
+  ASSERT_EQ(CountLiveLogFiles(), 5);
+  PutRandomData(3, 90*6, 1000);
+  WaitForFlush(3);
+  AssertNumberOfImmutableMemtables({0, 0, 0, 0});
+  ASSERT_EQ(CountLiveLogFiles(), 12);
+  PutRandomData(0, 100, 1000);
+  WaitForFlush(0);
+  AssertNumberOfImmutableMemtables({0, 0, 0, 0});
+  ASSERT_EQ(CountLiveLogFiles(), 12);
+  PutRandomData(2, 3*100, 10000);
+  WaitForFlush(2);
+  AssertNumberOfImmutableMemtables({0, 0, 0, 0});
+  ASSERT_EQ(CountLiveLogFiles(), 12);
+  PutRandomData(1, 2*200, 1000);
+  WaitForFlush(1);
+  AssertNumberOfImmutableMemtables({0, 0, 0, 0});
+  ASSERT_EQ(CountLiveLogFiles(), 7);
+  Close();
+}
+
+TEST(ColumnFamilyTest, DifferentMergeOperators) {
+  Open();
+  CreateColumnFamilies({"first", "second"});
+  ColumnFamilyOptions default_cf, first, second;
+  first.merge_operator = MergeOperators::CreateUInt64AddOperator();
+  second.merge_operator = MergeOperators::CreateStringAppendOperator();
+  Reopen({default_cf, first, second});
+
+  std::string one, two, three;
+  PutFixed64(&one, 1);
+  PutFixed64(&two, 2);
+  PutFixed64(&three, 3);
+
+  ASSERT_OK(Put(0, "foo", two));
+  ASSERT_OK(Put(0, "foo", one));
+  ASSERT_TRUE(Merge(0, "foo", two).IsNotSupported());
+  ASSERT_EQ(Get(0, "foo"), one);
+
+  ASSERT_OK(Put(1, "foo", two));
+  ASSERT_OK(Put(1, "foo", one));
+  ASSERT_OK(Merge(1, "foo", two));
+  ASSERT_EQ(Get(1, "foo"), three);
+
+  ASSERT_OK(Put(2, "foo", two));
+  ASSERT_OK(Put(2, "foo", one));
+  ASSERT_OK(Merge(2, "foo", two));
+  ASSERT_EQ(Get(2, "foo"), one + "," + two);
+  Close();
+}
+
+TEST(ColumnFamilyTest, DifferentCompactionStyles) {
+  Open();
+  CreateColumnFamilies({"one", "two"});
+  ColumnFamilyOptions default_cf, one, two;
+  db_options_.max_open_files = 20;  // only 10 files in file cache
+  db_options_.disableDataSync = true;
+
+  default_cf.compaction_style = kCompactionStyleLevel;
+  default_cf.num_levels = 3;
+  default_cf.write_buffer_size = 64 << 10;  // 64KB
+  default_cf.target_file_size_base = 30 << 10;
+  default_cf.filter_policy = nullptr;
+  default_cf.no_block_cache = true;
+  default_cf.source_compaction_factor = 100;
+
+  one.compaction_style = kCompactionStyleUniversal;
+  // trigger compaction if there are >= 4 files
+  one.level0_file_num_compaction_trigger = 4;
+  one.write_buffer_size = 100000;
+
+  two.compaction_style = kCompactionStyleLevel;
+  two.num_levels = 4;
+  two.max_mem_compaction_level = 0;
+  two.level0_file_num_compaction_trigger = 3;
+  two.write_buffer_size = 100000;
+
+  Reopen({default_cf, one, two});
+
+  // SETUP column family "one" -- universal style
+  for (int i = 0; i < one.level0_file_num_compaction_trigger - 1; ++i) {
+    PutRandomData(1, 11, 10000);
+    WaitForFlush(1);
+    ASSERT_EQ(std::to_string(i + 1), FilesPerLevel(1));
+  }
+
+  // SETUP column family "two" -- level style with 4 levels
+  for (int i = 0; i < two.level0_file_num_compaction_trigger - 1; ++i) {
+    PutRandomData(2, 15, 10000);
+    WaitForFlush(2);
+    ASSERT_EQ(std::to_string(i + 1), FilesPerLevel(2));
+  }
+
+  // TRIGGER compaction "one"
+  PutRandomData(1, 12, 10000);
+
+  // TRIGGER compaction "two"
+  PutRandomData(2, 10, 10000);
+
+  // WAIT for compactions
+  WaitForCompaction();
+
+  // VERIFY compaction "one"
+  ASSERT_EQ("1", FilesPerLevel(1));
+
+  // VERIFY compaction "two"
+  ASSERT_EQ("0,1", FilesPerLevel(2));
+  CompactAll(2);
+  ASSERT_EQ("0,1", FilesPerLevel(2));
+
+  Close();
+}
+
+namespace {
+std::string IterStatus(Iterator* iter) {
+  std::string result;
+  if (iter->Valid()) {
+    result = iter->key().ToString() + "->" + iter->value().ToString();
+  } else {
+    result = "(invalid)";
+  }
+  return result;
+}
+}  // anonymous namespace
+
+TEST(ColumnFamilyTest, NewIteratorsTest) {
+  // iter == 0 -- no tailing
+  // iter == 2 -- tailing
+  for (int iter = 0; iter < 2; ++iter) {
+    Open();
+    CreateColumnFamiliesAndReopen({"one", "two"});
+    ASSERT_OK(Put(0, "a", "b"));
+    ASSERT_OK(Put(1, "b", "a"));
+    ASSERT_OK(Put(2, "c", "m"));
+    ASSERT_OK(Put(2, "v", "t"));
+    std::vector<Iterator*> iterators;
+    ReadOptions options;
+    options.tailing = (iter == 1);
+    ASSERT_OK(db_->NewIterators(options, handles_, &iterators));
+
+    for (auto it : iterators) {
+      it->SeekToFirst();
+    }
+    ASSERT_EQ(IterStatus(iterators[0]), "a->b");
+    ASSERT_EQ(IterStatus(iterators[1]), "b->a");
+    ASSERT_EQ(IterStatus(iterators[2]), "c->m");
+
+    ASSERT_OK(Put(1, "x", "x"));
+
+    for (auto it : iterators) {
+      it->Next();
+    }
+
+    ASSERT_EQ(IterStatus(iterators[0]), "(invalid)");
+    if (iter == 0) {
+      // no tailing
+      ASSERT_EQ(IterStatus(iterators[1]), "(invalid)");
+    } else {
+      // tailing
+      ASSERT_EQ(IterStatus(iterators[1]), "x->x");
+    }
+    ASSERT_EQ(IterStatus(iterators[2]), "v->t");
+
+    for (auto it : iterators) {
+      delete it;
+    }
+    Destroy();
+  }
+}
+
+TEST(ColumnFamilyTest, ReadOnlyDBTest) {
+  Open();
+  CreateColumnFamiliesAndReopen({"one", "two", "three", "four"});
+  ASSERT_OK(Put(1, "foo", "bla"));
+  ASSERT_OK(Put(2, "foo", "blabla"));
+  ASSERT_OK(Put(3, "foo", "blablabla"));
+  ASSERT_OK(Put(4, "foo", "blablablabla"));
+
+  DropColumnFamilies({2});
+  Close();
+  // open only a subset of column families
+  AssertOpenReadOnly({"default", "one", "four"});
+  ASSERT_EQ("NOT_FOUND", Get(0, "foo"));
+  ASSERT_EQ("bla", Get(1, "foo"));
+  ASSERT_EQ("blablablabla", Get(2, "foo"));
+
+  Close();
+  // can't open dropped column family
+  Status s = OpenReadOnly({"default", "one", "two"});
+  ASSERT_TRUE(!s.ok());
+
+  // Can't open without specifying default column family
+  s = OpenReadOnly({"one", "four"});
+  ASSERT_TRUE(!s.ok());
+}
+
+TEST(ColumnFamilyTest, DontRollEmptyLogs) {
+  Open();
+  CreateColumnFamiliesAndReopen({"one", "two", "three", "four"});
+
+  for (size_t i = 0; i < handles_.size(); ++i) {
+    PutRandomData(i, 10, 100);
+  }
+  int num_writable_file_start = env_->GetNumberOfNewWritableFileCalls();
+  // this will trigger the flushes
+  ASSERT_OK(db_->Write(WriteOptions(), nullptr));
+
+  for (int i = 0; i < 4; ++i) {
+    dbfull()->TEST_WaitForFlushMemTable(handles_[i]);
+  }
+  int total_new_writable_files =
+      env_->GetNumberOfNewWritableFileCalls() - num_writable_file_start;
+  ASSERT_EQ(static_cast<size_t>(total_new_writable_files), handles_.size() + 1);
+  Close();
+}
+
+TEST(ColumnFamilyTest, FlushStaleColumnFamilies) {
+  Open();
+  CreateColumnFamilies({"one", "two"});
+  ColumnFamilyOptions default_cf, one, two;
+  default_cf.write_buffer_size = 100000;  // small write buffer size
+  default_cf.disable_auto_compactions = true;
+  one.disable_auto_compactions = true;
+  two.disable_auto_compactions = true;
+  db_options_.max_total_wal_size = 210000;
+
+  Reopen({default_cf, one, two});
+
+  PutRandomData(2, 1, 10);  // 10 bytes
+  for (int i = 0; i < 2; ++i) {
+    PutRandomData(0, 100, 1000);  // flush
+    WaitForFlush(0);
+    ASSERT_EQ(i + 1, CountLiveFiles());
+  }
+  // third flush. now, CF [two] should be detected as stale and flushed
+  // column family 1 should not be flushed since it's empty
+  PutRandomData(0, 100, 1000);  // flush
+  WaitForFlush(0);
+  WaitForFlush(2);
+  // 3 files for default column families, 1 file for column family [two], zero
+  // files for column family [one], because it's empty
+  ASSERT_EQ(4, CountLiveFiles());
+  Close();
+}
+
+TEST(ColumnFamilyTest, CreateMissingColumnFamilies) {
+  Status s = TryOpen({"one", "two"});
+  ASSERT_TRUE(!s.ok());
+  db_options_.create_missing_column_families = true;
+  s = TryOpen({"default", "one", "two"});
+  ASSERT_TRUE(s.ok());
+  Close();
+}
+
+}  // namespace rocksdb
+
+int main(int argc, char** argv) {
+  return rocksdb::test::RunAllTests();
+}

db/compaction.cc

@@ -0,0 +1,271 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "db/compaction.h"
+
+#define __STDC_FORMAT_MACROS
+#include <inttypes.h>
+#include <vector>
+
+#include "db/column_family.h"
+#include "util/logging.h"
+
+namespace rocksdb {
+
+static uint64_t TotalFileSize(const std::vector<FileMetaData*>& files) {
+  uint64_t sum = 0;
+  for (size_t i = 0; i < files.size() && files[i]; i++) {
+    sum += files[i]->fd.GetFileSize();
+  }
+  return sum;
+}
+
+Compaction::Compaction(Version* input_version, int level, int out_level,
+                       uint64_t target_file_size,
+                       uint64_t max_grandparent_overlap_bytes,
+                       uint32_t output_path_id,
+                       CompressionType output_compression, bool seek_compaction,
+                       bool deletion_compaction)
+    : level_(level),
+      out_level_(out_level),
+      max_output_file_size_(target_file_size),
+      max_grandparent_overlap_bytes_(max_grandparent_overlap_bytes),
+      input_version_(input_version),
+      number_levels_(input_version_->NumberLevels()),
+      cfd_(input_version_->cfd_),
+      output_path_id_(output_path_id),
+      output_compression_(output_compression),
+      seek_compaction_(seek_compaction),
+      deletion_compaction_(deletion_compaction),
+      grandparent_index_(0),
+      seen_key_(false),
+      overlapped_bytes_(0),
+      base_index_(-1),
+      parent_index_(-1),
+      score_(0),
+      bottommost_level_(false),
+      is_full_compaction_(false),
+      is_manual_compaction_(false),
+      level_ptrs_(std::vector<size_t>(number_levels_)) {
+
+  cfd_->Ref();
+  input_version_->Ref();
+  edit_ = new VersionEdit();
+  edit_->SetColumnFamily(cfd_->GetID());
+  for (int i = 0; i < number_levels_; i++) {
+    level_ptrs_[i] = 0;
+  }
+}
+
+Compaction::~Compaction() {
+  delete edit_;
+  if (input_version_ != nullptr) {
+    input_version_->Unref();
+  }
+  if (cfd_ != nullptr) {
+    if (cfd_->Unref()) {
+      delete cfd_;
+    }
+  }
+}
+
+bool Compaction::IsTrivialMove() const {
+  // Avoid a move if there is lots of overlapping grandparent data.
+  // Otherwise, the move could create a parent file that will require
+  // a very expensive merge later on.
+  // If level_== out_level_, the purpose is to force compaction filter to be
+  // applied to that level, and thus cannot be a trivia move.
+  return (level_ != out_level_ &&
+          num_input_files(0) == 1 &&
+          num_input_files(1) == 0 &&
+          TotalFileSize(grandparents_) <= max_grandparent_overlap_bytes_);
+}
+
+bool Compaction::IsDeletionCompaction() const { return deletion_compaction_; }
+
+void Compaction::AddInputDeletions(VersionEdit* edit) {
+  for (int which = 0; which < 2; which++) {
+    for (size_t i = 0; i < inputs_[which].size(); i++) {
+      edit->DeleteFile(level_ + which, inputs_[which][i]->fd.GetNumber());
+    }
+  }
+}
+
+bool Compaction::IsBaseLevelForKey(const Slice& user_key) {
+  assert(cfd_->options()->compaction_style != kCompactionStyleFIFO);
+  if (cfd_->options()->compaction_style == kCompactionStyleUniversal) {
+    return bottommost_level_;
+  }
+  // Maybe use binary search to find right entry instead of linear search?
+  const Comparator* user_cmp = cfd_->user_comparator();
+  for (int lvl = level_ + 2; lvl < number_levels_; lvl++) {
+    const std::vector<FileMetaData*>& files = input_version_->files_[lvl];
+    for (; level_ptrs_[lvl] < files.size(); ) {
+      FileMetaData* f = files[level_ptrs_[lvl]];
+      if (user_cmp->Compare(user_key, f->largest.user_key()) <= 0) {
+        // We've advanced far enough
+        if (user_cmp->Compare(user_key, f->smallest.user_key()) >= 0) {
+          // Key falls in this file's range, so definitely not base level
+          return false;
+        }
+        break;
+      }
+      level_ptrs_[lvl]++;
+    }
+  }
+  return true;
+}
+
+bool Compaction::ShouldStopBefore(const Slice& internal_key) {
+  // Scan to find earliest grandparent file that contains key.
+  const InternalKeyComparator* icmp = &cfd_->internal_comparator();
+  while (grandparent_index_ < grandparents_.size() &&
+      icmp->Compare(internal_key,
+                    grandparents_[grandparent_index_]->largest.Encode()) > 0) {
+    if (seen_key_) {
+      overlapped_bytes_ += grandparents_[grandparent_index_]->fd.GetFileSize();
+    }
+    assert(grandparent_index_ + 1 >= grandparents_.size() ||
+           icmp->Compare(grandparents_[grandparent_index_]->largest.Encode(),
+                         grandparents_[grandparent_index_+1]->smallest.Encode())
+                         < 0);
+    grandparent_index_++;
+  }
+  seen_key_ = true;
+
+  if (overlapped_bytes_ > max_grandparent_overlap_bytes_) {
+    // Too much overlap for current output; start new output
+    overlapped_bytes_ = 0;
+    return true;
+  } else {
+    return false;
+  }
+}
+
+// Mark (or clear) each file that is being compacted
+void Compaction::MarkFilesBeingCompacted(bool value) {
+  for (int i = 0; i < 2; i++) {
+    std::vector<FileMetaData*> v = inputs_[i];
+    for (unsigned int j = 0; j < inputs_[i].size(); j++) {
+      assert(value ? !inputs_[i][j]->being_compacted :
+                      inputs_[i][j]->being_compacted);
+      inputs_[i][j]->being_compacted = value;
+    }
+  }
+}
+
+// Is this compaction producing files at the bottommost level?
+void Compaction::SetupBottomMostLevel(bool isManual) {
+  assert(cfd_->options()->compaction_style != kCompactionStyleFIFO);
+  if (cfd_->options()->compaction_style == kCompactionStyleUniversal) {
+    // If universal compaction style is used and manual
+    // compaction is occuring, then we are guaranteed that
+    // all files will be picked in a single compaction
+    // run. We can safely set bottommost_level_ = true.
+    // If it is not manual compaction, then bottommost_level_
+    // is already set when the Compaction was created.
+    if (isManual) {
+      bottommost_level_ = true;
+    }
+    return;
+  }
+  bottommost_level_ = true;
+  for (int i = output_level() + 1; i < number_levels_; i++) {
+    if (input_version_->NumLevelFiles(i) > 0) {
+      bottommost_level_ = false;
+      break;
+    }
+  }
+}
+
+void Compaction::ReleaseInputs() {
+  if (input_version_ != nullptr) {
+    input_version_->Unref();
+    input_version_ = nullptr;
+  }
+  if (cfd_ != nullptr) {
+    if (cfd_->Unref()) {
+      delete cfd_;
+    }
+    cfd_ = nullptr;
+  }
+}
+
+void Compaction::ReleaseCompactionFiles(Status status) {
+  cfd_->compaction_picker()->ReleaseCompactionFiles(this, status);
+}
+
+void Compaction::ResetNextCompactionIndex() {
+  input_version_->ResetNextCompactionIndex(level_);
+}
+
+namespace {
+int InputSummary(const std::vector<FileMetaData*>& files, char* output,
+                 int len) {
+  *output = '\0';
+  int write = 0;
+  for (unsigned int i = 0; i < files.size(); i++) {
+    int sz = len - write;
+    int ret;
+    char sztxt[16];
+    AppendHumanBytes(files.at(i)->fd.GetFileSize(), sztxt, 16);
+    ret = snprintf(output + write, sz, "%" PRIu64 "(%s) ",
+                   files.at(i)->fd.GetNumber(), sztxt);
+    if (ret < 0 || ret >= sz) break;
+    write += ret;
+  }
+  // if files.size() is non-zero, overwrite the last space
+  return write - !!files.size();
+}
+}  // namespace
+
+void Compaction::Summary(char* output, int len) {
+  int write =
+      snprintf(output, len, "Base version %" PRIu64
+                            " Base level %d, seek compaction:%d, inputs: [",
+               input_version_->GetVersionNumber(), level_, seek_compaction_);
+  if (write < 0 || write >= len) {
+    return;
+  }
+
+  write += InputSummary(inputs_[0], output + write, len - write);
+  if (write < 0 || write >= len) {
+    return;
+  }
+
+  write += snprintf(output + write, len - write, "], [");
+  if (write < 0 || write >= len) {
+    return;
+  }
+
+  write += InputSummary(inputs_[1], output + write, len - write);
+  if (write < 0 || write >= len) {
+    return;
+  }
+
+  snprintf(output + write, len - write, "]");
+}
+
+uint64_t Compaction::OutputFilePreallocationSize() {
+  uint64_t preallocation_size = 0;
+
+  if (cfd_->options()->compaction_style == kCompactionStyleLevel) {
+    preallocation_size =
+        cfd_->compaction_picker()->MaxFileSizeForLevel(output_level());
+  } else {
+    for (const auto& f : inputs_[0]) {
+      preallocation_size += f->fd.GetFileSize();
+    }
+  }
+  // Over-estimate slightly so we don't end up just barely crossing
+  // the threshold
+  return preallocation_size * 1.1;
+}
+
+}  // namespace rocksdb

db/compaction.h

@@ -0,0 +1,167 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#pragma once
+#include "db/version_set.h"
+
+namespace rocksdb {
+
+class Version;
+class ColumnFamilyData;
+
+// A Compaction encapsulates information about a compaction.
+class Compaction {
+ public:
+  ~Compaction();
+
+  // Return the level that is being compacted.  Inputs from "level"
+  // will be merged.
+  int level() const { return level_; }
+
+  // Outputs will go to this level
+  int output_level() const { return out_level_; }
+
+  // Return the object that holds the edits to the descriptor done
+  // by this compaction.
+  VersionEdit* edit() { return edit_; }
+
+  // "which" must be either 0 or 1
+  int num_input_files(int which) const { return inputs_[which].size(); }
+
+  // Returns input version of the compaction
+  Version* input_version() const { return input_version_; }
+
+  ColumnFamilyData* column_family_data() const { return cfd_; }
+
+  // Return the ith input file at "level()+which" ("which" must be 0 or 1).
+  FileMetaData* input(int which, int i) const { return inputs_[which][i]; }
+
+  std::vector<FileMetaData*>* inputs(int which) { return &inputs_[which]; }
+
+  // Maximum size of files to build during this compaction.
+  uint64_t MaxOutputFileSize() const { return max_output_file_size_; }
+
+  // What compression for output
+  CompressionType OutputCompressionType() const { return output_compression_; }
+
+  // Whether need to write output file to second DB path.
+  uint32_t GetOutputPathId() const { return output_path_id_; }
+
+    // Is this a trivial compaction that can be implemented by just
+  // moving a single input file to the next level (no merging or splitting)
+  bool IsTrivialMove() const;
+
+  // If true, just delete all files in inputs_[0]
+  bool IsDeletionCompaction() const;
+
+  // Add all inputs to this compaction as delete operations to *edit.
+  void AddInputDeletions(VersionEdit* edit);
+
+  // Returns true if the information we have available guarantees that
+  // the compaction is producing data in "level+1" for which no data exists
+  // in levels greater than "level+1".
+  bool IsBaseLevelForKey(const Slice& user_key);
+
+  // Returns true iff we should stop building the current output
+  // before processing "internal_key".
+  bool ShouldStopBefore(const Slice& internal_key);
+
+  // Release the input version for the compaction, once the compaction
+  // is successful.
+  void ReleaseInputs();
+
+  // Clear all files to indicate that they are not being compacted
+  // Delete this compaction from the list of running compactions.
+  void ReleaseCompactionFiles(Status status);
+
+  void Summary(char* output, int len);
+
+  // Return the score that was used to pick this compaction run.
+  double score() const { return score_; }
+
+  // Is this compaction creating a file in the bottom most level?
+  bool BottomMostLevel() { return bottommost_level_; }
+
+  // Does this compaction include all sst files?
+  bool IsFullCompaction() { return is_full_compaction_; }
+
+  // Was this compaction triggered manually by the client?
+  bool IsManualCompaction() { return is_manual_compaction_; }
+
+  // Returns a number of byte that the output file should be preallocated to
+  // In level compaction, that is max_file_size_. In universal compaction, that
+  // is the sum of all input file sizes
+  uint64_t OutputFilePreallocationSize();
+
+ private:
+  friend class CompactionPicker;
+  friend class UniversalCompactionPicker;
+  friend class FIFOCompactionPicker;
+  friend class LevelCompactionPicker;
+
+  Compaction(Version* input_version, int level, int out_level,
+             uint64_t target_file_size, uint64_t max_grandparent_overlap_bytes,
+             uint32_t output_path_id, CompressionType output_compression,
+             bool seek_compaction = false, bool deletion_compaction = false);
+
+  int level_;
+  int out_level_; // levels to which output files are stored
+  uint64_t max_output_file_size_;
+  uint64_t max_grandparent_overlap_bytes_;
+  Version* input_version_;
+  VersionEdit* edit_;
+  int number_levels_;
+  ColumnFamilyData* cfd_;
+
+  uint32_t output_path_id_;
+  CompressionType output_compression_;
+  bool seek_compaction_;
+  // if true, just delete files in inputs_[0]
+  bool deletion_compaction_;
+
+  // Each compaction reads inputs from "level_" and "level_+1"
+  std::vector<FileMetaData*> inputs_[2];      // The two sets of inputs
+
+  // State used to check for number of of overlapping grandparent files
+  // (parent == level_ + 1, grandparent == level_ + 2)
+  std::vector<FileMetaData*> grandparents_;
+  size_t grandparent_index_;  // Index in grandparent_starts_
+  bool seen_key_;             // Some output key has been seen
+  uint64_t overlapped_bytes_;  // Bytes of overlap between current output
+                              // and grandparent files
+  int base_index_;   // index of the file in files_[level_]
+  int parent_index_; // index of some file with same range in files_[level_+1]
+  double score_;     // score that was used to pick this compaction.
+
+  // Is this compaction creating a file in the bottom most level?
+  bool bottommost_level_;
+  // Does this compaction include all sst files?
+  bool is_full_compaction_;
+
+  // Is this compaction requested by the client?
+  bool is_manual_compaction_;
+
+  // level_ptrs_ holds indices into input_version_->levels_: our state
+  // is that we are positioned at one of the file ranges for each
+  // higher level than the ones involved in this compaction (i.e. for
+  // all L >= level_ + 2).
+  std::vector<size_t> level_ptrs_;
+
+  // mark (or clear) all files that are being compacted
+  void MarkFilesBeingCompacted(bool);
+
+  // Initialize whether compaction producing files at the bottommost level
+  void SetupBottomMostLevel(bool isManual);
+
+  // In case of compaction error, reset the nextIndex that is used
+  // to pick up the next file to be compacted from files_by_size_
+  void ResetNextCompactionIndex();
+};
+
+}  // namespace rocksdb

db/compaction_picker.cc

@@ -0,0 +1,953 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "db/compaction_picker.h"
+
+#define __STDC_FORMAT_MACROS
+#include <inttypes.h>
+#include <limits>
+#include "db/filename.h"
+#include "util/log_buffer.h"
+#include "util/statistics.h"
+
+namespace rocksdb {
+
+namespace {
+// Determine compression type, based on user options, level of the output
+// file and whether compression is disabled.
+// If enable_compression is false, then compression is always disabled no
+// matter what the values of the other two parameters are.
+// Otherwise, the compression type is determined based on options and level.
+CompressionType GetCompressionType(const Options& options, int level,
+                                   const bool enable_compression = true) {
+  if (!enable_compression) {
+    // disable compression
+    return kNoCompression;
+  }
+  // If the use has specified a different compression level for each level,
+  // then pick the compresison for that level.
+  if (!options.compression_per_level.empty()) {
+    const int n = options.compression_per_level.size() - 1;
+    // It is possible for level_ to be -1; in that case, we use level
+    // 0's compression.  This occurs mostly in backwards compatibility
+    // situations when the builder doesn't know what level the file
+    // belongs to.  Likewise, if level_ is beyond the end of the
+    // specified compression levels, use the last value.
+    return options.compression_per_level[std::max(0, std::min(level, n))];
+  } else {
+    return options.compression;
+  }
+}
+
+uint64_t TotalCompensatedFileSize(const std::vector<FileMetaData*>& files) {
+  uint64_t sum = 0;
+  for (size_t i = 0; i < files.size() && files[i]; i++) {
+    sum += files[i]->compensated_file_size;
+  }
+  return sum;
+}
+
+// Multiple two operands. If they overflow, return op1.
+uint64_t MultiplyCheckOverflow(uint64_t op1, int op2) {
+  if (op1 == 0) {
+    return 0;
+  }
+  if (op2 <= 0) {
+    return op1;
+  }
+  uint64_t casted_op2 = (uint64_t) op2;
+  if (std::numeric_limits<uint64_t>::max() / op1 < casted_op2) {
+    return op1;
+  }
+  return op1 * casted_op2;
+}
+
+}  // anonymous namespace
+
+CompactionPicker::CompactionPicker(const Options* options,
+                                   const InternalKeyComparator* icmp)
+    : compactions_in_progress_(options->num_levels),
+      options_(options),
+      num_levels_(options->num_levels),
+      icmp_(icmp) {
+
+  max_file_size_.reset(new uint64_t[NumberLevels()]);
+  level_max_bytes_.reset(new uint64_t[NumberLevels()]);
+  int target_file_size_multiplier = options_->target_file_size_multiplier;
+  int max_bytes_multiplier = options_->max_bytes_for_level_multiplier;
+  for (int i = 0; i < NumberLevels(); i++) {
+    if (i == 0 && options_->compaction_style == kCompactionStyleUniversal) {
+      max_file_size_[i] = ULLONG_MAX;
+      level_max_bytes_[i] = options_->max_bytes_for_level_base;
+    } else if (i > 1) {
+      max_file_size_[i] = MultiplyCheckOverflow(max_file_size_[i - 1],
+                                                target_file_size_multiplier);
+      level_max_bytes_[i] = MultiplyCheckOverflow(
+          MultiplyCheckOverflow(level_max_bytes_[i - 1], max_bytes_multiplier),
+          options_->max_bytes_for_level_multiplier_additional[i - 1]);
+    } else {
+      max_file_size_[i] = options_->target_file_size_base;
+      level_max_bytes_[i] = options_->max_bytes_for_level_base;
+    }
+  }
+}
+
+CompactionPicker::~CompactionPicker() {}
+
+void CompactionPicker::SizeBeingCompacted(std::vector<uint64_t>& sizes) {
+  for (int level = 0; level < NumberLevels() - 1; level++) {
+    uint64_t total = 0;
+    for (auto c : compactions_in_progress_[level]) {
+      assert(c->level() == level);
+      for (int i = 0; i < c->num_input_files(0); i++) {
+        total += c->input(0, i)->compensated_file_size;
+      }
+    }
+    sizes[level] = total;
+  }
+}
+
+// Clear all files to indicate that they are not being compacted
+// Delete this compaction from the list of running compactions.
+void CompactionPicker::ReleaseCompactionFiles(Compaction* c, Status status) {
+  c->MarkFilesBeingCompacted(false);
+  compactions_in_progress_[c->level()].erase(c);
+  if (!status.ok()) {
+    c->ResetNextCompactionIndex();
+  }
+}
+
+uint64_t CompactionPicker::MaxFileSizeForLevel(int level) const {
+  assert(level >= 0);
+  assert(level < NumberLevels());
+  return max_file_size_[level];
+}
+
+uint64_t CompactionPicker::MaxGrandParentOverlapBytes(int level) {
+  uint64_t result = MaxFileSizeForLevel(level);
+  result *= options_->max_grandparent_overlap_factor;
+  return result;
+}
+
+double CompactionPicker::MaxBytesForLevel(int level) {
+  // Note: the result for level zero is not really used since we set
+  // the level-0 compaction threshold based on number of files.
+  assert(level >= 0);
+  assert(level < NumberLevels());
+  return level_max_bytes_[level];
+}
+
+void CompactionPicker::GetRange(const std::vector<FileMetaData*>& inputs,
+                                InternalKey* smallest, InternalKey* largest) {
+  assert(!inputs.empty());
+  smallest->Clear();
+  largest->Clear();
+  for (size_t i = 0; i < inputs.size(); i++) {
+    FileMetaData* f = inputs[i];
+    if (i == 0) {
+      *smallest = f->smallest;
+      *largest = f->largest;
+    } else {
+      if (icmp_->Compare(f->smallest, *smallest) < 0) {
+        *smallest = f->smallest;
+      }
+      if (icmp_->Compare(f->largest, *largest) > 0) {
+        *largest = f->largest;
+      }
+    }
+  }
+}
+
+void CompactionPicker::GetRange(const std::vector<FileMetaData*>& inputs1,
+                                const std::vector<FileMetaData*>& inputs2,
+                                InternalKey* smallest, InternalKey* largest) {
+  std::vector<FileMetaData*> all = inputs1;
+  all.insert(all.end(), inputs2.begin(), inputs2.end());
+  GetRange(all, smallest, largest);
+}
+
+bool CompactionPicker::ExpandWhileOverlapping(Compaction* c) {
+  // If inputs are empty then there is nothing to expand.
+  if (!c || c->inputs_[0].empty()) {
+    return true;
+  }
+
+  // GetOverlappingInputs will always do the right thing for level-0.
+  // So we don't need to do any expansion if level == 0.
+  if (c->level() == 0) {
+    return true;
+  }
+
+  const int level = c->level();
+  InternalKey smallest, largest;
+
+  // Keep expanding c->inputs_[0] until we are sure that there is a
+  // "clean cut" boundary between the files in input and the surrounding files.
+  // This will ensure that no parts of a key are lost during compaction.
+  int hint_index = -1;
+  size_t old_size;
+  do {
+    old_size = c->inputs_[0].size();
+    GetRange(c->inputs_[0], &smallest, &largest);
+    c->inputs_[0].clear();
+    c->input_version_->GetOverlappingInputs(
+        level, &smallest, &largest, &c->inputs_[0], hint_index, &hint_index);
+  } while(c->inputs_[0].size() > old_size);
+
+  // Get the new range
+  GetRange(c->inputs_[0], &smallest, &largest);
+
+  // If, after the expansion, there are files that are already under
+  // compaction, then we must drop/cancel this compaction.
+  int parent_index = -1;
+  if (c->inputs_[0].empty()) {
+    Log(options_->info_log,
+        "[%s] ExpandWhileOverlapping() failure because zero input files",
+        c->column_family_data()->GetName().c_str());
+  }
+  if (c->inputs_[0].empty() || FilesInCompaction(c->inputs_[0]) ||
+      (c->level() != c->output_level() &&
+       ParentRangeInCompaction(c->input_version_, &smallest, &largest, level,
+                               &parent_index))) {
+    c->inputs_[0].clear();
+    c->inputs_[1].clear();
+    return false;
+  }
+  return true;
+}
+
+uint64_t CompactionPicker::ExpandedCompactionByteSizeLimit(int level) {
+  uint64_t result = MaxFileSizeForLevel(level);
+  result *= options_->expanded_compaction_factor;
+  return result;
+}
+
+// Returns true if any one of specified files are being compacted
+bool CompactionPicker::FilesInCompaction(std::vector<FileMetaData*>& files) {
+  for (unsigned int i = 0; i < files.size(); i++) {
+    if (files[i]->being_compacted) {
+      return true;
+    }
+  }
+  return false;
+}
+
+// Returns true if any one of the parent files are being compacted
+bool CompactionPicker::ParentRangeInCompaction(Version* version,
+                                               const InternalKey* smallest,
+                                               const InternalKey* largest,
+                                               int level, int* parent_index) {
+  std::vector<FileMetaData*> inputs;
+  assert(level + 1 < NumberLevels());
+
+  version->GetOverlappingInputs(level + 1, smallest, largest, &inputs,
+                                *parent_index, parent_index);
+  return FilesInCompaction(inputs);
+}
+
+// Populates the set of inputs from "level+1" that overlap with "level".
+// Will also attempt to expand "level" if that doesn't expand "level+1"
+// or cause "level" to include a file for compaction that has an overlapping
+// user-key with another file.
+void CompactionPicker::SetupOtherInputs(Compaction* c) {
+  // If inputs are empty, then there is nothing to expand.
+  // If both input and output levels are the same, no need to consider
+  // files at level "level+1"
+  if (c->inputs_[0].empty() || c->level() == c->output_level()) {
+    return;
+  }
+
+  const int level = c->level();
+  InternalKey smallest, largest;
+
+  // Get the range one last time.
+  GetRange(c->inputs_[0], &smallest, &largest);
+
+  // Populate the set of next-level files (inputs_[1]) to include in compaction
+  c->input_version_->GetOverlappingInputs(level + 1, &smallest, &largest,
+                                          &c->inputs_[1], c->parent_index_,
+                                          &c->parent_index_);
+
+  // Get entire range covered by compaction
+  InternalKey all_start, all_limit;
+  GetRange(c->inputs_[0], c->inputs_[1], &all_start, &all_limit);
+
+  // See if we can further grow the number of inputs in "level" without
+  // changing the number of "level+1" files we pick up. We also choose NOT
+  // to expand if this would cause "level" to include some entries for some
+  // user key, while excluding other entries for the same user key. This
+  // can happen when one user key spans multiple files.
+  if (!c->inputs_[1].empty()) {
+    std::vector<FileMetaData*> expanded0;
+    c->input_version_->GetOverlappingInputs(
+        level, &all_start, &all_limit, &expanded0, c->base_index_, nullptr);
+    const uint64_t inputs0_size = TotalCompensatedFileSize(c->inputs_[0]);
+    const uint64_t inputs1_size = TotalCompensatedFileSize(c->inputs_[1]);
+    const uint64_t expanded0_size = TotalCompensatedFileSize(expanded0);
+    uint64_t limit = ExpandedCompactionByteSizeLimit(level);
+    if (expanded0.size() > c->inputs_[0].size() &&
+        inputs1_size + expanded0_size < limit &&
+        !FilesInCompaction(expanded0) &&
+        !c->input_version_->HasOverlappingUserKey(&expanded0, level)) {
+      InternalKey new_start, new_limit;
+      GetRange(expanded0, &new_start, &new_limit);
+      std::vector<FileMetaData*> expanded1;
+      c->input_version_->GetOverlappingInputs(level + 1, &new_start, &new_limit,
+                                              &expanded1, c->parent_index_,
+                                              &c->parent_index_);
+      if (expanded1.size() == c->inputs_[1].size() &&
+          !FilesInCompaction(expanded1)) {
+        Log(options_->info_log,
+            "[%s] Expanding@%d %zu+%zu (%" PRIu64 "+%" PRIu64
+            " bytes) to %zu+%zu (%" PRIu64 "+%" PRIu64 "bytes)\n",
+            c->column_family_data()->GetName().c_str(), level,
+            c->inputs_[0].size(), c->inputs_[1].size(), inputs0_size,
+            inputs1_size, expanded0.size(), expanded1.size(), expanded0_size,
+            inputs1_size);
+        smallest = new_start;
+        largest = new_limit;
+        c->inputs_[0] = expanded0;
+        c->inputs_[1] = expanded1;
+        GetRange(c->inputs_[0], c->inputs_[1], &all_start, &all_limit);
+      }
+    }
+  }
+
+  // Compute the set of grandparent files that overlap this compaction
+  // (parent == level+1; grandparent == level+2)
+  if (level + 2 < NumberLevels()) {
+    c->input_version_->GetOverlappingInputs(level + 2, &all_start, &all_limit,
+                                            &c->grandparents_);
+  }
+}
+
+
+Compaction* CompactionPicker::CompactRange(Version* version, int input_level,
+                                           int output_level,
+                                           const InternalKey* begin,
+                                           const InternalKey* end,
+                                           InternalKey** compaction_end) {
+  // CompactionPickerFIFO has its own implementation of compact range
+  assert(options_->compaction_style != kCompactionStyleFIFO);
+
+  std::vector<FileMetaData*> inputs;
+  bool covering_the_whole_range = true;
+
+  // All files are 'overlapping' in universal style compaction.
+  // We have to compact the entire range in one shot.
+  if (options_->compaction_style == kCompactionStyleUniversal) {
+    begin = nullptr;
+    end = nullptr;
+  }
+  version->GetOverlappingInputs(input_level, begin, end, &inputs);
+  if (inputs.empty()) {
+    return nullptr;
+  }
+
+  // Avoid compacting too much in one shot in case the range is large.
+  // But we cannot do this for level-0 since level-0 files can overlap
+  // and we must not pick one file and drop another older file if the
+  // two files overlap.
+  if (input_level > 0) {
+    const uint64_t limit =
+        MaxFileSizeForLevel(input_level) * options_->source_compaction_factor;
+    uint64_t total = 0;
+    for (size_t i = 0; i + 1 < inputs.size(); ++i) {
+      uint64_t s = inputs[i]->compensated_file_size;
+      total += s;
+      if (total >= limit) {
+        **compaction_end = inputs[i + 1]->smallest;
+        covering_the_whole_range = false;
+        inputs.resize(i + 1);
+        break;
+      }
+    }
+  }
+  Compaction* c = new Compaction(version, input_level, output_level,
+                                 MaxFileSizeForLevel(output_level),
+                                 MaxGrandParentOverlapBytes(input_level), 0,
+                                 GetCompressionType(*options_, output_level));
+
+  c->inputs_[0] = inputs;
+  if (ExpandWhileOverlapping(c) == false) {
+    delete c;
+    Log(options_->info_log,
+        "[%s] Could not compact due to expansion failure.\n",
+        version->cfd_->GetName().c_str());
+    return nullptr;
+  }
+
+  SetupOtherInputs(c);
+
+  if (covering_the_whole_range) {
+    *compaction_end = nullptr;
+  }
+
+  // These files that are to be manaully compacted do not trample
+  // upon other files because manual compactions are processed when
+  // the system has a max of 1 background compaction thread.
+  c->MarkFilesBeingCompacted(true);
+
+  // Is this compaction creating a file at the bottommost level
+  c->SetupBottomMostLevel(true);
+
+  c->is_manual_compaction_ = true;
+
+  return c;
+}
+
+Compaction* LevelCompactionPicker::PickCompaction(Version* version,
+                                                  LogBuffer* log_buffer) {
+  Compaction* c = nullptr;
+  int level = -1;
+
+  // Compute the compactions needed. It is better to do it here
+  // and also in LogAndApply(), otherwise the values could be stale.
+  std::vector<uint64_t> size_being_compacted(NumberLevels() - 1);
+  SizeBeingCompacted(size_being_compacted);
+  version->ComputeCompactionScore(size_being_compacted);
+
+  // We prefer compactions triggered by too much data in a level over
+  // the compactions triggered by seeks.
+  //
+  // Find the compactions by size on all levels.
+  for (int i = 0; i < NumberLevels() - 1; i++) {
+    assert(i == 0 ||
+           version->compaction_score_[i] <= version->compaction_score_[i - 1]);
+    level = version->compaction_level_[i];
+    if ((version->compaction_score_[i] >= 1)) {
+      c = PickCompactionBySize(version, level, version->compaction_score_[i]);
+      if (ExpandWhileOverlapping(c) == false) {
+        delete c;
+        c = nullptr;
+      } else {
+        break;
+      }
+    }
+  }
+
+  if (c == nullptr) {
+    return nullptr;
+  }
+
+  // Two level 0 compaction won't run at the same time, so don't need to worry
+  // about files on level 0 being compacted.
+  if (level == 0) {
+    assert(compactions_in_progress_[0].empty());
+    InternalKey smallest, largest;
+    GetRange(c->inputs_[0], &smallest, &largest);
+    // Note that the next call will discard the file we placed in
+    // c->inputs_[0] earlier and replace it with an overlapping set
+    // which will include the picked file.
+    c->inputs_[0].clear();
+    c->input_version_->GetOverlappingInputs(0, &smallest, &largest,
+                                            &c->inputs_[0]);
+
+    // If we include more L0 files in the same compaction run it can
+    // cause the 'smallest' and 'largest' key to get extended to a
+    // larger range. So, re-invoke GetRange to get the new key range
+    GetRange(c->inputs_[0], &smallest, &largest);
+    if (ParentRangeInCompaction(c->input_version_, &smallest, &largest, level,
+                                &c->parent_index_)) {
+      delete c;
+      return nullptr;
+    }
+    assert(!c->inputs_[0].empty());
+  }
+
+  // Setup "level+1" files (inputs_[1])
+  SetupOtherInputs(c);
+
+  // mark all the files that are being compacted
+  c->MarkFilesBeingCompacted(true);
+
+  // Is this compaction creating a file at the bottommost level
+  c->SetupBottomMostLevel(false);
+
+  // remember this currently undergoing compaction
+  compactions_in_progress_[level].insert(c);
+
+  return c;
+}
+
+Compaction* LevelCompactionPicker::PickCompactionBySize(Version* version,
+                                                        int level,
+                                                        double score) {
+  Compaction* c = nullptr;
+
+  // level 0 files are overlapping. So we cannot pick more
+  // than one concurrent compactions at this level. This
+  // could be made better by looking at key-ranges that are
+  // being compacted at level 0.
+  if (level == 0 && compactions_in_progress_[level].size() == 1) {
+    return nullptr;
+  }
+
+  assert(level >= 0);
+  assert(level + 1 < NumberLevels());
+  c = new Compaction(version, level, level + 1, MaxFileSizeForLevel(level + 1),
+                     MaxGrandParentOverlapBytes(level), 0,
+                     GetCompressionType(*options_, level + 1));
+  c->score_ = score;
+
+  // Pick the largest file in this level that is not already
+  // being compacted
+  std::vector<int>& file_size = c->input_version_->files_by_size_[level];
+
+  // record the first file that is not yet compacted
+  int nextIndex = -1;
+
+  for (unsigned int i = c->input_version_->next_file_to_compact_by_size_[level];
+       i < file_size.size(); i++) {
+    int index = file_size[i];
+    FileMetaData* f = c->input_version_->files_[level][index];
+
+    // Check to verify files are arranged in descending compensated size.
+    assert((i == file_size.size() - 1) ||
+           (i >= Version::number_of_files_to_sort_ - 1) ||
+           (f->compensated_file_size >=
+            c->input_version_->files_[level][file_size[i + 1]]->
+                compensated_file_size));
+
+    // do not pick a file to compact if it is being compacted
+    // from n-1 level.
+    if (f->being_compacted) {
+      continue;
+    }
+
+    // remember the startIndex for the next call to PickCompaction
+    if (nextIndex == -1) {
+      nextIndex = i;
+    }
+
+    // Do not pick this file if its parents at level+1 are being compacted.
+    // Maybe we can avoid redoing this work in SetupOtherInputs
+    int parent_index = -1;
+    if (ParentRangeInCompaction(c->input_version_, &f->smallest, &f->largest,
+                                level, &parent_index)) {
+      continue;
+    }
+    c->inputs_[0].push_back(f);
+    c->base_index_ = index;
+    c->parent_index_ = parent_index;
+    break;
+  }
+
+  if (c->inputs_[0].empty()) {
+    delete c;
+    c = nullptr;
+  }
+
+  // store where to start the iteration in the next call to PickCompaction
+  version->next_file_to_compact_by_size_[level] = nextIndex;
+
+  return c;
+}
+
+// Universal style of compaction. Pick files that are contiguous in
+// time-range to compact.
+//
+Compaction* UniversalCompactionPicker::PickCompaction(Version* version,
+                                                      LogBuffer* log_buffer) {
+  int level = 0;
+  double score = version->compaction_score_[0];
+
+  if ((version->files_[level].size() <
+       (unsigned int)options_->level0_file_num_compaction_trigger)) {
+    LogToBuffer(log_buffer, "[%s] Universal: nothing to do\n",
+                version->cfd_->GetName().c_str());
+    return nullptr;
+  }
+  Version::FileSummaryStorage tmp;
+  LogToBuffer(log_buffer, "[%s] Universal: candidate files(%zu): %s\n",
+              version->cfd_->GetName().c_str(), version->files_[level].size(),
+              version->LevelFileSummary(&tmp, 0));
+
+  // Check for size amplification first.
+  Compaction* c;
+  if ((c = PickCompactionUniversalSizeAmp(version, score, log_buffer)) !=
+      nullptr) {
+    LogToBuffer(log_buffer, "[%s] Universal: compacting for size amp\n",
+                version->cfd_->GetName().c_str());
+  } else {
+    // Size amplification is within limits. Try reducing read
+    // amplification while maintaining file size ratios.
+    unsigned int ratio = options_->compaction_options_universal.size_ratio;
+
+    if ((c = PickCompactionUniversalReadAmp(version, score, ratio, UINT_MAX,
+                                            log_buffer)) != nullptr) {
+      LogToBuffer(log_buffer, "[%s] Universal: compacting for size ratio\n",
+                  version->cfd_->GetName().c_str());
+    } else {
+      // Size amplification and file size ratios are within configured limits.
+      // If max read amplification is exceeding configured limits, then force
+      // compaction without looking at filesize ratios and try to reduce
+      // the number of files to fewer than level0_file_num_compaction_trigger.
+      unsigned int num_files = version->files_[level].size() -
+                               options_->level0_file_num_compaction_trigger;
+      if ((c = PickCompactionUniversalReadAmp(
+               version, score, UINT_MAX, num_files, log_buffer)) != nullptr) {
+        LogToBuffer(log_buffer, "[%s] Universal: compacting for file num\n",
+                    version->cfd_->GetName().c_str());
+      }
+    }
+  }
+  if (c == nullptr) {
+    return nullptr;
+  }
+  assert(c->inputs_[0].size() > 1);
+
+  // validate that all the chosen files are non overlapping in time
+  FileMetaData* newerfile __attribute__((unused)) = nullptr;
+  for (unsigned int i = 0; i < c->inputs_[0].size(); i++) {
+    FileMetaData* f = c->inputs_[0][i];
+    assert (f->smallest_seqno <= f->largest_seqno);
+    assert(newerfile == nullptr ||
+           newerfile->smallest_seqno > f->largest_seqno);
+    newerfile = f;
+  }
+
+  // Is the earliest file part of this compaction?
+  FileMetaData* last_file = c->input_version_->files_[level].back();
+  c->bottommost_level_ = c->inputs_[0].back() == last_file;
+
+  // update statistics
+  MeasureTime(options_->statistics.get(), NUM_FILES_IN_SINGLE_COMPACTION,
+              c->inputs_[0].size());
+
+  // mark all the files that are being compacted
+  c->MarkFilesBeingCompacted(true);
+
+  // remember this currently undergoing compaction
+  compactions_in_progress_[level].insert(c);
+
+  // Record whether this compaction includes all sst files.
+  // For now, it is only relevant in universal compaction mode.
+  c->is_full_compaction_ =
+      (c->inputs_[0].size() == c->input_version_->files_[0].size());
+
+  return c;
+}
+
+//
+// Consider compaction files based on their size differences with
+// the next file in time order.
+//
+Compaction* UniversalCompactionPicker::PickCompactionUniversalReadAmp(
+    Version* version, double score, unsigned int ratio,
+    unsigned int max_number_of_files_to_compact, LogBuffer* log_buffer) {
+  int level = 0;
+
+  unsigned int min_merge_width =
+    options_->compaction_options_universal.min_merge_width;
+  unsigned int max_merge_width =
+    options_->compaction_options_universal.max_merge_width;
+
+  // The files are sorted from newest first to oldest last.
+  const auto& files = version->files_[level];
+
+  FileMetaData* f = nullptr;
+  bool done = false;
+  int start_index = 0;
+  unsigned int candidate_count = 0;
+
+  unsigned int max_files_to_compact = std::min(max_merge_width,
+                                       max_number_of_files_to_compact);
+  min_merge_width = std::max(min_merge_width, 2U);
+
+  // Considers a candidate file only if it is smaller than the
+  // total size accumulated so far.
+  for (unsigned int loop = 0; loop < files.size(); loop++) {
+
+    candidate_count = 0;
+
+    // Skip files that are already being compacted
+    for (f = nullptr; loop < files.size(); loop++) {
+      f = files[loop];
+
+      if (!f->being_compacted) {
+        candidate_count = 1;
+        break;
+      }
+      LogToBuffer(log_buffer, "[%s] Universal: file %" PRIu64
+                              "[%d] being compacted, skipping",
+                  version->cfd_->GetName().c_str(), f->fd.GetNumber(), loop);
+      f = nullptr;
+    }
+
+    // This file is not being compacted. Consider it as the
+    // first candidate to be compacted.
+    uint64_t candidate_size =  f != nullptr? f->compensated_file_size : 0;
+    if (f != nullptr) {
+      LogToBuffer(
+          log_buffer, "[%s] Universal: Possible candidate file %s[%d].",
+          version->cfd_->GetName().c_str(),
+          FormatFileNumber(f->fd.GetNumber(), f->fd.GetPathId()).c_str(), loop);
+    }
+
+    // Check if the suceeding files need compaction.
+    for (unsigned int i = loop + 1;
+         candidate_count < max_files_to_compact && i < files.size(); i++) {
+      FileMetaData* f = files[i];
+      if (f->being_compacted) {
+        break;
+      }
+      // Pick files if the total/last candidate file size (increased by the
+      // specified ratio) is still larger than the next candidate file.
+      // candidate_size is the total size of files picked so far with the
+      // default kCompactionStopStyleTotalSize; with
+      // kCompactionStopStyleSimilarSize, it's simply the size of the last
+      // picked file.
+      uint64_t sz = (candidate_size * (100L + ratio)) /100;
+      if (sz < f->fd.GetFileSize()) {
+        break;
+      }
+      if (options_->compaction_options_universal.stop_style == kCompactionStopStyleSimilarSize) {
+        // Similar-size stopping rule: also check the last picked file isn't
+        // far larger than the next candidate file.
+        sz = (f->fd.GetFileSize() * (100L + ratio)) / 100;
+        if (sz < candidate_size) {
+          // If the small file we've encountered begins a run of similar-size
+          // files, we'll pick them up on a future iteration of the outer
+          // loop. If it's some lonely straggler, it'll eventually get picked
+          // by the last-resort read amp strategy which disregards size ratios.
+          break;
+        }
+        candidate_size = f->compensated_file_size;
+      } else { // default kCompactionStopStyleTotalSize
+        candidate_size += f->compensated_file_size;
+      }
+      candidate_count++;
+    }
+
+    // Found a series of consecutive files that need compaction.
+    if (candidate_count >= (unsigned int)min_merge_width) {
+      start_index = loop;
+      done = true;
+      break;
+    } else {
+      for (unsigned int i = loop;
+           i < loop + candidate_count && i < files.size(); i++) {
+        FileMetaData* f = files[i];
+        LogToBuffer(log_buffer, "[%s] Universal: Skipping file %" PRIu64
+                                "[%d] with size %" PRIu64
+                                " (compensated size %" PRIu64 ") %d\n",
+                    version->cfd_->GetName().c_str(), f->fd.GetNumber(), i,
+                    f->fd.GetFileSize(), f->compensated_file_size,
+                    f->being_compacted);
+      }
+    }
+  }
+  if (!done || candidate_count <= 1) {
+    return nullptr;
+  }
+  unsigned int first_index_after = start_index + candidate_count;
+  // Compression is enabled if files compacted earlier already reached
+  // size ratio of compression.
+  bool enable_compression = true;
+  int ratio_to_compress =
+      options_->compaction_options_universal.compression_size_percent;
+  if (ratio_to_compress >= 0) {
+    uint64_t total_size = version->NumLevelBytes(level);
+    uint64_t older_file_size = 0;
+    for (unsigned int i = files.size() - 1;
+         i >= first_index_after; i--) {
+      older_file_size += files[i]->fd.GetFileSize();
+      if (older_file_size * 100L >= total_size * (long) ratio_to_compress) {
+        enable_compression = false;
+        break;
+      }
+    }
+  }
+  Compaction* c = new Compaction(
+      version, level, level, MaxFileSizeForLevel(level), LLONG_MAX, 0,
+      GetCompressionType(*options_, level, enable_compression));
+  c->score_ = score;
+
+  for (unsigned int i = start_index; i < first_index_after; i++) {
+    FileMetaData* f = c->input_version_->files_[level][i];
+    c->inputs_[0].push_back(f);
+    LogToBuffer(log_buffer,
+                "[%s] Universal: Picking file %s[%d] "
+                "with size %" PRIu64 " (compensated size %" PRIu64 ")\n",
+                version->cfd_->GetName().c_str(),
+                FormatFileNumber(f->fd.GetNumber(), f->fd.GetPathId()).c_str(),
+                i, f->fd.GetFileSize(), f->compensated_file_size);
+  }
+  return c;
+}
+
+// Look at overall size amplification. If size amplification
+// exceeeds the configured value, then do a compaction
+// of the candidate files all the way upto the earliest
+// base file (overrides configured values of file-size ratios,
+// min_merge_width and max_merge_width).
+//
+Compaction* UniversalCompactionPicker::PickCompactionUniversalSizeAmp(
+    Version* version, double score, LogBuffer* log_buffer) {
+  int level = 0;
+
+  // percentage flexibilty while reducing size amplification
+  uint64_t ratio = options_->compaction_options_universal.
+                     max_size_amplification_percent;
+
+  // The files are sorted from newest first to oldest last.
+  const auto& files = version->files_[level];
+
+  unsigned int candidate_count = 0;
+  uint64_t candidate_size = 0;
+  unsigned int start_index = 0;
+  FileMetaData* f = nullptr;
+
+  // Skip files that are already being compacted
+  for (unsigned int loop = 0; loop < files.size() - 1; loop++) {
+    f = files[loop];
+    if (!f->being_compacted) {
+      start_index = loop;         // Consider this as the first candidate.
+      break;
+    }
+    LogToBuffer(log_buffer, "[%s] Universal: skipping file %s[%d] compacted %s",
+                version->cfd_->GetName().c_str(),
+                FormatFileNumber(f->fd.GetNumber(), f->fd.GetPathId()).c_str(),
+                loop, " cannot be a candidate to reduce size amp.\n");
+    f = nullptr;
+  }
+  if (f == nullptr) {
+    return nullptr;             // no candidate files
+  }
+
+  LogToBuffer(log_buffer, "[%s] Universal: First candidate file %s[%d] %s",
+              version->cfd_->GetName().c_str(),
+              FormatFileNumber(f->fd.GetNumber(), f->fd.GetPathId()).c_str(),
+              start_index, " to reduce size amp.\n");
+
+  // keep adding up all the remaining files
+  for (unsigned int loop = start_index; loop < files.size() - 1; loop++) {
+    f = files[loop];
+    if (f->being_compacted) {
+      LogToBuffer(
+          log_buffer, "[%s] Universal: Possible candidate file %s[%d] %s.",
+          version->cfd_->GetName().c_str(),
+          FormatFileNumber(f->fd.GetNumber(), f->fd.GetPathId()).c_str(), loop,
+          " is already being compacted. No size amp reduction possible.\n");
+      return nullptr;
+    }
+    candidate_size += f->compensated_file_size;
+    candidate_count++;
+  }
+  if (candidate_count == 0) {
+    return nullptr;
+  }
+
+  // size of earliest file
+  uint64_t earliest_file_size = files.back()->fd.GetFileSize();
+
+  // size amplification = percentage of additional size
+  if (candidate_size * 100 < ratio * earliest_file_size) {
+    LogToBuffer(
+        log_buffer,
+        "[%s] Universal: size amp not needed. newer-files-total-size %" PRIu64
+        "earliest-file-size %" PRIu64,
+        version->cfd_->GetName().c_str(), candidate_size, earliest_file_size);
+    return nullptr;
+  } else {
+    LogToBuffer(
+        log_buffer,
+        "[%s] Universal: size amp needed. newer-files-total-size %" PRIu64
+        "earliest-file-size %" PRIu64,
+        version->cfd_->GetName().c_str(), candidate_size, earliest_file_size);
+  }
+  assert(start_index >= 0 && start_index < files.size() - 1);
+
+  // create a compaction request
+  // We always compact all the files, so always compress.
+  Compaction* c =
+      new Compaction(version, level, level, MaxFileSizeForLevel(level),
+                     LLONG_MAX, 0, GetCompressionType(*options_, level));
+  c->score_ = score;
+  for (unsigned int loop = start_index; loop < files.size(); loop++) {
+    f = c->input_version_->files_[level][loop];
+    c->inputs_[0].push_back(f);
+    LogToBuffer(log_buffer,
+        "[%s] Universal: size amp picking file %" PRIu64 "[%d] "
+        "with size %" PRIu64 " (compensated size %" PRIu64 ")",
+        version->cfd_->GetName().c_str(),
+        f->fd.GetNumber(), loop,
+        f->fd.GetFileSize(), f->compensated_file_size);
+  }
+  return c;
+}
+
+Compaction* FIFOCompactionPicker::PickCompaction(Version* version,
+                                                 LogBuffer* log_buffer) {
+  assert(version->NumberLevels() == 1);
+  uint64_t total_size = 0;
+  for (const auto& file : version->files_[0]) {
+    total_size += file->compensated_file_size;
+  }
+
+  if (total_size <= options_->compaction_options_fifo.max_table_files_size ||
+      version->files_[0].size() == 0) {
+    // total size not exceeded
+    LogToBuffer(log_buffer,
+                "[%s] FIFO compaction: nothing to do. Total size %" PRIu64
+                ", max size %" PRIu64 "\n",
+                version->cfd_->GetName().c_str(), total_size,
+                options_->compaction_options_fifo.max_table_files_size);
+    return nullptr;
+  }
+
+  if (compactions_in_progress_[0].size() > 0) {
+    LogToBuffer(log_buffer,
+                "[%s] FIFO compaction: Already executing compaction. No need "
+                "to run parallel compactions since compactions are very fast",
+                version->cfd_->GetName().c_str());
+    return nullptr;
+  }
+
+  Compaction* c = new Compaction(version, 0, 0, 0, 0, 0, kNoCompression, false,
+                                 true /* is deletion compaction */);
+  // delete old files (FIFO)
+  for (auto ritr = version->files_[0].rbegin();
+       ritr != version->files_[0].rend(); ++ritr) {
+    auto f = *ritr;
+    total_size -= f->compensated_file_size;
+    c->inputs_[0].push_back(f);
+    char tmp_fsize[16];
+    AppendHumanBytes(f->fd.GetFileSize(), tmp_fsize, sizeof(tmp_fsize));
+    LogToBuffer(log_buffer, "[%s] FIFO compaction: picking file %" PRIu64
+                            " with size %s for deletion",
+                version->cfd_->GetName().c_str(), f->fd.GetNumber(), tmp_fsize);
+    if (total_size <= options_->compaction_options_fifo.max_table_files_size) {
+      break;
+    }
+  }
+
+  c->MarkFilesBeingCompacted(true);
+  compactions_in_progress_[0].insert(c);
+
+  return c;
+}
+
+Compaction* FIFOCompactionPicker::CompactRange(Version* version,
+                                               int input_level,
+                                               int output_level,
+                                               const InternalKey* begin,
+                                               const InternalKey* end,
+                                               InternalKey** compaction_end) {
+  assert(input_level == 0);
+  assert(output_level == 0);
+  *compaction_end = nullptr;
+  LogBuffer log_buffer(InfoLogLevel::INFO_LEVEL, options_->info_log.get());
+  auto c = PickCompaction(version, &log_buffer);
+  log_buffer.FlushBufferToLog();
+  return c;
+}
+
+}  // namespace rocksdb

db/compaction_picker.h

@@ -0,0 +1,181 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#pragma once
+#include "db/version_set.h"
+#include "db/compaction.h"
+#include "rocksdb/status.h"
+#include "rocksdb/options.h"
+#include "rocksdb/env.h"
+
+#include <vector>
+#include <memory>
+#include <set>
+
+namespace rocksdb {
+
+class LogBuffer;
+class Compaction;
+class Version;
+
+class CompactionPicker {
+ public:
+  CompactionPicker(const Options* options, const InternalKeyComparator* icmp);
+  virtual ~CompactionPicker();
+
+  // Pick level and inputs for a new compaction.
+  // Returns nullptr if there is no compaction to be done.
+  // Otherwise returns a pointer to a heap-allocated object that
+  // describes the compaction.  Caller should delete the result.
+  virtual Compaction* PickCompaction(Version* version,
+                                     LogBuffer* log_buffer) = 0;
+
+  // Return a compaction object for compacting the range [begin,end] in
+  // the specified level.  Returns nullptr if there is nothing in that
+  // level that overlaps the specified range.  Caller should delete
+  // the result.
+  //
+  // The returned Compaction might not include the whole requested range.
+  // In that case, compaction_end will be set to the next key that needs
+  // compacting. In case the compaction will compact the whole range,
+  // compaction_end will be set to nullptr.
+  // Client is responsible for compaction_end storage -- when called,
+  // *compaction_end should point to valid InternalKey!
+  virtual Compaction* CompactRange(Version* version, int input_level,
+                                   int output_level, const InternalKey* begin,
+                                   const InternalKey* end,
+                                   InternalKey** compaction_end);
+
+  // Free up the files that participated in a compaction
+  void ReleaseCompactionFiles(Compaction* c, Status status);
+
+  // Return the total amount of data that is undergoing
+  // compactions per level
+  void SizeBeingCompacted(std::vector<uint64_t>& sizes);
+
+  // Returns maximum total overlap bytes with grandparent
+  // level (i.e., level+2) before we stop building a single
+  // file in level->level+1 compaction.
+  uint64_t MaxGrandParentOverlapBytes(int level);
+
+  // Returns maximum total bytes of data on a given level.
+  double MaxBytesForLevel(int level);
+
+  // Get the max file size in a given level.
+  uint64_t MaxFileSizeForLevel(int level) const;
+
+ protected:
+  int NumberLevels() const { return num_levels_; }
+
+  // Stores the minimal range that covers all entries in inputs in
+  // *smallest, *largest.
+  // REQUIRES: inputs is not empty
+  void GetRange(const std::vector<FileMetaData*>& inputs, InternalKey* smallest,
+                InternalKey* largest);
+
+  // Stores the minimal range that covers all entries in inputs1 and inputs2
+  // in *smallest, *largest.
+  // REQUIRES: inputs is not empty
+  void GetRange(const std::vector<FileMetaData*>& inputs1,
+                const std::vector<FileMetaData*>& inputs2,
+                InternalKey* smallest, InternalKey* largest);
+
+  // Add more files to the inputs on "level" to make sure that
+  // no newer version of a key is compacted to "level+1" while leaving an older
+  // version in a "level". Otherwise, any Get() will search "level" first,
+  // and will likely return an old/stale value for the key, since it always
+  // searches in increasing order of level to find the value. This could
+  // also scramble the order of merge operands. This function should be
+  // called any time a new Compaction is created, and its inputs_[0] are
+  // populated.
+  //
+  // Will return false if it is impossible to apply this compaction.
+  bool ExpandWhileOverlapping(Compaction* c);
+
+  uint64_t ExpandedCompactionByteSizeLimit(int level);
+
+  // Returns true if any one of the specified files are being compacted
+  bool FilesInCompaction(std::vector<FileMetaData*>& files);
+
+  // Returns true if any one of the parent files are being compacted
+  bool ParentRangeInCompaction(Version* version, const InternalKey* smallest,
+                               const InternalKey* largest, int level,
+                               int* index);
+
+  void SetupOtherInputs(Compaction* c);
+
+  // record all the ongoing compactions for all levels
+  std::vector<std::set<Compaction*>> compactions_in_progress_;
+
+  // Per-level target file size.
+  std::unique_ptr<uint64_t[]> max_file_size_;
+
+  // Per-level max bytes
+  std::unique_ptr<uint64_t[]> level_max_bytes_;
+
+  const Options* const options_;
+
+ private:
+  int num_levels_;
+
+  const InternalKeyComparator* const icmp_;
+};
+
+class UniversalCompactionPicker : public CompactionPicker {
+ public:
+  UniversalCompactionPicker(const Options* options,
+                            const InternalKeyComparator* icmp)
+      : CompactionPicker(options, icmp) {}
+  virtual Compaction* PickCompaction(Version* version,
+                                     LogBuffer* log_buffer) override;
+
+ private:
+  // Pick Universal compaction to limit read amplification
+  Compaction* PickCompactionUniversalReadAmp(Version* version, double score,
+                                             unsigned int ratio,
+                                             unsigned int num_files,
+                                             LogBuffer* log_buffer);
+
+  // Pick Universal compaction to limit space amplification.
+  Compaction* PickCompactionUniversalSizeAmp(Version* version, double score,
+                                             LogBuffer* log_buffer);
+};
+
+class LevelCompactionPicker : public CompactionPicker {
+ public:
+  LevelCompactionPicker(const Options* options,
+                        const InternalKeyComparator* icmp)
+      : CompactionPicker(options, icmp) {}
+  virtual Compaction* PickCompaction(Version* version,
+                                     LogBuffer* log_buffer) override;
+
+ private:
+  // For the specfied level, pick a compaction.
+  // Returns nullptr if there is no compaction to be done.
+  // If level is 0 and there is already a compaction on that level, this
+  // function will return nullptr.
+  Compaction* PickCompactionBySize(Version* version, int level, double score);
+};
+
+class FIFOCompactionPicker : public CompactionPicker {
+ public:
+  FIFOCompactionPicker(const Options* options,
+                       const InternalKeyComparator* icmp)
+      : CompactionPicker(options, icmp) {}
+
+  virtual Compaction* PickCompaction(Version* version,
+                                     LogBuffer* log_buffer) override;
+
+  virtual Compaction* CompactRange(Version* version, int input_level,
+                                   int output_level, const InternalKey* begin,
+                                   const InternalKey* end,
+                                   InternalKey** compaction_end) override;
+};
+
+}  // namespace rocksdb

db/corruption_test.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -10,12 +15,12 @@
 #include <sys/types.h>
 #include "rocksdb/cache.h"
 #include "rocksdb/env.h"
+#include "rocksdb/table.h"
 #include "rocksdb/write_batch.h"
 #include "db/db_impl.h"
 #include "db/filename.h"
 #include "db/log_format.h"
 #include "db/version_set.h"
-#include "table/table.h"
 #include "util/logging.h"
 #include "util/testharness.h"
 #include "util/testutil.h"
@@ -35,7 +40,7 @@ class CorruptionTest {
   CorruptionTest() {
     tiny_cache_ = NewLRUCache(100);
     options_.env = &env_;
-    dbname_ = test::TmpDir() + "/db_test";
+    dbname_ = test::TmpDir() + "/corruption_test";
     DestroyDB(dbname_, options_);
 
     db_ = nullptr;
@@ -90,7 +95,12 @@ class CorruptionTest {
     int bad_values = 0;
     int correct = 0;
     std::string value_space;
-    Iterator* iter = db_->NewIterator(ReadOptions());
+    // Do not verify checksums. If we verify checksums then the
+    // db itself will raise errors because data is corrupted.
+    // Instead, we want the reads to be successful and this test
+    // will detect whether the appropriate corruptions have
+    // occured.
+    Iterator* iter = db_->NewIterator(ReadOptions(false, true));
     for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
       uint64_t key;
       Slice in(iter->key());
@@ -117,24 +127,7 @@ class CorruptionTest {
     ASSERT_GE(max_expected, correct);
   }
 
-  void Corrupt(FileType filetype, int offset, int bytes_to_corrupt) {
-    // Pick file to corrupt
-    std::vector<std::string> filenames;
-    ASSERT_OK(env_.GetChildren(dbname_, &filenames));
-    uint64_t number;
-    FileType type;
-    std::string fname;
-    int picked_number = -1;
-    for (unsigned int i = 0; i < filenames.size(); i++) {
-      if (ParseFileName(filenames[i], &number, &type) &&
-          type == filetype &&
-          int(number) > picked_number) {  // Pick latest file
-        fname = dbname_ + "/" + filenames[i];
-        picked_number = number;
-      }
-    }
-    ASSERT_TRUE(!fname.empty()) << filetype;
-
+  void CorruptFile(const std::string fname, int offset, int bytes_to_corrupt) {
     struct stat sbuf;
     if (stat(fname.c_str(), &sbuf) != 0) {
       const char* msg = strerror(errno);
@@ -167,6 +160,42 @@ class CorruptionTest {
     ASSERT_TRUE(s.ok()) << s.ToString();
   }
 
+  void Corrupt(FileType filetype, int offset, int bytes_to_corrupt) {
+    // Pick file to corrupt
+    std::vector<std::string> filenames;
+    ASSERT_OK(env_.GetChildren(dbname_, &filenames));
+    uint64_t number;
+    FileType type;
+    std::string fname;
+    int picked_number = -1;
+    for (unsigned int i = 0; i < filenames.size(); i++) {
+      if (ParseFileName(filenames[i], &number, &type) &&
+          type == filetype &&
+          static_cast<int>(number) > picked_number) {  // Pick latest file
+        fname = dbname_ + "/" + filenames[i];
+        picked_number = number;
+      }
+    }
+    ASSERT_TRUE(!fname.empty()) << filetype;
+
+    CorruptFile(fname, offset, bytes_to_corrupt);
+  }
+
+  // corrupts exactly one file at level `level`. if no file found at level,
+  // asserts
+  void CorruptTableFileAtLevel(int level, int offset, int bytes_to_corrupt) {
+    std::vector<LiveFileMetaData> metadata;
+    db_->GetLiveFilesMetaData(&metadata);
+    for (const auto& m : metadata) {
+      if (m.level == level) {
+        CorruptFile(dbname_ + "/" + m.name, offset, bytes_to_corrupt);
+        return;
+      }
+    }
+    ASSERT_TRUE(false) << "no file found at level";
+  }
+
+
   int Property(const std::string& name) {
     std::string property;
     int result;
@@ -216,10 +245,15 @@ TEST(CorruptionTest, NewFileErrorDuringWrite) {
   const int num = 3 + (Options().write_buffer_size / kValueSize);
   std::string value_storage;
   Status s;
-  for (int i = 0; s.ok() && i < num; i++) {
+  bool failed = false;
+  for (int i = 0; i < num; i++) {
     WriteBatch batch;
     batch.Put("a", Value(100, &value_storage));
     s = db_->Write(WriteOptions(), &batch);
+    if (!s.ok()) {
+      failed = true;
+    }
+    ASSERT_TRUE(!failed || !s.ok());
   }
   ASSERT_TRUE(!s.ok());
   ASSERT_GE(env_.num_writable_file_errors_, 1);
@@ -230,7 +264,7 @@ TEST(CorruptionTest, NewFileErrorDuringWrite) {
 TEST(CorruptionTest, TableFile) {
   Build(100);
   DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
-  dbi->TEST_CompactMemTable();
+  dbi->TEST_FlushMemTable();
   dbi->TEST_CompactRange(0, nullptr, nullptr);
   dbi->TEST_CompactRange(1, nullptr, nullptr);
 
@@ -241,7 +275,7 @@ TEST(CorruptionTest, TableFile) {
 TEST(CorruptionTest, TableFileIndexData) {
   Build(10000);  // Enough to build multiple Tables
   DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
-  dbi->TEST_CompactMemTable();
+  dbi->TEST_FlushMemTable();
 
   Corrupt(kTableFile, -2000, 500);
   Reopen();
@@ -279,7 +313,7 @@ TEST(CorruptionTest, SequenceNumberRecovery) {
 TEST(CorruptionTest, CorruptedDescriptor) {
   ASSERT_OK(db_->Put(WriteOptions(), "foo", "hello"));
   DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
-  dbi->TEST_CompactMemTable();
+  dbi->TEST_FlushMemTable();
   dbi->TEST_CompactRange(0, nullptr, nullptr);
 
   Corrupt(kDescriptorFile, 0, 1000);
@@ -296,9 +330,9 @@ TEST(CorruptionTest, CorruptedDescriptor) {
 TEST(CorruptionTest, CompactionInputError) {
   Build(10);
   DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
-  dbi->TEST_CompactMemTable();
+  dbi->TEST_FlushMemTable();
   const int last = dbi->MaxMemCompactionLevel();
-  ASSERT_EQ(1, Property("leveldb.num-files-at-level" + NumberToString(last)));
+  ASSERT_EQ(1, Property("rocksdb.num-files-at-level" + NumberToString(last)));
 
   Corrupt(kTableFile, 100, 1);
   Check(9, 9);
@@ -311,29 +345,41 @@ TEST(CorruptionTest, CompactionInputError) {
 TEST(CorruptionTest, CompactionInputErrorParanoid) {
   Options options;
   options.paranoid_checks = true;
-  options.write_buffer_size = 1048576;
+  options.write_buffer_size = 131072;
+  options.max_write_buffer_number = 2;
   Reopen(&options);
   DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
 
-  // Fill levels >= 1 so memtable compaction outputs to level 1
+  // Fill levels >= 1 so memtable flush outputs to level 0
   for (int level = 1; level < dbi->NumberLevels(); level++) {
     dbi->Put(WriteOptions(), "", "begin");
     dbi->Put(WriteOptions(), "~", "end");
-    dbi->TEST_CompactMemTable();
+    dbi->TEST_FlushMemTable();
   }
 
-  Build(10);
-  dbi->TEST_CompactMemTable();
-  ASSERT_EQ(1, Property("leveldb.num-files-at-level0"));
+  options.max_mem_compaction_level = 0;
+  Reopen(&options);
 
-  Corrupt(kTableFile, 100, 1);
+  dbi = reinterpret_cast<DBImpl*>(db_);
+  Build(10);
+  dbi->TEST_FlushMemTable();
+  dbi->TEST_WaitForCompact();
+  ASSERT_EQ(1, Property("rocksdb.num-files-at-level0"));
+
+  CorruptTableFileAtLevel(0, 100, 1);
   Check(9, 9);
 
   // Write must eventually fail because of corrupted table
   Status s;
   std::string tmp1, tmp2;
-  for (int i = 0; i < 10000 && s.ok(); i++) {
+  bool failed = false;
+  for (int i = 0; i < 10000; i++) {
     s = db_->Put(WriteOptions(), Key(i, &tmp1), Value(i, &tmp2));
+    if (!s.ok()) {
+      failed = true;
+    }
+    // if one write failed, every subsequent write must fail, too
+    ASSERT_TRUE(!failed || !s.ok()) << "write did not fail in a corrupted db";
   }
   ASSERT_TRUE(!s.ok()) << "write did not fail in corrupted paranoid db";
 }
@@ -341,7 +387,7 @@ TEST(CorruptionTest, CompactionInputErrorParanoid) {
 TEST(CorruptionTest, UnrelatedKeys) {
   Build(10);
   DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
-  dbi->TEST_CompactMemTable();
+  dbi->TEST_FlushMemTable();
   Corrupt(kTableFile, 100, 1);
 
   std::string tmp1, tmp2;
@@ -349,11 +395,44 @@ TEST(CorruptionTest, UnrelatedKeys) {
   std::string v;
   ASSERT_OK(db_->Get(ReadOptions(), Key(1000, &tmp1), &v));
   ASSERT_EQ(Value(1000, &tmp2).ToString(), v);
-  dbi->TEST_CompactMemTable();
+  dbi->TEST_FlushMemTable();
   ASSERT_OK(db_->Get(ReadOptions(), Key(1000, &tmp1), &v));
   ASSERT_EQ(Value(1000, &tmp2).ToString(), v);
 }
 
+TEST(CorruptionTest, FileSystemStateCorrupted) {
+  for (int iter = 0; iter < 2; ++iter) {
+    Options options;
+    options.paranoid_checks = true;
+    options.create_if_missing = true;
+    Reopen(&options);
+    Build(10);
+    ASSERT_OK(db_->Flush(FlushOptions()));
+    DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
+    std::vector<LiveFileMetaData> metadata;
+    dbi->GetLiveFilesMetaData(&metadata);
+    ASSERT_GT(metadata.size(), size_t(0));
+    std::string filename = dbname_ + metadata[0].name;
+
+    delete db_;
+    db_ = nullptr;
+
+    if (iter == 0) {  // corrupt file size
+      unique_ptr<WritableFile> file;
+      env_.NewWritableFile(filename, &file, EnvOptions());
+      file->Append(Slice("corrupted sst"));
+      file.reset();
+    } else {  // delete the file
+      env_.DeleteFile(filename);
+    }
+
+    Status x = TryReopen(&options);
+    ASSERT_TRUE(x.IsCorruption());
+    DestroyDB(dbname_, options_);
+    Reopen(&options);
+  }
+}
+
 }  // namespace rocksdb
 
 int main(int argc, char** argv) {

db/db_filesnapshot.cc

@@ -1,7 +1,16 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2012 Facebook.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#ifndef ROCKSDB_LITE
+
+#define __STDC_FORMAT_MACROS
+#include <inttypes.h>
 #include <algorithm>
 #include <string>
 #include <stdint.h>
@@ -12,20 +21,48 @@
 #include "rocksdb/env.h"
 #include "port/port.h"
 #include "util/mutexlock.h"
+#include "util/sync_point.h"
 
 namespace rocksdb {
 
 Status DBImpl::DisableFileDeletions() {
   MutexLock l(&mutex_);
-  disable_delete_obsolete_files_ = true;
-  Log(options_.info_log, "File Deletions Disabled");
+  ++disable_delete_obsolete_files_;
+  if (disable_delete_obsolete_files_ == 1) {
+    Log(options_.info_log, "File Deletions Disabled");
+  } else {
+    Log(options_.info_log,
+        "File Deletions Disabled, but already disabled. Counter: %d",
+        disable_delete_obsolete_files_);
+  }
   return Status::OK();
 }
 
-Status DBImpl::EnableFileDeletions() {
-  MutexLock l(&mutex_);
-  disable_delete_obsolete_files_ = false;
-  Log(options_.info_log, "File Deletions Enabled");
+Status DBImpl::EnableFileDeletions(bool force) {
+  DeletionState deletion_state;
+  bool should_purge_files = false;
+  {
+    MutexLock l(&mutex_);
+    if (force) {
+      // if force, we need to enable file deletions right away
+      disable_delete_obsolete_files_ = 0;
+    } else if (disable_delete_obsolete_files_ > 0) {
+      --disable_delete_obsolete_files_;
+    }
+    if (disable_delete_obsolete_files_ == 0)  {
+      Log(options_.info_log, "File Deletions Enabled");
+      should_purge_files = true;
+      FindObsoleteFiles(deletion_state, true);
+    } else {
+      Log(options_.info_log,
+          "File Deletions Enable, but not really enabled. Counter: %d",
+          disable_delete_obsolete_files_);
+    }
+  }
+  if (should_purge_files)  {
+    PurgeObsoleteFiles(deletion_state);
+  }
+  LogFlush(options_.info_log);
   return Status::OK();
 }
 
@@ -35,21 +72,36 @@ Status DBImpl::GetLiveFiles(std::vector<std::string>& ret,
 
   *manifest_file_size = 0;
 
+  mutex_.Lock();
+
   if (flush_memtable) {
     // flush all dirty data to disk.
-    Status status =  Flush(FlushOptions());
+    Status status;
+    for (auto cfd : *versions_->GetColumnFamilySet()) {
+      cfd->Ref();
+      mutex_.Unlock();
+      status = FlushMemTable(cfd, FlushOptions());
+      mutex_.Lock();
+      cfd->Unref();
+      if (!status.ok()) {
+        break;
+      }
+    }
+    versions_->GetColumnFamilySet()->FreeDeadColumnFamilies();
+
     if (!status.ok()) {
+      mutex_.Unlock();
       Log(options_.info_log, "Cannot Flush data %s\n",
           status.ToString().c_str());
       return status;
     }
   }
 
-  MutexLock l(&mutex_);
-
   // Make a set of all of the live *.sst files
-  std::set<uint64_t> live;
-  versions_->AddLiveFilesCurrentVersion(&live);
+  std::vector<FileDescriptor> live;
+  for (auto cfd : *versions_->GetColumnFamilySet()) {
+    cfd->current()->AddLiveFiles(&live);
+  }
 
   ret.clear();
   ret.reserve(live.size() + 2); //*.sst + CURRENT + MANIFEST
@@ -57,7 +109,7 @@ Status DBImpl::GetLiveFiles(std::vector<std::string>& ret,
   // create names of the live files. The names are not absolute
   // paths, instead they are relative to dbname_;
   for (auto live_file : live) {
-    ret.push_back(TableFileName("", live_file));
+    ret.push_back(MakeTableFileName("", live_file.GetNumber()));
   }
 
   ret.push_back(CurrentFileName(""));
@@ -66,49 +118,62 @@ Status DBImpl::GetLiveFiles(std::vector<std::string>& ret,
   // find length of manifest file while holding the mutex lock
   *manifest_file_size = versions_->ManifestFileSize();
 
+  mutex_.Unlock();
   return Status::OK();
 }
 
 Status DBImpl::GetSortedWalFiles(VectorLogPtr& files) {
-  // First get sorted files in archive dir, then append sorted files from main
-  // dir to maintain sorted order
-
-  // list wal files in archive dir.
+  // First get sorted files in db dir, then get sorted files from archived
+  // dir, to avoid a race condition where a log file is moved to archived
+  // dir in between.
   Status s;
-  std::string archivedir = ArchivalDirectory(dbname_);
+  // list wal files in main db dir.
+  VectorLogPtr logs;
+  s = GetSortedWalsOfType(options_.wal_dir, logs, kAliveLogFile);
+  if (!s.ok()) {
+    return s;
+  }
+
+  // Reproduce the race condition where a log file is moved
+  // to archived dir, between these two sync points, used in
+  // (DBTest,TransactionLogIteratorRace)
+  TEST_SYNC_POINT("DBImpl::GetSortedWalFiles:1");
+  TEST_SYNC_POINT("DBImpl::GetSortedWalFiles:2");
+
+  files.clear();
+  // list wal files in archive dir.
+  std::string archivedir = ArchivalDirectory(options_.wal_dir);
   if (env_->FileExists(archivedir)) {
-    s = AppendSortedWalsOfType(archivedir, files, kArchivedLogFile);
+    s = GetSortedWalsOfType(archivedir, files, kArchivedLogFile);
     if (!s.ok()) {
       return s;
     }
   }
-  // list wal files in main db dir.
-  return AppendSortedWalsOfType(dbname_, files, kAliveLogFile);
-}
 
-Status DBImpl::DeleteWalFiles(const VectorLogPtr& files) {
-  Status s;
-  std::string archivedir = ArchivalDirectory(dbname_);
-  std::string files_not_deleted;
-  for (const auto& wal : files) {
-    /* Try deleting in the dir that pathname points to for the logfile.
-       This may fail if we try to delete a log file which was live when captured
-       but is archived now. Try deleting it from archive also
-     */
-    Status st = env_->DeleteFile(dbname_ + "/" + wal->PathName());
-    if (!st.ok()) {
-      if (wal->Type() == kAliveLogFile &&
-          env_->DeleteFile(LogFileName(archivedir, wal->LogNumber())).ok()) {
-        continue;
-      }
-      files_not_deleted.append(wal->PathName());
+  uint64_t latest_archived_log_number = 0;
+  if (!files.empty()) {
+    latest_archived_log_number = files.back()->LogNumber();
+    Log(options_.info_log, "Latest Archived log: %" PRIu64,
+        latest_archived_log_number);
+  }
+
+  files.reserve(files.size() + logs.size());
+  for (auto& log : logs) {
+    if (log->LogNumber() > latest_archived_log_number) {
+      files.push_back(std::move(log));
+    } else {
+      // When the race condition happens, we could see the
+      // same log in both db dir and archived dir. Simply
+      // ignore the one in db dir. Note that, if we read
+      // archived dir first, we would have missed the log file.
+      Log(options_.info_log, "%s already moved to archive",
+          log->PathName().c_str());
     }
   }
-  if (!files_not_deleted.empty()) {
-    return Status::IOError("Deleted all requested files except: " +
-                           files_not_deleted);
-  }
-  return Status::OK();
+
+  return s;
 }
 
 }
+
+#endif  // ROCKSDB_LITE

db/db_impl.h

@@ -1,28 +1,37 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
-
-#ifndef STORAGE_LEVELDB_DB_DB_IMPL_H_
-#define STORAGE_LEVELDB_DB_DB_IMPL_H_
+#pragma once
 
 #include <atomic>
 #include <deque>
+#include <limits>
 #include <set>
+#include <utility>
 #include <vector>
+#include <string>
+
 #include "db/dbformat.h"
 #include "db/log_writer.h"
 #include "db/snapshot.h"
+#include "db/column_family.h"
+#include "db/version_edit.h"
+#include "memtable_list.h"
+#include "port/port.h"
 #include "rocksdb/db.h"
 #include "rocksdb/env.h"
 #include "rocksdb/memtablerep.h"
 #include "rocksdb/transaction_log.h"
-#include "port/port.h"
+#include "util/autovector.h"
 #include "util/stats_logger.h"
-#include "memtablelist.h"
-
-#ifdef USE_SCRIBE
-#include "scribe/scribe_logger.h"
-#endif
+#include "util/stop_watch.h"
+#include "util/thread_local.h"
+#include "db/internal_stats.h"
 
 namespace rocksdb {
 
@@ -31,69 +40,128 @@ class TableCache;
 class Version;
 class VersionEdit;
 class VersionSet;
+class CompactionFilterV2;
+class Arena;
 
 class DBImpl : public DB {
  public:
-  DBImpl(const Options& options, const std::string& dbname);
+  DBImpl(const DBOptions& options, const std::string& dbname);
   virtual ~DBImpl();
 
   // Implementations of the DB interface
-  virtual Status Put(const WriteOptions&, const Slice& key, const Slice& value);
-  virtual Status Merge(const WriteOptions&, const Slice& key,
+  using DB::Put;
+  virtual Status Put(const WriteOptions& options,
+                     ColumnFamilyHandle* column_family, const Slice& key,
+                     const Slice& value);
+  using DB::Merge;
+  virtual Status Merge(const WriteOptions& options,
+                       ColumnFamilyHandle* column_family, const Slice& key,
                        const Slice& value);
-  virtual Status Delete(const WriteOptions&, const Slice& key);
+  using DB::Delete;
+  virtual Status Delete(const WriteOptions& options,
+                        ColumnFamilyHandle* column_family, const Slice& key);
+  using DB::Write;
   virtual Status Write(const WriteOptions& options, WriteBatch* updates);
+  using DB::Get;
   virtual Status Get(const ReadOptions& options,
-                     const Slice& key,
+                     ColumnFamilyHandle* column_family, const Slice& key,
                      std::string* value);
-  virtual std::vector<Status> MultiGet(const ReadOptions& options,
-                                       const std::vector<Slice>& keys,
-                                       std::vector<std::string>* values);
+  using DB::MultiGet;
+  virtual std::vector<Status> MultiGet(
+      const ReadOptions& options,
+      const std::vector<ColumnFamilyHandle*>& column_family,
+      const std::vector<Slice>& keys, std::vector<std::string>* values);
+
+  virtual Status CreateColumnFamily(const ColumnFamilyOptions& options,
+                                    const std::string& column_family,
+                                    ColumnFamilyHandle** handle);
+  virtual Status DropColumnFamily(ColumnFamilyHandle* column_family);
 
   // Returns false if key doesn't exist in the database and true if it may.
   // If value_found is not passed in as null, then return the value if found in
   // memory. On return, if value was found, then value_found will be set to true
   // , otherwise false.
+  using DB::KeyMayExist;
   virtual bool KeyMayExist(const ReadOptions& options,
-                           const Slice& key,
-                           std::string* value,
-                           bool* value_found = nullptr);
-  virtual Iterator* NewIterator(const ReadOptions&);
+                           ColumnFamilyHandle* column_family, const Slice& key,
+                           std::string* value, bool* value_found = nullptr);
+  using DB::NewIterator;
+  virtual Iterator* NewIterator(const ReadOptions& options,
+                                ColumnFamilyHandle* column_family);
+  virtual Status NewIterators(
+      const ReadOptions& options,
+      const std::vector<ColumnFamilyHandle*>& column_families,
+      std::vector<Iterator*>* iterators);
   virtual const Snapshot* GetSnapshot();
   virtual void ReleaseSnapshot(const Snapshot* snapshot);
-  virtual bool GetProperty(const Slice& property, std::string* value);
-  virtual void GetApproximateSizes(const Range* range, int n, uint64_t* sizes);
-  virtual void CompactRange(const Slice* begin, const Slice* end,
-                            bool reduce_level = false, int target_level = -1);
-  virtual int NumberLevels();
-  virtual int MaxMemCompactionLevel();
-  virtual int Level0StopWriteTrigger();
-  virtual Status Flush(const FlushOptions& options);
+  using DB::GetProperty;
+  virtual bool GetProperty(ColumnFamilyHandle* column_family,
+                           const Slice& property, std::string* value);
+  using DB::GetApproximateSizes;
+  virtual void GetApproximateSizes(ColumnFamilyHandle* column_family,
+                                   const Range* range, int n, uint64_t* sizes);
+  using DB::CompactRange;
+  virtual Status CompactRange(ColumnFamilyHandle* column_family,
+                              const Slice* begin, const Slice* end,
+                              bool reduce_level = false, int target_level = -1);
+
+  using DB::NumberLevels;
+  virtual int NumberLevels(ColumnFamilyHandle* column_family);
+  using DB::MaxMemCompactionLevel;
+  virtual int MaxMemCompactionLevel(ColumnFamilyHandle* column_family);
+  using DB::Level0StopWriteTrigger;
+  virtual int Level0StopWriteTrigger(ColumnFamilyHandle* column_family);
+  virtual const std::string& GetName() const;
+  virtual Env* GetEnv() const;
+  using DB::GetOptions;
+  virtual const Options& GetOptions(ColumnFamilyHandle* column_family) const;
+  using DB::Flush;
+  virtual Status Flush(const FlushOptions& options,
+                       ColumnFamilyHandle* column_family);
+
+  virtual SequenceNumber GetLatestSequenceNumber() const;
+
+#ifndef ROCKSDB_LITE
   virtual Status DisableFileDeletions();
-  virtual Status EnableFileDeletions();
+  virtual Status EnableFileDeletions(bool force);
+  // All the returned filenames start with "/"
   virtual Status GetLiveFiles(std::vector<std::string>&,
                               uint64_t* manifest_file_size,
                               bool flush_memtable = true);
   virtual Status GetSortedWalFiles(VectorLogPtr& files);
-  virtual Status DeleteWalFiles(const VectorLogPtr& files);
-  virtual SequenceNumber GetLatestSequenceNumber();
-  virtual Status GetUpdatesSince(SequenceNumber seq_number,
-                                 unique_ptr<TransactionLogIterator>* iter);
+
+  virtual Status GetUpdatesSince(
+      SequenceNumber seq_number, unique_ptr<TransactionLogIterator>* iter,
+      const TransactionLogIterator::ReadOptions&
+          read_options = TransactionLogIterator::ReadOptions());
   virtual Status DeleteFile(std::string name);
 
-  virtual void GetLiveFilesMetaData(
-    std::vector<LiveFileMetaData> *metadata);
+  virtual void GetLiveFilesMetaData(std::vector<LiveFileMetaData>* metadata);
+#endif  // ROCKSDB_LITE
 
+  // checks if all live files exist on file system and that their file sizes
+  // match to our in-memory records
+  virtual Status CheckConsistency();
+
+  virtual Status GetDbIdentity(std::string& identity);
+
+  Status RunManualCompaction(ColumnFamilyData* cfd, int input_level,
+                             int output_level, const Slice* begin,
+                             const Slice* end);
+
+#ifndef ROCKSDB_LITE
   // Extra methods (for testing) that are not in the public DB interface
+  // Implemented in db_impl_debug.cc
 
   // Compact any files in the named level that overlap [*begin, *end]
-  void TEST_CompactRange(int level, const Slice* begin, const Slice* end);
+  Status TEST_CompactRange(int level, const Slice* begin, const Slice* end,
+                           ColumnFamilyHandle* column_family = nullptr);
 
-  // Force current memtable contents to be compacted.
-  Status TEST_CompactMemTable();
+  // Force current memtable contents to be flushed.
+  Status TEST_FlushMemTable(bool wait = true);
 
   // Wait for memtable compaction
-  Status TEST_WaitForCompactMemTable();
+  Status TEST_WaitForFlushMemTable(ColumnFamilyHandle* column_family = nullptr);
 
   // Wait for any compaction
   Status TEST_WaitForCompact();
@@ -101,14 +169,13 @@ class DBImpl : public DB {
   // Return an internal iterator over the current state of the database.
   // The keys of this iterator are internal keys (see format.h).
   // The returned iterator should be deleted when no longer needed.
-  Iterator* TEST_NewInternalIterator();
+  Iterator* TEST_NewInternalIterator(ColumnFamilyHandle* column_family =
+                                         nullptr);
 
   // Return the maximum overlapping data (in bytes) at next level for any
   // file at a level >= 1.
-  int64_t TEST_MaxNextLevelOverlappingBytes();
-
-  // Simulate a db crash, no elegant closing of database.
-  void TEST_Destroy_DBImpl();
+  int64_t TEST_MaxNextLevelOverlappingBytes(ColumnFamilyHandle* column_family =
+                                                nullptr);
 
   // Return the current manifest file no.
   uint64_t TEST_Current_Manifest_FileNo();
@@ -116,37 +183,136 @@ class DBImpl : public DB {
   // Trigger's a background call for testing.
   void TEST_PurgeObsoleteteWAL();
 
+  // get total level0 file size. Only for testing.
+  uint64_t TEST_GetLevel0TotalSize();
+
+  void TEST_SetDefaultTimeToCheck(uint64_t default_interval_to_delete_obsolete_WAL)
+  {
+    default_interval_to_delete_obsolete_WAL_ = default_interval_to_delete_obsolete_WAL;
+  }
+
+  void TEST_GetFilesMetaData(ColumnFamilyHandle* column_family,
+                             std::vector<std::vector<FileMetaData>>* metadata);
+
+  Status TEST_ReadFirstRecord(const WalFileType type, const uint64_t number,
+                              SequenceNumber* sequence);
+
+  Status TEST_ReadFirstLine(const std::string& fname, SequenceNumber* sequence);
+#endif  // NDEBUG
+
+  // Structure to store information for candidate files to delete.
+  struct CandidateFileInfo {
+    std::string file_name;
+    uint32_t path_id;
+    CandidateFileInfo(std::string name, uint32_t path)
+        : file_name(name), path_id(path) {}
+    bool operator==(const CandidateFileInfo& other) const {
+      return file_name == other.file_name && path_id == other.path_id;
+    }
+  };
+
+  // needed for CleanupIteratorState
+  struct DeletionState {
+    inline bool HaveSomethingToDelete() const {
+      return  candidate_files.size() ||
+        sst_delete_files.size() ||
+        log_delete_files.size();
+    }
+
+    // a list of all files that we'll consider deleting
+    // (every once in a while this is filled up with all files
+    // in the DB directory)
+    std::vector<CandidateFileInfo> candidate_files;
+
+    // the list of all live sst files that cannot be deleted
+    std::vector<FileDescriptor> sst_live;
+
+    // a list of sst files that we need to delete
+    std::vector<FileMetaData*> sst_delete_files;
+
+    // a list of log files that we need to delete
+    std::vector<uint64_t> log_delete_files;
+
+    // a list of memtables to be free
+    autovector<MemTable*> memtables_to_free;
+
+    autovector<SuperVersion*> superversions_to_free;
+
+    SuperVersion* new_superversion;  // if nullptr no new superversion
+
+    // the current manifest_file_number, log_number and prev_log_number
+    // that corresponds to the set of files in 'live'.
+    uint64_t manifest_file_number, pending_manifest_file_number, log_number,
+        prev_log_number;
+
+    explicit DeletionState(bool create_superversion = false) {
+      manifest_file_number = 0;
+      pending_manifest_file_number = 0;
+      log_number = 0;
+      prev_log_number = 0;
+      new_superversion = create_superversion ? new SuperVersion() : nullptr;
+    }
+
+    ~DeletionState() {
+      // free pending memtables
+      for (auto m : memtables_to_free) {
+        delete m;
+      }
+      // free superversions
+      for (auto s : superversions_to_free) {
+        delete s;
+      }
+      // if new_superversion was not used, it will be non-nullptr and needs
+      // to be freed here
+      delete new_superversion;
+    }
+  };
+
+  // Returns the list of live files in 'live' and the list
+  // of all files in the filesystem in 'candidate_files'.
+  // If force == false and the last call was less than
+  // options_.delete_obsolete_files_period_micros microseconds ago,
+  // it will not fill up the deletion_state
+  void FindObsoleteFiles(DeletionState& deletion_state,
+                         bool force,
+                         bool no_full_scan = false);
+
+  // Diffs the files listed in filenames and those that do not
+  // belong to live files are posibly removed. Also, removes all the
+  // files in sst_delete_files and log_delete_files.
+  // It is not necessary to hold the mutex when invoking this method.
+  void PurgeObsoleteFiles(DeletionState& deletion_state);
+
+  ColumnFamilyHandle* DefaultColumnFamily() const;
+
  protected:
   Env* const env_;
   const std::string dbname_;
   unique_ptr<VersionSet> versions_;
-  const InternalKeyComparator internal_comparator_;
-  const Options options_;  // options_.comparator == &internal_comparator_
+  const DBOptions options_;
 
-  const Comparator* user_comparator() const {
-    return internal_comparator_.user_comparator();
-  }
-
-  MemTable* GetMemTable() {
-    return mem_;
-  }
-
-  Iterator* NewInternalIterator(const ReadOptions&,
-                                SequenceNumber* latest_snapshot);
+  Iterator* NewInternalIterator(const ReadOptions&, ColumnFamilyData* cfd,
+                                SuperVersion* super_version,
+                                Arena* arena = nullptr);
 
  private:
   friend class DB;
+  friend class InternalStats;
+#ifndef ROCKSDB_LITE
+  friend class TailingIterator;
+  friend class ForwardIterator;
+#endif
+  friend struct SuperVersion;
   struct CompactionState;
   struct Writer;
-  struct DeletionState;
 
   Status NewDB();
 
   // Recover the descriptor from persistent storage.  May do a significant
   // amount of work to recover recently logged updates.  Any changes to
   // be made to the descriptor are added to *edit.
-  Status Recover(VersionEdit* edit, MemTable* external_table = nullptr,
-      bool error_if_log_file_exist = false);
+  Status Recover(const std::vector<ColumnFamilyDescriptor>& column_families,
+                 bool read_only = false, bool error_if_log_file_exist = false);
 
   void MaybeIgnoreError(Status* s) const;
 
@@ -155,109 +321,148 @@ class DBImpl : public DB {
   // Delete any unneeded files and stale in-memory entries.
   void DeleteObsoleteFiles();
 
-  // Compact the in-memory write buffer to disk.  Switches to a new
+  // Flush the in-memory write buffer to storage.  Switches to a new
   // log-file/memtable and writes a new descriptor iff successful.
-  Status CompactMemTable(bool* madeProgress = nullptr);
+  Status FlushMemTableToOutputFile(ColumnFamilyData* cfd, bool* madeProgress,
+                                   DeletionState& deletion_state,
+                                   LogBuffer* log_buffer);
 
-  Status RecoverLogFile(uint64_t log_number,
-                        VersionEdit* edit,
-                        SequenceNumber* max_sequence,
-                        MemTable* external_table);
+  Status RecoverLogFile(uint64_t log_number, SequenceNumber* max_sequence,
+                        bool read_only);
 
   // The following two methods are used to flush a memtable to
   // storage. The first one is used atdatabase RecoveryTime (when the
   // database is opened) and is heavyweight because it holds the mutex
   // for the entire period. The second method WriteLevel0Table supports
   // concurrent flush memtables to storage.
-  Status WriteLevel0TableForRecovery(MemTable* mem, VersionEdit* edit);
-  Status WriteLevel0Table(std::vector<MemTable*> &mems, VersionEdit* edit,
-                                uint64_t* filenumber);
+  Status WriteLevel0TableForRecovery(ColumnFamilyData* cfd, MemTable* mem,
+                                     VersionEdit* edit);
+  Status WriteLevel0Table(ColumnFamilyData* cfd, autovector<MemTable*>& mems,
+                          VersionEdit* edit, uint64_t* filenumber,
+                          LogBuffer* log_buffer);
 
-  uint64_t SlowdownAmount(int n, int top, int bottom);
-  Status MakeRoomForWrite(bool force /* compact even if there is room? */);
-  WriteBatch* BuildBatchGroup(Writer** last_writer);
+  uint64_t SlowdownAmount(int n, double bottom, double top);
+
+  // TODO(icanadi) free superversion_to_free and old_log outside of mutex
+  Status MakeRoomForWrite(ColumnFamilyData* cfd,
+                          bool force /* flush even if there is room? */,
+                          autovector<SuperVersion*>* superversions_to_free,
+                          autovector<log::Writer*>* logs_to_free,
+                          uint64_t expiration_time);
+
+  void BuildBatchGroup(Writer** last_writer,
+                       autovector<WriteBatch*>* write_batch_group);
 
   // Force current memtable contents to be flushed.
-  Status FlushMemTable(const FlushOptions& options);
+  Status FlushMemTable(ColumnFamilyData* cfd, const FlushOptions& options);
 
-  // Wait for memtable compaction
-  Status WaitForCompactMemTable();
+  // Wait for memtable flushed
+  Status WaitForFlushMemTable(ColumnFamilyData* cfd);
+
+  void RecordFlushIOStats();
+  void RecordCompactionIOStats();
 
   void MaybeScheduleLogDBDeployStats();
+
+#ifndef ROCKSDB_LITE
   static void BGLogDBDeployStats(void* db);
   void LogDBDeployStats();
+#endif  // ROCKSDB_LITE
 
-  void MaybeScheduleCompaction();
+  void MaybeScheduleFlushOrCompaction();
   static void BGWorkCompaction(void* db);
   static void BGWorkFlush(void* db);
   void BackgroundCallCompaction();
   void BackgroundCallFlush();
-  Status BackgroundCompaction(bool* madeProgress,DeletionState& deletion_state);
-  Status BackgroundFlush();
-  void CleanupCompaction(CompactionState* compact);
-  Status DoCompactionWork(CompactionState* compact);
+  Status BackgroundCompaction(bool* madeProgress, DeletionState& deletion_state,
+                              LogBuffer* log_buffer);
+  Status BackgroundFlush(bool* madeProgress, DeletionState& deletion_state,
+                         LogBuffer* log_buffer);
+  void CleanupCompaction(CompactionState* compact, Status status);
+  Status DoCompactionWork(CompactionState* compact,
+                          DeletionState& deletion_state,
+                          LogBuffer* log_buffer);
+
+  // This function is called as part of compaction. It enables Flush process to
+  // preempt compaction, since it's higher prioirty
+  // Returns: micros spent executing
+  uint64_t CallFlushDuringCompaction(ColumnFamilyData* cfd,
+                                     DeletionState& deletion_state,
+                                     LogBuffer* log_buffer);
+
+  // Call compaction filter if is_compaction_v2 is not true. Then iterate
+  // through input and compact the kv-pairs
+  Status ProcessKeyValueCompaction(
+    bool is_snapshot_supported,
+    SequenceNumber visible_at_tip,
+    SequenceNumber earliest_snapshot,
+    SequenceNumber latest_snapshot,
+    DeletionState& deletion_state,
+    bool bottommost_level,
+    int64_t& imm_micros,
+    Iterator* input,
+    CompactionState* compact,
+    bool is_compaction_v2,
+    LogBuffer* log_buffer);
+
+  // Call compaction_filter_v2->Filter() on kv-pairs in compact
+  void CallCompactionFilterV2(CompactionState* compact,
+    CompactionFilterV2* compaction_filter_v2);
 
   Status OpenCompactionOutputFile(CompactionState* compact);
   Status FinishCompactionOutputFile(CompactionState* compact, Iterator* input);
-  Status InstallCompactionResults(CompactionState* compact);
+  Status InstallCompactionResults(CompactionState* compact,
+                                  LogBuffer* log_buffer);
   void AllocateCompactionOutputFileNumbers(CompactionState* compact);
   void ReleaseCompactionUnusedFileNumbers(CompactionState* compact);
 
-
-  // Returns the list of live files in 'live' and the list
-  // of all files in the filesystem in 'allfiles'.
-  void FindObsoleteFiles(DeletionState& deletion_state);
-
-  // Diffs the files listed in filenames and those that do not
-  // belong to live files are posibly removed. If the removed file
-  // is a sst file, then it returns the file number in files_to_evict.
-  void PurgeObsoleteFiles(DeletionState& deletion_state);
-
-  // Removes the file listed in files_to_evict from the table_cache
-  void EvictObsoleteFiles(DeletionState& deletion_state);
-
-  Status DeleteLogFile(uint64_t number);
-
+#ifdef ROCKSDB_LITE
+  void PurgeObsoleteWALFiles() {
+    // this function is used for archiving WAL files. we don't need this in
+    // ROCKSDB_LITE
+  }
+#else
   void PurgeObsoleteWALFiles();
 
-  Status AppendSortedWalsOfType(const std::string& path,
-                                VectorLogPtr& log_files,
-                                WalFileType type);
+  Status GetSortedWalsOfType(const std::string& path,
+                             VectorLogPtr& log_files,
+                             WalFileType type);
 
   // Requires: all_logs should be sorted with earliest log file first
   // Retains all log files in all_logs which contain updates with seq no.
   // Greater Than or Equal to the requested SequenceNumber.
   Status RetainProbableWalFiles(VectorLogPtr& all_logs,
                                 const SequenceNumber target);
-  //  return true if
-  bool CheckWalFileExistsAndEmpty(const WalFileType type,
-                                  const uint64_t number);
 
   Status ReadFirstRecord(const WalFileType type, const uint64_t number,
-                         WriteBatch* const result);
+                         SequenceNumber* sequence);
 
-  Status ReadFirstLine(const std::string& fname, WriteBatch* const batch);
+  Status ReadFirstLine(const std::string& fname, SequenceNumber* sequence);
+#endif  // ROCKSDB_LITE
 
   void PrintStatistics();
 
-  // dump leveldb.stats to LOG
+  // dump rocksdb.stats to LOG
   void MaybeDumpStats();
 
+  // Return true if the current db supports snapshot.  If the current
+  // DB does not support snapshot, then calling GetSnapshot() will always
+  // return nullptr.
+  //
+  // @see GetSnapshot()
+  virtual bool IsSnapshotSupported() const;
+
   // Return the minimum empty level that could hold the total data in the
   // input level. Return the input level, if such level could not be found.
-  int FindMinimumEmptyLevelFitting(int level);
+  int FindMinimumEmptyLevelFitting(ColumnFamilyData* cfd, int level);
 
   // Move the files in the input level to the target level.
   // If target_level < 0, automatically calculate the minimum level that could
   // hold the data set.
-  void ReFitLevel(int level, int target_level = -1);
-
-  // Constant after construction
-  const InternalFilterPolicy internal_filter_policy_;
-  bool owns_info_log_;
+  Status ReFitLevel(ColumnFamilyData* cfd, int level, int target_level = -1);
 
   // table_cache_ provides its own synchronization
-  unique_ptr<TableCache> table_cache_;
+  std::shared_ptr<Cache> table_cache_;
 
   // Lock over the persistent DB state.  Non-nullptr iff successfully acquired.
   FileLock* db_lock_;
@@ -265,28 +470,69 @@ class DBImpl : public DB {
   // State below is protected by mutex_
   port::Mutex mutex_;
   port::AtomicPointer shutting_down_;
-  port::CondVar bg_cv_;          // Signalled when background work finishes
-  std::shared_ptr<MemTableRepFactory> mem_rep_factory_;
-  MemTable* mem_;
-  MemTableList imm_;             // Memtable that are not changing
+  // This condition variable is signaled on these conditions:
+  // * whenever bg_compaction_scheduled_ goes down to 0
+  // * if bg_manual_only_ > 0, whenever a compaction finishes, even if it hasn't
+  // made any progress
+  // * whenever a compaction made any progress
+  // * whenever bg_flush_scheduled_ value decreases (i.e. whenever a flush is
+  // done, even if it didn't make any progress)
+  // * whenever there is an error in background flush or compaction
+  // * whenever bg_logstats_scheduled_ turns to false
+  port::CondVar bg_cv_;
   uint64_t logfile_number_;
   unique_ptr<log::Writer> log_;
+  bool log_empty_;
+  ColumnFamilyHandleImpl* default_cf_handle_;
+  unique_ptr<ColumnFamilyMemTablesImpl> column_family_memtables_;
+  struct LogFileNumberSize {
+    explicit LogFileNumberSize(uint64_t _number)
+        : number(_number), size(0), getting_flushed(false) {}
+    void AddSize(uint64_t new_size) { size += new_size; }
+    uint64_t number;
+    uint64_t size;
+    bool getting_flushed;
+  };
+  std::deque<LogFileNumberSize> alive_log_files_;
+  uint64_t total_log_size_;
+  // only used for dynamically adjusting max_total_wal_size. it is a sum of
+  // [write_buffer_size * max_write_buffer_number] over all column families
+  uint64_t max_total_in_memory_state_;
+  // If true, we have only one (default) column family. We use this to optimize
+  // some code-paths
+  bool single_column_family_mode_;
 
   std::string host_name_;
 
+  std::unique_ptr<Directory> db_directory_;
+
   // Queue of writers.
   std::deque<Writer*> writers_;
   WriteBatch tmp_batch_;
 
   SnapshotList snapshots_;
 
+  // cache for ReadFirstRecord() calls
+  std::unordered_map<uint64_t, SequenceNumber> read_first_record_cache_;
+  port::Mutex read_first_record_cache_mutex_;
+
   // Set of table files to protect from deletion because they are
   // part of ongoing compactions.
-  std::set<uint64_t> pending_outputs_;
+  // map from pending file number ID to their path IDs.
+  FileNumToPathIdMap pending_outputs_;
 
-  // count how many background compaction been scheduled or is running?
+  // At least one compaction or flush job is pending but not yet scheduled
+  // because of the max background thread limit.
+  bool bg_schedule_needed_;
+
+  // count how many background compactions are running or have been scheduled
   int bg_compaction_scheduled_;
 
+  // If non-zero, MaybeScheduleFlushOrCompaction() will only schedule manual
+  // compactions (if manual_compaction_ is not null). This mechanism enables
+  // manual compactions to wait until all other compactions are finished.
+  int bg_manual_only_;
+
   // number of background memtable flush jobs, submitted to the HIGH pool
   int bg_flush_scheduled_;
 
@@ -295,8 +541,11 @@ class DBImpl : public DB {
 
   // Information for a manual compaction
   struct ManualCompaction {
-    int level;
+    ColumnFamilyData* cfd;
+    int input_level;
+    int output_level;
     bool done;
+    Status status;
     bool in_progress;           // compaction request being processed?
     const InternalKey* begin;   // nullptr means beginning of key range
     const InternalKey* end;     // nullptr means end of key range
@@ -312,7 +561,12 @@ class DBImpl : public DB {
   int64_t volatile last_log_ts;
 
   // shall we disable deletion of obsolete files
-  bool disable_delete_obsolete_files_;
+  // if 0 the deletion is enabled.
+  // if non-zero, files will not be getting deleted
+  // This enables two different threads to call
+  // EnableFileDeletions() and DisableFileDeletions()
+  // without any synchronization
+  int disable_delete_obsolete_files_;
 
   // last time when DeleteObsoleteFiles was invoked
   uint64_t delete_obsolete_files_last_run_;
@@ -323,89 +577,19 @@ class DBImpl : public DB {
   // last time stats were dumped to LOG
   std::atomic<uint64_t> last_stats_dump_time_microsec_;
 
-  // These count the number of microseconds for which MakeRoomForWrite stalls.
-  uint64_t stall_level0_slowdown_;
-  uint64_t stall_memtable_compaction_;
-  uint64_t stall_level0_num_files_;
-  std::vector<uint64_t> stall_leveln_slowdown_;
-  uint64_t stall_level0_slowdown_count_;
-  uint64_t stall_memtable_compaction_count_;
-  uint64_t stall_level0_num_files_count_;
-  std::vector<uint64_t> stall_leveln_slowdown_count_;
-
-  // Time at which this instance was started.
-  const uint64_t started_at_;
+  // obsolete files will be deleted every this seconds if ttl deletion is
+  // enabled and archive size_limit is disabled.
+  uint64_t default_interval_to_delete_obsolete_WAL_;
 
   bool flush_on_destroy_; // Used when disableWAL is true.
 
-  // Per level compaction stats.  stats_[level] stores the stats for
-  // compactions that produced data for the specified "level".
-  struct CompactionStats {
-    uint64_t micros;
-
-    // Bytes read from level N during compaction between levels N and N+1
-    int64_t bytes_readn;
-
-    // Bytes read from level N+1 during compaction between levels N and N+1
-    int64_t bytes_readnp1;
-
-    // Total bytes written during compaction between levels N and N+1
-    int64_t bytes_written;
-
-    // Files read from level N during compaction between levels N and N+1
-    int     files_in_leveln;
-
-    // Files read from level N+1 during compaction between levels N and N+1
-    int     files_in_levelnp1;
-
-    // Files written during compaction between levels N and N+1
-    int     files_out_levelnp1;
-
-    // Number of compactions done
-    int     count;
-
-    CompactionStats() : micros(0), bytes_readn(0), bytes_readnp1(0),
-                        bytes_written(0), files_in_leveln(0),
-                        files_in_levelnp1(0), files_out_levelnp1(0),
-                        count(0) { }
-
-    void Add(const CompactionStats& c) {
-      this->micros += c.micros;
-      this->bytes_readn += c.bytes_readn;
-      this->bytes_readnp1 += c.bytes_readnp1;
-      this->bytes_written += c.bytes_written;
-      this->files_in_leveln += c.files_in_leveln;
-      this->files_in_levelnp1 += c.files_in_levelnp1;
-      this->files_out_levelnp1 += c.files_out_levelnp1;
-      this->count += 1;
-    }
-  };
-
-  std::vector<CompactionStats> stats_;
-
-  // Used to compute per-interval statistics
-  struct StatsSnapshot {
-    uint64_t bytes_read_;
-    uint64_t bytes_written_;
-    uint64_t bytes_new_;
-    double   seconds_up_;
-
-    StatsSnapshot() : bytes_read_(0), bytes_written_(0),
-                      bytes_new_(0), seconds_up_(0) {}
-  };
-
-  StatsSnapshot last_stats_;
-
   static const int KEEP_LOG_FILE_NUM = 1000;
+  static const uint64_t kNoTimeOut = std::numeric_limits<uint64_t>::max();
   std::string db_absolute_path_;
 
   // count of the number of contiguous delaying writes
   int delayed_writes_;
 
-  // store the last flushed sequence.
-  // Used by transaction log iterator.
-  SequenceNumber last_flushed_sequence_;
-
   // The options to access storage files
   const EnvOptions storage_options_;
 
@@ -415,6 +599,9 @@ class DBImpl : public DB {
   // Guard against multiple concurrent refitting
   bool refitting_level_;
 
+  // Indicate DB was opened successfully
+  bool opened_successfully_;
+
   // No copying allowed
   DBImpl(const DBImpl&);
   void operator=(const DBImpl&);
@@ -429,11 +616,23 @@ class DBImpl : public DB {
     std::vector<SequenceNumber>& snapshots,
     SequenceNumber* prev_snapshot);
 
+  // Background threads call this function, which is just a wrapper around
+  // the cfd->InstallSuperVersion() function. Background threads carry
+  // deletion_state which can have new_superversion already allocated.
+  void InstallSuperVersion(ColumnFamilyData* cfd,
+                           DeletionState& deletion_state);
+
+#ifndef ROCKSDB_LITE
+  using DB::GetPropertiesOfAllTables;
+  virtual Status GetPropertiesOfAllTables(ColumnFamilyHandle* column_family,
+                                          TablePropertiesCollection* props)
+      override;
+#endif  // ROCKSDB_LITE
+
   // Function that Get and KeyMayExist call with no_io true or false
   // Note: 'value_found' from KeyMayExist propagates here
-  Status GetImpl(const ReadOptions& options,
-                 const Slice& key,
-                 std::string* value,
+  Status GetImpl(const ReadOptions& options, ColumnFamilyHandle* column_family,
+                 const Slice& key, std::string* value,
                  bool* value_found = nullptr);
 };
 
@@ -443,7 +642,6 @@ extern Options SanitizeOptions(const std::string& db,
                                const InternalKeyComparator* icmp,
                                const InternalFilterPolicy* ipolicy,
                                const Options& src);
+extern DBOptions SanitizeOptions(const std::string& db, const DBOptions& src);
 
 }  // namespace rocksdb
-
-#endif  // STORAGE_LEVELDB_DB_DB_IMPL_H_

db/db_impl_debug.cc

@@ -0,0 +1,133 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#ifndef ROCKSDB_LITE
+
+#include "db/db_impl.h"
+
+namespace rocksdb {
+
+void DBImpl::TEST_PurgeObsoleteteWAL() { PurgeObsoleteWALFiles(); }
+
+uint64_t DBImpl::TEST_GetLevel0TotalSize() {
+  MutexLock l(&mutex_);
+  return default_cf_handle_->cfd()->current()->NumLevelBytes(0);
+}
+
+Iterator* DBImpl::TEST_NewInternalIterator(ColumnFamilyHandle* column_family) {
+  ColumnFamilyData* cfd;
+  if (column_family == nullptr) {
+    cfd = default_cf_handle_->cfd();
+  } else {
+    auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
+    cfd = cfh->cfd();
+  }
+
+  mutex_.Lock();
+  SuperVersion* super_version = cfd->GetSuperVersion()->Ref();
+  mutex_.Unlock();
+  ReadOptions roptions;
+  return NewInternalIterator(roptions, cfd, super_version);
+}
+
+int64_t DBImpl::TEST_MaxNextLevelOverlappingBytes(
+    ColumnFamilyHandle* column_family) {
+  ColumnFamilyData* cfd;
+  if (column_family == nullptr) {
+    cfd = default_cf_handle_->cfd();
+  } else {
+    auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
+    cfd = cfh->cfd();
+  }
+  MutexLock l(&mutex_);
+  return cfd->current()->MaxNextLevelOverlappingBytes();
+}
+
+void DBImpl::TEST_GetFilesMetaData(
+    ColumnFamilyHandle* column_family,
+    std::vector<std::vector<FileMetaData>>* metadata) {
+  auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
+  auto cfd = cfh->cfd();
+  MutexLock l(&mutex_);
+  metadata->resize(NumberLevels());
+  for (int level = 0; level < NumberLevels(); level++) {
+    const std::vector<FileMetaData*>& files = cfd->current()->files_[level];
+
+    (*metadata)[level].clear();
+    for (const auto& f : files) {
+      (*metadata)[level].push_back(*f);
+    }
+  }
+}
+
+uint64_t DBImpl::TEST_Current_Manifest_FileNo() {
+  return versions_->ManifestFileNumber();
+}
+
+Status DBImpl::TEST_CompactRange(int level, const Slice* begin,
+                                 const Slice* end,
+                                 ColumnFamilyHandle* column_family) {
+  ColumnFamilyData* cfd;
+  if (column_family == nullptr) {
+    cfd = default_cf_handle_->cfd();
+  } else {
+    auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
+    cfd = cfh->cfd();
+  }
+  int output_level =
+      (cfd->options()->compaction_style == kCompactionStyleUniversal ||
+       cfd->options()->compaction_style == kCompactionStyleFIFO)
+          ? level
+          : level + 1;
+  return RunManualCompaction(cfd, level, output_level, begin, end);
+}
+
+Status DBImpl::TEST_FlushMemTable(bool wait) {
+  FlushOptions fo;
+  fo.wait = wait;
+  return FlushMemTable(default_cf_handle_->cfd(), fo);
+}
+
+Status DBImpl::TEST_WaitForFlushMemTable(ColumnFamilyHandle* column_family) {
+  ColumnFamilyData* cfd;
+  if (column_family == nullptr) {
+    cfd = default_cf_handle_->cfd();
+  } else {
+    auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
+    cfd = cfh->cfd();
+  }
+  return WaitForFlushMemTable(cfd);
+}
+
+Status DBImpl::TEST_WaitForCompact() {
+  // Wait until the compaction completes
+
+  // TODO: a bug here. This function actually does not necessarily
+  // wait for compact. It actually waits for scheduled compaction
+  // OR flush to finish.
+
+  MutexLock l(&mutex_);
+  while ((bg_compaction_scheduled_ || bg_flush_scheduled_) && bg_error_.ok()) {
+    bg_cv_.Wait();
+  }
+  return bg_error_;
+}
+
+Status DBImpl::TEST_ReadFirstRecord(const WalFileType type,
+                                    const uint64_t number,
+                                    SequenceNumber* sequence) {
+  return ReadFirstRecord(type, number, sequence);
+}
+
+Status DBImpl::TEST_ReadFirstLine(const std::string& fname,
+                                  SequenceNumber* sequence) {
+  return ReadFirstLine(fname, sequence);
+}
+}  // namespace rocksdb
+#endif  // ROCKSDB_LITE

db/db_impl_readonly.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2012 Facebook. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -18,17 +23,18 @@
 #include "db/log_reader.h"
 #include "db/log_writer.h"
 #include "db/memtable.h"
+#include "db/merge_context.h"
 #include "db/table_cache.h"
 #include "db/version_set.h"
 #include "db/write_batch_internal.h"
 #include "rocksdb/db.h"
 #include "rocksdb/env.h"
 #include "rocksdb/status.h"
-#include "rocksdb/table_builder.h"
+#include "rocksdb/table.h"
+#include "rocksdb/merge_operator.h"
 #include "port/port.h"
 #include "table/block.h"
 #include "table/merger.h"
-#include "table/table.h"
 #include "table/two_level_iterator.h"
 #include "util/coding.h"
 #include "util/logging.h"
@@ -36,8 +42,8 @@
 
 namespace rocksdb {
 
-DBImplReadOnly::DBImplReadOnly(const Options& options,
-    const std::string& dbname)
+DBImplReadOnly::DBImplReadOnly(const DBOptions& options,
+                               const std::string& dbname)
     : DBImpl(options, dbname) {
   Log(options_.info_log, "Opening the db in read only mode");
 }
@@ -47,49 +53,100 @@ DBImplReadOnly::~DBImplReadOnly() {
 
 // Implementations of the DB interface
 Status DBImplReadOnly::Get(const ReadOptions& options,
-                   const Slice& key,
-                   std::string* value) {
+                           ColumnFamilyHandle* column_family, const Slice& key,
+                           std::string* value) {
   Status s;
-  MemTable* mem = GetMemTable();
-  Version* current = versions_->current();
   SequenceNumber snapshot = versions_->LastSequence();
-  std::deque<std::string> merge_operands;
+  auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
+  auto cfd = cfh->cfd();
+  SuperVersion* super_version = cfd->GetSuperVersion();
+  MergeContext merge_context;
   LookupKey lkey(key, snapshot);
-  if (mem->Get(lkey, value, &s, &merge_operands, options_)) {
+  if (super_version->mem->Get(lkey, value, &s, merge_context,
+                              *cfd->options())) {
   } else {
-    Version::GetStats stats;
-    current->Get(options, lkey, value, &s, &merge_operands, &stats, options_);
+    super_version->current->Get(options, lkey, value, &s, &merge_context);
   }
   return s;
 }
 
-Iterator* DBImplReadOnly::NewIterator(const ReadOptions& options) {
-  SequenceNumber latest_snapshot;
-  Iterator* internal_iter = NewInternalIterator(options, &latest_snapshot);
+Iterator* DBImplReadOnly::NewIterator(const ReadOptions& options,
+                                      ColumnFamilyHandle* column_family) {
+  auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
+  auto cfd = cfh->cfd();
+  SuperVersion* super_version = cfd->GetSuperVersion()->Ref();
+  SequenceNumber latest_snapshot = versions_->LastSequence();
+  Iterator* internal_iter = NewInternalIterator(options, cfd, super_version);
   return NewDBIterator(
-    &dbname_, env_, options_,  user_comparator(),internal_iter,
+      env_, *cfd->options(), cfd->user_comparator(), internal_iter,
       (options.snapshot != nullptr
-      ? reinterpret_cast<const SnapshotImpl*>(options.snapshot)->number_
-      : latest_snapshot));
+           ? reinterpret_cast<const SnapshotImpl*>(options.snapshot)->number_
+           : latest_snapshot));
 }
 
-
 Status DB::OpenForReadOnly(const Options& options, const std::string& dbname,
-                DB** dbptr, bool error_if_log_file_exist) {
+                           DB** dbptr, bool error_if_log_file_exist) {
   *dbptr = nullptr;
 
-  DBImplReadOnly* impl = new DBImplReadOnly(options, dbname);
+  DBOptions db_options(options);
+  ColumnFamilyOptions cf_options(options);
+  std::vector<ColumnFamilyDescriptor> column_families;
+  column_families.push_back(
+      ColumnFamilyDescriptor(kDefaultColumnFamilyName, cf_options));
+  std::vector<ColumnFamilyHandle*> handles;
+
+  Status s =
+      DB::OpenForReadOnly(db_options, dbname, column_families, &handles, dbptr);
+  if (s.ok()) {
+    assert(handles.size() == 1);
+    // i can delete the handle since DBImpl is always holding a
+    // reference to default column family
+    delete handles[0];
+  }
+  return s;
+}
+
+Status DB::OpenForReadOnly(
+    const DBOptions& db_options, const std::string& dbname,
+    const std::vector<ColumnFamilyDescriptor>& column_families,
+    std::vector<ColumnFamilyHandle*>* handles, DB** dbptr,
+    bool error_if_log_file_exist) {
+  *dbptr = nullptr;
+  handles->clear();
+
+  DBImplReadOnly* impl = new DBImplReadOnly(db_options, dbname);
   impl->mutex_.Lock();
-  VersionEdit edit(impl->NumberLevels());
-  Status s = impl->Recover(&edit, impl->GetMemTable(),
+  Status s = impl->Recover(column_families, true /* read only */,
                            error_if_log_file_exist);
+  if (s.ok()) {
+    // set column family handles
+    for (auto cf : column_families) {
+      auto cfd =
+          impl->versions_->GetColumnFamilySet()->GetColumnFamily(cf.name);
+      if (cfd == nullptr) {
+        s = Status::InvalidArgument("Column family not found: ", cf.name);
+        break;
+      }
+      handles->push_back(new ColumnFamilyHandleImpl(cfd, impl, &impl->mutex_));
+    }
+  }
+  if (s.ok()) {
+    for (auto cfd : *impl->versions_->GetColumnFamilySet()) {
+      delete cfd->InstallSuperVersion(new SuperVersion(), &impl->mutex_);
+    }
+  }
   impl->mutex_.Unlock();
   if (s.ok()) {
     *dbptr = impl;
   } else {
+    for (auto h : *handles) {
+      delete h;
+    }
+    handles->clear();
     delete impl;
   }
   return s;
 }
 
-}
+
+}   // namespace rocksdb

db/db_impl_readonly.h

@@ -1,14 +1,19 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2012 Facebook. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef STORAGE_LEVELDB_DB_DB_IMPL_READONLY_H_
-#define STORAGE_LEVELDB_DB_DB_IMPL_READONLY_H_
-
+#pragma once
 #include "db/db_impl.h"
 
 #include <deque>
 #include <set>
+#include <vector>
+#include <string>
 #include "db/dbformat.h"
 #include "db/log_writer.h"
 #include "db/snapshot.h"
@@ -17,65 +22,82 @@
 #include "port/port.h"
 #include "util/stats_logger.h"
 
-#ifdef USE_SCRIBE
-#include "scribe/scribe_logger.h"
-#endif
-
 namespace rocksdb {
 
 class DBImplReadOnly : public DBImpl {
-public:
-  DBImplReadOnly(const Options& options, const std::string& dbname);
- virtual ~DBImplReadOnly();
+ public:
+  DBImplReadOnly(const DBOptions& options, const std::string& dbname);
+  virtual ~DBImplReadOnly();
 
- // Implementations of the DB interface
- virtual Status Get(const ReadOptions& options,
-                    const Slice& key,
-                    std::string* value);
+  // Implementations of the DB interface
+  using DB::Get;
+  virtual Status Get(const ReadOptions& options,
+                     ColumnFamilyHandle* column_family, const Slice& key,
+                     std::string* value);
 
- // TODO: Implement ReadOnly MultiGet?
+  // TODO: Implement ReadOnly MultiGet?
 
- virtual Iterator* NewIterator(const ReadOptions&);
+  using DBImpl::NewIterator;
+  virtual Iterator* NewIterator(const ReadOptions&,
+                                ColumnFamilyHandle* column_family);
 
- virtual Status Put(const WriteOptions&, const Slice& key, const Slice& value) {
-   return Status::NotSupported("Not supported operation in read only mode.");
- }
- virtual Status Merge(const WriteOptions&, const Slice& key,
-                      const Slice& value) {
-   return Status::NotSupported("Not supported operation in read only mode.");
- }
- virtual Status Delete(const WriteOptions&, const Slice& key) {
-   return Status::NotSupported("Not supported operation in read only mode.");
- }
- virtual Status Write(const WriteOptions& options, WriteBatch* updates) {
-   return Status::NotSupported("Not supported operation in read only mode.");
- }
- virtual void CompactRange(const Slice* begin, const Slice* end,
-                           bool reduce_level = false, int target_level = -1) {
- }
- virtual Status DisableFileDeletions() {
-   return Status::NotSupported("Not supported operation in read only mode.");
- }
- virtual Status EnableFileDeletions() {
-   return Status::NotSupported("Not supported operation in read only mode.");
- }
- virtual Status GetLiveFiles(std::vector<std::string>&,
-                             uint64_t* manifest_file_size,
-                             bool flush_memtable = true) {
-   return Status::NotSupported("Not supported operation in read only mode.");
- }
- virtual Status Flush(const FlushOptions& options) {
-   return Status::NotSupported("Not supported operation in read only mode.");
- }
+  virtual Status NewIterators(
+      const ReadOptions& options,
+      const std::vector<ColumnFamilyHandle*>& column_family,
+      std::vector<Iterator*>* iterators) {
+   // TODO
+    return Status::NotSupported("Not supported yet.");
+  }
 
-private:
- friend class DB;
+  using DBImpl::Put;
+  virtual Status Put(const WriteOptions& options,
+                     ColumnFamilyHandle* column_family, const Slice& key,
+                     const Slice& value) {
+    return Status::NotSupported("Not supported operation in read only mode.");
+  }
+  using DBImpl::Merge;
+  virtual Status Merge(const WriteOptions& options,
+                       ColumnFamilyHandle* column_family, const Slice& key,
+                       const Slice& value) {
+    return Status::NotSupported("Not supported operation in read only mode.");
+  }
+  using DBImpl::Delete;
+  virtual Status Delete(const WriteOptions& options,
+                        ColumnFamilyHandle* column_family, const Slice& key) {
+    return Status::NotSupported("Not supported operation in read only mode.");
+  }
+  virtual Status Write(const WriteOptions& options, WriteBatch* updates) {
+    return Status::NotSupported("Not supported operation in read only mode.");
+  }
+  using DBImpl::CompactRange;
+  virtual Status CompactRange(ColumnFamilyHandle* column_family,
+                              const Slice* begin, const Slice* end,
+                              bool reduce_level = false,
+                              int target_level = -1) {
+    return Status::NotSupported("Not supported operation in read only mode.");
+  }
+  virtual Status DisableFileDeletions() {
+    return Status::NotSupported("Not supported operation in read only mode.");
+  }
+  virtual Status EnableFileDeletions(bool force) {
+    return Status::NotSupported("Not supported operation in read only mode.");
+  }
+  virtual Status GetLiveFiles(std::vector<std::string>&,
+                              uint64_t* manifest_file_size,
+                              bool flush_memtable = true) {
+    return Status::NotSupported("Not supported operation in read only mode.");
+  }
+  using DBImpl::Flush;
+  virtual Status Flush(const FlushOptions& options,
+                       ColumnFamilyHandle* column_family) {
+    return Status::NotSupported("Not supported operation in read only mode.");
+  }
 
- // No copying allowed
- DBImplReadOnly(const DBImplReadOnly&);
- void operator=(const DBImplReadOnly&);
+ private:
+  friend class DB;
+
+  // No copying allowed
+  DBImplReadOnly(const DBImplReadOnly&);
+  void operator=(const DBImplReadOnly&);
 };
-
 }
-
-#endif

db/db_iter.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -13,6 +18,7 @@
 #include "rocksdb/iterator.h"
 #include "rocksdb/merge_operator.h"
 #include "port/port.h"
+#include "util/arena.h"
 #include "util/logging.h"
 #include "util/mutexlock.h"
 #include "util/perf_context_imp.h"
@@ -32,8 +38,6 @@ static void DumpInternalIter(Iterator* iter) {
 }
 #endif
 
-namespace {
-
 // Memtables and sstables that make the DB representation contain
 // (userkey,seq,type) => uservalue entries.  DBIter
 // combines multiple entries for the same userkey found in the DB
@@ -52,11 +56,11 @@ class DBIter: public Iterator {
     kReverse
   };
 
-  DBIter(const std::string* dbname, Env* env, const Options& options,
-         const Comparator* cmp, Iterator* iter, SequenceNumber s)
-      : dbname_(dbname),
+  DBIter(Env* env, const Options& options, const Comparator* cmp,
+         Iterator* iter, SequenceNumber s, bool arena_mode)
+      : arena_mode_(arena_mode),
         env_(env),
-        logger_(options.info_log),
+        logger_(options.info_log.get()),
         user_comparator_(cmp),
         user_merge_operator_(options.merge_operator.get()),
         iter_(iter),
@@ -64,18 +68,26 @@ class DBIter: public Iterator {
         direction_(kForward),
         valid_(false),
         current_entry_is_merged_(false),
-        statistics_(options.statistics) {
+        statistics_(options.statistics.get()) {
     RecordTick(statistics_, NO_ITERATORS, 1);
     max_skip_ = options.max_sequential_skip_in_iterations;
   }
   virtual ~DBIter() {
     RecordTick(statistics_, NO_ITERATORS, -1);
-    delete iter_;
+    if (!arena_mode_) {
+      delete iter_;
+    } else {
+      iter_->~Iterator();
+    }
+  }
+  virtual void SetIter(Iterator* iter) {
+    assert(iter_ == nullptr);
+    iter_ = iter;
   }
   virtual bool Valid() const { return valid_; }
   virtual Slice key() const {
     assert(valid_);
-    return saved_key_;
+    return saved_key_.GetKey();
   }
   virtual Slice value() const {
     assert(valid_);
@@ -97,15 +109,12 @@ class DBIter: public Iterator {
   virtual void SeekToLast();
 
  private:
-  void FindNextUserEntry(bool skipping);
+  inline void FindNextUserEntry(bool skipping);
+  void FindNextUserEntryInternal(bool skipping);
   void FindPrevUserEntry();
   bool ParseKey(ParsedInternalKey* key);
   void MergeValuesNewToOld();
 
-  inline void SaveKey(const Slice& k, std::string* dst) {
-    dst->assign(k.data(), k.size());
-  }
-
   inline void ClearSavedValue() {
     if (saved_value_.capacity() > 1048576) {
       std::string empty;
@@ -115,22 +124,21 @@ class DBIter: public Iterator {
     }
   }
 
-  const std::string* const dbname_;
+  bool arena_mode_;
   Env* const env_;
-  shared_ptr<Logger> logger_;
+  Logger* logger_;
   const Comparator* const user_comparator_;
   const MergeOperator* const user_merge_operator_;
-  Iterator* const iter_;
+  Iterator* iter_;
   SequenceNumber const sequence_;
 
   Status status_;
-  std::string saved_key_;     // == current key when direction_==kReverse
+  IterKey saved_key_;   // == current key when direction_==kReverse
   std::string saved_value_;   // == current raw value when direction_==kReverse
-  std::string skip_key_;
   Direction direction_;
   bool valid_;
   bool current_entry_is_merged_;
-  std::shared_ptr<Statistics> statistics_;
+  Statistics* statistics_;
   uint64_t max_skip_;
 
   // No copying allowed
@@ -164,7 +172,7 @@ void DBIter::Next() {
     }
     if (!iter_->Valid()) {
       valid_ = false;
-      saved_key_.clear();
+      saved_key_.Clear();
       return;
     }
   }
@@ -186,7 +194,14 @@ void DBIter::Next() {
 //
 // NOTE: In between, saved_key_ can point to a user key that has
 //       a delete marker
-void DBIter::FindNextUserEntry(bool skipping) {
+inline void DBIter::FindNextUserEntry(bool skipping) {
+  PERF_TIMER_AUTO(find_next_user_entry_time);
+  FindNextUserEntryInternal(skipping);
+  PERF_TIMER_STOP(find_next_user_entry_time);
+}
+
+// Actual implementation of DBIter::FindNextUserEntry()
+void DBIter::FindNextUserEntryInternal(bool skipping) {
   // Loop until we hit an acceptable entry to yield
   assert(iter_->Valid());
   assert(direction_ == kForward);
@@ -196,32 +211,32 @@ void DBIter::FindNextUserEntry(bool skipping) {
     ParsedInternalKey ikey;
     if (ParseKey(&ikey) && ikey.sequence <= sequence_) {
       if (skipping &&
-          user_comparator_->Compare(ikey.user_key, saved_key_) <= 0) {
+          user_comparator_->Compare(ikey.user_key, saved_key_.GetKey()) <= 0) {
         num_skipped++; // skip this entry
-        BumpPerfCount(&perf_context.internal_key_skipped_count);
+        PERF_COUNTER_ADD(internal_key_skipped_count, 1);
       } else {
         skipping = false;
         switch (ikey.type) {
           case kTypeDeletion:
             // Arrange to skip all upcoming entries for this key since
             // they are hidden by this deletion.
-            SaveKey(ikey.user_key, &saved_key_);
+            saved_key_.SetKey(ikey.user_key);
             skipping = true;
             num_skipped = 0;
-            BumpPerfCount(&perf_context.internal_delete_skipped_count);
+            PERF_COUNTER_ADD(internal_delete_skipped_count, 1);
             break;
           case kTypeValue:
             valid_ = true;
-            SaveKey(ikey.user_key, &saved_key_);
+            saved_key_.SetKey(ikey.user_key);
             return;
           case kTypeMerge:
             // By now, we are sure the current ikey is going to yield a value
-            SaveKey(ikey.user_key, &saved_key_);
+            saved_key_.SetKey(ikey.user_key);
             current_entry_is_merged_ = true;
             valid_ = true;
             MergeValuesNewToOld();  // Go to a different state machine
             return;
-          case kTypeLogData:
+          default:
             assert(false);
             break;
         }
@@ -234,8 +249,8 @@ void DBIter::FindNextUserEntry(bool skipping) {
     if (skipping && num_skipped > max_skip_) {
       num_skipped = 0;
       std::string last_key;
-      AppendInternalKey(&last_key,
-        ParsedInternalKey(Slice(saved_key_), 0, kValueTypeForSeek));
+      AppendInternalKey(&last_key, ParsedInternalKey(saved_key_.GetKey(), 0,
+                                                     kValueTypeForSeek));
       iter_->Seek(last_key);
       RecordTick(statistics_, NUMBER_OF_RESEEKS_IN_ITERATION);
     } else {
@@ -270,7 +285,7 @@ void DBIter::MergeValuesNewToOld() {
       continue;
     }
 
-    if (user_comparator_->Compare(ikey.user_key, saved_key_) != 0) {
+    if (user_comparator_->Compare(ikey.user_key, saved_key_.GetKey()) != 0) {
       // hit the next user key, stop right here
       break;
     }
@@ -288,7 +303,7 @@ void DBIter::MergeValuesNewToOld() {
       // ignore corruption if there is any.
       const Slice value = iter_->value();
       user_merge_operator_->FullMerge(ikey.user_key, &value, operands,
-                                      &saved_value_, logger_.get());
+                                      &saved_value_, logger_);
       // iter_ is positioned after put
       iter_->Next();
       return;
@@ -299,21 +314,6 @@ void DBIter::MergeValuesNewToOld() {
       // when complete, add result to operands and continue.
       const Slice& value = iter_->value();
       operands.push_front(value.ToString());
-      while(operands.size() >= 2) {
-        // Call user associative-merge until it returns false
-        if (user_merge_operator_->PartialMerge(ikey.user_key,
-                                               Slice(operands[0]),
-                                               Slice(operands[1]),
-                                               &merge_result,
-                                               logger_.get())) {
-          operands.pop_front();
-          swap(operands.front(), merge_result);
-        } else {
-          // Associative merge returns false ==> stack the operands
-          break;
-        }
-      }
-
     }
   }
 
@@ -321,8 +321,8 @@ void DBIter::MergeValuesNewToOld() {
   // a deletion marker.
   // feed null as the existing value to the merge operator, such that
   // client can differentiate this scenario and do things accordingly.
-  user_merge_operator_->FullMerge(saved_key_, nullptr, operands,
-                                  &saved_value_, logger_.get());
+  user_merge_operator_->FullMerge(saved_key_.GetKey(), nullptr, operands,
+                                  &saved_value_, logger_);
 }
 
 void DBIter::Prev() {
@@ -340,17 +340,17 @@ void DBIter::Prev() {
     // iter_ is pointing at the current entry.  Scan backwards until
     // the key changes so we can use the normal reverse scanning code.
     assert(iter_->Valid());  // Otherwise valid_ would have been false
-    SaveKey(ExtractUserKey(iter_->key()), &saved_key_);
+    saved_key_.SetKey(ExtractUserKey(iter_->key()));
     while (true) {
       iter_->Prev();
       if (!iter_->Valid()) {
         valid_ = false;
-        saved_key_.clear();
+        saved_key_.Clear();
         ClearSavedValue();
         return;
       }
       if (user_comparator_->Compare(ExtractUserKey(iter_->key()),
-                                    saved_key_) < 0) {
+                                    saved_key_.GetKey()) < 0) {
         break;
       }
     }
@@ -365,40 +365,46 @@ void DBIter::FindPrevUserEntry() {
   uint64_t num_skipped = 0;
 
   ValueType value_type = kTypeDeletion;
+  bool saved_key_valid = true;
   if (iter_->Valid()) {
     do {
       ParsedInternalKey ikey;
       if (ParseKey(&ikey) && ikey.sequence <= sequence_) {
         if ((value_type != kTypeDeletion) &&
-            user_comparator_->Compare(ikey.user_key, saved_key_) < 0) {
+            user_comparator_->Compare(ikey.user_key, saved_key_.GetKey()) < 0) {
           // We encountered a non-deleted value in entries for previous keys,
           break;
         }
         value_type = ikey.type;
         if (value_type == kTypeDeletion) {
-          saved_key_.clear();
+          saved_key_.Clear();
           ClearSavedValue();
+          saved_key_valid = false;
         } else {
           Slice raw_value = iter_->value();
           if (saved_value_.capacity() > raw_value.size() + 1048576) {
             std::string empty;
             swap(empty, saved_value_);
           }
-          SaveKey(ExtractUserKey(iter_->key()), &saved_key_);
+          saved_key_.SetKey(ExtractUserKey(iter_->key()));
           saved_value_.assign(raw_value.data(), raw_value.size());
         }
+      } else {
+        // In the case of ikey.sequence > sequence_, we might have already
+        // iterated to a different user key.
+        saved_key_valid = false;
       }
       num_skipped++;
       // If we have sequentially iterated via numerous keys and still not
       // found the prev user-key, then it is better to seek so that we can
       // avoid too many key comparisons. We seek to the first occurence of
       // our current key by looking for max sequence number.
-      if (num_skipped > max_skip_) {
+      if (saved_key_valid && num_skipped > max_skip_) {
         num_skipped = 0;
         std::string last_key;
-        AppendInternalKey(&last_key,
-          ParsedInternalKey(Slice(saved_key_), kMaxSequenceNumber,
-                            kValueTypeForSeek));
+        AppendInternalKey(&last_key, ParsedInternalKey(saved_key_.GetKey(),
+                                                       kMaxSequenceNumber,
+                                                       kValueTypeForSeek));
         iter_->Seek(last_key);
         RecordTick(statistics_, NUMBER_OF_RESEEKS_IN_ITERATION);
       } else {
@@ -410,7 +416,7 @@ void DBIter::FindPrevUserEntry() {
   if (value_type == kTypeDeletion) {
     // End
     valid_ = false;
-    saved_key_.clear();
+    saved_key_.Clear();
     ClearSavedValue();
     direction_ = kForward;
   } else {
@@ -419,13 +425,15 @@ void DBIter::FindPrevUserEntry() {
 }
 
 void DBIter::Seek(const Slice& target) {
-  direction_ = kForward;
-  ClearSavedValue();
-  saved_key_.clear();
-  AppendInternalKey(
-      &saved_key_, ParsedInternalKey(target, sequence_, kValueTypeForSeek));
-  iter_->Seek(saved_key_);
+  saved_key_.Clear();
+  // now savved_key is used to store internal key.
+  saved_key_.SetInternalKey(target, sequence_);
+  PERF_TIMER_AUTO(seek_internal_seek_time);
+  iter_->Seek(saved_key_.GetKey());
+  PERF_TIMER_STOP(seek_internal_seek_time);
   if (iter_->Valid()) {
+    direction_ = kForward;
+    ClearSavedValue();
     FindNextUserEntry(false /*not skipping */);
   } else {
     valid_ = false;
@@ -435,7 +443,9 @@ void DBIter::Seek(const Slice& target) {
 void DBIter::SeekToFirst() {
   direction_ = kForward;
   ClearSavedValue();
+  PERF_TIMER_AUTO(seek_internal_seek_time);
   iter_->SeekToFirst();
+  PERF_TIMER_STOP(seek_internal_seek_time);
   if (iter_->Valid()) {
     FindNextUserEntry(false /* not skipping */);
   } else {
@@ -454,21 +464,54 @@ void DBIter::SeekToLast() {
 
   direction_ = kReverse;
   ClearSavedValue();
+  PERF_TIMER_AUTO(seek_internal_seek_time);
   iter_->SeekToLast();
+  PERF_TIMER_STOP(seek_internal_seek_time);
   FindPrevUserEntry();
 }
 
-}  // anonymous namespace
+Iterator* NewDBIterator(Env* env, const Options& options,
+                        const Comparator* user_key_comparator,
+                        Iterator* internal_iter,
+                        const SequenceNumber& sequence) {
+  return new DBIter(env, options, user_key_comparator, internal_iter, sequence,
+                    false);
+}
 
-Iterator* NewDBIterator(
-    const std::string* dbname,
-    Env* env,
-    const Options& options,
-    const Comparator *user_key_comparator,
-    Iterator* internal_iter,
+ArenaWrappedDBIter::~ArenaWrappedDBIter() { db_iter_->~DBIter(); }
+
+void ArenaWrappedDBIter::SetDBIter(DBIter* iter) { db_iter_ = iter; }
+
+void ArenaWrappedDBIter::SetIterUnderDBIter(Iterator* iter) {
+  static_cast<DBIter*>(db_iter_)->SetIter(iter);
+}
+
+inline bool ArenaWrappedDBIter::Valid() const { return db_iter_->Valid(); }
+inline void ArenaWrappedDBIter::SeekToFirst() { db_iter_->SeekToFirst(); }
+inline void ArenaWrappedDBIter::SeekToLast() { db_iter_->SeekToLast(); }
+inline void ArenaWrappedDBIter::Seek(const Slice& target) {
+  db_iter_->Seek(target);
+}
+inline void ArenaWrappedDBIter::Next() { db_iter_->Next(); }
+inline void ArenaWrappedDBIter::Prev() { db_iter_->Prev(); }
+inline Slice ArenaWrappedDBIter::key() const { return db_iter_->key(); }
+inline Slice ArenaWrappedDBIter::value() const { return db_iter_->value(); }
+inline Status ArenaWrappedDBIter::status() const { return db_iter_->status(); }
+void ArenaWrappedDBIter::RegisterCleanup(CleanupFunction function, void* arg1,
+                                         void* arg2) {
+  db_iter_->RegisterCleanup(function, arg1, arg2);
+}
+
+ArenaWrappedDBIter* NewArenaWrappedDbIterator(
+    Env* env, const Options& options, const Comparator* user_key_comparator,
     const SequenceNumber& sequence) {
-  return new DBIter(dbname, env, options, user_key_comparator,
-                    internal_iter, sequence);
+  ArenaWrappedDBIter* iter = new ArenaWrappedDBIter();
+  Arena* arena = iter->GetArena();
+  auto mem = arena->AllocateAligned(sizeof(DBIter));
+  DBIter* db_iter = new (mem)
+      DBIter(env, options, user_key_comparator, nullptr, sequence, true);
+  iter->SetDBIter(db_iter);
+  return iter;
 }
 
 }  // namespace rocksdb

db/db_iter.h

@@ -1,27 +1,73 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
-#ifndef STORAGE_LEVELDB_DB_DB_ITER_H_
-#define STORAGE_LEVELDB_DB_DB_ITER_H_
-
+#pragma once
 #include <stdint.h>
 #include "rocksdb/db.h"
 #include "db/dbformat.h"
+#include "util/arena.h"
+#include "util/autovector.h"
 
 namespace rocksdb {
 
+class Arena;
+class DBIter;
+
 // Return a new iterator that converts internal keys (yielded by
 // "*internal_iter") that were live at the specified "sequence" number
 // into appropriate user keys.
 extern Iterator* NewDBIterator(
-    const std::string* dbname,
     Env* env,
     const Options& options,
     const Comparator *user_key_comparator,
     Iterator* internal_iter,
     const SequenceNumber& sequence);
 
-}  // namespace rocksdb
+// A wrapper iterator which wraps DB Iterator and the arena, with which the DB
+// iterator is supposed be allocated. This class is used as an entry point of
+// a iterator hierarchy whose memory can be allocated inline. In that way,
+// accessing the iterator tree can be more cache friendly. It is also faster
+// to allocate.
+class ArenaWrappedDBIter : public Iterator {
+ public:
+  virtual ~ArenaWrappedDBIter();
 
-#endif  // STORAGE_LEVELDB_DB_DB_ITER_H_
+  // Get the arena to be used to allocate memory for DBIter to be wrapped,
+  // as well as child iterators in it.
+  virtual Arena* GetArena() { return &arena_; }
+
+  // Set the DB Iterator to be wrapped
+
+  virtual void SetDBIter(DBIter* iter);
+
+  // Set the internal iterator wrapped inside the DB Iterator. Usually it is
+  // a merging iterator.
+  virtual void SetIterUnderDBIter(Iterator* iter);
+  virtual bool Valid() const override;
+  virtual void SeekToFirst() override;
+  virtual void SeekToLast() override;
+  virtual void Seek(const Slice& target) override;
+  virtual void Next() override;
+  virtual void Prev() override;
+  virtual Slice key() const override;
+  virtual Slice value() const override;
+  virtual Status status() const override;
+  void RegisterCleanup(CleanupFunction function, void* arg1, void* arg2);
+
+ private:
+  DBIter* db_iter_;
+  Arena arena_;
+};
+
+// Generate the arena wrapped iterator class.
+extern ArenaWrappedDBIter* NewArenaWrappedDbIterator(
+    Env* env, const Options& options, const Comparator* user_key_comparator,
+    const SequenceNumber& sequence);
+
+}  // namespace rocksdb

db/db_statistics.h

@@ -1,64 +0,0 @@
-// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file. See the AUTHORS file for names of contributors.
-
-#ifndef LEVELDB_STORAGE_DB_DB_STATISTICS_H_
-#define LEVELDB_STORAGE_DB_DB_STATISTICS_H_
-
-#include <cassert>
-#include <stdlib.h>
-#include <vector>
-#include <memory>
-
-#include "rocksdb/statistics.h"
-#include "util/histogram.h"
-#include "port/port.h"
-#include "util/mutexlock.h"
-
-
-namespace rocksdb {
-
-class DBStatistics: public Statistics {
- public:
-  DBStatistics() : allTickers_(TICKER_ENUM_MAX),
-                   allHistograms_(HISTOGRAM_ENUM_MAX) { }
-
-  virtual ~DBStatistics() {}
-
-  virtual long getTickerCount(Tickers tickerType) {
-    assert(tickerType < TICKER_ENUM_MAX);
-    return allTickers_[tickerType].getCount();
-  }
-
-  virtual void setTickerCount(Tickers tickerType, uint64_t count) {
-    assert(tickerType < TICKER_ENUM_MAX);
-    allTickers_[tickerType].setTickerCount(count);
-  }
-
-  virtual void recordTick(Tickers tickerType, uint64_t count) {
-    assert(tickerType < TICKER_ENUM_MAX);
-    allTickers_[tickerType].recordTick(count);
-  }
-
-  virtual void measureTime(Histograms histogramType, uint64_t value) {
-    assert(histogramType < HISTOGRAM_ENUM_MAX);
-    allHistograms_[histogramType].Add(value);
-  }
-
-  virtual void histogramData(Histograms histogramType,
-                             HistogramData * const data) {
-    assert(histogramType < HISTOGRAM_ENUM_MAX);
-    allHistograms_[histogramType].Data(data);
-  }
-
-  std::vector<Ticker> allTickers_;
-  std::vector<HistogramImpl> allHistograms_;
-};
-
-std::shared_ptr<Statistics> CreateDBStatistics() {
-  return std::make_shared<DBStatistics>();
-}
-
-} // namespace rocksdb
-
-#endif // LEVELDB_STORAGE_DB_DB_STATISTICS_H_

db/db_stats_logger.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -15,7 +20,8 @@
 namespace rocksdb {
 
 void DBImpl::MaybeScheduleLogDBDeployStats() {
-
+// we did say maybe
+#ifndef ROCKSDB_LITE
   // There is a lock in the actual logger.
   if (!logger_ || options_.db_stats_log_interval < 0
       || host_name_.empty()) {
@@ -60,13 +66,14 @@ void DBImpl::LogDBDeployStats() {
 
   uint64_t file_total_size = 0;
   uint32_t file_total_num = 0;
-  for (int i = 0; i < versions_->NumberLevels(); i++) {
-    file_total_num += versions_->NumLevelFiles(i);
-    file_total_size += versions_->NumLevelBytes(i);
+  Version* current = default_cf_handle_->cfd()->current();
+  for (int i = 0; i < current->NumberLevels(); i++) {
+    file_total_num += current->NumLevelFiles(i);
+    file_total_size += current->NumLevelBytes(i);
   }
 
-  VersionSet::LevelSummaryStorage scratch;
-  const char* file_num_summary = versions_->LevelSummary(&scratch);
+  Version::LevelSummaryStorage scratch;
+  const char* file_num_summary = current->LevelSummary(&scratch);
   std::string file_num_per_level(file_num_summary);
   std::string data_size_per_level(file_num_summary);
 
@@ -83,6 +90,6 @@ void DBImpl::LogDBDeployStats() {
   bg_logstats_scheduled_ = false;
   bg_cv_.SignalAll();
   mutex_.Unlock();
+#endif
 }
-
 }

db/dbformat.cc

@@ -1,16 +1,21 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
+#include "db/dbformat.h"
 
 #include <stdio.h>
-#include "db/dbformat.h"
 #include "port/port.h"
 #include "util/coding.h"
 #include "util/perf_context_imp.h"
 
 namespace rocksdb {
 
-static uint64_t PackSequenceAndType(uint64_t seq, ValueType t) {
+uint64_t PackSequenceAndType(uint64_t seq, ValueType t) {
   assert(seq <= kMaxSequenceNumber);
   assert(t <= kValueTypeForSeek);
   return (seq << 8) | t;
@@ -54,7 +59,7 @@ int InternalKeyComparator::Compare(const Slice& akey, const Slice& bkey) const {
   //    decreasing sequence number
   //    decreasing type (though sequence# should be enough to disambiguate)
   int r = user_comparator_->Compare(ExtractUserKey(akey), ExtractUserKey(bkey));
-  BumpPerfCount(&perf_context.user_key_comparison_count);
+  PERF_COUNTER_ADD(user_key_comparison_count, 1);
   if (r == 0) {
     const uint64_t anum = DecodeFixed64(akey.data() + akey.size() - 8);
     const uint64_t bnum = DecodeFixed64(bkey.data() + bkey.size() - 8);
@@ -67,6 +72,28 @@ int InternalKeyComparator::Compare(const Slice& akey, const Slice& bkey) const {
   return r;
 }
 
+int InternalKeyComparator::Compare(const ParsedInternalKey& a,
+                                   const ParsedInternalKey& b) const {
+  // Order by:
+  //    increasing user key (according to user-supplied comparator)
+  //    decreasing sequence number
+  //    decreasing type (though sequence# should be enough to disambiguate)
+  int r = user_comparator_->Compare(a.user_key, b.user_key);
+  PERF_COUNTER_ADD(user_key_comparison_count, 1);
+  if (r == 0) {
+    if (a.sequence > b.sequence) {
+      r = -1;
+    } else if (a.sequence < b.sequence) {
+      r = +1;
+    } else if (a.type > b.type) {
+      r = -1;
+    } else if (a.type < b.type) {
+      r = +1;
+    }
+  }
+  return r;
+}
+
 void InternalKeyComparator::FindShortestSeparator(
       std::string* start,
       const Slice& limit) const {

db/dbformat.h

@@ -1,16 +1,20 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
-#ifndef STORAGE_LEVELDB_DB_FORMAT_H_
-#define STORAGE_LEVELDB_DB_FORMAT_H_
-
+#pragma once
 #include <stdio.h>
 #include "rocksdb/comparator.h"
 #include "rocksdb/db.h"
 #include "rocksdb/filter_policy.h"
 #include "rocksdb/slice.h"
-#include "rocksdb/table_builder.h"
+#include "rocksdb/slice_transform.h"
+#include "rocksdb/table.h"
 #include "rocksdb/types.h"
 #include "util/coding.h"
 #include "util/logging.h"
@@ -22,12 +26,21 @@ class InternalKey;
 // Value types encoded as the last component of internal keys.
 // DO NOT CHANGE THESE ENUM VALUES: they are embedded in the on-disk
 // data structures.
-enum ValueType {
+// The highest bit of the value type needs to be reserved to SST tables
+// for them to do more flexible encoding.
+enum ValueType : unsigned char {
   kTypeDeletion = 0x0,
   kTypeValue = 0x1,
   kTypeMerge = 0x2,
-  kTypeLogData = 0x3
+  // Following types are used only in write ahead logs. They are not used in
+  // memtables or sst files:
+  kTypeLogData = 0x3,
+  kTypeColumnFamilyDeletion = 0x4,
+  kTypeColumnFamilyValue = 0x5,
+  kTypeColumnFamilyMerge = 0x6,
+  kMaxValue = 0x7F
 };
+
 // kValueTypeForSeek defines the ValueType that should be passed when
 // constructing a ParsedInternalKey object for seeking to a particular
 // sequence number (since we sort sequence numbers in decreasing order
@@ -57,6 +70,8 @@ inline size_t InternalKeyEncodingLength(const ParsedInternalKey& key) {
   return key.user_key.size() + 8;
 }
 
+extern uint64_t PackSequenceAndType(uint64_t seq, ValueType t);
+
 // Append the serialization of "key" to *result.
 extern void AppendInternalKey(std::string* result,
                               const ParsedInternalKey& key);
@@ -90,9 +105,10 @@ class InternalKeyComparator : public Comparator {
   std::string name_;
  public:
   explicit InternalKeyComparator(const Comparator* c) : user_comparator_(c),
-    name_("leveldb.InternalKeyComparator:" +
+    name_("rocksdb.InternalKeyComparator:" +
           std::string(user_comparator_->Name())) {
   }
+  virtual ~InternalKeyComparator() {}
 
   virtual const char* Name() const;
   virtual int Compare(const Slice& a, const Slice& b) const;
@@ -104,6 +120,7 @@ class InternalKeyComparator : public Comparator {
   const Comparator* user_comparator() const { return user_comparator_; }
 
   int Compare(const InternalKey& a, const InternalKey& b) const;
+  int Compare(const ParsedInternalKey& a, const ParsedInternalKey& b) const;
 };
 
 // Filter policy wrapper that converts from internal keys to user keys
@@ -129,6 +146,11 @@ class InternalKey {
     AppendInternalKey(&rep_, ParsedInternalKey(user_key, s, t));
   }
 
+  bool Valid() const {
+    ParsedInternalKey parsed;
+    return ParseInternalKey(Slice(rep_), &parsed);
+  }
+
   void DecodeFrom(const Slice& s) { rep_.assign(s.data(), s.size()); }
   Slice Encode() const {
     assert(!rep_.empty());
@@ -160,6 +182,7 @@ inline bool ParseInternalKey(const Slice& internal_key,
   unsigned char c = num & 0xff;
   result->sequence = num >> 8;
   result->type = static_cast<ValueType>(c);
+  assert(result->type <= ValueType::kMaxValue);
   result->user_key = Slice(internal_key.data(), n - 8);
   return (c <= static_cast<unsigned char>(kValueTypeForSeek));
 }
@@ -223,6 +246,128 @@ inline LookupKey::~LookupKey() {
   if (start_ != space_) delete[] start_;
 }
 
-}  // namespace rocksdb
+class IterKey {
+ public:
+  IterKey() : key_(space_), buf_size_(sizeof(space_)), key_size_(0) {}
 
-#endif  // STORAGE_LEVELDB_DB_FORMAT_H_
+  ~IterKey() { ResetBuffer(); }
+
+  Slice GetKey() const { return Slice(key_, key_size_); }
+
+  void Clear() { key_size_ = 0; }
+
+  void SetKey(const Slice& key) {
+    size_t size = key.size();
+    EnlargeBufferIfNeeded(size);
+    memcpy(key_, key.data(), size);
+    key_size_ = size;
+  }
+
+  void SetInternalKey(const Slice& key_prefix, const Slice& user_key,
+                      SequenceNumber s,
+                      ValueType value_type = kValueTypeForSeek) {
+    size_t psize = key_prefix.size();
+    size_t usize = user_key.size();
+    EnlargeBufferIfNeeded(psize + usize + sizeof(uint64_t));
+    if (psize > 0) {
+      memcpy(key_, key_prefix.data(), psize);
+    }
+    memcpy(key_ + psize, user_key.data(), usize);
+    EncodeFixed64(key_ + usize + psize, PackSequenceAndType(s, value_type));
+    key_size_ = psize + usize + sizeof(uint64_t);
+  }
+
+  void SetInternalKey(const Slice& user_key, SequenceNumber s,
+                      ValueType value_type = kValueTypeForSeek) {
+    SetInternalKey(Slice(), user_key, s, value_type);
+  }
+
+  void Reserve(size_t size) {
+    EnlargeBufferIfNeeded(size);
+    key_size_ = size;
+  }
+
+  void SetInternalKey(const ParsedInternalKey& parsed_key) {
+    SetInternalKey(Slice(), parsed_key);
+  }
+
+  void SetInternalKey(const Slice& key_prefix,
+                      const ParsedInternalKey& parsed_key_suffix) {
+    SetInternalKey(key_prefix, parsed_key_suffix.user_key,
+                   parsed_key_suffix.sequence, parsed_key_suffix.type);
+  }
+
+  void EncodeLengthPrefixedKey(const Slice& key) {
+    auto size = key.size();
+    EnlargeBufferIfNeeded(size + VarintLength(size));
+    char* ptr = EncodeVarint32(key_, size);
+    memcpy(ptr, key.data(), size);
+  }
+
+ private:
+  char* key_;
+  size_t buf_size_;
+  size_t key_size_;
+  char space_[32];  // Avoid allocation for short keys
+
+  void ResetBuffer() {
+    if (key_ != nullptr && key_ != space_) {
+      delete[] key_;
+    }
+    key_ = space_;
+    buf_size_ = sizeof(space_);
+    key_size_ = 0;
+  }
+
+  // Enlarge the buffer size if needed based on key_size.
+  // By default, static allocated buffer is used. Once there is a key
+  // larger than the static allocated buffer, another buffer is dynamically
+  // allocated, until a larger key buffer is requested. In that case, we
+  // reallocate buffer and delete the old one.
+  void EnlargeBufferIfNeeded(size_t key_size) {
+    // If size is smaller than buffer size, continue using current buffer,
+    // or the static allocated one, as default
+    if (key_size > buf_size_) {
+      // Need to enlarge the buffer.
+      ResetBuffer();
+      key_ = new char[key_size];
+      buf_size_ = key_size;
+    }
+  }
+
+  // No copying allowed
+  IterKey(const IterKey&) = delete;
+  void operator=(const IterKey&) = delete;
+};
+
+class InternalKeySliceTransform : public SliceTransform {
+ public:
+  explicit InternalKeySliceTransform(const SliceTransform* transform)
+      : transform_(transform) {}
+
+  virtual const char* Name() const { return transform_->Name(); }
+
+  virtual Slice Transform(const Slice& src) const {
+    auto user_key = ExtractUserKey(src);
+    return transform_->Transform(user_key);
+  }
+
+  virtual bool InDomain(const Slice& src) const {
+    auto user_key = ExtractUserKey(src);
+    return transform_->InDomain(user_key);
+  }
+
+  virtual bool InRange(const Slice& dst) const {
+    auto user_key = ExtractUserKey(dst);
+    return transform_->InRange(user_key);
+  }
+
+  const SliceTransform* user_prefix_extractor() const { return transform_; }
+
+ private:
+  // Like comparator, InternalKeySliceTransform will not take care of the
+  // deletion of transform_
+  const SliceTransform* const transform_;
+};
+
+}  // namespace rocksdb

db/dbformat_test.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

db/deletefile_test.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -9,12 +14,12 @@
 #include "db/write_batch_internal.h"
 #include "util/testharness.h"
 #include "util/testutil.h"
-#include "boost/lexical_cast.hpp"
 #include "rocksdb/env.h"
+#include "rocksdb/transaction_log.h"
 #include <vector>
-#include <boost/algorithm/string.hpp>
 #include <stdlib.h>
 #include <map>
+#include <string>
 
 namespace rocksdb {
 
@@ -32,7 +37,22 @@ class DeleteFileTest {
     options_.write_buffer_size = 1024*1024*1000;
     options_.target_file_size_base = 1024*1024*1000;
     options_.max_bytes_for_level_base = 1024*1024*1000;
+    options_.WAL_ttl_seconds = 300; // Used to test log files
+    options_.WAL_size_limit_MB = 1024; // Used to test log files
     dbname_ = test::TmpDir() + "/deletefile_test";
+    options_.wal_dir = dbname_ + "/wal_files";
+
+    // clean up all the files that might have been there before
+    std::vector<std::string> old_files;
+    env_->GetChildren(dbname_, &old_files);
+    for (auto file : old_files) {
+      env_->DeleteFile(dbname_ + "/" + file);
+    }
+    env_->GetChildren(options_.wal_dir, &old_files);
+    for (auto file : old_files) {
+      env_->DeleteFile(options_.wal_dir + "/" + file);
+    }
+
     DestroyDB(dbname_, options_);
     numlevels_ = 7;
     ASSERT_OK(ReopenDB(true));
@@ -57,7 +77,7 @@ class DeleteFileTest {
     options.sync = false;
     ReadOptions roptions;
     for (int i = startkey; i < (numkeys + startkey) ; i++) {
-      std::string temp = boost::lexical_cast<std::string>(i);
+      std::string temp = std::to_string(i);
       Slice key(temp);
       Slice value(temp);
       ASSERT_OK(db_->Put(options, key, value));
@@ -92,12 +112,34 @@ class DeleteFileTest {
   void CreateTwoLevels() {
     AddKeys(50000, 10000);
     DBImpl* dbi = reinterpret_cast<DBImpl*>(db_);
-    ASSERT_OK(dbi->TEST_CompactMemTable());
-    ASSERT_OK(dbi->TEST_WaitForCompactMemTable());
+    ASSERT_OK(dbi->TEST_FlushMemTable());
+    ASSERT_OK(dbi->TEST_WaitForFlushMemTable());
 
     AddKeys(50000, 10000);
-    ASSERT_OK(dbi->TEST_CompactMemTable());
-    ASSERT_OK(dbi->TEST_WaitForCompactMemTable());
+    ASSERT_OK(dbi->TEST_FlushMemTable());
+    ASSERT_OK(dbi->TEST_WaitForFlushMemTable());
+  }
+
+  void CheckFileTypeCounts(std::string& dir,
+                            int required_log,
+                            int required_sst,
+                            int required_manifest) {
+    std::vector<std::string> filenames;
+    env_->GetChildren(dir, &filenames);
+
+    int log_cnt = 0, sst_cnt = 0, manifest_cnt = 0;
+    for (auto file : filenames) {
+      uint64_t number;
+      FileType type;
+      if (ParseFileName(file, &number, &type)) {
+        log_cnt += (type == kLogFile);
+        sst_cnt += (type == kTableFile);
+        manifest_cnt += (type == kDescriptorFile);
+      }
+    }
+    ASSERT_EQ(required_log, log_cnt);
+    ASSERT_EQ(required_sst, sst_cnt);
+    ASSERT_EQ(required_manifest, manifest_cnt);
   }
 
 };
@@ -149,6 +191,33 @@ TEST(DeleteFileTest, AddKeysAndQueryLevels) {
   CloseDB();
 }
 
+TEST(DeleteFileTest, PurgeObsoleteFilesTest) {
+  CreateTwoLevels();
+  // there should be only one (empty) log file because CreateTwoLevels()
+  // flushes the memtables to disk
+  CheckFileTypeCounts(options_.wal_dir, 1, 0, 0);
+  // 2 ssts, 1 manifest
+  CheckFileTypeCounts(dbname_, 0, 2, 1);
+  std::string first("0"), last("999999");
+  Slice first_slice(first), last_slice(last);
+  db_->CompactRange(&first_slice, &last_slice, true, 2);
+  // 1 sst after compaction
+  CheckFileTypeCounts(dbname_, 0, 1, 1);
+
+  // this time, we keep an iterator alive
+  ReopenDB(true);
+  Iterator *itr = 0;
+  CreateTwoLevels();
+  itr = db_->NewIterator(ReadOptions());
+  db_->CompactRange(&first_slice, &last_slice, true, 2);
+  // 3 sst after compaction with live iterator
+  CheckFileTypeCounts(dbname_, 0, 3, 1);
+  delete itr;
+  // 1 sst after iterator deletion
+  CheckFileTypeCounts(dbname_, 0, 1, 1);
+
+  CloseDB();
+}
 
 TEST(DeleteFileTest, DeleteFileWithIterator) {
   CreateTwoLevels();
@@ -180,6 +249,44 @@ TEST(DeleteFileTest, DeleteFileWithIterator) {
   delete it;
   CloseDB();
 }
+
+TEST(DeleteFileTest, DeleteLogFiles) {
+  AddKeys(10, 0);
+  VectorLogPtr logfiles;
+  db_->GetSortedWalFiles(logfiles);
+  ASSERT_GT(logfiles.size(), 0UL);
+  // Take the last log file which is expected to be alive and try to delete it
+  // Should not succeed because live logs are not allowed to be deleted
+  std::unique_ptr<LogFile> alive_log = std::move(logfiles.back());
+  ASSERT_EQ(alive_log->Type(), kAliveLogFile);
+  ASSERT_TRUE(env_->FileExists(options_.wal_dir + "/" + alive_log->PathName()));
+  fprintf(stdout, "Deleting alive log file %s\n",
+          alive_log->PathName().c_str());
+  ASSERT_TRUE(!db_->DeleteFile(alive_log->PathName()).ok());
+  ASSERT_TRUE(env_->FileExists(options_.wal_dir + "/" + alive_log->PathName()));
+  logfiles.clear();
+
+  // Call Flush to bring about a new working log file and add more keys
+  // Call Flush again to flush out memtable and move alive log to archived log
+  // and try to delete the archived log file
+  FlushOptions fopts;
+  db_->Flush(fopts);
+  AddKeys(10, 0);
+  db_->Flush(fopts);
+  db_->GetSortedWalFiles(logfiles);
+  ASSERT_GT(logfiles.size(), 0UL);
+  std::unique_ptr<LogFile> archived_log = std::move(logfiles.front());
+  ASSERT_EQ(archived_log->Type(), kArchivedLogFile);
+  ASSERT_TRUE(env_->FileExists(options_.wal_dir + "/" +
+        archived_log->PathName()));
+  fprintf(stdout, "Deleting archived log file %s\n",
+          archived_log->PathName().c_str());
+  ASSERT_OK(db_->DeleteFile(archived_log->PathName()));
+  ASSERT_TRUE(!env_->FileExists(options_.wal_dir + "/" +
+        archived_log->PathName()));
+  CloseDB();
+}
+
 } //namespace rocksdb
 
 int main(int argc, char** argv) {

db/file_indexer.cc

@@ -0,0 +1,202 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "db/file_indexer.h"
+#include <algorithm>
+#include "rocksdb/comparator.h"
+#include "db/version_edit.h"
+
+namespace rocksdb {
+
+FileIndexer::FileIndexer(const uint32_t num_levels,
+                         const Comparator* ucmp)
+  : num_levels_(num_levels),
+    ucmp_(ucmp),
+    next_level_index_(num_levels),
+    level_rb_(num_levels, -1) {
+}
+
+
+uint32_t FileIndexer::NumLevelIndex() {
+  return next_level_index_.size();
+}
+
+uint32_t FileIndexer::LevelIndexSize(uint32_t level) {
+  return next_level_index_[level].size();
+}
+
+void FileIndexer::GetNextLevelIndex(
+    const uint32_t level, const uint32_t file_index, const int cmp_smallest,
+    const int cmp_largest, int32_t* left_bound, int32_t* right_bound) {
+  assert(level > 0);
+
+  // Last level, no hint
+  if (level == num_levels_ - 1) {
+    *left_bound = 0;
+    *right_bound = -1;
+    return;
+  }
+
+  assert(level < num_levels_ - 1);
+  assert(static_cast<int32_t>(file_index) <= level_rb_[level]);
+
+  const auto& index = next_level_index_[level][file_index];
+
+  if (cmp_smallest < 0) {
+    *left_bound = (level > 0 && file_index > 0) ?
+      next_level_index_[level][file_index - 1].largest_lb : 0;
+    *right_bound = index.smallest_rb;
+  } else if (cmp_smallest == 0) {
+    *left_bound = index.smallest_lb;
+    *right_bound = index.smallest_rb;
+  } else if (cmp_smallest > 0 && cmp_largest < 0) {
+    *left_bound = index.smallest_lb;
+    *right_bound = index.largest_rb;
+  } else if (cmp_largest == 0) {
+    *left_bound = index.largest_lb;
+    *right_bound = index.largest_rb;
+  } else if (cmp_largest > 0) {
+    *left_bound = index.largest_lb;
+    *right_bound = level_rb_[level + 1];
+  } else {
+    assert(false);
+  }
+
+  assert(*left_bound >= 0);
+  assert(*left_bound <= *right_bound + 1);
+  assert(*right_bound <= level_rb_[level + 1]);
+}
+
+void FileIndexer::ClearIndex() {
+  for (uint32_t level = 1; level < num_levels_; ++level) {
+    next_level_index_[level].clear();
+  }
+}
+
+void FileIndexer::UpdateIndex(std::vector<FileMetaData*>* const files) {
+  if (files == nullptr) {
+    return;
+  }
+
+  // L1 - Ln-1
+  for (uint32_t level = 1; level < num_levels_ - 1; ++level) {
+    const auto& upper_files = files[level];
+    const int32_t upper_size = upper_files.size();
+    const auto& lower_files = files[level + 1];
+    level_rb_[level] = upper_files.size() - 1;
+    if (upper_size == 0) {
+      continue;
+    }
+    auto& index = next_level_index_[level];
+    index.resize(upper_size);
+
+    CalculateLB(upper_files, lower_files, &index,
+        [this](const FileMetaData* a, const FileMetaData* b) -> int {
+          return ucmp_->Compare(a->smallest.user_key(), b->largest.user_key());
+        },
+        [](IndexUnit* index, int32_t f_idx) {
+          index->smallest_lb = f_idx;
+        });
+    CalculateLB(upper_files, lower_files, &index,
+        [this](const FileMetaData* a, const FileMetaData* b) -> int {
+          return ucmp_->Compare(a->largest.user_key(), b->largest.user_key());
+        },
+        [](IndexUnit* index, int32_t f_idx) {
+          index->largest_lb = f_idx;
+        });
+    CalculateRB(upper_files, lower_files, &index,
+        [this](const FileMetaData* a, const FileMetaData* b) -> int {
+          return ucmp_->Compare(a->smallest.user_key(), b->smallest.user_key());
+        },
+        [](IndexUnit* index, int32_t f_idx) {
+          index->smallest_rb = f_idx;
+        });
+    CalculateRB(upper_files, lower_files, &index,
+        [this](const FileMetaData* a, const FileMetaData* b) -> int {
+          return ucmp_->Compare(a->largest.user_key(), b->smallest.user_key());
+        },
+        [](IndexUnit* index, int32_t f_idx) {
+          index->largest_rb = f_idx;
+        });
+  }
+  level_rb_[num_levels_ - 1] = files[num_levels_ - 1].size() - 1;
+}
+
+void FileIndexer::CalculateLB(const std::vector<FileMetaData*>& upper_files,
+    const std::vector<FileMetaData*>& lower_files,
+    std::vector<IndexUnit>* index,
+    std::function<int(const FileMetaData*, const FileMetaData*)> cmp_op,
+    std::function<void(IndexUnit*, int32_t)> set_index) {
+  const int32_t upper_size = upper_files.size();
+  const int32_t lower_size = lower_files.size();
+  int32_t upper_idx = 0;
+  int32_t lower_idx = 0;
+  while (upper_idx < upper_size && lower_idx < lower_size) {
+    int cmp = cmp_op(upper_files[upper_idx], lower_files[lower_idx]);
+
+    if (cmp == 0) {
+      set_index(&(*index)[upper_idx], lower_idx);
+      ++upper_idx;
+      ++lower_idx;
+    } else if (cmp > 0) {
+      // Lower level's file (largest) is smaller, a key won't hit in that
+      // file. Move to next lower file
+      ++lower_idx;
+    } else {
+      // Lower level's file becomes larger, update the index, and
+      // move to the next upper file
+      set_index(&(*index)[upper_idx], lower_idx);
+      ++upper_idx;
+    }
+  }
+
+  while (upper_idx < upper_size) {
+    // Lower files are exhausted, that means the remaining upper files are
+    // greater than any lower files. Set the index to be the lower level size.
+    set_index(&(*index)[upper_idx], lower_size);
+    ++upper_idx;
+  }
+}
+
+void FileIndexer::CalculateRB(const std::vector<FileMetaData*>& upper_files,
+    const std::vector<FileMetaData*>& lower_files,
+    std::vector<IndexUnit>* index,
+    std::function<int(const FileMetaData*, const FileMetaData*)> cmp_op,
+    std::function<void(IndexUnit*, int32_t)> set_index) {
+  const int32_t upper_size = upper_files.size();
+  const int32_t lower_size = lower_files.size();
+  int32_t upper_idx = upper_size - 1;
+  int32_t lower_idx = lower_size - 1;
+  while (upper_idx >= 0 && lower_idx >= 0) {
+    int cmp = cmp_op(upper_files[upper_idx], lower_files[lower_idx]);
+
+    if (cmp == 0) {
+      set_index(&(*index)[upper_idx], lower_idx);
+      --upper_idx;
+      --lower_idx;
+    } else if (cmp < 0) {
+      // Lower level's file (smallest) is larger, a key won't hit in that
+      // file. Move to next lower file.
+      --lower_idx;
+    } else {
+      // Lower level's file becomes smaller, update the index, and move to
+      // the next the upper file
+      set_index(&(*index)[upper_idx], lower_idx);
+      --upper_idx;
+    }
+  }
+  while (upper_idx >= 0) {
+    // Lower files are exhausted, that means the remaining upper files are
+    // smaller than any lower files. Set it to -1.
+    set_index(&(*index)[upper_idx], -1);
+    --upper_idx;
+  }
+}
+
+}  // namespace rocksdb

db/file_indexer.h

@@ -0,0 +1,129 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#pragma once
+#include <cstdint>
+#include <functional>
+#include <limits>
+#include <vector>
+
+namespace rocksdb {
+
+class Comparator;
+struct FileMetaData;
+
+// The file tree structure in Version is prebuilt and the range of each file
+// is known. On Version::Get(), it uses binary search to find a potential file
+// and then check if a target key can be found in the file by comparing the key
+// to each file's smallest and largest key. The results of these comparisions
+// can be reused beyond checking if a key falls into a file's range.
+// With some pre-calculated knowledge, each key comparision that has been done
+// can serve as a hint to narrow down further searches: if a key compared to
+// be smaller than a file's smallest or largest, that comparison can be used
+// to find out the right bound of next binary search. Similarly, if a key
+// compared to be larger than a file's smallest or largest, it can be utilized
+// to find out the left bound of next binary search.
+// With these hints: it can greatly reduce the range of binary search,
+// especially for bottom levels, given that one file most likely overlaps with
+// only N files from level below (where N is max_bytes_for_level_multiplier).
+// So on level L, we will only look at ~N files instead of N^L files on the
+// naive approach.
+class FileIndexer {
+ public:
+  FileIndexer(const uint32_t num_levels, const Comparator* ucmp);
+
+  uint32_t NumLevelIndex();
+
+  uint32_t LevelIndexSize(uint32_t level);
+
+  // Return a file index range in the next level to search for a key based on
+  // smallest and largest key comparision for the current file specified by
+  // level and file_index. When *left_index < *right_index, both index should
+  // be valid and fit in the vector size.
+  void GetNextLevelIndex(
+    const uint32_t level, const uint32_t file_index, const int cmp_smallest,
+    const int cmp_largest, int32_t* left_bound, int32_t* right_bound);
+
+  void ClearIndex();
+
+  void UpdateIndex(std::vector<FileMetaData*>* const files);
+
+  enum {
+    kLevelMaxIndex = std::numeric_limits<int32_t>::max()
+  };
+
+ private:
+  const uint32_t num_levels_;
+  const Comparator* ucmp_;
+
+  struct IndexUnit {
+    IndexUnit()
+      : smallest_lb(0), largest_lb(0), smallest_rb(-1), largest_rb(-1) {}
+    // During file search, a key is compared against smallest and largest
+    // from a FileMetaData. It can have 3 possible outcomes:
+    // (1) key is smaller than smallest, implying it is also smaller than
+    //     larger. Precalculated index based on "smallest < smallest" can
+    //     be used to provide right bound.
+    // (2) key is in between smallest and largest.
+    //     Precalculated index based on "smallest > greatest" can be used to
+    //     provide left bound.
+    //     Precalculated index based on "largest < smallest" can be used to
+    //     provide right bound.
+    // (3) key is larger than largest, implying it is also larger than smallest.
+    //     Precalculated index based on "largest > largest" can be used to
+    //     provide left bound.
+    //
+    // As a result, we will need to do:
+    // Compare smallest (<=) and largest keys from upper level file with
+    // smallest key from lower level to get a right bound.
+    // Compare smallest (>=) and largest keys from upper level file with
+    // largest key from lower level to get a left bound.
+    //
+    // Example:
+    //    level 1:              [50 - 60]
+    //    level 2:        [1 - 40], [45 - 55], [58 - 80]
+    // A key 35, compared to be less than 50, 3rd file on level 2 can be
+    // skipped according to rule (1). LB = 0, RB = 1.
+    // A key 53, sits in the middle 50 and 60. 1st file on level 2 can be
+    // skipped according to rule (2)-a, but the 3rd file cannot be skipped
+    // because 60 is greater than 58. LB = 1, RB = 2.
+    // A key 70, compared to be larger than 60. 1st and 2nd file can be skipped
+    // according to rule (3). LB = 2, RB = 2.
+    //
+    // Point to a left most file in a lower level that may contain a key,
+    // which compares greater than smallest of a FileMetaData (upper level)
+    int32_t smallest_lb;
+    // Point to a left most file in a lower level that may contain a key,
+    // which compares greater than largest of a FileMetaData (upper level)
+    int32_t largest_lb;
+    // Point to a right most file in a lower level that may contain a key,
+    // which compares smaller than smallest of a FileMetaData (upper level)
+    int32_t smallest_rb;
+    // Point to a right most file in a lower level that may contain a key,
+    // which compares smaller than largest of a FileMetaData (upper level)
+    int32_t largest_rb;
+  };
+
+  void CalculateLB(const std::vector<FileMetaData*>& upper_files,
+    const std::vector<FileMetaData*>& lower_files,
+    std::vector<IndexUnit>* index,
+    std::function<int(const FileMetaData*, const FileMetaData*)> cmp_op,
+    std::function<void(IndexUnit*, int32_t)> set_index);
+
+  void CalculateRB(const std::vector<FileMetaData*>& upper_files,
+    const std::vector<FileMetaData*>& lower_files,
+    std::vector<IndexUnit>* index,
+    std::function<int(const FileMetaData*, const FileMetaData*)> cmp_op,
+    std::function<void(IndexUnit*, int32_t)> set_index);
+
+  std::vector<std::vector<IndexUnit>> next_level_index_;
+  std::vector<int32_t> level_rb_;
+};
+
+}  // namespace rocksdb

db/file_indexer_test.cc

@@ -0,0 +1,330 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include <string>
+#include "db/file_indexer.h"
+#include "db/dbformat.h"
+#include "db/version_edit.h"
+#include "rocksdb/comparator.h"
+#include "util/testharness.h"
+#include "util/testutil.h"
+
+namespace rocksdb {
+
+class IntComparator : public Comparator {
+ public:
+  int Compare(const Slice& a, const Slice& b) const {
+    assert(a.size() == 8);
+    assert(b.size() == 8);
+    return *reinterpret_cast<const int64_t*>(a.data()) -
+      *reinterpret_cast<const int64_t*>(b.data());
+  }
+
+  const char* Name() const {
+    return "IntComparator";
+  }
+
+  void FindShortestSeparator(std::string* start, const Slice& limit) const {}
+
+  void FindShortSuccessor(std::string* key) const {}
+};
+
+
+struct FileIndexerTest {
+ public:
+  FileIndexerTest() :
+    kNumLevels(4), indexer(kNumLevels, &ucmp),
+    files(new std::vector<FileMetaData*>[kNumLevels]) {
+  }
+
+  ~FileIndexerTest() {
+    Reset();
+    delete[] files;
+  }
+
+  void AddFile(int level, int64_t smallest, int64_t largest) {
+    auto* f = new FileMetaData();
+    f->smallest = IntKey(smallest);
+    f->largest = IntKey(largest);
+    files[level].push_back(f);
+  }
+
+  InternalKey IntKey(int64_t v) {
+    return InternalKey(Slice(reinterpret_cast<char*>(&v), 8), 0, kTypeValue);
+  }
+
+  void Reset() {
+    for (uint32_t i = 0; i < kNumLevels; ++i) {
+      for (auto* f : files[i]) {
+        delete f;
+      }
+      files[i].clear();
+    }
+    indexer.ClearIndex();
+  }
+
+  void GetNextLevelIndex(const uint32_t level, const uint32_t file_index,
+      const int cmp_smallest, const int cmp_largest, int32_t* left_index,
+      int32_t* right_index) {
+    *left_index = 100;
+    *right_index = 100;
+    indexer.GetNextLevelIndex(level, file_index, cmp_smallest, cmp_largest,
+        left_index, right_index);
+  }
+
+  const uint32_t kNumLevels;
+  IntComparator ucmp;
+  FileIndexer indexer;
+
+  std::vector<FileMetaData*>* files;
+};
+
+TEST(FileIndexerTest, next_level_hint) {
+  for (uint32_t i = 0; i < kNumLevels; ++i) {
+    ASSERT_EQ(0U, indexer.LevelIndexSize(i));
+  }
+
+  // Case 1: no overlap, files are on the left of next level files
+  // level 1
+  AddFile(1, 100, 200);
+  AddFile(1, 300, 400);
+  AddFile(1, 500, 600);
+  // level 2
+  AddFile(2, 1500, 1600);
+  AddFile(2, 1601, 1699);
+  AddFile(2, 1700, 1800);
+  // level 3
+  AddFile(3, 2500, 2600);
+  AddFile(3, 2601, 2699);
+  AddFile(3, 2700, 2800);
+  indexer.UpdateIndex(files);
+  int32_t left = 100;
+  int32_t right = 100;
+  for (uint32_t level = 1; level < 3; ++level) {
+    for (uint32_t f = 0; f < 3; ++f) {
+      GetNextLevelIndex(level, f, -1, -1, &left, &right);
+      ASSERT_EQ(0, left);
+      ASSERT_EQ(-1, right);
+      GetNextLevelIndex(level, f, 0, -1, &left, &right);
+      ASSERT_EQ(0, left);
+      ASSERT_EQ(-1, right);
+      GetNextLevelIndex(level, f, 1, -1, &left, &right);
+      ASSERT_EQ(0, left);
+      ASSERT_EQ(-1, right);
+      GetNextLevelIndex(level, f, 1, 0, &left, &right);
+      ASSERT_EQ(0, left);
+      ASSERT_EQ(-1, right);
+      GetNextLevelIndex(level, f, 1, 1, &left, &right);
+      ASSERT_EQ(0, left);
+      ASSERT_EQ(2, right);
+    }
+  }
+
+  // Case 2: no overlap, files are on the right of next level files
+  Reset();
+  for (uint32_t i = 1; i < kNumLevels; ++i) {
+    ASSERT_EQ(0U, indexer.LevelIndexSize(i));
+  }
+  // level 1
+  AddFile(1, 2100, 2200);
+  AddFile(1, 2300, 2400);
+  AddFile(1, 2500, 2600);
+  // level 2
+  AddFile(2, 1500, 1600);
+  AddFile(2, 1501, 1699);
+  AddFile(2, 1700, 1800);
+  // level 3
+  AddFile(3, 500, 600);
+  AddFile(3, 501, 699);
+  AddFile(3, 700, 800);
+  indexer.UpdateIndex(files);
+  for (uint32_t level = 1; level < 3; ++level) {
+    for (uint32_t f = 0; f < 3; ++f) {
+      GetNextLevelIndex(level, f, -1, -1, &left, &right);
+      ASSERT_EQ(f == 0 ? 0 : 3, left);
+      ASSERT_EQ(2, right);
+      GetNextLevelIndex(level, f, 0, -1, &left, &right);
+      ASSERT_EQ(3, left);
+      ASSERT_EQ(2, right);
+      GetNextLevelIndex(level, f, 1, -1, &left, &right);
+      ASSERT_EQ(3, left);
+      ASSERT_EQ(2, right);
+      GetNextLevelIndex(level, f, 1, -1, &left, &right);
+      ASSERT_EQ(3, left);
+      ASSERT_EQ(2, right);
+      GetNextLevelIndex(level, f, 1, 0, &left, &right);
+      ASSERT_EQ(3, left);
+      ASSERT_EQ(2, right);
+      GetNextLevelIndex(level, f, 1, 1, &left, &right);
+      ASSERT_EQ(3, left);
+      ASSERT_EQ(2, right);
+    }
+  }
+
+  // Case 3: empty L2
+  Reset();
+  for (uint32_t i = 1; i < kNumLevels; ++i) {
+    ASSERT_EQ(0U, indexer.LevelIndexSize(i));
+  }
+  // level 1
+  AddFile(1, 2100, 2200);
+  AddFile(1, 2300, 2400);
+  AddFile(1, 2500, 2600);
+  // level 3
+  AddFile(3, 500, 600);
+  AddFile(3, 501, 699);
+  AddFile(3, 700, 800);
+  indexer.UpdateIndex(files);
+  for (uint32_t f = 0; f < 3; ++f) {
+    GetNextLevelIndex(1, f, -1, -1, &left, &right);
+    ASSERT_EQ(0, left);
+    ASSERT_EQ(-1, right);
+    GetNextLevelIndex(1, f, 0, -1, &left, &right);
+    ASSERT_EQ(0, left);
+    ASSERT_EQ(-1, right);
+    GetNextLevelIndex(1, f, 1, -1, &left, &right);
+    ASSERT_EQ(0, left);
+    ASSERT_EQ(-1, right);
+    GetNextLevelIndex(1, f, 1, -1, &left, &right);
+    ASSERT_EQ(0, left);
+    ASSERT_EQ(-1, right);
+    GetNextLevelIndex(1, f, 1, 0, &left, &right);
+    ASSERT_EQ(0, left);
+    ASSERT_EQ(-1, right);
+    GetNextLevelIndex(1, f, 1, 1, &left, &right);
+    ASSERT_EQ(0, left);
+    ASSERT_EQ(-1, right);
+  }
+
+
+  // Case 4: mixed
+  Reset();
+  for (uint32_t i = 1; i < kNumLevels; ++i) {
+    ASSERT_EQ(0U, indexer.LevelIndexSize(i));
+  }
+  // level 1
+  AddFile(1, 100, 200);
+  AddFile(1, 250, 400);
+  AddFile(1, 450, 500);
+  // level 2
+  AddFile(2, 100, 150);  // 0
+  AddFile(2, 200, 250);  // 1
+  AddFile(2, 251, 300);  // 2
+  AddFile(2, 301, 350);  // 3
+  AddFile(2, 500, 600);  // 4
+  // level 3
+  AddFile(3, 0, 50);
+  AddFile(3, 100, 200);
+  AddFile(3, 201, 250);
+  indexer.UpdateIndex(files);
+  // level 1, 0
+  GetNextLevelIndex(1, 0, -1, -1, &left, &right);
+  ASSERT_EQ(0, left);
+  ASSERT_EQ(0, right);
+  GetNextLevelIndex(1, 0, 0, -1, &left, &right);
+  ASSERT_EQ(0, left);
+  ASSERT_EQ(0, right);
+  GetNextLevelIndex(1, 0, 1, -1, &left, &right);
+  ASSERT_EQ(0, left);
+  ASSERT_EQ(1, right);
+  GetNextLevelIndex(1, 0, 1, 0, &left, &right);
+  ASSERT_EQ(1, left);
+  ASSERT_EQ(1, right);
+  GetNextLevelIndex(1, 0, 1, 1, &left, &right);
+  ASSERT_EQ(1, left);
+  ASSERT_EQ(4, right);
+  // level 1, 1
+  GetNextLevelIndex(1, 1, -1, -1, &left, &right);
+  ASSERT_EQ(1, left);
+  ASSERT_EQ(1, right);
+  GetNextLevelIndex(1, 1, 0, -1, &left, &right);
+  ASSERT_EQ(1, left);
+  ASSERT_EQ(1, right);
+  GetNextLevelIndex(1, 1, 1, -1, &left, &right);
+  ASSERT_EQ(1, left);
+  ASSERT_EQ(3, right);
+  GetNextLevelIndex(1, 1, 1, 0, &left, &right);
+  ASSERT_EQ(4, left);
+  ASSERT_EQ(3, right);
+  GetNextLevelIndex(1, 1, 1, 1, &left, &right);
+  ASSERT_EQ(4, left);
+  ASSERT_EQ(4, right);
+  // level 1, 2
+  GetNextLevelIndex(1, 2, -1, -1, &left, &right);
+  ASSERT_EQ(4, left);
+  ASSERT_EQ(3, right);
+  GetNextLevelIndex(1, 2, 0, -1, &left, &right);
+  ASSERT_EQ(4, left);
+  ASSERT_EQ(3, right);
+  GetNextLevelIndex(1, 2, 1, -1, &left, &right);
+  ASSERT_EQ(4, left);
+  ASSERT_EQ(4, right);
+  GetNextLevelIndex(1, 2, 1, 0, &left, &right);
+  ASSERT_EQ(4, left);
+  ASSERT_EQ(4, right);
+  GetNextLevelIndex(1, 2, 1, 1, &left, &right);
+  ASSERT_EQ(4, left);
+  ASSERT_EQ(4, right);
+  // level 2, 0
+  GetNextLevelIndex(2, 0, -1, -1, &left, &right);
+  ASSERT_EQ(0, left);
+  ASSERT_EQ(1, right);
+  GetNextLevelIndex(2, 0, 0, -1, &left, &right);
+  ASSERT_EQ(1, left);
+  ASSERT_EQ(1, right);
+  GetNextLevelIndex(2, 0, 1, -1, &left, &right);
+  ASSERT_EQ(1, left);
+  ASSERT_EQ(1, right);
+  GetNextLevelIndex(2, 0, 1, 0, &left, &right);
+  ASSERT_EQ(1, left);
+  ASSERT_EQ(1, right);
+  GetNextLevelIndex(2, 0, 1, 1, &left, &right);
+  ASSERT_EQ(1, left);
+  ASSERT_EQ(2, right);
+  // level 2, 1
+  GetNextLevelIndex(2, 1, -1, -1, &left, &right);
+  ASSERT_EQ(1, left);
+  ASSERT_EQ(1, right);
+  GetNextLevelIndex(2, 1, 0, -1, &left, &right);
+  ASSERT_EQ(1, left);
+  ASSERT_EQ(1, right);
+  GetNextLevelIndex(2, 1, 1, -1, &left, &right);
+  ASSERT_EQ(1, left);
+  ASSERT_EQ(2, right);
+  GetNextLevelIndex(2, 1, 1, 0, &left, &right);
+  ASSERT_EQ(2, left);
+  ASSERT_EQ(2, right);
+  GetNextLevelIndex(2, 1, 1, 1, &left, &right);
+  ASSERT_EQ(2, left);
+  ASSERT_EQ(2, right);
+  // level 2, [2 - 4], no overlap
+  for (uint32_t f = 2; f <= 4; ++f) {
+    GetNextLevelIndex(2, f, -1, -1, &left, &right);
+    ASSERT_EQ(f == 2 ? 2 : 3, left);
+    ASSERT_EQ(2, right);
+    GetNextLevelIndex(2, f, 0, -1, &left, &right);
+    ASSERT_EQ(3, left);
+    ASSERT_EQ(2, right);
+    GetNextLevelIndex(2, f, 1, -1, &left, &right);
+    ASSERT_EQ(3, left);
+    ASSERT_EQ(2, right);
+    GetNextLevelIndex(2, f, 1, 0, &left, &right);
+    ASSERT_EQ(3, left);
+    ASSERT_EQ(2, right);
+    GetNextLevelIndex(2, f, 1, 1, &left, &right);
+    ASSERT_EQ(3, left);
+    ASSERT_EQ(2, right);
+  }
+}
+
+}  // namespace rocksdb
+
+int main(int argc, char** argv) {
+  return rocksdb::test::RunAllTests();
+}

db/filename.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -6,6 +11,7 @@
 
 #include <ctype.h>
 #include <stdio.h>
+#include <vector>
 #include "db/dbformat.h"
 #include "rocksdb/env.h"
 #include "util/logging.h"
@@ -39,10 +45,6 @@ static int FlattenPath(const std::string& path, char* dest, int len) {
   return write_idx;
 }
 
-// A utility routine: write "data" to the named file and Sync() it.
-extern Status WriteStringToFileSync(Env* env, const Slice& data,
-                                    const std::string& fname);
-
 static std::string MakeFileName(const std::string& name, uint64_t number,
                                 const char* suffix) {
   char buf[100];
@@ -57,17 +59,36 @@ std::string LogFileName(const std::string& name, uint64_t number) {
   return MakeFileName(name, number, "log");
 }
 
-std::string ArchivalDirectory(const std::string& dbname) {
-  return dbname + "/" + ARCHIVAL_DIR;
+std::string ArchivalDirectory(const std::string& dir) {
+  return dir + "/" + ARCHIVAL_DIR;
 }
 std::string ArchivedLogFileName(const std::string& name, uint64_t number) {
   assert(number > 0);
   return MakeFileName(name + "/" + ARCHIVAL_DIR, number, "log");
 }
 
-std::string TableFileName(const std::string& name, uint64_t number) {
+std::string MakeTableFileName(const std::string& path, uint64_t number) {
+  return MakeFileName(path, number, "sst");
+}
+
+std::string TableFileName(const std::vector<std::string> db_paths,
+                          uint64_t number, uint32_t path_id) {
   assert(number > 0);
-  return MakeFileName(name, number, "sst");
+  std::string path;
+  if (path_id >= db_paths.size()) {
+    path = db_paths.back();
+  } else {
+    path = db_paths[path_id];
+  }
+  return MakeTableFileName(path, number);
+}
+
+std::string FormatFileNumber(uint64_t number, uint32_t path_id) {
+  if (path_id == 0) {
+    return std::to_string(number);
+  } else {
+    return std::to_string(number) + "(path " + std::to_string(path_id) + ")";
+  }
 }
 
 std::string DescriptorFileName(const std::string& dbname, uint64_t number) {
@@ -87,7 +108,6 @@ std::string LockFileName(const std::string& dbname) {
 }
 
 std::string TempFileName(const std::string& dbname, uint64_t number) {
-  assert(number > 0);
   return MakeFileName(dbname, number, "dbtmp");
 }
 
@@ -122,7 +142,12 @@ std::string MetaDatabaseName(const std::string& dbname, uint64_t number) {
   return dbname + buf;
 }
 
+std::string IdentityFileName(const std::string& dbname) {
+  return dbname + "/IDENTITY";
+}
+
 // Owned filenames have the form:
+//    dbname/IDENTITY
 //    dbname/CURRENT
 //    dbname/LOCK
 //    dbname/LOG
@@ -133,12 +158,16 @@ std::string MetaDatabaseName(const std::string& dbname, uint64_t number) {
 //    Disregards / at the beginning
 bool ParseFileName(const std::string& fname,
                    uint64_t* number,
-                   FileType* type) {
+                   FileType* type,
+                   WalFileType* log_type) {
   Slice rest(fname);
   if (fname.length() > 1 && fname[0] == '/') {
     rest.remove_prefix(1);
   }
-  if (rest == "CURRENT") {
+  if (rest == "IDENTITY") {
+    *number = 0;
+    *type = kIdentityFile;
+  } else if (rest == "CURRENT") {
     *number = 0;
     *type = kCurrentFile;
   } else if (rest == "LOCK") {
@@ -181,6 +210,17 @@ bool ParseFileName(const std::string& fname,
   } else {
     // Avoid strtoull() to keep filename format independent of the
     // current locale
+    bool archive_dir_found = false;
+    if (rest.starts_with(ARCHIVAL_DIR)) {
+      if (rest.size() <= ARCHIVAL_DIR.size()) {
+        return false;
+      }
+      rest.remove_prefix(ARCHIVAL_DIR.size() + 1); // Add 1 to remove / also
+      if (log_type) {
+        *log_type = kArchivedLogFile;
+      }
+      archive_dir_found = true;
+    }
     uint64_t num;
     if (!ConsumeDecimalNumber(&rest, &num)) {
       return false;
@@ -188,6 +228,11 @@ bool ParseFileName(const std::string& fname,
     Slice suffix = rest;
     if (suffix == Slice(".log")) {
       *type = kLogFile;
+      if (log_type && !archive_dir_found) {
+        *log_type = kAliveLogFile;
+      }
+    } else if (archive_dir_found) {
+      return false; // Archive dir can contain only log files
     } else if (suffix == Slice(".sst")) {
       *type = kTableFile;
     } else if (suffix == Slice(".dbtmp")) {
@@ -201,17 +246,37 @@ bool ParseFileName(const std::string& fname,
 }
 
 Status SetCurrentFile(Env* env, const std::string& dbname,
-                      uint64_t descriptor_number) {
+                      uint64_t descriptor_number,
+                      Directory* directory_to_fsync) {
   // Remove leading "dbname/" and add newline to manifest file name
   std::string manifest = DescriptorFileName(dbname, descriptor_number);
   Slice contents = manifest;
   assert(contents.starts_with(dbname + "/"));
   contents.remove_prefix(dbname.size() + 1);
   std::string tmp = TempFileName(dbname, descriptor_number);
-  Status s = WriteStringToFileSync(env, contents.ToString() + "\n", tmp);
+  Status s = WriteStringToFile(env, contents.ToString() + "\n", tmp, true);
   if (s.ok()) {
     s = env->RenameFile(tmp, CurrentFileName(dbname));
   }
+  if (s.ok()) {
+    if (directory_to_fsync != nullptr) {
+      directory_to_fsync->Fsync();
+    }
+  } else {
+    env->DeleteFile(tmp);
+  }
+  return s;
+}
+
+Status SetIdentityFile(Env* env, const std::string& dbname) {
+  std::string id = env->GenerateUniqueId();
+  assert(!id.empty());
+  // Reserve the filename dbname/000000.dbtmp for the temporary identity file
+  std::string tmp = TempFileName(dbname, 0);
+  Status s = WriteStringToFile(env, id, tmp, true);
+  if (s.ok()) {
+    s = env->RenameFile(tmp, IdentityFileName(dbname));
+  }
   if (!s.ok()) {
     env->DeleteFile(tmp);
   }

db/filename.h

@@ -1,21 +1,28 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 //
 // File names used by DB code
 
-#ifndef STORAGE_LEVELDB_DB_FILENAME_H_
-#define STORAGE_LEVELDB_DB_FILENAME_H_
-
+#pragma once
 #include <stdint.h>
+#include <unordered_map>
 #include <string>
+#include <vector>
 #include "rocksdb/slice.h"
 #include "rocksdb/status.h"
+#include "rocksdb/transaction_log.h"
 #include "port/port.h"
 
 namespace rocksdb {
 
 class Env;
+class Directory;
 
 enum FileType {
   kLogFile,
@@ -25,9 +32,13 @@ enum FileType {
   kCurrentFile,
   kTempFile,
   kInfoLogFile,  // Either the current one, or an old one
-  kMetaDatabase
+  kMetaDatabase,
+  kIdentityFile
 };
 
+// map from file number to path ID.
+typedef std::unordered_map<uint64_t, uint32_t> FileNumToPathIdMap;
+
 // Return the name of the log file with the specified number
 // in the db named by "dbname".  The result will be prefixed with
 // "dbname".
@@ -42,10 +53,15 @@ extern std::string ArchivalDirectory(const std::string& dbname);
 extern std::string ArchivedLogFileName(const std::string& dbname,
                                        uint64_t num);
 
+extern std::string MakeTableFileName(const std::string& name, uint64_t number);
+
 // Return the name of the sstable with the specified number
 // in the db named by "dbname".  The result will be prefixed with
 // "dbname".
-extern std::string TableFileName(const std::string& dbname, uint64_t number);
+extern std::string TableFileName(const std::vector<std::string> db_paths,
+                                 uint64_t number, uint32_t path_id);
+
+extern std::string FormatFileNumber(uint64_t number, uint32_t path_id);
 
 // Return the name of the descriptor file for the db named by
 // "dbname" and the specified incarnation number.  The result will be
@@ -79,19 +95,26 @@ extern std::string OldInfoLogFileName(const std::string& dbname, uint64_t ts,
 extern std::string MetaDatabaseName(const std::string& dbname,
                                     uint64_t number);
 
-// If filename is a leveldb file, store the type of the file in *type.
+// Return the name of the Identity file which stores a unique number for the db
+// that will get regenerated if the db loses all its data and is recreated fresh
+// either from a backup-image or empty
+extern std::string IdentityFileName(const std::string& dbname);
+
+// If filename is a rocksdb file, store the type of the file in *type.
 // The number encoded in the filename is stored in *number.  If the
 // filename was successfully parsed, returns true.  Else return false.
 extern bool ParseFileName(const std::string& filename,
                           uint64_t* number,
-                          FileType* type);
+                          FileType* type,
+                          WalFileType* log_type = nullptr);
 
 // Make the CURRENT file point to the descriptor file with the
 // specified number.
 extern Status SetCurrentFile(Env* env, const std::string& dbname,
-                             uint64_t descriptor_number);
+                             uint64_t descriptor_number,
+                             Directory* directory_to_fsync);
 
+// Make the IDENTITY file for the db
+extern Status SetIdentityFile(Env* env, const std::string& dbname);
 
 }  // namespace rocksdb
-
-#endif  // STORAGE_LEVELDB_DB_FILENAME_H_

db/filename_test.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -103,7 +108,9 @@ TEST(FileNameTest, Construction) {
   ASSERT_EQ(192U, number);
   ASSERT_EQ(kLogFile, type);
 
-  fname = TableFileName("bar", 200);
+  fname = TableFileName({"bar"}, 200, 0);
+  std::string fname1 = TableFileName({"foo", "bar"}, 200, 1);
+  ASSERT_EQ(fname, fname1);
   ASSERT_EQ("bar/", std::string(fname.data(), 4));
   ASSERT_TRUE(ParseFileName(fname.c_str() + 4, &number, &type));
   ASSERT_EQ(200U, number);

db/forward_iterator.cc

@@ -0,0 +1,460 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+
+#ifndef ROCKSDB_LITE
+#include "db/forward_iterator.h"
+
+#include <string>
+#include <utility>
+#include <limits>
+#include "db/db_impl.h"
+#include "db/db_iter.h"
+#include "db/column_family.h"
+#include "rocksdb/env.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/slice_transform.h"
+#include "table/merger.h"
+#include "db/dbformat.h"
+
+namespace rocksdb {
+
+// Usage:
+//     LevelIterator iter;
+//     iter.SetFileIndex(file_index);
+//     iter.Seek(target);
+//     iter.Next()
+class LevelIterator : public Iterator {
+ public:
+  LevelIterator(const ColumnFamilyData* const cfd,
+      const ReadOptions& read_options,
+      const std::vector<FileMetaData*>& files)
+    : cfd_(cfd), read_options_(read_options), files_(files), valid_(false),
+      file_index_(std::numeric_limits<uint32_t>::max()) {}
+
+  void SetFileIndex(uint32_t file_index) {
+    assert(file_index < files_.size());
+    if (file_index != file_index_) {
+      file_index_ = file_index;
+      file_iter_.reset(cfd_->table_cache()->NewIterator(
+          read_options_, *(cfd_->soptions()), cfd_->internal_comparator(),
+          files_[file_index_]->fd, nullptr /* table_reader_ptr */, false));
+    }
+    valid_ = false;
+  }
+  void SeekToLast() override {
+    status_ = Status::NotSupported("LevelIterator::SeekToLast()");
+    valid_ = false;
+  }
+  void Prev() {
+    status_ = Status::NotSupported("LevelIterator::Prev()");
+    valid_ = false;
+  }
+  bool Valid() const override {
+    return valid_;
+  }
+  void SeekToFirst() override {
+    SetFileIndex(0);
+    file_iter_->SeekToFirst();
+    valid_ = file_iter_->Valid();
+  }
+  void Seek(const Slice& internal_key) override {
+    assert(file_iter_ != nullptr);
+    file_iter_->Seek(internal_key);
+    valid_ = file_iter_->Valid();
+    assert(valid_);
+  }
+  void Next() override {
+    assert(valid_);
+    file_iter_->Next();
+    while (!file_iter_->Valid()) {
+      if (file_index_ + 1 >= files_.size()) {
+        valid_ = false;
+        return;
+      }
+      SetFileIndex(file_index_ + 1);
+      file_iter_->SeekToFirst();
+    }
+    valid_ = file_iter_->Valid();
+  }
+  Slice key() const override {
+    assert(valid_);
+    return file_iter_->key();
+  }
+  Slice value() const override {
+    assert(valid_);
+    return file_iter_->value();
+  }
+  Status status() const override {
+    if (!status_.ok()) {
+      return status_;
+    } else if (file_iter_ && !file_iter_->status().ok()) {
+      return file_iter_->status();
+    }
+    return Status::OK();
+  }
+
+ private:
+  const ColumnFamilyData* const cfd_;
+  const ReadOptions& read_options_;
+  const std::vector<FileMetaData*>& files_;
+
+  bool valid_;
+  uint32_t file_index_;
+  Status status_;
+  std::unique_ptr<Iterator> file_iter_;
+};
+
+ForwardIterator::ForwardIterator(DBImpl* db, const ReadOptions& read_options,
+                                 ColumnFamilyData* cfd)
+    : db_(db),
+      read_options_(read_options),
+      cfd_(cfd),
+      prefix_extractor_(cfd->options()->prefix_extractor.get()),
+      user_comparator_(cfd->user_comparator()),
+      immutable_min_heap_(MinIterComparator(&cfd_->internal_comparator())),
+      sv_(nullptr),
+      mutable_iter_(nullptr),
+      current_(nullptr),
+      valid_(false),
+      is_prev_set_(false) {}
+
+ForwardIterator::~ForwardIterator() {
+  Cleanup();
+}
+
+void ForwardIterator::Cleanup() {
+  delete mutable_iter_;
+  for (auto* m : imm_iters_) {
+    delete m;
+  }
+  imm_iters_.clear();
+  for (auto* f : l0_iters_) {
+    delete f;
+  }
+  l0_iters_.clear();
+  for (auto* l : level_iters_) {
+    delete l;
+  }
+  level_iters_.clear();
+
+  if (sv_ != nullptr && sv_->Unref()) {
+    DBImpl::DeletionState deletion_state;
+    db_->mutex_.Lock();
+    sv_->Cleanup();
+    db_->FindObsoleteFiles(deletion_state, false, true);
+    db_->mutex_.Unlock();
+    delete sv_;
+    if (deletion_state.HaveSomethingToDelete()) {
+      db_->PurgeObsoleteFiles(deletion_state);
+    }
+  }
+}
+
+bool ForwardIterator::Valid() const {
+  return valid_;
+}
+
+void ForwardIterator::SeekToFirst() {
+  if (sv_ == nullptr ||
+      sv_ ->version_number != cfd_->GetSuperVersionNumber()) {
+    RebuildIterators();
+  }
+  SeekInternal(Slice(), true);
+}
+
+void ForwardIterator::Seek(const Slice& internal_key) {
+  if (sv_ == nullptr ||
+      sv_ ->version_number != cfd_->GetSuperVersionNumber()) {
+    RebuildIterators();
+  }
+  SeekInternal(internal_key, false);
+}
+
+void ForwardIterator::SeekInternal(const Slice& internal_key,
+                                   bool seek_to_first) {
+  // mutable
+  seek_to_first ? mutable_iter_->SeekToFirst() :
+                  mutable_iter_->Seek(internal_key);
+
+  // immutable
+  // TODO(ljin): NeedToSeekImmutable has negative impact on performance
+  // if it turns to need to seek immutable often. We probably want to have
+  // an option to turn it off.
+  if (seek_to_first || NeedToSeekImmutable(internal_key)) {
+    {
+      auto tmp = MinIterHeap(MinIterComparator(&cfd_->internal_comparator()));
+      immutable_min_heap_.swap(tmp);
+    }
+    for (auto* m : imm_iters_) {
+      seek_to_first ? m->SeekToFirst() : m->Seek(internal_key);
+      if (m->Valid()) {
+        immutable_min_heap_.push(m);
+      }
+    }
+
+    Slice user_key;
+    if (!seek_to_first) {
+      user_key = ExtractUserKey(internal_key);
+    }
+    auto* files = sv_->current->files_;
+    for (uint32_t i = 0; i < files[0].size(); ++i) {
+      if (seek_to_first) {
+        l0_iters_[i]->SeekToFirst();
+      } else {
+        // If the target key passes over the larget key, we are sure Next()
+        // won't go over this file.
+        if (user_comparator_->Compare(user_key,
+              files[0][i]->largest.user_key()) > 0) {
+          continue;
+        }
+        l0_iters_[i]->Seek(internal_key);
+      }
+      if (l0_iters_[i]->Valid()) {
+        immutable_min_heap_.push(l0_iters_[i]);
+      }
+    }
+
+    int32_t search_left_bound = 0;
+    int32_t search_right_bound = FileIndexer::kLevelMaxIndex;
+    for (int32_t level = 1; level < sv_->current->NumberLevels(); ++level) {
+      if (files[level].empty()) {
+        search_left_bound = 0;
+        search_right_bound = FileIndexer::kLevelMaxIndex;
+        continue;
+      }
+      assert(level_iters_[level - 1] != nullptr);
+      uint32_t f_idx = 0;
+      if (!seek_to_first) {
+        // TODO(ljin): remove before committing
+        // f_idx = FindFileInRange(
+        //    files[level], internal_key, 0, files[level].size());
+
+        if (search_left_bound == search_right_bound) {
+          f_idx = search_left_bound;
+        } else if (search_left_bound < search_right_bound) {
+          f_idx = FindFileInRange(
+              files[level], internal_key, search_left_bound,
+              search_right_bound == FileIndexer::kLevelMaxIndex ?
+                files[level].size() : search_right_bound);
+        } else {
+          // search_left_bound > search_right_bound
+          // There are only 2 cases this can happen:
+          // (1) target key is smaller than left most file
+          // (2) target key is larger than right most file
+          assert(search_left_bound == (int32_t)files[level].size() ||
+                 search_right_bound == -1);
+          if (search_right_bound == -1) {
+            assert(search_left_bound == 0);
+            f_idx = 0;
+          } else {
+            sv_->current->file_indexer_.GetNextLevelIndex(
+                level, files[level].size() - 1,
+                1, 1, &search_left_bound, &search_right_bound);
+            continue;
+          }
+        }
+
+        // Prepare hints for the next level
+        if (f_idx < files[level].size()) {
+          int cmp_smallest = user_comparator_->Compare(
+              user_key, files[level][f_idx]->smallest.user_key());
+          int cmp_largest = -1;
+          if (cmp_smallest >= 0) {
+            cmp_smallest = user_comparator_->Compare(
+                user_key, files[level][f_idx]->smallest.user_key());
+          }
+          sv_->current->file_indexer_.GetNextLevelIndex(level, f_idx,
+              cmp_smallest, cmp_largest,
+              &search_left_bound, &search_right_bound);
+        } else {
+          sv_->current->file_indexer_.GetNextLevelIndex(
+              level, files[level].size() - 1,
+              1, 1, &search_left_bound, &search_right_bound);
+        }
+      }
+
+      // Seek
+      if (f_idx < files[level].size()) {
+        level_iters_[level - 1]->SetFileIndex(f_idx);
+        seek_to_first ? level_iters_[level - 1]->SeekToFirst() :
+                        level_iters_[level - 1]->Seek(internal_key);
+        if (level_iters_[level - 1]->Valid()) {
+          immutable_min_heap_.push(level_iters_[level - 1]);
+        }
+      }
+    }
+
+    if (seek_to_first || immutable_min_heap_.empty()) {
+      is_prev_set_ = false;
+    } else {
+      prev_key_.SetKey(internal_key);
+      is_prev_set_ = true;
+    }
+  }
+
+  UpdateCurrent();
+}
+
+void ForwardIterator::Next() {
+  assert(valid_);
+
+  if (sv_ == nullptr ||
+      sv_ ->version_number != cfd_->GetSuperVersionNumber()) {
+    std::string current_key = key().ToString();
+    Slice old_key(current_key.data(), current_key.size());
+
+    RebuildIterators();
+    SeekInternal(old_key, false);
+    if (!valid_ || key().compare(old_key) != 0) {
+      return;
+    }
+  } else if (current_ != mutable_iter_) {
+    // It is going to advance immutable iterator
+    prev_key_.SetKey(current_->key());
+    is_prev_set_ = true;
+  }
+
+  current_->Next();
+  if (current_->Valid() && current_ != mutable_iter_) {
+    immutable_min_heap_.push(current_);
+  }
+  UpdateCurrent();
+}
+
+Slice ForwardIterator::key() const {
+  assert(valid_);
+  return current_->key();
+}
+
+Slice ForwardIterator::value() const {
+  assert(valid_);
+  return current_->value();
+}
+
+Status ForwardIterator::status() const {
+  if (!status_.ok()) {
+    return status_;
+  } else if (!mutable_iter_->status().ok()) {
+    return mutable_iter_->status();
+  }
+
+  for (auto *it : imm_iters_) {
+    if (it && !it->status().ok()) {
+      return it->status();
+    }
+  }
+  for (auto *it : l0_iters_) {
+    if (it && !it->status().ok()) {
+      return it->status();
+    }
+  }
+  for (auto *it : level_iters_) {
+    if (it && !it->status().ok()) {
+      return it->status();
+    }
+  }
+
+  return Status::OK();
+}
+
+void ForwardIterator::RebuildIterators() {
+  // Clean up
+  Cleanup();
+  // New
+  sv_ = cfd_->GetReferencedSuperVersion(&(db_->mutex_));
+  mutable_iter_ = sv_->mem->NewIterator(read_options_);
+  sv_->imm->AddIterators(read_options_, &imm_iters_);
+  const auto& l0_files = sv_->current->files_[0];
+  l0_iters_.reserve(l0_files.size());
+  for (const auto* l0 : l0_files) {
+    l0_iters_.push_back(cfd_->table_cache()->NewIterator(
+        read_options_, *cfd_->soptions(), cfd_->internal_comparator(), l0->fd));
+  }
+  level_iters_.reserve(sv_->current->NumberLevels() - 1);
+  for (int32_t level = 1; level < sv_->current->NumberLevels(); ++level) {
+    if (sv_->current->files_[level].empty()) {
+      level_iters_.push_back(nullptr);
+    } else {
+      level_iters_.push_back(new LevelIterator(cfd_, read_options_,
+          sv_->current->files_[level]));
+    }
+  }
+
+  current_ = nullptr;
+  is_prev_set_ = false;
+}
+
+void ForwardIterator::UpdateCurrent() {
+  if (immutable_min_heap_.empty() && !mutable_iter_->Valid()) {
+    current_ = nullptr;
+  } else if (immutable_min_heap_.empty()) {
+    current_ = mutable_iter_;
+  } else if (!mutable_iter_->Valid()) {
+    current_ = immutable_min_heap_.top();
+    immutable_min_heap_.pop();
+  } else {
+    current_ = immutable_min_heap_.top();
+    assert(current_ != nullptr);
+    assert(current_->Valid());
+    int cmp = cfd_->internal_comparator().InternalKeyComparator::Compare(
+        mutable_iter_->key(), current_->key());
+    assert(cmp != 0);
+    if (cmp > 0) {
+      immutable_min_heap_.pop();
+    } else {
+      current_ = mutable_iter_;
+    }
+  }
+  valid_ = (current_ != nullptr);
+  if (!status_.ok()) {
+    status_ = Status::OK();
+  }
+}
+
+bool ForwardIterator::NeedToSeekImmutable(const Slice& target) {
+  if (!is_prev_set_) {
+    return true;
+  }
+  Slice prev_key = prev_key_.GetKey();
+  if (prefix_extractor_ && prefix_extractor_->Transform(target).compare(
+    prefix_extractor_->Transform(prev_key)) != 0) {
+    return true;
+  }
+  if (cfd_->internal_comparator().InternalKeyComparator::Compare(
+        prev_key, target) >= 0) {
+    return true;
+  }
+  if (immutable_min_heap_.empty() ||
+      cfd_->internal_comparator().InternalKeyComparator::Compare(
+          target, current_ == mutable_iter_ ? immutable_min_heap_.top()->key()
+                                            : current_->key()) > 0) {
+    return true;
+  }
+  return false;
+}
+
+uint32_t ForwardIterator::FindFileInRange(
+    const std::vector<FileMetaData*>& files, const Slice& internal_key,
+    uint32_t left, uint32_t right) {
+  while (left < right) {
+    uint32_t mid = (left + right) / 2;
+    const FileMetaData* f = files[mid];
+    if (cfd_->internal_comparator().InternalKeyComparator::Compare(
+          f->largest.Encode(), internal_key) < 0) {
+      // Key at "mid.largest" is < "target".  Therefore all
+      // files at or before "mid" are uninteresting.
+      left = mid + 1;
+    } else {
+      // Key at "mid.largest" is >= "target".  Therefore all files
+      // after "mid" are uninteresting.
+      right = mid;
+    }
+  }
+  return right;
+}
+
+}  // namespace rocksdb
+
+#endif  // ROCKSDB_LITE

db/forward_iterator.h

@@ -0,0 +1,105 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+#pragma once
+
+#ifndef ROCKSDB_LITE
+
+#include <string>
+#include <vector>
+#include <queue>
+
+#include "rocksdb/db.h"
+#include "rocksdb/iterator.h"
+#include "rocksdb/options.h"
+#include "db/dbformat.h"
+
+namespace rocksdb {
+
+class DBImpl;
+class Env;
+struct SuperVersion;
+class ColumnFamilyData;
+class LevelIterator;
+struct FileMetaData;
+
+class MinIterComparator {
+ public:
+  explicit MinIterComparator(const Comparator* comparator) :
+    comparator_(comparator) {}
+
+  bool operator()(Iterator* a, Iterator* b) {
+    return comparator_->Compare(a->key(), b->key()) > 0;
+  }
+ private:
+  const Comparator* comparator_;
+};
+
+typedef std::priority_queue<Iterator*,
+          std::vector<Iterator*>,
+          MinIterComparator> MinIterHeap;
+
+/**
+ * ForwardIterator is a special type of iterator that only supports Seek()
+ * and Next(). It is expected to perform better than TailingIterator by
+ * removing the encapsulation and making all information accessible within
+ * the iterator. At the current implementation, snapshot is taken at the
+ * time Seek() is called. The Next() followed do not see new values after.
+ */
+class ForwardIterator : public Iterator {
+ public:
+  ForwardIterator(DBImpl* db, const ReadOptions& read_options,
+                  ColumnFamilyData* cfd);
+  virtual ~ForwardIterator();
+
+  void SeekToLast() override {
+    status_ = Status::NotSupported("ForwardIterator::SeekToLast()");
+    valid_ = false;
+  }
+  void Prev() {
+    status_ = Status::NotSupported("ForwardIterator::Prev");
+    valid_ = false;
+  }
+
+  virtual bool Valid() const override;
+  void SeekToFirst() override;
+  virtual void Seek(const Slice& target) override;
+  virtual void Next() override;
+  virtual Slice key() const override;
+  virtual Slice value() const override;
+  virtual Status status() const override;
+
+ private:
+  void Cleanup();
+  void RebuildIterators();
+  void SeekInternal(const Slice& internal_key, bool seek_to_first);
+  void UpdateCurrent();
+  bool NeedToSeekImmutable(const Slice& internal_key);
+  uint32_t FindFileInRange(
+    const std::vector<FileMetaData*>& files, const Slice& internal_key,
+    uint32_t left, uint32_t right);
+
+  DBImpl* const db_;
+  const ReadOptions read_options_;
+  ColumnFamilyData* const cfd_;
+  const SliceTransform* const prefix_extractor_;
+  const Comparator* user_comparator_;
+  MinIterHeap immutable_min_heap_;
+
+  SuperVersion* sv_;
+  Iterator* mutable_iter_;
+  std::vector<Iterator*> imm_iters_;
+  std::vector<Iterator*> l0_iters_;
+  std::vector<LevelIterator*> level_iters_;
+  Iterator* current_;
+  // internal iterator status
+  Status status_;
+  bool valid_;
+
+  IterKey prev_key_;
+  bool is_prev_set_;
+};
+
+}  // namespace rocksdb
+#endif  // ROCKSDB_LITE

db/internal_stats.cc

@@ -0,0 +1,369 @@
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "db/internal_stats.h"
+#include "db/column_family.h"
+
+#include <vector>
+
+namespace rocksdb {
+
+DBPropertyType GetPropertyType(const Slice& property) {
+  Slice in = property;
+  Slice prefix("rocksdb.");
+  if (!in.starts_with(prefix)) return kUnknown;
+  in.remove_prefix(prefix.size());
+
+  if (in.starts_with("num-files-at-level")) {
+    return kNumFilesAtLevel;
+  } else if (in == "levelstats") {
+    return kLevelStats;
+  } else if (in == "stats") {
+    return kStats;
+  } else if (in == "sstables") {
+    return kSsTables;
+  } else if (in == "num-immutable-mem-table") {
+    return kNumImmutableMemTable;
+  } else if (in == "mem-table-flush-pending") {
+    return kMemtableFlushPending;
+  } else if (in == "compaction-pending") {
+    return kCompactionPending;
+  } else if (in == "background-errors") {
+    return kBackgroundErrors;
+  } else if (in == "cur-size-active-mem-table") {
+    return kCurSizeActiveMemTable;
+  } else if (in == "num-entries-active-mem-table") {
+    return kNumEntriesInMutableMemtable;
+  } else if (in == "num-entries-imm-mem-tables") {
+    return kNumEntriesInImmutableMemtable;
+  }
+  return kUnknown;
+}
+
+bool InternalStats::GetProperty(DBPropertyType property_type,
+                                const Slice& property, std::string* value,
+                                ColumnFamilyData* cfd) {
+  Version* current = cfd->current();
+  Slice in = property;
+
+  switch (property_type) {
+    case kNumFilesAtLevel: {
+      in.remove_prefix(strlen("rocksdb.num-files-at-level"));
+      uint64_t level;
+      bool ok = ConsumeDecimalNumber(&in, &level) && in.empty();
+      if (!ok || (int)level >= number_levels_) {
+        return false;
+      } else {
+        char buf[100];
+        snprintf(buf, sizeof(buf), "%d",
+                 current->NumLevelFiles(static_cast<int>(level)));
+        *value = buf;
+        return true;
+      }
+    }
+    case kLevelStats: {
+      char buf[1000];
+      snprintf(buf, sizeof(buf),
+               "Level Files Size(MB)\n"
+               "--------------------\n");
+      value->append(buf);
+
+      for (int level = 0; level < number_levels_; level++) {
+        snprintf(buf, sizeof(buf), "%3d %8d %8.0f\n", level,
+                 current->NumLevelFiles(level),
+                 current->NumLevelBytes(level) / 1048576.0);
+        value->append(buf);
+      }
+      return true;
+    }
+    case kStats: {
+      char buf[1000];
+
+      uint64_t wal_bytes = 0;
+      uint64_t wal_synced = 0;
+      uint64_t user_bytes_written = 0;
+      uint64_t write_other = 0;
+      uint64_t write_self = 0;
+      uint64_t write_with_wal = 0;
+      uint64_t total_bytes_written = 0;
+      uint64_t total_bytes_read = 0;
+      uint64_t micros_up = env_->NowMicros() - started_at_;
+      // Add "+1" to make sure seconds_up is > 0 and avoid NaN later
+      double seconds_up = (micros_up + 1) / 1000000.0;
+      uint64_t total_slowdown = 0;
+      uint64_t total_slowdown_count = 0;
+      uint64_t interval_bytes_written = 0;
+      uint64_t interval_bytes_read = 0;
+      uint64_t interval_bytes_new = 0;
+      double interval_seconds_up = 0;
+
+      if (statistics_) {
+        wal_bytes = statistics_->getTickerCount(WAL_FILE_BYTES);
+        wal_synced = statistics_->getTickerCount(WAL_FILE_SYNCED);
+        user_bytes_written = statistics_->getTickerCount(BYTES_WRITTEN);
+        write_other = statistics_->getTickerCount(WRITE_DONE_BY_OTHER);
+        write_self = statistics_->getTickerCount(WRITE_DONE_BY_SELF);
+        write_with_wal = statistics_->getTickerCount(WRITE_WITH_WAL);
+      }
+
+      snprintf(
+          buf, sizeof(buf),
+          "                               Compactions\n"
+          "Level  Files Size(MB) Score Time(sec)  Read(MB) Write(MB)    Rn(MB) "
+          " "
+          "Rnp1(MB)  Wnew(MB) RW-Amplify Read(MB/s) Write(MB/s)      Rn     "
+          "Rnp1 "
+          "    Wnp1     NewW    Count   msComp   msStall  Ln-stall Stall-cnt\n"
+          "--------------------------------------------------------------------"
+          "--"
+          "--------------------------------------------------------------------"
+          "--"
+          "----------------------------------------------------------------\n");
+      value->append(buf);
+      for (int level = 0; level < number_levels_; level++) {
+        int files = current->NumLevelFiles(level);
+        if (compaction_stats_[level].micros > 0 || files > 0) {
+          int64_t bytes_read = compaction_stats_[level].bytes_readn +
+                               compaction_stats_[level].bytes_readnp1;
+          int64_t bytes_new = compaction_stats_[level].bytes_written -
+                              compaction_stats_[level].bytes_readnp1;
+          double amplify =
+              (compaction_stats_[level].bytes_readn == 0)
+                  ? 0.0
+                  : (compaction_stats_[level].bytes_written +
+                     compaction_stats_[level].bytes_readnp1 +
+                     compaction_stats_[level].bytes_readn) /
+                        (double)compaction_stats_[level].bytes_readn;
+
+          total_bytes_read += bytes_read;
+          total_bytes_written += compaction_stats_[level].bytes_written;
+
+          uint64_t stalls = level == 0 ? (stall_counts_[LEVEL0_SLOWDOWN] +
+                                          stall_counts_[LEVEL0_NUM_FILES] +
+                                          stall_counts_[MEMTABLE_COMPACTION])
+                                       : stall_leveln_slowdown_count_[level];
+
+          double stall_us = level == 0 ? (stall_micros_[LEVEL0_SLOWDOWN] +
+                                          stall_micros_[LEVEL0_NUM_FILES] +
+                                          stall_micros_[MEMTABLE_COMPACTION])
+                                       : stall_leveln_slowdown_[level];
+
+          snprintf(buf, sizeof(buf),
+                   "%3d %8d %8.0f %5.1f %9.0f %9.0f %9.0f %9.0f %9.0f %9.0f "
+                   "%10.1f %9.1f %11.1f %8d %8d %8d %8d %8d %8d %9.1f %9.1f "
+                   "%9lu\n",
+                   level, files, current->NumLevelBytes(level) / 1048576.0,
+                   current->NumLevelBytes(level) /
+                       cfd->compaction_picker()->MaxBytesForLevel(level),
+                   compaction_stats_[level].micros / 1e6,
+                   bytes_read / 1048576.0,
+                   compaction_stats_[level].bytes_written / 1048576.0,
+                   compaction_stats_[level].bytes_readn / 1048576.0,
+                   compaction_stats_[level].bytes_readnp1 / 1048576.0,
+                   bytes_new / 1048576.0, amplify,
+                   // +1 to avoid division by 0
+                   (bytes_read / 1048576.0) /
+                       ((compaction_stats_[level].micros + 1) / 1000000.0),
+                   (compaction_stats_[level].bytes_written / 1048576.0) /
+                       ((compaction_stats_[level].micros + 1) / 1000000.0),
+                   compaction_stats_[level].files_in_leveln,
+                   compaction_stats_[level].files_in_levelnp1,
+                   compaction_stats_[level].files_out_levelnp1,
+                   compaction_stats_[level].files_out_levelnp1 -
+                       compaction_stats_[level].files_in_levelnp1,
+                   compaction_stats_[level].count,
+                   (int)((double)compaction_stats_[level].micros / 1000.0 /
+                         (compaction_stats_[level].count + 1)),
+                   (double)stall_us / 1000.0 / (stalls + 1),
+                   stall_us / 1000000.0, (unsigned long)stalls);
+          total_slowdown += stall_leveln_slowdown_[level];
+          total_slowdown_count += stall_leveln_slowdown_count_[level];
+          value->append(buf);
+        }
+      }
+
+      interval_bytes_new = user_bytes_written - last_stats_.ingest_bytes_;
+      interval_bytes_read =
+          total_bytes_read - last_stats_.compaction_bytes_read_;
+      interval_bytes_written =
+          total_bytes_written - last_stats_.compaction_bytes_written_;
+      interval_seconds_up = seconds_up - last_stats_.seconds_up_;
+
+      snprintf(buf, sizeof(buf), "Uptime(secs): %.1f total, %.1f interval\n",
+               seconds_up, interval_seconds_up);
+      value->append(buf);
+
+      snprintf(buf, sizeof(buf),
+               "Writes cumulative: %llu total, %llu batches, "
+               "%.1f per batch, %.2f ingest GB\n",
+               (unsigned long long)(write_other + write_self),
+               (unsigned long long)write_self,
+               (write_other + write_self) / (double)(write_self + 1),
+               user_bytes_written / (1048576.0 * 1024));
+      value->append(buf);
+
+      snprintf(buf, sizeof(buf),
+               "WAL cumulative: %llu WAL writes, %llu WAL syncs, "
+               "%.2f writes per sync, %.2f GB written\n",
+               (unsigned long long)write_with_wal,
+               (unsigned long long)wal_synced,
+               write_with_wal / (double)(wal_synced + 1),
+               wal_bytes / (1048576.0 * 1024));
+      value->append(buf);
+
+      snprintf(buf, sizeof(buf),
+               "Compaction IO cumulative (GB): "
+               "%.2f new, %.2f read, %.2f write, %.2f read+write\n",
+               user_bytes_written / (1048576.0 * 1024),
+               total_bytes_read / (1048576.0 * 1024),
+               total_bytes_written / (1048576.0 * 1024),
+               (total_bytes_read + total_bytes_written) / (1048576.0 * 1024));
+      value->append(buf);
+
+      snprintf(
+          buf, sizeof(buf),
+          "Compaction IO cumulative (MB/sec): "
+          "%.1f new, %.1f read, %.1f write, %.1f read+write\n",
+          user_bytes_written / 1048576.0 / seconds_up,
+          total_bytes_read / 1048576.0 / seconds_up,
+          total_bytes_written / 1048576.0 / seconds_up,
+          (total_bytes_read + total_bytes_written) / 1048576.0 / seconds_up);
+      value->append(buf);
+
+      // +1 to avoid divide by 0 and NaN
+      snprintf(
+          buf, sizeof(buf),
+          "Amplification cumulative: %.1f write, %.1f compaction\n",
+          (double)(total_bytes_written + wal_bytes) / (user_bytes_written + 1),
+          (double)(total_bytes_written + total_bytes_read + wal_bytes) /
+              (user_bytes_written + 1));
+      value->append(buf);
+
+      uint64_t interval_write_other = write_other - last_stats_.write_other_;
+      uint64_t interval_write_self = write_self - last_stats_.write_self_;
+
+      snprintf(buf, sizeof(buf),
+               "Writes interval: %llu total, %llu batches, "
+               "%.1f per batch, %.1f ingest MB\n",
+               (unsigned long long)(interval_write_other + interval_write_self),
+               (unsigned long long)interval_write_self,
+               (double)(interval_write_other + interval_write_self) /
+                   (interval_write_self + 1),
+               (user_bytes_written - last_stats_.ingest_bytes_) / 1048576.0);
+      value->append(buf);
+
+      uint64_t interval_write_with_wal =
+          write_with_wal - last_stats_.write_with_wal_;
+
+      uint64_t interval_wal_synced = wal_synced - last_stats_.wal_synced_;
+      uint64_t interval_wal_bytes = wal_bytes - last_stats_.wal_bytes_;
+
+      snprintf(buf, sizeof(buf),
+               "WAL interval: %llu WAL writes, %llu WAL syncs, "
+               "%.2f writes per sync, %.2f MB written\n",
+               (unsigned long long)interval_write_with_wal,
+               (unsigned long long)interval_wal_synced,
+               interval_write_with_wal / (double)(interval_wal_synced + 1),
+               interval_wal_bytes / (1048576.0 * 1024));
+      value->append(buf);
+
+      snprintf(buf, sizeof(buf),
+               "Compaction IO interval (MB): "
+               "%.2f new, %.2f read, %.2f write, %.2f read+write\n",
+               interval_bytes_new / 1048576.0, interval_bytes_read / 1048576.0,
+               interval_bytes_written / 1048576.0,
+               (interval_bytes_read + interval_bytes_written) / 1048576.0);
+      value->append(buf);
+
+      snprintf(buf, sizeof(buf),
+               "Compaction IO interval (MB/sec): "
+               "%.1f new, %.1f read, %.1f write, %.1f read+write\n",
+               interval_bytes_new / 1048576.0 / interval_seconds_up,
+               interval_bytes_read / 1048576.0 / interval_seconds_up,
+               interval_bytes_written / 1048576.0 / interval_seconds_up,
+               (interval_bytes_read + interval_bytes_written) / 1048576.0 /
+                   interval_seconds_up);
+      value->append(buf);
+
+      // +1 to avoid divide by 0 and NaN
+      snprintf(
+          buf, sizeof(buf),
+          "Amplification interval: %.1f write, %.1f compaction\n",
+          (double)(interval_bytes_written + interval_wal_bytes) /
+              (interval_bytes_new + 1),
+          (double)(interval_bytes_written + interval_bytes_read + interval_wal_bytes) /
+              (interval_bytes_new + 1));
+      value->append(buf);
+
+      snprintf(buf, sizeof(buf),
+               "Stalls(secs): %.3f level0_slowdown, %.3f level0_numfiles, "
+               "%.3f memtable_compaction, %.3f leveln_slowdown\n",
+               stall_micros_[LEVEL0_SLOWDOWN] / 1000000.0,
+               stall_micros_[LEVEL0_NUM_FILES] / 1000000.0,
+               stall_micros_[MEMTABLE_COMPACTION] / 1000000.0,
+               total_slowdown / 1000000.0);
+      value->append(buf);
+
+      snprintf(buf, sizeof(buf),
+               "Stalls(count): %lu level0_slowdown, %lu level0_numfiles, "
+               "%lu memtable_compaction, %lu leveln_slowdown\n",
+               (unsigned long)stall_counts_[LEVEL0_SLOWDOWN],
+               (unsigned long)stall_counts_[LEVEL0_NUM_FILES],
+               (unsigned long)stall_counts_[MEMTABLE_COMPACTION],
+               (unsigned long)total_slowdown_count);
+      value->append(buf);
+
+      last_stats_.compaction_bytes_read_ = total_bytes_read;
+      last_stats_.compaction_bytes_written_ = total_bytes_written;
+      last_stats_.ingest_bytes_ = user_bytes_written;
+      last_stats_.seconds_up_ = seconds_up;
+      last_stats_.wal_bytes_ = wal_bytes;
+      last_stats_.wal_synced_ = wal_synced;
+      last_stats_.write_with_wal_ = write_with_wal;
+      last_stats_.write_other_ = write_other;
+      last_stats_.write_self_ = write_self;
+
+      return true;
+    }
+    case kSsTables:
+      *value = current->DebugString();
+      return true;
+    case kNumImmutableMemTable:
+      *value = std::to_string(cfd->imm()->size());
+      return true;
+    case kMemtableFlushPending:
+      // Return number of mem tables that are ready to flush (made immutable)
+      *value = std::to_string(cfd->imm()->IsFlushPending() ? 1 : 0);
+      return true;
+    case kCompactionPending:
+      // 1 if the system already determines at least one compacdtion is needed.
+      // 0 otherwise,
+      *value = std::to_string(current->NeedsCompaction() ? 1 : 0);
+      return true;
+    case kBackgroundErrors:
+      // Accumulated number of  errors in background flushes or compactions.
+      *value = std::to_string(GetBackgroundErrorCount());
+      return true;
+    case kCurSizeActiveMemTable:
+      // Current size of the active memtable
+      *value = std::to_string(cfd->mem()->ApproximateMemoryUsage());
+      return true;
+    case kNumEntriesInMutableMemtable:
+      // Current size of the active memtable
+      *value = std::to_string(cfd->mem()->GetNumEntries());
+      return true;
+    case kNumEntriesInImmutableMemtable:
+      // Current size of the active memtable
+      *value = std::to_string(cfd->imm()->current()->GetTotalNumEntries());
+      return true;
+    default:
+      return false;
+  }
+}
+
+}  // namespace rocksdb

db/internal_stats.h

@@ -0,0 +1,187 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//
+
+#pragma once
+#include "rocksdb/statistics.h"
+#include "util/statistics.h"
+#include "db/version_set.h"
+
+#include <vector>
+#include <string>
+
+class ColumnFamilyData;
+
+namespace rocksdb {
+
+class MemTableList;
+class DBImpl;
+
+enum DBPropertyType {
+  kNumFilesAtLevel,  // Number of files at a specific level
+  kLevelStats,       // Return number of files and total sizes of each level
+  kStats,            // Return general statitistics of DB
+  kSsTables,         // Return a human readable string of current SST files
+  kNumImmutableMemTable,   // Return number of immutable mem tables
+  kMemtableFlushPending,   // Return 1 if mem table flushing is pending,
+                           // otherwise 0.
+  kCompactionPending,      // Return 1 if a compaction is pending. Otherwise 0.
+  kBackgroundErrors,       // Return accumulated background errors encountered.
+  kCurSizeActiveMemTable,  // Return current size of the active memtable
+  kNumEntriesInMutableMemtable,    // Return number of entries in the mutable
+                                   // memtable.
+  kNumEntriesInImmutableMemtable,  // Return sum of number of entries in all
+                                   // the immutable mem tables.
+  kUnknown,
+};
+
+extern DBPropertyType GetPropertyType(const Slice& property);
+
+class InternalStats {
+ public:
+  enum WriteStallType {
+    LEVEL0_SLOWDOWN,
+    MEMTABLE_COMPACTION,
+    LEVEL0_NUM_FILES,
+    WRITE_STALLS_ENUM_MAX,
+  };
+
+  InternalStats(int num_levels, Env* env, Statistics* statistics)
+      : compaction_stats_(num_levels),
+        stall_micros_(WRITE_STALLS_ENUM_MAX, 0),
+        stall_counts_(WRITE_STALLS_ENUM_MAX, 0),
+        stall_leveln_slowdown_(num_levels, 0),
+        stall_leveln_slowdown_count_(num_levels, 0),
+        bg_error_count_(0),
+        number_levels_(num_levels),
+        statistics_(statistics),
+        env_(env),
+        started_at_(env->NowMicros()) {}
+
+  // Per level compaction stats.  compaction_stats_[level] stores the stats for
+  // compactions that produced data for the specified "level".
+  struct CompactionStats {
+    uint64_t micros;
+
+    // Bytes read from level N during compaction between levels N and N+1
+    int64_t bytes_readn;
+
+    // Bytes read from level N+1 during compaction between levels N and N+1
+    int64_t bytes_readnp1;
+
+    // Total bytes written during compaction between levels N and N+1
+    int64_t bytes_written;
+
+    // Files read from level N during compaction between levels N and N+1
+    int files_in_leveln;
+
+    // Files read from level N+1 during compaction between levels N and N+1
+    int files_in_levelnp1;
+
+    // Files written during compaction between levels N and N+1
+    int files_out_levelnp1;
+
+    // Number of compactions done
+    int count;
+
+    CompactionStats()
+        : micros(0),
+          bytes_readn(0),
+          bytes_readnp1(0),
+          bytes_written(0),
+          files_in_leveln(0),
+          files_in_levelnp1(0),
+          files_out_levelnp1(0),
+          count(0) {}
+
+    void Add(const CompactionStats& c) {
+      this->micros += c.micros;
+      this->bytes_readn += c.bytes_readn;
+      this->bytes_readnp1 += c.bytes_readnp1;
+      this->bytes_written += c.bytes_written;
+      this->files_in_leveln += c.files_in_leveln;
+      this->files_in_levelnp1 += c.files_in_levelnp1;
+      this->files_out_levelnp1 += c.files_out_levelnp1;
+      this->count += 1;
+    }
+  };
+
+  void AddCompactionStats(int level, const CompactionStats& stats) {
+    compaction_stats_[level].Add(stats);
+  }
+
+  void RecordWriteStall(WriteStallType write_stall_type, uint64_t micros) {
+    stall_micros_[write_stall_type] += micros;
+    ++stall_counts_[write_stall_type];
+  }
+
+  void RecordLevelNSlowdown(int level, uint64_t micros) {
+    stall_leveln_slowdown_[level] += micros;
+    ++stall_leveln_slowdown_count_[level];
+  }
+
+  uint64_t GetBackgroundErrorCount() const { return bg_error_count_; }
+
+  uint64_t BumpAndGetBackgroundErrorCount() { return ++bg_error_count_; }
+
+  bool GetProperty(DBPropertyType property_type, const Slice& property,
+                   std::string* value, ColumnFamilyData* cfd);
+
+ private:
+  std::vector<CompactionStats> compaction_stats_;
+
+  // Used to compute per-interval statistics
+  struct StatsSnapshot {
+    uint64_t compaction_bytes_read_;     // Bytes read by compaction
+    uint64_t compaction_bytes_written_;  // Bytes written by compaction
+    uint64_t ingest_bytes_;              // Bytes written by user
+    uint64_t wal_bytes_;                 // Bytes written to WAL
+    uint64_t wal_synced_;                // Number of times WAL is synced
+    uint64_t write_with_wal_;            // Number of writes that request WAL
+    // These count the number of writes processed by the calling thread or
+    // another thread.
+    uint64_t write_other_;
+    uint64_t write_self_;
+    double seconds_up_;
+
+    StatsSnapshot()
+        : compaction_bytes_read_(0),
+          compaction_bytes_written_(0),
+          ingest_bytes_(0),
+          wal_bytes_(0),
+          wal_synced_(0),
+          write_with_wal_(0),
+          write_other_(0),
+          write_self_(0),
+          seconds_up_(0) {}
+  };
+
+  // Counters from the previous time per-interval stats were computed
+  StatsSnapshot last_stats_;
+
+  // These count the number of microseconds for which MakeRoomForWrite stalls.
+  std::vector<uint64_t> stall_micros_;
+  std::vector<uint64_t> stall_counts_;
+  std::vector<uint64_t> stall_leveln_slowdown_;
+  std::vector<uint64_t> stall_leveln_slowdown_count_;
+
+  // Total number of background errors encountered. Every time a flush task
+  // or compaction task fails, this counter is incremented. The failure can
+  // be caused by any possible reason, including file system errors, out of
+  // resources, or input file corruption. Failing when retrying the same flush
+  // or compaction will cause the counter to increase too.
+  uint64_t bg_error_count_;
+
+  int number_levels_;
+  Statistics* statistics_;
+  Env* env_;
+  uint64_t started_at_;
+};
+
+}  // namespace rocksdb

db/log_and_apply_bench.cc

@@ -0,0 +1,79 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+
+
+#include <vector>
+
+#include "util/testharness.h"
+#include "util/benchharness.h"
+#include "db/version_set.h"
+#include "util/mutexlock.h"
+
+namespace rocksdb {
+
+std::string MakeKey(unsigned int num) {
+  char buf[30];
+  snprintf(buf, sizeof(buf), "%016u", num);
+  return std::string(buf);
+}
+
+void BM_LogAndApply(int iters, int num_base_files) {
+  VersionSet* vset;
+  ColumnFamilyData* default_cfd;
+  uint64_t fnum = 1;
+  port::Mutex mu;
+  MutexLock l(&mu);
+
+  BENCHMARK_SUSPEND {
+    std::string dbname = test::TmpDir() + "/rocksdb_test_benchmark";
+    ASSERT_OK(DestroyDB(dbname, Options()));
+
+    DB* db = nullptr;
+    Options opts;
+    opts.create_if_missing = true;
+    Status s = DB::Open(opts, dbname, &db);
+    ASSERT_OK(s);
+    ASSERT_TRUE(db != nullptr);
+
+    delete db;
+    db = nullptr;
+
+    Options options;
+    EnvOptions sopt;
+    vset = new VersionSet(dbname, &options, sopt, nullptr);
+    std::vector<ColumnFamilyDescriptor> dummy;
+    dummy.push_back(ColumnFamilyDescriptor());
+    ASSERT_OK(vset->Recover(dummy));
+    default_cfd = vset->GetColumnFamilySet()->GetDefault();
+    VersionEdit vbase;
+    for (int i = 0; i < num_base_files; i++) {
+      InternalKey start(MakeKey(2 * fnum), 1, kTypeValue);
+      InternalKey limit(MakeKey(2 * fnum + 1), 1, kTypeDeletion);
+      vbase.AddFile(2, ++fnum, 0, 1 /* file size */, start, limit, 1, 1);
+    }
+    ASSERT_OK(vset->LogAndApply(default_cfd, &vbase, &mu));
+  }
+
+  for (int i = 0; i < iters; i++) {
+    VersionEdit vedit;
+    vedit.DeleteFile(2, fnum);
+    InternalKey start(MakeKey(2 * fnum), 1, kTypeValue);
+    InternalKey limit(MakeKey(2 * fnum + 1), 1, kTypeDeletion);
+    vedit.AddFile(2, ++fnum, 0, 1 /* file size */, start, limit, 1, 1);
+    vset->LogAndApply(default_cfd, &vedit, &mu);
+  }
+}
+
+BENCHMARK_NAMED_PARAM(BM_LogAndApply, 1000_iters_1_file, 1000, 1)
+BENCHMARK_NAMED_PARAM(BM_LogAndApply, 1000_iters_100_files, 1000, 100)
+BENCHMARK_NAMED_PARAM(BM_LogAndApply, 1000_iters_10000_files, 1000, 10000)
+BENCHMARK_NAMED_PARAM(BM_LogAndApply, 100_iters_100000_files, 100, 100000)
+
+}  // namespace rocksdb
+
+int main(int argc, char** argv) {
+  rocksdb::benchmark::RunBenchmarks();
+  return 0;
+}

db/log_format.h

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -5,16 +10,13 @@
 // Log format information shared by reader and writer.
 // See ../doc/log_format.txt for more detail.
 
-#ifndef STORAGE_LEVELDB_DB_LOG_FORMAT_H_
-#define STORAGE_LEVELDB_DB_LOG_FORMAT_H_
-
+#pragma once
 namespace rocksdb {
 namespace log {
 
 enum RecordType {
   // Zero is reserved for preallocated files
   kZeroType = 0,
-
   kFullType = 1,
 
   // For fragments
@@ -31,5 +33,3 @@ static const int kHeaderSize = 4 + 1 + 2;
 
 }  // namespace log
 }  // namespace rocksdb
-
-#endif  // STORAGE_LEVELDB_DB_LOG_FORMAT_H_

db/log_reader.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -23,6 +28,8 @@ Reader::Reader(unique_ptr<SequentialFile>&& file, Reporter* reporter,
       backing_store_(new char[kBlockSize]),
       buffer_(),
       eof_(false),
+      read_error_(false),
+      eof_offset_(0),
       last_record_offset_(0),
       end_of_buffer_offset_(0),
       initial_offset_(initial_offset) {
@@ -133,7 +140,9 @@ bool Reader::ReadRecord(Slice* record, std::string* scratch) {
 
       case kEof:
         if (in_fragmented_record) {
-          ReportCorruption(scratch->size(), "partial record without end(3)");
+          // This can be caused by the writer dying immediately after
+          //  writing a physical record but before completing the next; don't
+          //  treat it as a corruption, just ignore the entire logical record.
           scratch->clear();
         }
         return false;
@@ -165,6 +174,69 @@ uint64_t Reader::LastRecordOffset() {
   return last_record_offset_;
 }
 
+void Reader::UnmarkEOF() {
+  if (read_error_) {
+    return;
+  }
+
+  eof_ = false;
+
+  if (eof_offset_ == 0) {
+    return;
+  }
+
+  // If the EOF was in the middle of a block (a partial block was read) we have
+  // to read the rest of the block as ReadPhysicalRecord can only read full
+  // blocks and expects the file position indicator to be aligned to the start
+  // of a block.
+  //
+  //      consumed_bytes + buffer_size() + remaining == kBlockSize
+
+  size_t consumed_bytes = eof_offset_ - buffer_.size();
+  size_t remaining = kBlockSize - eof_offset_;
+
+  // backing_store_ is used to concatenate what is left in buffer_ and
+  // the remainder of the block. If buffer_ already uses backing_store_,
+  // we just append the new data.
+  if (buffer_.data() != backing_store_ + consumed_bytes) {
+    // Buffer_ does not use backing_store_ for storage.
+    // Copy what is left in buffer_ to backing_store.
+    memmove(backing_store_ + consumed_bytes, buffer_.data(), buffer_.size());
+  }
+
+  Slice read_buffer;
+  Status status = file_->Read(remaining, &read_buffer,
+    backing_store_ + eof_offset_);
+
+  size_t added = read_buffer.size();
+  end_of_buffer_offset_ += added;
+
+  if (!status.ok()) {
+    if (added > 0) {
+      ReportDrop(added, status);
+    }
+
+    read_error_ = true;
+    return;
+  }
+
+  if (read_buffer.data() != backing_store_ + eof_offset_) {
+    // Read did not write to backing_store_
+    memmove(backing_store_ + eof_offset_, read_buffer.data(),
+      read_buffer.size());
+  }
+
+  buffer_ = Slice(backing_store_ + consumed_bytes,
+    eof_offset_ + added - consumed_bytes);
+
+  if (added < remaining) {
+    eof_ = true;
+    eof_offset_ += added;
+  } else {
+    eof_offset_ = 0;
+  }
+}
+
 void Reader::ReportCorruption(size_t bytes, const char* reason) {
   ReportDrop(bytes, Status::Corruption(reason));
 }
@@ -179,7 +251,7 @@ void Reader::ReportDrop(size_t bytes, const Status& reason) {
 unsigned int Reader::ReadPhysicalRecord(Slice* result) {
   while (true) {
     if (buffer_.size() < (size_t)kHeaderSize) {
-      if (!eof_) {
+      if (!eof_ && !read_error_) {
         // Last read was a full read, so this is a trailer to skip
         buffer_.clear();
         Status status = file_->Read(kBlockSize, &buffer_, backing_store_);
@@ -187,19 +259,19 @@ unsigned int Reader::ReadPhysicalRecord(Slice* result) {
         if (!status.ok()) {
           buffer_.clear();
           ReportDrop(kBlockSize, status);
-          eof_ = true;
+          read_error_ = true;
           return kEof;
         } else if (buffer_.size() < (size_t)kBlockSize) {
           eof_ = true;
+          eof_offset_ = buffer_.size();
         }
         continue;
-      } else if (buffer_.size() == 0) {
-        // End of file
-        return kEof;
       } else {
-        size_t drop_size = buffer_.size();
+        // Note that if buffer_ is non-empty, we have a truncated header at the
+        //  end of the file, which can be caused by the writer crashing in the
+        //  middle of writing the header. Instead of considering this an error,
+        //  just report EOF.
         buffer_.clear();
-        ReportCorruption(drop_size, "truncated record at end of file");
         return kEof;
       }
     }
@@ -213,14 +285,22 @@ unsigned int Reader::ReadPhysicalRecord(Slice* result) {
     if (kHeaderSize + length > buffer_.size()) {
       size_t drop_size = buffer_.size();
       buffer_.clear();
-      ReportCorruption(drop_size, "bad record length");
-      return kBadRecord;
+      if (!eof_) {
+        ReportCorruption(drop_size, "bad record length");
+        return kBadRecord;
+      }
+      // If the end of the file has been reached without reading |length| bytes
+      // of payload, assume the writer died in the middle of writing the record.
+      // Don't report a corruption.
+      return kEof;
     }
 
     if (type == kZeroType && length == 0) {
       // Skip zero length record without reporting any drops since
       // such records are produced by the mmap based writing code in
       // env_posix.cc that preallocates file regions.
+      // NOTE: this should never happen in DB written by new RocksDB versions,
+      // since we turn off mmap writes to manifest and log files
       buffer_.clear();
       return kBadRecord;
     }

db/log_reader.h

@@ -1,10 +1,13 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
-#ifndef STORAGE_LEVELDB_DB_LOG_READER_H_
-#define STORAGE_LEVELDB_DB_LOG_READER_H_
-
+#pragma once
 #include <memory>
 #include <stdint.h>
 
@@ -66,9 +69,10 @@ class Reader {
 
   // when we know more data has been written to the file. we can use this
   // function to force the reader to look again in the file.
-  void UnmarkEOF() {
-    eof_ = false;
-  }
+  // Also aligns the file position indicator to the start of the next block
+  // by reading the rest of the data from the EOF position to the end of the
+  // block that was partially read.
+  void UnmarkEOF();
 
   SequentialFile* file() { return file_.get(); }
 
@@ -79,6 +83,11 @@ class Reader {
   char* const backing_store_;
   Slice buffer_;
   bool eof_;   // Last Read() indicated EOF by returning < kBlockSize
+  bool read_error_;   // Error occurred while reading from file
+
+  // Offset of the file position indicator within the last block when an
+  // EOF was detected.
+  size_t eof_offset_;
 
   // Offset of the last record returned by ReadRecord.
   uint64_t last_record_offset_;
@@ -119,5 +128,3 @@ class Reader {
 
 }  // namespace log
 }  // namespace rocksdb
-
-#endif  // STORAGE_LEVELDB_DB_LOG_READER_H_

db/log_test.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -42,36 +47,93 @@ class LogTest {
    public:
     std::string contents_;
 
+    explicit StringDest(Slice& reader_contents) :
+      WritableFile(),
+      contents_(""),
+      reader_contents_(reader_contents),
+      last_flush_(0) {
+      reader_contents_ = Slice(contents_.data(), 0);
+    };
+
     virtual Status Close() { return Status::OK(); }
-    virtual Status Flush() { return Status::OK(); }
+    virtual Status Flush() {
+      ASSERT_TRUE(reader_contents_.size() <= last_flush_);
+      size_t offset = last_flush_ - reader_contents_.size();
+      reader_contents_ = Slice(
+          contents_.data() + offset,
+          contents_.size() - offset);
+      last_flush_ = contents_.size();
+
+      return Status::OK();
+    }
     virtual Status Sync() { return Status::OK(); }
     virtual Status Append(const Slice& slice) {
       contents_.append(slice.data(), slice.size());
       return Status::OK();
     }
+    void Drop(size_t bytes) {
+      contents_.resize(contents_.size() - bytes);
+      reader_contents_ = Slice(
+          reader_contents_.data(), reader_contents_.size() - bytes);
+      last_flush_ = contents_.size();
+    }
+
+   private:
+    Slice& reader_contents_;
+    size_t last_flush_;
   };
 
   class StringSource : public SequentialFile {
    public:
-    Slice contents_;
+    Slice& contents_;
     bool force_error_;
+    size_t force_error_position_;
+    bool force_eof_;
+    size_t force_eof_position_;
     bool returned_partial_;
-    StringSource() : force_error_(false), returned_partial_(false) { }
+    explicit StringSource(Slice& contents) :
+      contents_(contents),
+      force_error_(false),
+      force_error_position_(0),
+      force_eof_(false),
+      force_eof_position_(0),
+      returned_partial_(false) { }
 
     virtual Status Read(size_t n, Slice* result, char* scratch) {
       ASSERT_TRUE(!returned_partial_) << "must not Read() after eof/error";
 
       if (force_error_) {
-        force_error_ = false;
-        returned_partial_ = true;
-        return Status::Corruption("read error");
+        if (force_error_position_ >= n) {
+          force_error_position_ -= n;
+        } else {
+          *result = Slice(contents_.data(), force_error_position_);
+          contents_.remove_prefix(force_error_position_);
+          force_error_ = false;
+          returned_partial_ = true;
+          return Status::Corruption("read error");
+        }
       }
 
       if (contents_.size() < n) {
         n = contents_.size();
         returned_partial_ = true;
       }
-      *result = Slice(contents_.data(), n);
+
+      if (force_eof_) {
+        if (force_eof_position_ >= n) {
+          force_eof_position_ -= n;
+        } else {
+          force_eof_ = false;
+          n = force_eof_position_;
+          returned_partial_ = true;
+        }
+      }
+
+      // By using scratch we ensure that caller has control over the
+      // lifetime of result.data()
+      memcpy(scratch, contents_.data(), n);
+      *result = Slice(scratch, n);
+
       contents_.remove_prefix(n);
       return Status::OK();
     }
@@ -118,10 +180,10 @@ class LogTest {
     src->contents_ = dest_contents();
   }
 
+  Slice reader_contents_;
   unique_ptr<StringDest> dest_holder_;
   unique_ptr<StringSource> source_holder_;
   ReportCollector report_;
-  bool reading_;
   Writer writer_;
   Reader reader_;
 
@@ -130,16 +192,15 @@ class LogTest {
   static uint64_t initial_offset_last_record_offsets_[];
 
  public:
-  LogTest() : dest_holder_(new StringDest),
-              source_holder_(new StringSource),
-              reading_(false),
+  LogTest() : reader_contents_(),
+              dest_holder_(new StringDest(reader_contents_)),
+              source_holder_(new StringSource(reader_contents_)),
               writer_(std::move(dest_holder_)),
               reader_(std::move(source_holder_), &report_, true/*checksum*/,
                       0/*initial_offset*/) {
   }
 
   void Write(const std::string& msg) {
-    ASSERT_TRUE(!reading_) << "Write() after starting to read";
     writer_.AddRecord(Slice(msg));
   }
 
@@ -148,10 +209,6 @@ class LogTest {
   }
 
   std::string Read() {
-    if (!reading_) {
-      reading_ = true;
-      reset_source_contents();
-    }
     std::string scratch;
     Slice record;
     if (reader_.ReadRecord(&record, &scratch)) {
@@ -170,7 +227,9 @@ class LogTest {
   }
 
   void ShrinkSize(int bytes) {
-    dest_contents().resize(dest_contents().size() - bytes);
+    auto dest = dynamic_cast<StringDest*>(writer_.file());
+    assert(dest);
+    dest->Drop(bytes);
   }
 
   void FixChecksum(int header_offset, int len) {
@@ -180,9 +239,10 @@ class LogTest {
     EncodeFixed32(&dest_contents()[header_offset], crc);
   }
 
-  void ForceError() {
+  void ForceError(size_t position = 0) {
     auto src = dynamic_cast<StringSource*>(reader_.file());
     src->force_error_ = true;
+    src->force_error_position_ = position;
   }
 
   size_t DroppedBytes() const {
@@ -193,6 +253,22 @@ class LogTest {
     return report_.message_;
   }
 
+  void ForceEOF(size_t position = 0) {
+    auto src = dynamic_cast<StringSource*>(reader_.file());
+    src->force_eof_ = true;
+    src->force_eof_position_ = position;
+  }
+
+  void UnmarkEOF() {
+    auto src = dynamic_cast<StringSource*>(reader_.file());
+    src->returned_partial_ = false;
+    reader_.UnmarkEOF();
+  }
+
+  bool IsEOF() {
+    return reader_.IsEOF();
+  }
+
   // Returns OK iff recorded error message contains "msg"
   std::string MatchError(const std::string& msg) const {
     if (report_.message_.find(msg) == std::string::npos) {
@@ -212,9 +288,7 @@ class LogTest {
 
   void CheckOffsetPastEndReturnsNoRecords(uint64_t offset_past_end) {
     WriteInitialOffsetLog();
-    reading_ = true;
-    unique_ptr<StringSource> source(new StringSource);
-    source->contents_ = dest_contents();
+    unique_ptr<StringSource> source(new StringSource(reader_contents_));
     unique_ptr<Reader> offset_reader(
       new Reader(std::move(source), &report_, true/*checksum*/,
                  WrittenBytes() + offset_past_end));
@@ -226,9 +300,7 @@ class LogTest {
   void CheckInitialOffsetRecord(uint64_t initial_offset,
                                 int expected_record_offset) {
     WriteInitialOffsetLog();
-    reading_ = true;
-    unique_ptr<StringSource> source(new StringSource);
-    source->contents_ = dest_contents();
+    unique_ptr<StringSource> source(new StringSource(reader_contents_));
     unique_ptr<Reader> offset_reader(
       new Reader(std::move(source), &report_, true/*checksum*/,
                  initial_offset));
@@ -374,20 +446,32 @@ TEST(LogTest, BadRecordType) {
   ASSERT_EQ("OK", MatchError("unknown record type"));
 }
 
-TEST(LogTest, TruncatedTrailingRecord) {
+TEST(LogTest, TruncatedTrailingRecordIsIgnored) {
   Write("foo");
   ShrinkSize(4);   // Drop all payload as well as a header byte
   ASSERT_EQ("EOF", Read());
-  ASSERT_EQ((unsigned int)(kHeaderSize - 1), DroppedBytes());
-  ASSERT_EQ("OK", MatchError("truncated record at end of file"));
+  // Truncated last record is ignored, not treated as an error
+  ASSERT_EQ(0U, DroppedBytes());
+  ASSERT_EQ("", ReportMessage());
 }
 
 TEST(LogTest, BadLength) {
+  const int kPayloadSize = kBlockSize - kHeaderSize;
+  Write(BigString("bar", kPayloadSize));
+  Write("foo");
+  // Least significant size byte is stored in header[4].
+  IncrementByte(4, 1);
+  ASSERT_EQ("foo", Read());
+  ASSERT_EQ(kBlockSize, DroppedBytes());
+  ASSERT_EQ("OK", MatchError("bad record length"));
+}
+
+TEST(LogTest, BadLengthAtEndIsIgnored) {
   Write("foo");
   ShrinkSize(1);
   ASSERT_EQ("EOF", Read());
-  ASSERT_EQ((unsigned int)(kHeaderSize + 2), DroppedBytes());
-  ASSERT_EQ("OK", MatchError("bad record length"));
+  ASSERT_EQ(0U, DroppedBytes());
+  ASSERT_EQ("", ReportMessage());
 }
 
 TEST(LogTest, ChecksumMismatch) {
@@ -438,6 +522,24 @@ TEST(LogTest, UnexpectedFirstType) {
   ASSERT_EQ("OK", MatchError("partial record without end"));
 }
 
+TEST(LogTest, MissingLastIsIgnored) {
+  Write(BigString("bar", kBlockSize));
+  // Remove the LAST block, including header.
+  ShrinkSize(14);
+  ASSERT_EQ("EOF", Read());
+  ASSERT_EQ("", ReportMessage());
+  ASSERT_EQ(0U, DroppedBytes());
+}
+
+TEST(LogTest, PartialLastIsIgnored) {
+  Write(BigString("bar", kBlockSize));
+  // Cause a bad record length in the LAST block.
+  ShrinkSize(1);
+  ASSERT_EQ("EOF", Read());
+  ASSERT_EQ("", ReportMessage());
+  ASSERT_EQ(0U, DroppedBytes());
+}
+
 TEST(LogTest, ErrorJoinsRecords) {
   // Consider two fragmented records:
   //    first(R1) last(R1) first(R2) last(R2)
@@ -515,6 +617,70 @@ TEST(LogTest, ReadPastEnd) {
   CheckOffsetPastEndReturnsNoRecords(5);
 }
 
+TEST(LogTest, ClearEofSingleBlock) {
+  Write("foo");
+  Write("bar");
+  ForceEOF(3 + kHeaderSize + 2);
+  ASSERT_EQ("foo", Read());
+  UnmarkEOF();
+  ASSERT_EQ("bar", Read());
+  ASSERT_TRUE(IsEOF());
+  ASSERT_EQ("EOF", Read());
+  Write("xxx");
+  UnmarkEOF();
+  ASSERT_EQ("xxx", Read());
+  ASSERT_TRUE(IsEOF());
+}
+
+TEST(LogTest, ClearEofMultiBlock) {
+  size_t num_full_blocks = 5;
+  size_t n = (kBlockSize - kHeaderSize) * num_full_blocks + 25;
+  Write(BigString("foo", n));
+  Write(BigString("bar", n));
+  ForceEOF(n + num_full_blocks * kHeaderSize + 10);
+  ASSERT_EQ(BigString("foo", n), Read());
+  ASSERT_TRUE(IsEOF());
+  UnmarkEOF();
+  ASSERT_EQ(BigString("bar", n), Read());
+  ASSERT_TRUE(IsEOF());
+  Write(BigString("xxx", n));
+  UnmarkEOF();
+  ASSERT_EQ(BigString("xxx", n), Read());
+  ASSERT_TRUE(IsEOF());
+}
+
+TEST(LogTest, ClearEofError) {
+  // If an error occurs during Read() in UnmarkEOF(), the records contained
+  // in the buffer should be returned on subsequent calls of ReadRecord()
+  // until no more full records are left, whereafter ReadRecord() should return
+  // false to indicate that it cannot read any further.
+
+  Write("foo");
+  Write("bar");
+  UnmarkEOF();
+  ASSERT_EQ("foo", Read());
+  ASSERT_TRUE(IsEOF());
+  Write("xxx");
+  ForceError(0);
+  UnmarkEOF();
+  ASSERT_EQ("bar", Read());
+  ASSERT_EQ("EOF", Read());
+}
+
+TEST(LogTest, ClearEofError2) {
+  Write("foo");
+  Write("bar");
+  UnmarkEOF();
+  ASSERT_EQ("foo", Read());
+  Write("xxx");
+  ForceError(3);
+  UnmarkEOF();
+  ASSERT_EQ("bar", Read());
+  ASSERT_EQ("EOF", Read());
+  ASSERT_EQ(3U, DroppedBytes());
+  ASSERT_EQ("OK", MatchError("read error"));
+}
+
 }  // namespace log
 }  // namespace rocksdb
 

db/log_writer.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.

db/log_writer.h

@@ -1,10 +1,13 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
-#ifndef STORAGE_LEVELDB_DB_LOG_WRITER_H_
-#define STORAGE_LEVELDB_DB_LOG_WRITER_H_
-
+#pragma once
 #include <memory>
 #include <stdint.h>
 #include "db/log_format.h"
@@ -50,5 +53,3 @@ class Writer {
 
 }  // namespace log
 }  // namespace rocksdb
-
-#endif  // STORAGE_LEVELDB_DB_LOG_WRITER_H_

db/memtable.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -5,48 +10,146 @@
 #include "db/memtable.h"
 
 #include <memory>
+#include <algorithm>
+#include <limits>
 
 #include "db/dbformat.h"
+#include "db/merge_context.h"
 #include "rocksdb/comparator.h"
 #include "rocksdb/env.h"
 #include "rocksdb/iterator.h"
 #include "rocksdb/merge_operator.h"
+#include "rocksdb/slice_transform.h"
+#include "table/merger.h"
+#include "util/arena.h"
 #include "util/coding.h"
 #include "util/murmurhash.h"
+#include "util/mutexlock.h"
+#include "util/perf_context_imp.h"
+#include "util/statistics.h"
+#include "util/stop_watch.h"
 
 namespace rocksdb {
 
-MemTable::MemTable(const InternalKeyComparator& cmp,
-                   std::shared_ptr<MemTableRepFactory> table_factory,
-                   int numlevel,
-                   const Options& options)
+MemTable::MemTable(const InternalKeyComparator& cmp, const Options& options)
     : comparator_(cmp),
       refs_(0),
-      arena_impl_(options.arena_block_size),
-      table_(table_factory->CreateMemTableRep(comparator_, &arena_impl_)),
+      kArenaBlockSize(OptimizeBlockSize(options.arena_block_size)),
+      kWriteBufferSize(options.write_buffer_size),
+      arena_(options.arena_block_size),
+      table_(options.memtable_factory->CreateMemTableRep(
+          comparator_, &arena_, options.prefix_extractor.get(),
+          options.info_log.get())),
+      num_entries_(0),
       flush_in_progress_(false),
       flush_completed_(false),
       file_number_(0),
-      edit_(numlevel),
       first_seqno_(0),
       mem_next_logfile_number_(0),
-      mem_logfile_number_(0) { }
+      locks_(options.inplace_update_support ? options.inplace_update_num_locks
+                                            : 0),
+      prefix_extractor_(options.prefix_extractor.get()),
+      should_flush_(ShouldFlushNow()) {
+  // if should_flush_ == true without an entry inserted, something must have
+  // gone wrong already.
+  assert(!should_flush_);
+  if (prefix_extractor_ && options.memtable_prefix_bloom_bits > 0) {
+    prefix_bloom_.reset(new DynamicBloom(
+        &arena_,
+        options.memtable_prefix_bloom_bits, options.bloom_locality,
+        options.memtable_prefix_bloom_probes, nullptr,
+        options.memtable_prefix_bloom_huge_page_tlb_size,
+        options.info_log.get()));
+  }
+}
 
 MemTable::~MemTable() {
   assert(refs_ == 0);
 }
 
 size_t MemTable::ApproximateMemoryUsage() {
-  return arena_impl_.ApproximateMemoryUsage() +
-    table_->ApproximateMemoryUsage();
+  size_t arena_usage = arena_.ApproximateMemoryUsage();
+  size_t table_usage = table_->ApproximateMemoryUsage();
+  // let MAX_USAGE =  std::numeric_limits<size_t>::max()
+  // then if arena_usage + total_usage >= MAX_USAGE, return MAX_USAGE.
+  // the following variation is to avoid numeric overflow.
+  if (arena_usage >= std::numeric_limits<size_t>::max() - table_usage) {
+    return std::numeric_limits<size_t>::max();
+  }
+  // otherwise, return the actual usage
+  return arena_usage + table_usage;
 }
 
-int MemTable::KeyComparator::operator()(const char* aptr, const char* bptr)
+bool MemTable::ShouldFlushNow() const {
+  // In a lot of times, we cannot allocate arena blocks that exactly matches the
+  // buffer size. Thus we have to decide if we should over-allocate or
+  // under-allocate.
+  // This constant avariable can be interpreted as: if we still have more than
+  // "kAllowOverAllocationRatio * kArenaBlockSize" space left, we'd try to over
+  // allocate one more block.
+  const double kAllowOverAllocationRatio = 0.6;
+
+  // If arena still have room for new block allocation, we can safely say it
+  // shouldn't flush.
+  auto allocated_memory =
+      table_->ApproximateMemoryUsage() + arena_.MemoryAllocatedBytes();
+
+  // if we can still allocate one more block without exceeding the
+  // over-allocation ratio, then we should not flush.
+  if (allocated_memory + kArenaBlockSize <
+      kWriteBufferSize + kArenaBlockSize * kAllowOverAllocationRatio) {
+    return false;
+  }
+
+  // if user keeps adding entries that exceeds kWriteBufferSize, we need to
+  // flush earlier even though we still have much available memory left.
+  if (allocated_memory >
+      kWriteBufferSize + kArenaBlockSize * kAllowOverAllocationRatio) {
+    return true;
+  }
+
+  // In this code path, Arena has already allocated its "last block", which
+  // means the total allocatedmemory size is either:
+  //  (1) "moderately" over allocated the memory (no more than `0.6 * arena
+  // block size`. Or,
+  //  (2) the allocated memory is less than write buffer size, but we'll stop
+  // here since if we allocate a new arena block, we'll over allocate too much
+  // more (half of the arena block size) memory.
+  //
+  // In either case, to avoid over-allocate, the last block will stop allocation
+  // when its usage reaches a certain ratio, which we carefully choose "0.75
+  // full" as the stop condition because it addresses the following issue with
+  // great simplicity: What if the next inserted entry's size is
+  // bigger than AllocatedAndUnused()?
+  //
+  // The answer is: if the entry size is also bigger than 0.25 *
+  // kArenaBlockSize, a dedicated block will be allocated for it; otherwise
+  // arena will anyway skip the AllocatedAndUnused() and allocate a new, empty
+  // and regular block. In either case, we *overly* over-allocated.
+  //
+  // Therefore, setting the last block to be at most "0.75 full" avoids both
+  // cases.
+  //
+  // NOTE: the average percentage of waste space of this approach can be counted
+  // as: "arena block size * 0.25 / write buffer size". User who specify a small
+  // write buffer size and/or big arena block size may suffer.
+  return arena_.AllocatedAndUnused() < kArenaBlockSize / 4;
+}
+
+int MemTable::KeyComparator::operator()(const char* prefix_len_key1,
+                                        const char* prefix_len_key2) const {
+  // Internal keys are encoded as length-prefixed strings.
+  Slice k1 = GetLengthPrefixedSlice(prefix_len_key1);
+  Slice k2 = GetLengthPrefixedSlice(prefix_len_key2);
+  return comparator.Compare(k1, k2);
+}
+
+int MemTable::KeyComparator::operator()(const char* prefix_len_key,
+                                        const Slice& key)
     const {
   // Internal keys are encoded as length-prefixed strings.
-  Slice a = GetLengthPrefixedSlice(aptr);
-  Slice b = GetLengthPrefixedSlice(bptr);
-  return comparator.Compare(a, b);
+  Slice a = GetLengthPrefixedSlice(prefix_len_key);
+  return comparator.Compare(a, key);
 }
 
 Slice MemTableRep::UserKey(const char* key) const {
@@ -54,10 +157,15 @@ Slice MemTableRep::UserKey(const char* key) const {
   return Slice(slice.data(), slice.size() - 8);
 }
 
+KeyHandle MemTableRep::Allocate(const size_t len, char** buf) {
+  *buf = arena_->Allocate(len);
+  return static_cast<KeyHandle>(*buf);
+}
+
 // Encode a suitable internal key target for "target" and return it.
 // Uses *scratch as scratch space, and the returned pointer will point
 // into this scratch space.
-static const char* EncodeKey(std::string* scratch, const Slice& target) {
+const char* EncodeKey(std::string* scratch, const Slice& target) {
   scratch->clear();
   PutVarint32(scratch, target.size());
   scratch->append(target.data(), target.size());
@@ -66,22 +174,62 @@ static const char* EncodeKey(std::string* scratch, const Slice& target) {
 
 class MemTableIterator: public Iterator {
  public:
-  explicit MemTableIterator(MemTableRep* table)
-    : iter_(table->GetIterator()) { }
+  MemTableIterator(const MemTable& mem, const ReadOptions& options,
+                   bool enforce_total_order, Arena* arena)
+      : bloom_(nullptr),
+        prefix_extractor_(mem.prefix_extractor_),
+        valid_(false),
+        arena_mode_(arena != nullptr) {
+    if (prefix_extractor_ != nullptr && !enforce_total_order) {
+      bloom_ = mem.prefix_bloom_.get();
+      iter_ = mem.table_->GetDynamicPrefixIterator(arena);
+    } else {
+      iter_ = mem.table_->GetIterator(arena);
+    }
+  }
 
-  MemTableIterator(MemTableRep* table, const Slice* prefix)
-    : iter_(table->GetPrefixIterator(*prefix)) { }
+  ~MemTableIterator() {
+    if (arena_mode_) {
+      iter_->~Iterator();
+    } else {
+      delete iter_;
+    }
+  }
 
-  virtual bool Valid() const { return iter_->Valid(); }
-  virtual void Seek(const Slice& k) { iter_->Seek(EncodeKey(&tmp_, k)); }
-  virtual void SeekToFirst() { iter_->SeekToFirst(); }
-  virtual void SeekToLast() { iter_->SeekToLast(); }
-  virtual void Next() { iter_->Next(); }
-  virtual void Prev() { iter_->Prev(); }
+  virtual bool Valid() const { return valid_; }
+  virtual void Seek(const Slice& k) {
+    if (bloom_ != nullptr &&
+        !bloom_->MayContain(prefix_extractor_->Transform(ExtractUserKey(k)))) {
+      valid_ = false;
+      return;
+    }
+    iter_->Seek(k, nullptr);
+    valid_ = iter_->Valid();
+  }
+  virtual void SeekToFirst() {
+    iter_->SeekToFirst();
+    valid_ = iter_->Valid();
+  }
+  virtual void SeekToLast() {
+    iter_->SeekToLast();
+    valid_ = iter_->Valid();
+  }
+  virtual void Next() {
+    assert(Valid());
+    iter_->Next();
+    valid_ = iter_->Valid();
+  }
+  virtual void Prev() {
+    assert(Valid());
+    iter_->Prev();
+    valid_ = iter_->Valid();
+  }
   virtual Slice key() const {
+    assert(Valid());
     return GetLengthPrefixedSlice(iter_->key());
   }
   virtual Slice value() const {
+    assert(Valid());
     Slice key_slice = GetLengthPrefixedSlice(iter_->key());
     return GetLengthPrefixedSlice(key_slice.data() + key_slice.size());
   }
@@ -89,24 +237,35 @@ class MemTableIterator: public Iterator {
   virtual Status status() const { return Status::OK(); }
 
  private:
-  std::shared_ptr<MemTableRep::Iterator> iter_;
-  std::string tmp_;       // For passing to EncodeKey
+  DynamicBloom* bloom_;
+  const SliceTransform* const prefix_extractor_;
+  MemTableRep::Iterator* iter_;
+  bool valid_;
+  bool arena_mode_;
 
   // No copying allowed
   MemTableIterator(const MemTableIterator&);
   void operator=(const MemTableIterator&);
 };
 
-Iterator* MemTable::NewIterator(const Slice* prefix) {
-  if (prefix) {
-    return new MemTableIterator(table_.get(), prefix);
+Iterator* MemTable::NewIterator(const ReadOptions& options,
+                                bool enforce_total_order, Arena* arena) {
+  if (arena == nullptr) {
+    return new MemTableIterator(*this, options, enforce_total_order, nullptr);
   } else {
-    return new MemTableIterator(table_.get());
+    auto mem = arena->AllocateAligned(sizeof(MemTableIterator));
+    return new (mem)
+        MemTableIterator(*this, options, enforce_total_order, arena);
   }
 }
 
+port::RWMutex* MemTable::GetLock(const Slice& key) {
+  static murmur_hash hash;
+  return &locks_[hash(key) % locks_.size()];
+}
+
 void MemTable::Add(SequenceNumber s, ValueType type,
-                   const Slice& key,
+                   const Slice& key, /* user key */
                    const Slice& value) {
   // Format of an entry is concatenation of:
   //  key_size     : varint32 of internal_key.size()
@@ -119,7 +278,9 @@ void MemTable::Add(SequenceNumber s, ValueType type,
   const size_t encoded_len =
       VarintLength(internal_key_size) + internal_key_size +
       VarintLength(val_size) + val_size;
-  char* buf = arena_impl_.Allocate(encoded_len);
+  char* buf = nullptr;
+  KeyHandle handle = table_->Allocate(encoded_len, &buf);
+  assert(buf != nullptr);
   char* p = EncodeVarint32(buf, internal_key_size);
   memcpy(p, key.data(), key_size);
   p += key_size;
@@ -127,34 +288,174 @@ void MemTable::Add(SequenceNumber s, ValueType type,
   p += 8;
   p = EncodeVarint32(p, val_size);
   memcpy(p, value.data(), val_size);
-  assert((p + val_size) - buf == (unsigned)encoded_len);
-  table_->Insert(buf);
+  assert((unsigned)(p + val_size - buf) == (unsigned)encoded_len);
+  table_->Insert(handle);
+  num_entries_++;
+
+  if (prefix_bloom_) {
+    assert(prefix_extractor_);
+    prefix_bloom_->Add(prefix_extractor_->Transform(key));
+  }
 
   // The first sequence number inserted into the memtable
   assert(first_seqno_ == 0 || s > first_seqno_);
   if (first_seqno_ == 0) {
     first_seqno_ = s;
   }
+
+  should_flush_ = ShouldFlushNow();
+}
+
+// Callback from MemTable::Get()
+namespace {
+
+struct Saver {
+  Status* status;
+  const LookupKey* key;
+  bool* found_final_value;  // Is value set correctly? Used by KeyMayExist
+  bool* merge_in_progress;
+  std::string* value;
+  const MergeOperator* merge_operator;
+  // the merge operations encountered;
+  MergeContext* merge_context;
+  MemTable* mem;
+  Logger* logger;
+  Statistics* statistics;
+  bool inplace_update_support;
+};
+}  // namespace
+
+static bool SaveValue(void* arg, const char* entry) {
+  Saver* s = reinterpret_cast<Saver*>(arg);
+  MergeContext* merge_context = s->merge_context;
+  const MergeOperator* merge_operator = s->merge_operator;
+
+  assert(s != nullptr && merge_context != nullptr);
+
+  // entry format is:
+  //    klength  varint32
+  //    userkey  char[klength-8]
+  //    tag      uint64
+  //    vlength  varint32
+  //    value    char[vlength]
+  // Check that it belongs to same user key.  We do not check the
+  // sequence number since the Seek() call above should have skipped
+  // all entries with overly large sequence numbers.
+  uint32_t key_length;
+  const char* key_ptr = GetVarint32Ptr(entry, entry + 5, &key_length);
+  if (s->mem->GetInternalKeyComparator().user_comparator()->Compare(
+          Slice(key_ptr, key_length - 8), s->key->user_key()) == 0) {
+    // Correct user key
+    const uint64_t tag = DecodeFixed64(key_ptr + key_length - 8);
+    switch (static_cast<ValueType>(tag & 0xff)) {
+      case kTypeValue: {
+        if (s->inplace_update_support) {
+          s->mem->GetLock(s->key->user_key())->ReadLock();
+        }
+        Slice v = GetLengthPrefixedSlice(key_ptr + key_length);
+        *(s->status) = Status::OK();
+        if (*(s->merge_in_progress)) {
+          assert(merge_operator);
+          if (!merge_operator->FullMerge(s->key->user_key(), &v,
+                                         merge_context->GetOperands(), s->value,
+                                         s->logger)) {
+            RecordTick(s->statistics, NUMBER_MERGE_FAILURES);
+            *(s->status) =
+                Status::Corruption("Error: Could not perform merge.");
+          }
+        } else {
+          s->value->assign(v.data(), v.size());
+        }
+        if (s->inplace_update_support) {
+          s->mem->GetLock(s->key->user_key())->ReadUnlock();
+        }
+        *(s->found_final_value) = true;
+        return false;
+      }
+      case kTypeDeletion: {
+        if (*(s->merge_in_progress)) {
+          assert(merge_operator);
+          *(s->status) = Status::OK();
+          if (!merge_operator->FullMerge(s->key->user_key(), nullptr,
+                                         merge_context->GetOperands(), s->value,
+                                         s->logger)) {
+            RecordTick(s->statistics, NUMBER_MERGE_FAILURES);
+            *(s->status) =
+                Status::Corruption("Error: Could not perform merge.");
+          }
+        } else {
+          *(s->status) = Status::NotFound();
+        }
+        *(s->found_final_value) = true;
+        return false;
+      }
+      case kTypeMerge: {
+        std::string merge_result;  // temporary area for merge results later
+        Slice v = GetLengthPrefixedSlice(key_ptr + key_length);
+        *(s->merge_in_progress) = true;
+        merge_context->PushOperand(v);
+        return true;
+      }
+      default:
+        assert(false);
+        return true;
+    }
+  }
+
+  // s->state could be Corrupt, merge or notfound
+  return false;
 }
 
 bool MemTable::Get(const LookupKey& key, std::string* value, Status* s,
-                   std::deque<std::string>* operands, const Options& options) {
-  Slice memkey = key.memtable_key();
-  std::shared_ptr<MemTableRep::Iterator> iter(
-    table_->GetIterator(key.user_key()));
-  iter->Seek(memkey.data());
-
-  // It is the caller's responsibility to allocate/delete operands list
-  assert(operands != nullptr);
+                   MergeContext& merge_context, const Options& options) {
+  PERF_TIMER_AUTO(get_from_memtable_time);
 
+  Slice user_key = key.user_key();
+  bool found_final_value = false;
   bool merge_in_progress = s->IsMergeInProgress();
-  auto merge_operator = options.merge_operator.get();
-  auto logger = options.info_log;
-  std::string merge_result;
 
-  for (; iter->Valid(); iter->Next()) {
+  if (prefix_bloom_ &&
+      !prefix_bloom_->MayContain(prefix_extractor_->Transform(user_key))) {
+    // iter is null if prefix bloom says the key does not exist
+  } else {
+    Saver saver;
+    saver.status = s;
+    saver.found_final_value = &found_final_value;
+    saver.merge_in_progress = &merge_in_progress;
+    saver.key = &key;
+    saver.value = value;
+    saver.status = s;
+    saver.mem = this;
+    saver.merge_context = &merge_context;
+    saver.merge_operator = options.merge_operator.get();
+    saver.logger = options.info_log.get();
+    saver.inplace_update_support = options.inplace_update_support;
+    saver.statistics = options.statistics.get();
+    table_->Get(key, &saver, SaveValue);
+  }
+
+  // No change to value, since we have not yet found a Put/Delete
+  if (!found_final_value && merge_in_progress) {
+    *s = Status::MergeInProgress("");
+  }
+  PERF_TIMER_STOP(get_from_memtable_time);
+  PERF_COUNTER_ADD(get_from_memtable_count, 1);
+  return found_final_value;
+}
+
+void MemTable::Update(SequenceNumber seq,
+                      const Slice& key,
+                      const Slice& value) {
+  LookupKey lkey(key, seq);
+  Slice mem_key = lkey.memtable_key();
+
+  std::unique_ptr<MemTableRep::Iterator> iter(
+      table_->GetDynamicPrefixIterator());
+  iter->Seek(lkey.internal_key(), mem_key.data());
+
+  if (iter->Valid()) {
     // entry format is:
-    //    klength  varint32
+    //    key_length  varint32
     //    userkey  char[klength-8]
     //    tag      uint64
     //    vlength  varint32
@@ -163,79 +464,158 @@ bool MemTable::Get(const LookupKey& key, std::string* value, Status* s,
     // sequence number since the Seek() call above should have skipped
     // all entries with overly large sequence numbers.
     const char* entry = iter->key();
-    uint32_t key_length;
-    const char* key_ptr = GetVarint32Ptr(entry, entry+5, &key_length);
+    uint32_t key_length = 0;
+    const char* key_ptr = GetVarint32Ptr(entry, entry + 5, &key_length);
     if (comparator_.comparator.user_comparator()->Compare(
-            Slice(key_ptr, key_length - 8),
-            key.user_key()) == 0) {
+        Slice(key_ptr, key_length - 8), lkey.user_key()) == 0) {
       // Correct user key
       const uint64_t tag = DecodeFixed64(key_ptr + key_length - 8);
       switch (static_cast<ValueType>(tag & 0xff)) {
         case kTypeValue: {
-          Slice v = GetLengthPrefixedSlice(key_ptr + key_length);
-          *s = Status::OK();
-          if (merge_in_progress) {
-            assert(merge_operator);
-            if (!merge_operator->FullMerge(key.user_key(), &v, *operands,
-                                           value, logger.get())) {
-              RecordTick(options.statistics, NUMBER_MERGE_FAILURES);
-              *s = Status::Corruption("Error: Could not perform merge.");
-            }
-          } else {
-            value->assign(v.data(), v.size());
+          Slice prev_value = GetLengthPrefixedSlice(key_ptr + key_length);
+          uint32_t prev_size = prev_value.size();
+          uint32_t new_size = value.size();
+
+          // Update value, if new value size  <= previous value size
+          if (new_size <= prev_size ) {
+            char* p = EncodeVarint32(const_cast<char*>(key_ptr) + key_length,
+                                     new_size);
+            WriteLock wl(GetLock(lkey.user_key()));
+            memcpy(p, value.data(), value.size());
+            assert((unsigned)((p + value.size()) - entry) ==
+                   (unsigned)(VarintLength(key_length) + key_length +
+                              VarintLength(value.size()) + value.size()));
+            return;
           }
-          return true;
         }
-        case kTypeDeletion: {
-          if (merge_in_progress) {
-            assert(merge_operator);
-            *s = Status::OK();
-            if (!merge_operator->FullMerge(key.user_key(), nullptr, *operands,
-                                           value, logger.get())) {
-              RecordTick(options.statistics, NUMBER_MERGE_FAILURES);
-              *s = Status::Corruption("Error: Could not perform merge.");
-            }
-          } else {
-            *s = Status::NotFound(Slice());
-          }
-          return true;
-        }
-        case kTypeMerge: {
-          Slice v = GetLengthPrefixedSlice(key_ptr + key_length);
-          merge_in_progress = true;
-          operands->push_front(v.ToString());
-          while(operands->size() >= 2) {
-            // Attempt to associative merge. (Returns true if successful)
-            if (merge_operator->PartialMerge(key.user_key(),
-                                             Slice((*operands)[0]),
-                                             Slice((*operands)[1]),
-                                             &merge_result,
-                                             logger.get())) {
-              operands->pop_front();
-              swap(operands->front(), merge_result);
-            } else {
-              // Stack them because user can't associative merge
-              break;
-            }
-          }
-          break;
-        }
-        case kTypeLogData:
-          assert(false);
-          break;
+        default:
+          // If the latest value is kTypeDeletion, kTypeMerge or kTypeLogData
+          // we don't have enough space for update inplace
+            Add(seq, kTypeValue, key, value);
+            return;
       }
-    } else {
-      // exit loop if user key does not match
-      break;
     }
   }
 
-  // No change to value, since we have not yet found a Put/Delete
+  // key doesn't exist
+  Add(seq, kTypeValue, key, value);
+}
 
-  if (merge_in_progress) {
-    *s = Status::MergeInProgress("");
+bool MemTable::UpdateCallback(SequenceNumber seq,
+                              const Slice& key,
+                              const Slice& delta,
+                              const Options& options) {
+  LookupKey lkey(key, seq);
+  Slice memkey = lkey.memtable_key();
+
+  std::unique_ptr<MemTableRep::Iterator> iter(
+      table_->GetDynamicPrefixIterator());
+  iter->Seek(lkey.internal_key(), memkey.data());
+
+  if (iter->Valid()) {
+    // entry format is:
+    //    key_length  varint32
+    //    userkey  char[klength-8]
+    //    tag      uint64
+    //    vlength  varint32
+    //    value    char[vlength]
+    // Check that it belongs to same user key.  We do not check the
+    // sequence number since the Seek() call above should have skipped
+    // all entries with overly large sequence numbers.
+    const char* entry = iter->key();
+    uint32_t key_length = 0;
+    const char* key_ptr = GetVarint32Ptr(entry, entry + 5, &key_length);
+    if (comparator_.comparator.user_comparator()->Compare(
+        Slice(key_ptr, key_length - 8), lkey.user_key()) == 0) {
+      // Correct user key
+      const uint64_t tag = DecodeFixed64(key_ptr + key_length - 8);
+      switch (static_cast<ValueType>(tag & 0xff)) {
+        case kTypeValue: {
+          Slice prev_value = GetLengthPrefixedSlice(key_ptr + key_length);
+          uint32_t  prev_size = prev_value.size();
+
+          char* prev_buffer = const_cast<char*>(prev_value.data());
+          uint32_t  new_prev_size = prev_size;
+
+          std::string str_value;
+          WriteLock wl(GetLock(lkey.user_key()));
+          auto status = options.inplace_callback(prev_buffer, &new_prev_size,
+                                                    delta, &str_value);
+          if (status == UpdateStatus::UPDATED_INPLACE) {
+            // Value already updated by callback.
+            assert(new_prev_size <= prev_size);
+            if (new_prev_size < prev_size) {
+              // overwrite the new prev_size
+              char* p = EncodeVarint32(const_cast<char*>(key_ptr) + key_length,
+                                       new_prev_size);
+              if (VarintLength(new_prev_size) < VarintLength(prev_size)) {
+                // shift the value buffer as well.
+                memcpy(p, prev_buffer, new_prev_size);
+              }
+            }
+            RecordTick(options.statistics.get(), NUMBER_KEYS_UPDATED);
+            should_flush_ = ShouldFlushNow();
+            return true;
+          } else if (status == UpdateStatus::UPDATED) {
+            Add(seq, kTypeValue, key, Slice(str_value));
+            RecordTick(options.statistics.get(), NUMBER_KEYS_WRITTEN);
+            should_flush_ = ShouldFlushNow();
+            return true;
+          } else if (status == UpdateStatus::UPDATE_FAILED) {
+            // No action required. Return.
+            should_flush_ = ShouldFlushNow();
+            return true;
+          }
+        }
+        default:
+          break;
+      }
+    }
   }
+  // If the latest value is not kTypeValue
+  // or key doesn't exist
   return false;
 }
 
+size_t MemTable::CountSuccessiveMergeEntries(const LookupKey& key) {
+  Slice memkey = key.memtable_key();
+
+  // A total ordered iterator is costly for some memtablerep (prefix aware
+  // reps). By passing in the user key, we allow efficient iterator creation.
+  // The iterator only needs to be ordered within the same user key.
+  std::unique_ptr<MemTableRep::Iterator> iter(
+      table_->GetDynamicPrefixIterator());
+  iter->Seek(key.internal_key(), memkey.data());
+
+  size_t num_successive_merges = 0;
+
+  for (; iter->Valid(); iter->Next()) {
+    const char* entry = iter->key();
+    uint32_t key_length = 0;
+    const char* iter_key_ptr = GetVarint32Ptr(entry, entry + 5, &key_length);
+    if (comparator_.comparator.user_comparator()->Compare(
+            Slice(iter_key_ptr, key_length - 8), key.user_key()) != 0) {
+      break;
+    }
+
+    const uint64_t tag = DecodeFixed64(iter_key_ptr + key_length - 8);
+    if (static_cast<ValueType>(tag & 0xff) != kTypeMerge) {
+      break;
+    }
+
+    ++num_successive_merges;
+  }
+
+  return num_successive_merges;
+}
+
+void MemTableRep::Get(const LookupKey& k, void* callback_args,
+                      bool (*callback_func)(void* arg, const char* entry)) {
+  auto iter = GetDynamicPrefixIterator();
+  for (iter->Seek(k.internal_key(), k.memtable_key().data());
+       iter->Valid() && callback_func(callback_args, iter->key());
+       iter->Next()) {
+  }
+}
+
 }  // namespace rocksdb

db/memtable.h

@@ -1,51 +1,61 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
-#ifndef STORAGE_LEVELDB_DB_MEMTABLE_H_
-#define STORAGE_LEVELDB_DB_MEMTABLE_H_
-
+#pragma once
 #include <string>
 #include <memory>
 #include <deque>
 #include "db/dbformat.h"
 #include "db/skiplist.h"
-#include "db/version_set.h"
+#include "db/version_edit.h"
 #include "rocksdb/db.h"
 #include "rocksdb/memtablerep.h"
-#include "util/arena_impl.h"
+#include "util/arena.h"
+#include "util/dynamic_bloom.h"
 
 namespace rocksdb {
 
+class Arena;
 class Mutex;
 class MemTableIterator;
+class MergeContext;
 
 class MemTable {
  public:
   struct KeyComparator : public MemTableRep::KeyComparator {
     const InternalKeyComparator comparator;
     explicit KeyComparator(const InternalKeyComparator& c) : comparator(c) { }
-    virtual int operator()(const char* a, const char* b) const;
+    virtual int operator()(const char* prefix_len_key1,
+                           const char* prefix_len_key2) const;
+    virtual int operator()(const char* prefix_len_key,
+                           const Slice& key) const override;
   };
 
   // MemTables are reference counted.  The initial reference count
   // is zero and the caller must call Ref() at least once.
-  explicit MemTable(
-    const InternalKeyComparator& comparator,
-    std::shared_ptr<MemTableRepFactory> table_factory,
-    int numlevel = 7,
-    const Options& options = Options());
+  explicit MemTable(const InternalKeyComparator& comparator,
+                    const Options& options);
+
+  ~MemTable();
 
   // Increase reference count.
   void Ref() { ++refs_; }
 
-  // Drop reference count.  Delete if no more references exist.
-  void Unref() {
+  // Drop reference count.
+  // If the refcount goes to zero return this memtable, otherwise return null
+  MemTable* Unref() {
     --refs_;
     assert(refs_ >= 0);
     if (refs_ <= 0) {
-      delete this;
+      return this;
     }
+    return nullptr;
   }
 
   // Returns an estimate of the number of bytes of data in use by this
@@ -55,6 +65,10 @@ class MemTable {
   // operations on the same MemTable.
   size_t ApproximateMemoryUsage();
 
+  // This method heuristically determines if the memtable should continue to
+  // host more data.
+  bool ShouldFlush() const { return should_flush_; }
+
   // Return an iterator that yields the contents of the memtable.
   //
   // The caller must ensure that the underlying MemTable remains live
@@ -62,10 +76,14 @@ class MemTable {
   // iterator are internal keys encoded by AppendInternalKey in the
   // db/dbformat.{h,cc} module.
   //
-  // If a prefix is supplied, it is passed to the underlying MemTableRep as a
-  // hint that the iterator only need to support access to keys with that
-  // prefix.
-  Iterator* NewIterator(const Slice* prefix = nullptr);
+  // By default, it returns an iterator for prefix seek if prefix_extractor
+  // is configured in Options.
+  // arena: If not null, the arena needs to be used to allocate the Iterator.
+  //        Calling ~Iterator of the iterator will destroy all the states but
+  //        those allocated in arena.
+  Iterator* NewIterator(const ReadOptions& options,
+                        bool enforce_total_order = false,
+                        Arena* arena = nullptr);
 
   // Add an entry into memtable that maps key to value at the
   // specified sequence number and with the specified type.
@@ -83,7 +101,40 @@ class MemTable {
   //   store MergeInProgress in s, and return false.
   // Else, return false.
   bool Get(const LookupKey& key, std::string* value, Status* s,
-           std::deque<std::string>* operands, const Options& options);
+           MergeContext& merge_context, const Options& options);
+
+  // Attempts to update the new_value inplace, else does normal Add
+  // Pseudocode
+  //   if key exists in current memtable && prev_value is of type kTypeValue
+  //     if new sizeof(new_value) <= sizeof(prev_value)
+  //       update inplace
+  //     else add(key, new_value)
+  //   else add(key, new_value)
+  void Update(SequenceNumber seq,
+              const Slice& key,
+              const Slice& value);
+
+  // If prev_value for key exits, attempts to update it inplace.
+  // else returns false
+  // Pseudocode
+  //   if key exists in current memtable && prev_value is of type kTypeValue
+  //     new_value = delta(prev_value)
+  //     if sizeof(new_value) <= sizeof(prev_value)
+  //       update inplace
+  //     else add(key, new_value)
+  //   else return false
+  bool UpdateCallback(SequenceNumber seq,
+                      const Slice& key,
+                      const Slice& delta,
+                      const Options& options);
+
+  // Returns the number of successive merge entries starting from the newest
+  // entry for the key up to the last non-merge entry or last entry for the
+  // key in the memtable.
+  size_t CountSuccessiveMergeEntries(const LookupKey& key);
+
+  // Get total number of entries in the mem table.
+  uint64_t GetNumEntries() const { return num_entries_; }
 
   // Returns the edits area that is needed for flushing the memtable
   VersionEdit* GetEdits() { return &edit_; }
@@ -100,34 +151,49 @@ class MemTable {
   // be flushed to storage
   void SetNextLogNumber(uint64_t num) { mem_next_logfile_number_ = num; }
 
-  // Returns the logfile number that can be safely deleted when this
-  // memstore is flushed to storage
-  uint64_t GetLogNumber() { return mem_logfile_number_; }
-
-  // Sets the logfile number that can be safely deleted when this
-  // memstore is flushed to storage
-  void SetLogNumber(uint64_t num) { mem_logfile_number_ = num; }
-
   // Notify the underlying storage that no more items will be added
   void MarkImmutable() { table_->MarkReadOnly(); }
 
+  // return true if the current MemTableRep supports merge operator.
+  bool IsMergeOperatorSupported() const {
+    return table_->IsMergeOperatorSupported();
+  }
+
+  // return true if the current MemTableRep supports snapshots.
+  bool IsSnapshotSupported() const { return table_->IsSnapshotSupported(); }
+
+  // Get the lock associated for the key
+  port::RWMutex* GetLock(const Slice& key);
+
+  const InternalKeyComparator& GetInternalKeyComparator() const {
+    return comparator_.comparator;
+  }
+
+  const Arena& TEST_GetArena() const { return arena_; }
+
  private:
-  ~MemTable();  // Private since only Unref() should be used to delete it
+  // Dynamically check if we can add more incoming entries.
+  bool ShouldFlushNow() const;
+
   friend class MemTableIterator;
   friend class MemTableBackwardIterator;
   friend class MemTableList;
 
   KeyComparator comparator_;
   int refs_;
-  ArenaImpl arena_impl_;
-  shared_ptr<MemTableRep> table_;
+  const size_t kArenaBlockSize;
+  const size_t kWriteBufferSize;
+  Arena arena_;
+  unique_ptr<MemTableRep> table_;
+
+  uint64_t num_entries_;
 
   // These are used to manage memtable flushes to storage
   bool flush_in_progress_; // started the flush
   bool flush_completed_;   // finished the flush
   uint64_t file_number_;    // filled up after flush is complete
 
-  // The udpates to be applied to the transaction log when this
+  // The updates to be applied to the transaction log when this
   // memtable is flushed to storage.
   VersionEdit edit_;
 
@@ -137,15 +203,20 @@ class MemTable {
   // The log files earlier than this number can be deleted.
   uint64_t mem_next_logfile_number_;
 
-  // The log file that backs this memtable (to be deleted when
-  // memtable flush is done)
-  uint64_t mem_logfile_number_;
+  // rw locks for inplace updates
+  std::vector<port::RWMutex> locks_;
 
   // No copying allowed
   MemTable(const MemTable&);
   void operator=(const MemTable&);
+
+  const SliceTransform* const prefix_extractor_;
+  std::unique_ptr<DynamicBloom> prefix_bloom_;
+
+  // a flag indicating if a memtable has met the criteria to flush
+  bool should_flush_;
 };
 
-}  // namespace rocksdb
+extern const char* EncodeKey(std::string* scratch, const Slice& target);
 
-#endif  // STORAGE_LEVELDB_DB_MEMTABLE_H_
+}  // namespace rocksdb

db/memtable_list.cc

@@ -0,0 +1,286 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+#include "db/memtable_list.h"
+
+#include <string>
+#include "rocksdb/db.h"
+#include "db/memtable.h"
+#include "db/version_set.h"
+#include "rocksdb/env.h"
+#include "rocksdb/iterator.h"
+#include "table/merger.h"
+#include "util/coding.h"
+#include "util/log_buffer.h"
+
+namespace rocksdb {
+
+class InternalKeyComparator;
+class Mutex;
+class VersionSet;
+
+MemTableListVersion::MemTableListVersion(MemTableListVersion* old) {
+  if (old != nullptr) {
+    memlist_ = old->memlist_;
+    size_ = old->size_;
+    for (auto& m : memlist_) {
+      m->Ref();
+    }
+  }
+}
+
+void MemTableListVersion::Ref() { ++refs_; }
+
+void MemTableListVersion::Unref(autovector<MemTable*>* to_delete) {
+  assert(refs_ >= 1);
+  --refs_;
+  if (refs_ == 0) {
+    // if to_delete is equal to nullptr it means we're confident
+    // that refs_ will not be zero
+    assert(to_delete != nullptr);
+    for (const auto& m : memlist_) {
+      MemTable* x = m->Unref();
+      if (x != nullptr) {
+        to_delete->push_back(x);
+      }
+    }
+    delete this;
+  }
+}
+
+int MemTableListVersion::size() const { return size_; }
+
+// Returns the total number of memtables in the list
+int MemTableList::size() const {
+  assert(num_flush_not_started_ <= current_->size_);
+  return current_->size_;
+}
+
+// Search all the memtables starting from the most recent one.
+// Return the most recent value found, if any.
+// Operands stores the list of merge operations to apply, so far.
+bool MemTableListVersion::Get(const LookupKey& key, std::string* value,
+                              Status* s, MergeContext& merge_context,
+                              const Options& options) {
+  for (auto& memtable : memlist_) {
+    if (memtable->Get(key, value, s, merge_context, options)) {
+      return true;
+    }
+  }
+  return false;
+}
+
+void MemTableListVersion::AddIterators(const ReadOptions& options,
+                                       std::vector<Iterator*>* iterator_list) {
+  for (auto& m : memlist_) {
+    iterator_list->push_back(m->NewIterator(options));
+  }
+}
+
+void MemTableListVersion::AddIterators(
+    const ReadOptions& options, MergeIteratorBuilder* merge_iter_builder) {
+  for (auto& m : memlist_) {
+    merge_iter_builder->AddIterator(
+        m->NewIterator(options, merge_iter_builder->GetArena()));
+  }
+}
+
+uint64_t MemTableListVersion::GetTotalNumEntries() const {
+  uint64_t total_num = 0;
+  for (auto& m : memlist_) {
+    total_num += m->GetNumEntries();
+  }
+  return total_num;
+}
+
+// caller is responsible for referencing m
+void MemTableListVersion::Add(MemTable* m) {
+  assert(refs_ == 1);  // only when refs_ == 1 is MemTableListVersion mutable
+  memlist_.push_front(m);
+  ++size_;
+}
+
+// caller is responsible for unreferencing m
+void MemTableListVersion::Remove(MemTable* m) {
+  assert(refs_ == 1);  // only when refs_ == 1 is MemTableListVersion mutable
+  memlist_.remove(m);
+  --size_;
+}
+
+// Returns true if there is at least one memtable on which flush has
+// not yet started.
+bool MemTableList::IsFlushPending() const {
+  if ((flush_requested_ && num_flush_not_started_ >= 1) ||
+      (num_flush_not_started_ >= min_write_buffer_number_to_merge_)) {
+    assert(imm_flush_needed.NoBarrier_Load() != nullptr);
+    return true;
+  }
+  return false;
+}
+
+// Returns the memtables that need to be flushed.
+void MemTableList::PickMemtablesToFlush(autovector<MemTable*>* ret) {
+  const auto& memlist = current_->memlist_;
+  for (auto it = memlist.rbegin(); it != memlist.rend(); ++it) {
+    MemTable* m = *it;
+    if (!m->flush_in_progress_) {
+      assert(!m->flush_completed_);
+      num_flush_not_started_--;
+      if (num_flush_not_started_ == 0) {
+        imm_flush_needed.Release_Store(nullptr);
+      }
+      m->flush_in_progress_ = true;  // flushing will start very soon
+      ret->push_back(m);
+    }
+  }
+  flush_requested_ = false;  // start-flush request is complete
+}
+
+void MemTableList::RollbackMemtableFlush(const autovector<MemTable*>& mems,
+                                         uint64_t file_number,
+                                         FileNumToPathIdMap* pending_outputs) {
+  assert(!mems.empty());
+
+  // If the flush was not successful, then just reset state.
+  // Maybe a suceeding attempt to flush will be successful.
+  for (MemTable* m : mems) {
+    assert(m->flush_in_progress_);
+    assert(m->file_number_ == 0);
+
+    m->flush_in_progress_ = false;
+    m->flush_completed_ = false;
+    m->edit_.Clear();
+    num_flush_not_started_++;
+  }
+  pending_outputs->erase(file_number);
+  imm_flush_needed.Release_Store(reinterpret_cast<void *>(1));
+}
+
+// Record a successful flush in the manifest file
+Status MemTableList::InstallMemtableFlushResults(
+    ColumnFamilyData* cfd, const autovector<MemTable*>& mems, VersionSet* vset,
+    port::Mutex* mu, Logger* info_log, uint64_t file_number,
+    FileNumToPathIdMap* pending_outputs, autovector<MemTable*>* to_delete,
+    Directory* db_directory, LogBuffer* log_buffer) {
+  mu->AssertHeld();
+
+  // flush was sucessful
+  for (size_t i = 0; i < mems.size(); ++i) {
+    // All the edits are associated with the first memtable of this batch.
+    assert(i == 0 || mems[i]->GetEdits()->NumEntries() == 0);
+
+    mems[i]->flush_completed_ = true;
+    mems[i]->file_number_ = file_number;
+  }
+
+  // if some other thread is already commiting, then return
+  Status s;
+  if (commit_in_progress_) {
+    return s;
+  }
+
+  // Only a single thread can be executing this piece of code
+  commit_in_progress_ = true;
+
+  // scan all memtables from the earliest, and commit those
+  // (in that order) that have finished flushing. Memetables
+  // are always committed in the order that they were created.
+  while (!current_->memlist_.empty() && s.ok()) {
+    MemTable* m = current_->memlist_.back();  // get the last element
+    if (!m->flush_completed_) {
+      break;
+    }
+
+    LogToBuffer(log_buffer, "[%s] Level-0 commit table #%lu started",
+                cfd->GetName().c_str(), (unsigned long)m->file_number_);
+
+    // this can release and reacquire the mutex.
+    s = vset->LogAndApply(cfd, &m->edit_, mu, db_directory);
+
+    // we will be changing the version in the next code path,
+    // so we better create a new one, since versions are immutable
+    InstallNewVersion();
+
+    // All the later memtables that have the same filenum
+    // are part of the same batch. They can be committed now.
+    uint64_t mem_id = 1;  // how many memtables has been flushed.
+    do {
+      if (s.ok()) { // commit new state
+        LogToBuffer(log_buffer,
+                    "[%s] Level-0 commit table #%lu: memtable #%lu done",
+                    cfd->GetName().c_str(), (unsigned long)m->file_number_,
+                    (unsigned long)mem_id);
+        current_->Remove(m);
+        assert(m->file_number_ > 0);
+
+        // pending_outputs can be cleared only after the newly created file
+        // has been written to a committed version so that other concurrently
+        // executing compaction threads do not mistakenly assume that this
+        // file is not live.
+        pending_outputs->erase(m->file_number_);
+        if (m->Unref() != nullptr) {
+          to_delete->push_back(m);
+        }
+      } else {
+        //commit failed. setup state so that we can flush again.
+        Log(info_log,
+            "Level-0 commit table #%lu: memtable #%lu failed",
+            (unsigned long)m->file_number_,
+            (unsigned long)mem_id);
+        m->flush_completed_ = false;
+        m->flush_in_progress_ = false;
+        m->edit_.Clear();
+        num_flush_not_started_++;
+        pending_outputs->erase(m->file_number_);
+        m->file_number_ = 0;
+        imm_flush_needed.Release_Store((void *)1);
+      }
+      ++mem_id;
+    } while (!current_->memlist_.empty() && (m = current_->memlist_.back()) &&
+             m->file_number_ == file_number);
+  }
+  commit_in_progress_ = false;
+  return s;
+}
+
+// New memtables are inserted at the front of the list.
+void MemTableList::Add(MemTable* m) {
+  assert(current_->size_ >= num_flush_not_started_);
+  InstallNewVersion();
+  // this method is used to move mutable memtable into an immutable list.
+  // since mutable memtable is already refcounted by the DBImpl,
+  // and when moving to the imutable list we don't unref it,
+  // we don't have to ref the memtable here. we just take over the
+  // reference from the DBImpl.
+  current_->Add(m);
+  m->MarkImmutable();
+  num_flush_not_started_++;
+  if (num_flush_not_started_ == 1) {
+    imm_flush_needed.Release_Store((void *)1);
+  }
+}
+
+// Returns an estimate of the number of bytes of data in use.
+size_t MemTableList::ApproximateMemoryUsage() {
+  size_t size = 0;
+  for (auto& memtable : current_->memlist_) {
+    size += memtable->ApproximateMemoryUsage();
+  }
+  return size;
+}
+
+void MemTableList::InstallNewVersion() {
+  if (current_->refs_ == 1) {
+    // we're the only one using the version, just keep using it
+  } else {
+    // somebody else holds the current version, we need to create new one
+    MemTableListVersion* version = current_;
+    current_ = new MemTableListVersion(current_);
+    current_->Ref();
+    version->Unref();
+  }
+}
+
+}  // namespace rocksdb

db/memtable_list.h

@@ -0,0 +1,154 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+#pragma once
+
+#include <string>
+#include <list>
+#include <vector>
+#include <set>
+#include <deque>
+#include "rocksdb/db.h"
+#include "rocksdb/options.h"
+#include "rocksdb/iterator.h"
+
+#include "db/dbformat.h"
+#include "db/filename.h"
+#include "db/skiplist.h"
+#include "db/memtable.h"
+#include "rocksdb/db.h"
+#include "rocksdb/iterator.h"
+#include "rocksdb/options.h"
+#include "util/autovector.h"
+#include "util/log_buffer.h"
+
+namespace rocksdb {
+
+class ColumnFamilyData;
+class InternalKeyComparator;
+class Mutex;
+class MergeIteratorBuilder;
+
+// keeps a list of immutable memtables in a vector. the list is immutable
+// if refcount is bigger than one. It is used as a state for Get() and
+// Iterator code paths
+class MemTableListVersion {
+ public:
+  explicit MemTableListVersion(MemTableListVersion* old = nullptr);
+
+  void Ref();
+  void Unref(autovector<MemTable*>* to_delete = nullptr);
+
+  int size() const;
+
+  // Search all the memtables starting from the most recent one.
+  // Return the most recent value found, if any.
+  bool Get(const LookupKey& key, std::string* value, Status* s,
+           MergeContext& merge_context, const Options& options);
+
+  void AddIterators(const ReadOptions& options,
+                    std::vector<Iterator*>* iterator_list);
+
+  void AddIterators(const ReadOptions& options,
+                    MergeIteratorBuilder* merge_iter_builder);
+
+  uint64_t GetTotalNumEntries() const;
+
+ private:
+  // REQUIRE: m is mutable memtable
+  void Add(MemTable* m);
+  // REQUIRE: m is mutable memtable
+  void Remove(MemTable* m);
+
+  friend class MemTableList;
+  std::list<MemTable*> memlist_;
+  int size_ = 0;
+  int refs_ = 0;
+};
+
+// This class stores references to all the immutable memtables.
+// The memtables are flushed to L0 as soon as possible and in
+// any order. If there are more than one immutable memtable, their
+// flushes can occur concurrently.  However, they are 'committed'
+// to the manifest in FIFO order to maintain correctness and
+// recoverability from a crash.
+class MemTableList {
+ public:
+  // A list of memtables.
+  explicit MemTableList(int min_write_buffer_number_to_merge)
+      : min_write_buffer_number_to_merge_(min_write_buffer_number_to_merge),
+        current_(new MemTableListVersion()),
+        num_flush_not_started_(0),
+        commit_in_progress_(false),
+        flush_requested_(false) {
+    imm_flush_needed.Release_Store(nullptr);
+    current_->Ref();
+  }
+  ~MemTableList() {}
+
+  MemTableListVersion* current() { return current_; }
+
+  // so that background threads can detect non-nullptr pointer to
+  // determine whether there is anything more to start flushing.
+  port::AtomicPointer imm_flush_needed;
+
+  // Returns the total number of memtables in the list
+  int size() const;
+
+  // Returns true if there is at least one memtable on which flush has
+  // not yet started.
+  bool IsFlushPending() const;
+
+  // Returns the earliest memtables that needs to be flushed. The returned
+  // memtables are guaranteed to be in the ascending order of created time.
+  void PickMemtablesToFlush(autovector<MemTable*>* mems);
+
+  // Reset status of the given memtable list back to pending state so that
+  // they can get picked up again on the next round of flush.
+  void RollbackMemtableFlush(const autovector<MemTable*>& mems,
+                             uint64_t file_number,
+                             FileNumToPathIdMap* pending_outputs);
+
+  // Commit a successful flush in the manifest file
+  Status InstallMemtableFlushResults(
+      ColumnFamilyData* cfd, const autovector<MemTable*>& m, VersionSet* vset,
+      port::Mutex* mu, Logger* info_log, uint64_t file_number,
+      FileNumToPathIdMap* pending_outputs, autovector<MemTable*>* to_delete,
+      Directory* db_directory, LogBuffer* log_buffer);
+
+  // New memtables are inserted at the front of the list.
+  // Takes ownership of the referenced held on *m by the caller of Add().
+  void Add(MemTable* m);
+
+  // Returns an estimate of the number of bytes of data in use.
+  size_t ApproximateMemoryUsage();
+
+  // Request a flush of all existing memtables to storage
+  void FlushRequested() { flush_requested_ = true; }
+
+  // Copying allowed
+  // MemTableList(const MemTableList&);
+  // void operator=(const MemTableList&);
+
+ private:
+  // DB mutex held
+  void InstallNewVersion();
+
+  int min_write_buffer_number_to_merge_;
+
+  MemTableListVersion* current_;
+
+  // the number of elements that still need flushing
+  int num_flush_not_started_;
+
+  // committing in progress
+  bool commit_in_progress_;
+
+  // Requested a flush of all memtables to storage
+  bool flush_requested_;
+
+};
+
+}  // namespace rocksdb

db/memtablelist.cc

@@ -1,213 +0,0 @@
-// Copyright (c) 2012 Facebook.
-
-
-#include "db/memtablelist.h"
-
-#include <string>
-#include "rocksdb/db.h"
-#include "db/memtable.h"
-#include "rocksdb/env.h"
-#include "rocksdb/iterator.h"
-#include "util/coding.h"
-
-namespace rocksdb {
-
-class InternalKeyComparator;
-class Mutex;
-class MemTableListIterator;
-class VersionSet;
-
-using std::list;
-
-// Increase reference count on all underling memtables
-void MemTableList::RefAll() {
-  for (auto &memtable : memlist_) {
-    memtable->Ref();
-  }
-}
-
-// Drop reference count on all underling memtables
-void MemTableList::UnrefAll() {
-  for (auto &memtable : memlist_) {
-    memtable->Unref();
-  }
-}
-
-// Returns the total number of memtables in the list
-int MemTableList::size() {
-  assert(num_flush_not_started_ <= size_);
-  return size_;
-}
-
-// Returns true if there is at least one memtable on which flush has
-// not yet started.
-bool MemTableList::IsFlushPending(int min_write_buffer_number_to_merge) {
-  if ((flush_requested_ && num_flush_not_started_ >= 1) ||
-      (num_flush_not_started_ >= min_write_buffer_number_to_merge)) {
-    assert(imm_flush_needed.NoBarrier_Load() != nullptr);
-    return true;
-  }
-  return false;
-}
-
-// Returns the memtables that need to be flushed.
-void MemTableList::PickMemtablesToFlush(std::vector<MemTable*>* ret) {
-  for (auto it = memlist_.rbegin(); it != memlist_.rend(); it++) {
-    MemTable* m = *it;
-    if (!m->flush_in_progress_) {
-      assert(!m->flush_completed_);
-      num_flush_not_started_--;
-      if (num_flush_not_started_ == 0) {
-        imm_flush_needed.Release_Store(nullptr);
-      }
-      m->flush_in_progress_ = true; // flushing will start very soon
-      ret->push_back(m);
-    }
-  }
-  flush_requested_ = false; // start-flush request is complete
-}
-
-// Record a successful flush in the manifest file
-Status MemTableList::InstallMemtableFlushResults(
-                      const std::vector<MemTable*> &mems,
-                      VersionSet* vset, Status flushStatus,
-                      port::Mutex* mu, Logger* info_log,
-                      uint64_t file_number,
-                      std::set<uint64_t>& pending_outputs) {
-  mu->AssertHeld();
-
-  // If the flush was not successful, then just reset state.
-  // Maybe a suceeding attempt to flush will be successful.
-  if (!flushStatus.ok()) {
-    for (MemTable* m : mems) {
-      assert(m->flush_in_progress_);
-      assert(m->file_number_ == 0);
-
-      m->flush_in_progress_ = false;
-      m->flush_completed_ = false;
-      m->edit_.Clear();
-      num_flush_not_started_++;
-      imm_flush_needed.Release_Store((void *)1);
-      pending_outputs.erase(file_number);
-    }
-    return flushStatus;
-  }
-
-  // flush was sucessful
-  bool first = true;
-  for (MemTable* m : mems) {
-
-    // All the edits are associated with the first memtable of this batch.
-    assert(first || m->GetEdits()->NumEntries() == 0);
-    first = false;
-
-    m->flush_completed_ = true;
-    m->file_number_ = file_number;
-  }
-
-  // if some other thread is already commiting, then return
-  Status s;
-  if (commit_in_progress_) {
-    return s;
-  }
-
-  // Only a single thread can be executing this piece of code
-  commit_in_progress_ = true;
-
-  // scan all memtables from the earliest, and commit those
-  // (in that order) that have finished flushing. Memetables
-  // are always committed in the order that they were created.
-  while (!memlist_.empty() && s.ok()) {
-    MemTable* m = memlist_.back(); // get the last element
-    if (!m->flush_completed_) {
-      break;
-    }
-    first = true;
-
-    Log(info_log,
-        "Level-0 commit table #%llu: started",
-        (unsigned long long)m->file_number_);
-
-    // this can release and reacquire the mutex.
-    s = vset->LogAndApply(&m->edit_, mu);
-
-    // All the later memtables that have the same filenum
-    // are part of the same batch. They can be committed now.
-    do {
-      if (s.ok()) { // commit new state
-        Log(info_log, "Level-0 commit table #%llu: done %s",
-                       (unsigned long long)m->file_number_,
-                       first ? "": "bulk");
-        memlist_.remove(m);
-        assert(m->file_number_ > 0);
-
-        // pending_outputs can be cleared only after the newly created file
-        // has been written to a committed version so that other concurrently
-        // executing compaction threads do not mistakenly assume that this
-        // file is not live.
-        pending_outputs.erase(m->file_number_);
-        m->Unref();
-        size_--;
-      } else {
-        //commit failed. setup state so that we can flush again.
-        Log(info_log, "Level-0 commit table #%llu: failed",
-                       (unsigned long long)m->file_number_);
-        m->flush_completed_ = false;
-        m->flush_in_progress_ = false;
-        m->edit_.Clear();
-        num_flush_not_started_++;
-        pending_outputs.erase(m->file_number_);
-        m->file_number_ = 0;
-        imm_flush_needed.Release_Store((void *)1);
-        s = Status::IOError("Unable to commit flushed memtable");
-      }
-      first = false;
-    } while (!memlist_.empty() && (m = memlist_.back()) &&
-             m->file_number_ == file_number);
-  }
-  commit_in_progress_ = false;
-  return s;
-}
-
-// New memtables are inserted at the front of the list.
-void MemTableList::Add(MemTable* m) {
-  assert(size_ >= num_flush_not_started_);
-  size_++;
-  memlist_.push_front(m);
-  m->MarkImmutable();
-  num_flush_not_started_++;
-  if (num_flush_not_started_ == 1) {
-    imm_flush_needed.Release_Store((void *)1);
-  }
-}
-
-// Returns an estimate of the number of bytes of data in use.
-size_t MemTableList::ApproximateMemoryUsage() {
-  size_t size = 0;
-  for (auto &memtable : memlist_) {
-    size += memtable->ApproximateMemoryUsage();
-  }
-  return size;
-}
-
-// Search all the memtables starting from the most recent one.
-// Return the most recent value found, if any.
-// Operands stores the list of merge operations to apply, so far.
-bool MemTableList::Get(const LookupKey& key, std::string* value, Status* s,
-                       std::deque<std::string>* operands,
-                       const Options& options) {
-  for (auto &memtable : memlist_) {
-    if (memtable->Get(key, value, s, operands, options)) {
-      return true;
-    }
-  }
-  return false;
-}
-
-void MemTableList::GetMemTables(std::vector<MemTable*>* output) {
-  for (auto &memtable : memlist_) {
-    output->push_back(memtable);
-  }
-}
-
-}  // namespace rocksdb

db/memtablelist.h

@@ -1,104 +0,0 @@
-// Copyright (c) 2012 Facebook.
-
-#ifndef STORAGE_LEVELDB_DB_MEMTABLELIST_H_
-#define STORAGE_LEVELDB_DB_MEMTABLELIST_H_
-
-#include <string>
-#include <list>
-#include <deque>
-#include "rocksdb/db.h"
-#include "db/dbformat.h"
-#include "db/skiplist.h"
-#include "memtable.h"
-
-namespace rocksdb {
-
-class InternalKeyComparator;
-class Mutex;
-class MemTableListIterator;
-
-//
-// This class stores references to all the immutable memtables.
-// The memtables are flushed to L0 as soon as possible and in
-// any order. If there are more than one immutable memtable, their
-// flushes can occur concurrently.  However, they are 'committed'
-// to the manifest in FIFO order to maintain correctness and
-// recoverability from a crash.
-//
-class MemTableList {
- public:
-  // A list of memtables.
-  MemTableList() : size_(0), num_flush_not_started_(0),
-    commit_in_progress_(false),
-    flush_requested_(false) {
-    imm_flush_needed.Release_Store(nullptr);
-  }
-  ~MemTableList() {};
-
-  // so that backgrund threads can detect non-nullptr pointer to
-  // determine whether this is anything more to start flushing.
-  port::AtomicPointer imm_flush_needed;
-
-  // Increase reference count on all underling memtables
-  void RefAll();
-
-  // Drop reference count on all underling memtables
-  void UnrefAll();
-
-  // Returns the total number of memtables in the list
-  int size();
-
-  // Returns true if there is at least one memtable on which flush has
-  // not yet started.
-  bool IsFlushPending(int min_write_buffer_number_to_merge);
-
-  // Returns the earliest memtables that needs to be flushed.
-  void PickMemtablesToFlush(std::vector<MemTable*>* mems);
-
-  // Commit a successful flush in the manifest file
-  Status InstallMemtableFlushResults(const std::vector<MemTable*> &m,
-                      VersionSet* vset, Status flushStatus,
-                      port::Mutex* mu, Logger* info_log,
-                      uint64_t file_number,
-                      std::set<uint64_t>& pending_outputs);
-
-  // New memtables are inserted at the front of the list.
-  // Takes ownership of the referenced held on *m by the caller of Add().
-  void Add(MemTable* m);
-
-  // Returns an estimate of the number of bytes of data in use.
-  size_t ApproximateMemoryUsage();
-
-  // Search all the memtables starting from the most recent one.
-  // Return the most recent value found, if any.
-  bool Get(const LookupKey& key, std::string* value, Status* s,
-           std::deque<std::string>* operands, const Options& options);
-
-  // Returns the list of underlying memtables.
-  void GetMemTables(std::vector<MemTable*>* list);
-
-  // Request a flush of all existing memtables to storage
-  void FlushRequested() { flush_requested_ = true; }
-
-  // Copying allowed
-  // MemTableList(const MemTableList&);
-  // void operator=(const MemTableList&);
-
- private:
-  std::list<MemTable*> memlist_;
-  int size_;
-
-  // the number of elements that still need flushing
-  int num_flush_not_started_;
-
-  // committing in progress
-  bool commit_in_progress_;
-
-  // Requested a flush of all memtables to storage
-  bool flush_requested_;
-
-};
-
-}  // namespace rocksdb
-
-#endif  // STORAGE_LEVELDB_DB_MEMTABLELIST_H_

db/merge_context.h

@@ -0,0 +1,69 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+#pragma once
+#include "db/dbformat.h"
+#include "rocksdb/slice.h"
+#include <string>
+#include <deque>
+
+namespace rocksdb {
+
+const std::deque<std::string> empty_operand_list;
+
+// The merge context for merging a user key.
+// When doing a Get(), DB will create such a class and pass it when
+// issuing Get() operation to memtables and version_set. The operands
+// will be fetched from the context when issuing partial of full merge.
+class MergeContext {
+public:
+  // Clear all the operands
+  void Clear() {
+    if (operand_list) {
+      operand_list->clear();
+    }
+  }
+  // Replace all operands with merge_result, which are expected to be the
+  // merge result of them.
+  void PushPartialMergeResult(std::string& merge_result) {
+    assert (operand_list);
+    operand_list->clear();
+    operand_list->push_front(std::move(merge_result));
+  }
+  // Push a merge operand
+  void PushOperand(const Slice& operand_slice) {
+    Initialize();
+    operand_list->push_front(operand_slice.ToString());
+  }
+  // return total number of operands in the list
+  size_t GetNumOperands() const {
+    if (!operand_list) {
+      return 0;
+    }
+    return operand_list->size();
+  }
+  // Get the operand at the index.
+  Slice GetOperand(int index) const {
+    assert (operand_list);
+    return (*operand_list)[index];
+  }
+  // Return all the operands.
+  const std::deque<std::string>& GetOperands() const {
+    if (!operand_list) {
+      return empty_operand_list;
+    }
+    return *operand_list;
+  }
+private:
+  void Initialize() {
+    if (!operand_list) {
+      operand_list.reset(new std::deque<std::string>());
+    }
+  }
+  std::unique_ptr<std::deque<std::string>> operand_list;
+};
+
+} // namespace rocksdb
+

db/merge_helper.cc

@@ -1,8 +1,14 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 #include "merge_helper.h"
 #include "db/dbformat.h"
 #include "rocksdb/comparator.h"
 #include "rocksdb/db.h"
 #include "rocksdb/merge_operator.h"
+#include "util/statistics.h"
 #include <string>
 #include <stdio.h>
 
@@ -15,7 +21,7 @@ namespace rocksdb {
 //       operands_ stores the list of merge operands encountered while merging.
 //       keys_[i] corresponds to operands_[i] for each i.
 void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
-                             bool at_bottom, shared_ptr<Statistics> stats) {
+                             bool at_bottom, Statistics* stats, int* steps) {
   // Get a copy of the internal key, before it's invalidated by iter->Next()
   // Also maintain the list of merge operands seen.
   keys_.clear();
@@ -34,9 +40,12 @@ void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
   ParseInternalKey(keys_.back(), &orig_ikey);
 
   bool hit_the_next_user_key = false;
-  ParsedInternalKey ikey;
   std::string merge_result;  // Temporary value for merge results
+  if (steps) {
+    ++(*steps);
+  }
   for (iter->Next(); iter->Valid(); iter->Next()) {
+    ParsedInternalKey ikey;
     assert(operands_.size() >= 1);        // Should be invariants!
     assert(keys_.size() == operands_.size());
 
@@ -85,6 +94,9 @@ void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
 
       // move iter to the next entry (before doing anything else)
       iter->Next();
+      if (steps) {
+        ++(*steps);
+      }
       return;
     }
 
@@ -113,6 +125,9 @@ void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
 
       // move iter to the next entry
       iter->Next();
+      if (steps) {
+        ++(*steps);
+      }
       return;
     }
 
@@ -123,28 +138,13 @@ void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
       //   => then continue because we haven't yet seen a Put/Delete.
       assert(!operands_.empty()); // Should have at least one element in it
 
+      // keep queuing keys and operands until we either meet a put / delete
+      // request or later did a partial merge.
       keys_.push_front(iter->key().ToString());
       operands_.push_front(iter->value().ToString());
-      while (operands_.size() >= 2) {
-        // Returns false when the merge_operator can no longer process it
-        if (user_merge_operator_->PartialMerge(ikey.user_key,
-                                               Slice(operands_[0]),
-                                               Slice(operands_[1]),
-                                               &merge_result,
-                                               logger_)) {
-          // Merging of operands (associative merge) was successful.
-          // Replace these frontmost two operands with the merge result
-          keys_.pop_front();
-          operands_.pop_front();
-          swap(operands_.front(), merge_result);
-        } else {
-          // Merging of operands (associative merge) returned false.
-          // The user merge_operator does not know how to merge these operands.
-          // So we just stack them up until we find a Put/Delete or end of key.
-          break;
-        }
+      if (steps) {
+        ++(*steps);
       }
-      continue;
     }
   }
 
@@ -170,7 +170,7 @@ void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
     assert(kTypeMerge == orig_ikey.type);
     assert(operands_.size() >= 1);
     assert(operands_.size() == keys_.size());
-    success_ = user_merge_operator_->FullMerge(ikey.user_key, nullptr,
+    success_ = user_merge_operator_->FullMerge(orig_ikey.user_key, nullptr,
                                                operands_, &merge_result,
                                                logger_);
 
@@ -186,6 +186,23 @@ void MergeHelper::MergeUntil(Iterator* iter, SequenceNumber stop_before,
       RecordTick(stats, NUMBER_MERGE_FAILURES);
       // Do nothing if not success_. Leave keys() and operands() as they are.
     }
+  } else {
+    // We haven't seen the beginning of the key nor a Put/Delete.
+    // Attempt to use the user's associative merge function to
+    // merge the stacked merge operands into a single operand.
+
+    if (operands_.size() >= 2 &&
+        operands_.size() >= min_partial_merge_operands_ &&
+        user_merge_operator_->PartialMergeMulti(
+            orig_ikey.user_key,
+            std::deque<Slice>(operands_.begin(), operands_.end()),
+            &merge_result, logger_)) {
+      // Merging of operands (associative merge) was successful.
+      // Replace operands with the merge result
+      operands_.clear();
+      operands_.push_front(std::move(merge_result));
+      keys_.erase(keys_.begin(), keys_.end() - 1);
+    }
   }
 }
 

db/merge_helper.h

@@ -1,9 +1,13 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 #ifndef MERGE_HELPER_H
 #define MERGE_HELPER_H
 
 #include "db/dbformat.h"
 #include "rocksdb/slice.h"
-#include "rocksdb/statistics.h"
 #include <string>
 #include <deque>
 
@@ -13,16 +17,18 @@ class Comparator;
 class Iterator;
 class Logger;
 class MergeOperator;
+class Statistics;
 
 class MergeHelper {
  public:
   MergeHelper(const Comparator* user_comparator,
-              const MergeOperator* user_merge_operator,
-              Logger* logger,
+              const MergeOperator* user_merge_operator, Logger* logger,
+              unsigned min_partial_merge_operands,
               bool assert_valid_internal_key)
       : user_comparator_(user_comparator),
         user_merge_operator_(user_merge_operator),
         logger_(logger),
+        min_partial_merge_operands_(min_partial_merge_operands),
         assert_valid_internal_key_(assert_valid_internal_key),
         keys_(),
         operands_(),
@@ -41,7 +47,8 @@ class MergeHelper {
   // at_bottom:   (IN) true if the iterator covers the bottem level, which means
   //                   we could reach the start of the history of this user key.
   void MergeUntil(Iterator* iter, SequenceNumber stop_before = 0,
-                  bool at_bottom = false, shared_ptr<Statistics> stats=nullptr);
+                  bool at_bottom = false, Statistics* stats = nullptr,
+                  int* steps = nullptr);
 
   // Query the merge result
   // These are valid until the next MergeUntil call
@@ -83,7 +90,7 @@ class MergeHelper {
   const Comparator* user_comparator_;
   const MergeOperator* user_merge_operator_;
   Logger* logger_;
-  Iterator* iter_; // in: the internal iterator, positioned at the first merge entry
+  unsigned min_partial_merge_operands_;
   bool assert_valid_internal_key_; // enforce no internal key corruption?
 
   // the scratch area that holds the result of MergeUntil

db/merge_operator.cc

@@ -1,14 +1,41 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 /**
  * Back-end implementation details specific to the Merge Operator.
- *
- * @author Deon Nicholas (dnicholas@fb.com)
- * Copyright 2013 Facebook
  */
 
 #include "rocksdb/merge_operator.h"
 
 namespace rocksdb {
 
+// The default implementation of PartialMergeMulti, which invokes
+// PartialMerge multiple times internally and merges two operands at
+// a time.
+bool MergeOperator::PartialMergeMulti(const Slice& key,
+                                      const std::deque<Slice>& operand_list,
+                                      std::string* new_value,
+                                      Logger* logger) const {
+  assert(operand_list.size() >= 2);
+  // Simply loop through the operands
+  std::string temp_value;
+  Slice temp_slice(operand_list[0]);
+
+  for (size_t i = 1; i < operand_list.size(); ++i) {
+    auto& operand = operand_list[i];
+    if (!PartialMerge(key, temp_slice, operand, &temp_value, logger)) {
+      return false;
+    }
+    swap(temp_value, *new_value);
+    temp_slice = Slice(*new_value);
+  }
+
+  // The result will be in *new_value. All merges succeeded.
+  return true;
+}
+
 // Given a "real" merge from the library, call the user's
 // associative merge function one-by-one on each of the operands.
 // NOTE: It is assumed that the client's merge-operator will handle any errors.
@@ -44,7 +71,6 @@ bool AssociativeMergeOperator::PartialMerge(
     const Slice& right_operand,
     std::string* new_value,
     Logger* logger) const {
-
   return Merge(key, &left_operand, right_operand, new_value, logger);
 }
 

db/merge_test.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 #include <assert.h>
 #include <memory>
 #include <iostream>
@@ -9,26 +14,84 @@
 #include "rocksdb/merge_operator.h"
 #include "db/dbformat.h"
 #include "db/db_impl.h"
+#include "db/write_batch_internal.h"
 #include "utilities/merge_operators.h"
 #include "util/testharness.h"
-#include "utilities/utility_db.h"
+#include "utilities/db_ttl.h"
 
 using namespace std;
 using namespace rocksdb;
 
+namespace {
+  int numMergeOperatorCalls;
+  void resetNumMergeOperatorCalls() {
+    numMergeOperatorCalls = 0;
+  }
 
-std::shared_ptr<DB> OpenDb(const string& dbname, const bool ttl = false) {
+  int num_partial_merge_calls;
+  void resetNumPartialMergeCalls() {
+    num_partial_merge_calls = 0;
+  }
+}
+
+class CountMergeOperator : public AssociativeMergeOperator {
+ public:
+  CountMergeOperator() {
+    mergeOperator_ = MergeOperators::CreateUInt64AddOperator();
+  }
+
+  virtual bool Merge(const Slice& key,
+                     const Slice* existing_value,
+                     const Slice& value,
+                     std::string* new_value,
+                     Logger* logger) const override {
+    ++numMergeOperatorCalls;
+    if (existing_value == nullptr) {
+      new_value->assign(value.data(), value.size());
+      return true;
+    }
+
+    return mergeOperator_->PartialMerge(
+        key,
+        *existing_value,
+        value,
+        new_value,
+        logger);
+  }
+
+  virtual bool PartialMergeMulti(const Slice& key,
+                                 const std::deque<Slice>& operand_list,
+                                 std::string* new_value, Logger* logger) const {
+    ++num_partial_merge_calls;
+    return mergeOperator_->PartialMergeMulti(key, operand_list, new_value,
+                                             logger);
+  }
+
+  virtual const char* Name() const override {
+    return "UInt64AddOperator";
+  }
+
+ private:
+  std::shared_ptr<MergeOperator> mergeOperator_;
+};
+
+namespace {
+std::shared_ptr<DB> OpenDb(const string& dbname, const bool ttl = false,
+                           const size_t max_successive_merges = 0,
+                           const uint32_t min_partial_merge_operands = 2) {
   DB* db;
-  StackableDB* sdb;
   Options options;
   options.create_if_missing = true;
-  options.merge_operator = MergeOperators::CreateUInt64AddOperator();
+  options.merge_operator = std::make_shared<CountMergeOperator>();
+  options.max_successive_merges = max_successive_merges;
+  options.min_partial_merge_operands = min_partial_merge_operands;
   Status s;
   DestroyDB(dbname, Options());
   if (ttl) {
     cout << "Opening database with TTL\n";
-    s = UtilityDB::OpenTtlDB(options, dbname, &sdb);
-    db = sdb;
+    DBWithTTL* db_with_ttl;
+    s = DBWithTTL::Open(options, dbname, &db_with_ttl);
+    db = db_with_ttl;
   } else {
     s = DB::Open(options, dbname, &db);
   }
@@ -38,6 +101,7 @@ std::shared_ptr<DB> OpenDb(const string& dbname, const bool ttl = false) {
   }
   return std::shared_ptr<DB>(db);
 }
+}  // namespace
 
 // Imagine we are maintaining a set of uint64 counters.
 // Each counter has a distinct name. And we would like
@@ -85,7 +149,7 @@ class Counters {
     }
   }
 
-  // mapped to a leveldb Delete
+  // mapped to a rocksdb Delete
   bool remove(const string& key) {
     auto s = db_->Delete(delete_option_, key);
 
@@ -97,7 +161,7 @@ class Counters {
     }
   }
 
-  // mapped to a leveldb Get
+  // mapped to a rocksdb Get
   bool get(const string& key, uint64_t *value) {
     string str;
     auto s = db_->Get(get_option_, key, &str);
@@ -139,12 +203,16 @@ class Counters {
 
   uint64_t assert_get(const string& key) {
     uint64_t value = default_;
-    assert(get(key, &value));
+    int result = get(key, &value);
+    assert(result);
+    if (result == 0) exit(1); // Disable unused variable warning.
     return value;
   }
 
   void assert_add(const string& key, uint64_t value) {
-    assert(add(key, value));
+    int result = add(key, value);
+    assert(result);
+    if (result == 0) exit(1); // Disable unused variable warning. 
   }
 };
 
@@ -159,7 +227,7 @@ class MergeBasedCounters : public Counters {
         merge_option_() {
   }
 
-  // mapped to a leveldb Merge operation
+  // mapped to a rocksdb Merge operation
   virtual bool add(const string& key, uint64_t value) override {
     char encoded[sizeof(uint64_t)];
     EncodeFixed64(encoded, value);
@@ -175,6 +243,7 @@ class MergeBasedCounters : public Counters {
   }
 };
 
+namespace {
 void dumpDb(DB* db) {
   auto it = unique_ptr<Iterator>(db->NewIterator(ReadOptions()));
   for (it->SeekToFirst(); it->Valid(); it->Next()) {
@@ -238,6 +307,105 @@ void testCounters(Counters& counters, DB* db, bool test_compaction) {
   }
 }
 
+void testSuccessiveMerge(
+    Counters& counters, int max_num_merges, int num_merges) {
+
+  counters.assert_remove("z");
+  uint64_t sum = 0;
+
+  for (int i = 1; i <= num_merges; ++i) {
+    resetNumMergeOperatorCalls();
+    counters.assert_add("z", i);
+    sum += i;
+
+    if (i % (max_num_merges + 1) == 0) {
+      assert(numMergeOperatorCalls == max_num_merges + 1);
+    } else {
+      assert(numMergeOperatorCalls == 0);
+    }
+
+    resetNumMergeOperatorCalls();
+    assert(counters.assert_get("z") == sum);
+    assert(numMergeOperatorCalls == i % (max_num_merges + 1));
+  }
+}
+
+void testPartialMerge(Counters* counters, DB* db, int max_merge, int min_merge,
+                      int count) {
+  FlushOptions o;
+  o.wait = true;
+
+  // Test case 1: partial merge should be called when the number of merge
+  //              operands exceeds the threshold.
+  uint64_t tmp_sum = 0;
+  resetNumPartialMergeCalls();
+  for (int i = 1; i <= count; i++) {
+    counters->assert_add("b", i);
+    tmp_sum += i;
+  }
+  db->Flush(o);
+  db->CompactRange(nullptr, nullptr);
+  ASSERT_EQ(tmp_sum, counters->assert_get("b"));
+  if (count > max_merge) {
+    // in this case, FullMerge should be called instead.
+    ASSERT_EQ(num_partial_merge_calls, 0);
+  } else {
+    // if count >= min_merge, then partial merge should be called once.
+    ASSERT_EQ((count >= min_merge), (num_partial_merge_calls == 1));
+  }
+
+  // Test case 2: partial merge should not be called when a put is found.
+  resetNumPartialMergeCalls();
+  tmp_sum = 0;
+  db->Put(rocksdb::WriteOptions(), "c", "10");
+  for (int i = 1; i <= count; i++) {
+    counters->assert_add("c", i);
+    tmp_sum += i;
+  }
+  db->Flush(o);
+  db->CompactRange(nullptr, nullptr);
+  ASSERT_EQ(tmp_sum, counters->assert_get("c"));
+  ASSERT_EQ(num_partial_merge_calls, 0);
+}
+
+void testSingleBatchSuccessiveMerge(
+    DB* db,
+    int max_num_merges,
+    int num_merges) {
+  assert(num_merges > max_num_merges);
+
+  Slice key("BatchSuccessiveMerge");
+  uint64_t merge_value = 1;
+  Slice merge_value_slice((char *)&merge_value, sizeof(merge_value));
+
+  // Create the batch
+  WriteBatch batch;
+  for (int i = 0; i < num_merges; ++i) {
+    batch.Merge(key, merge_value_slice);
+  }
+
+  // Apply to memtable and count the number of merges
+  resetNumMergeOperatorCalls();
+  {
+    Status s = db->Write(WriteOptions(), &batch);
+    assert(s.ok());
+  }
+  assert(numMergeOperatorCalls ==
+      num_merges - (num_merges % (max_num_merges + 1)));
+
+  // Get the value
+  resetNumMergeOperatorCalls();
+  string get_value_str;
+  {
+    Status s = db->Get(ReadOptions(), key, &get_value_str);
+    assert(s.ok());
+  }
+  assert(get_value_str.size() == sizeof(uint64_t));
+  uint64_t get_value = DecodeFixed64(&get_value_str[0]);
+  ASSERT_EQ(get_value, num_merges * merge_value);
+  ASSERT_EQ(numMergeOperatorCalls, (num_merges % (max_num_merges + 1)));
+}
+
 void runTest(int argc, const string& dbname, const bool use_ttl = false) {
   auto db = OpenDb(dbname, use_ttl);
 
@@ -260,11 +428,45 @@ void runTest(int argc, const string& dbname, const bool use_ttl = false) {
   }
 
   DestroyDB(dbname, Options());
+  db.reset();
+
+  {
+    cout << "Test merge in memtable... \n";
+    size_t max_merge = 5;
+    auto db = OpenDb(dbname, use_ttl, max_merge);
+    MergeBasedCounters counters(db, 0);
+    testCounters(counters, db.get(), compact);
+    testSuccessiveMerge(counters, max_merge, max_merge * 2);
+    testSingleBatchSuccessiveMerge(db.get(), 5, 7);
+    DestroyDB(dbname, Options());
+  }
+
+  {
+    cout << "Test Partial-Merge\n";
+    size_t max_merge = 100;
+    for (uint32_t min_merge = 5; min_merge < 25; min_merge += 5) {
+      for (uint32_t count = min_merge - 1; count <= min_merge + 1; count++) {
+        auto db = OpenDb(dbname, use_ttl, max_merge, min_merge);
+        MergeBasedCounters counters(db, 0);
+        testPartialMerge(&counters, db.get(), max_merge, min_merge, count);
+        DestroyDB(dbname, Options());
+      }
+      {
+        auto db = OpenDb(dbname, use_ttl, max_merge, min_merge);
+        MergeBasedCounters counters(db, 0);
+        testPartialMerge(&counters, db.get(), max_merge, min_merge,
+                         min_merge * 10);
+        DestroyDB(dbname, Options());
+      }
+    }
+  }
 }
+}  // namespace
 
 int main(int argc, char *argv[]) {
   //TODO: Make this test like a general rocksdb unit-test
   runTest(argc, test::TmpDir() + "/merge_testdb");
   runTest(argc, test::TmpDir() + "/merge_testdbttl", true); // Run test on TTL database
+  printf("Passed all tests!\n");
   return 0;
 }

db/perf_context_test.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 #include <algorithm>
 #include <iostream>
 #include <vector>
@@ -5,6 +10,8 @@
 
 #include "rocksdb/db.h"
 #include "rocksdb/perf_context.h"
+#include "rocksdb/slice_transform.h"
+#include "rocksdb/memtablerep.h"
 #include "util/histogram.h"
 #include "util/stop_watch.h"
 #include "util/testharness.h"
@@ -20,16 +27,6 @@ int FLAGS_min_write_buffer_number_to_merge = 7;
 // Path to the database on file system
 const std::string kDbName = rocksdb::test::TmpDir() + "/perf_context_test";
 
-void SeekToFirst(rocksdb::Iterator* iter) {
-//  std::cout << "Press a key to continue:";
-//  std::string s;
-//  std::cin >> s;
-  iter->SeekToFirst();
-//  std::cout << "Press a key to continue:";
-//  std::string s2;
-//  std::cin >> s2;
-}
-
 namespace rocksdb {
 
 std::shared_ptr<DB> OpenDb() {
@@ -43,8 +40,8 @@ std::shared_ptr<DB> OpenDb() {
 
     if (FLAGS_use_set_based_memetable) {
       auto prefix_extractor = rocksdb::NewFixedPrefixTransform(0);
-      options.memtable_factory =
-        std::make_shared<rocksdb::PrefixHashRepFactory>(prefix_extractor);
+      options.memtable_factory.reset(
+          NewHashSkipListRepFactory(prefix_extractor));
     }
 
     Status s = DB::Open(options, kDbName,  &db);
@@ -95,10 +92,7 @@ TEST(PerfContextTest, SeekIntoDeletion) {
 
   perf_context.Reset();
   StopWatchNano timer(Env::Default(), true);
-  //CALLGRIND_ZERO_STATS;
-  SeekToFirst(iter.get());
-  //iter->SeekToFirst();
-  //CALLGRIND_DUMP_STATS;
+  iter->SeekToFirst();
   hist_seek_to_first.Add(perf_context.user_key_comparison_count);
   auto elapsed_nanos = timer.ElapsedNanos();
 
@@ -182,6 +176,13 @@ void ProfileKeyComparison() {
 
   HistogramImpl hist_put;
   HistogramImpl hist_get;
+  HistogramImpl hist_get_snapshot;
+  HistogramImpl hist_get_memtable;
+  HistogramImpl hist_get_post_process;
+  HistogramImpl hist_num_memtable_checked;
+  HistogramImpl hist_write_pre_post;
+  HistogramImpl hist_write_wal_time;
+  HistogramImpl hist_write_memtable_time;
 
   std::cout << "Inserting " << FLAGS_total_keys << " key/value pairs\n...\n";
 
@@ -200,16 +201,37 @@ void ProfileKeyComparison() {
 
     perf_context.Reset();
     db->Put(write_options, key, value);
+    hist_write_pre_post.Add(perf_context.write_pre_and_post_process_time);
+    hist_write_wal_time.Add(perf_context.write_wal_time);
+    hist_write_memtable_time.Add(perf_context.write_memtable_time);
     hist_put.Add(perf_context.user_key_comparison_count);
 
     perf_context.Reset();
     db->Get(read_options, key, &value);
+    hist_get_snapshot.Add(perf_context.get_snapshot_time);
+    hist_get_memtable.Add(perf_context.get_from_memtable_time);
+    hist_num_memtable_checked.Add(perf_context.get_from_memtable_count);
+    hist_get_post_process.Add(perf_context.get_post_process_time);
     hist_get.Add(perf_context.user_key_comparison_count);
   }
 
   std::cout << "Put uesr key comparison: \n" << hist_put.ToString()
             << "Get uesr key comparison: \n" << hist_get.ToString();
+  std::cout << "Put(): Pre and Post Process Time: \n"
+            << hist_write_pre_post.ToString()
+            << " Writing WAL time: \n"
+            << hist_write_wal_time.ToString() << "\n"
+            << " Writing Mem Table time: \n"
+            << hist_write_memtable_time.ToString() << "\n";
 
+  std::cout << "Get(): Time to get snapshot: \n"
+            << hist_get_snapshot.ToString()
+            << " Time to get value from memtables: \n"
+            << hist_get_memtable.ToString() << "\n"
+            << " Number of memtables checked: \n"
+            << hist_num_memtable_checked.ToString() << "\n"
+            << " Time to post process: \n"
+            << hist_get_post_process.ToString() << "\n";
 }
 
 TEST(PerfContextTest, KeyComparisonCount) {
@@ -224,7 +246,7 @@ TEST(PerfContextTest, KeyComparisonCount) {
 }
 
 // make perf_context_test
-// export LEVELDB_TESTS=PerfContextTest.SeekKeyComparison
+// export ROCKSDB_TESTS=PerfContextTest.SeekKeyComparison
 // For one memtable:
 // ./perf_context_test --write_buffer_size=500000 --total_keys=10000
 // For two memtables:
@@ -252,13 +274,29 @@ TEST(PerfContextTest, SeekKeyComparison) {
     std::random_shuffle(keys.begin(), keys.end());
   }
 
+  HistogramImpl hist_put_time;
+  HistogramImpl hist_wal_time;
+  HistogramImpl hist_time_diff;
+
+  SetPerfLevel(kEnableTime);
+  StopWatchNano timer(Env::Default());
   for (const int i : keys) {
     std::string key = "k" + std::to_string(i);
     std::string value = "v" + std::to_string(i);
 
+    perf_context.Reset();
+    timer.Start();
     db->Put(write_options, key, value);
+    auto put_time = timer.ElapsedNanos();
+    hist_put_time.Add(put_time);
+    hist_wal_time.Add(perf_context.write_wal_time);
+    hist_time_diff.Add(put_time - perf_context.write_wal_time);
   }
 
+  std::cout << "Put time:\n" << hist_put_time.ToString()
+            << "WAL time:\n" << hist_wal_time.ToString()
+            << "time diff:\n" << hist_time_diff.ToString();
+
   HistogramImpl hist_seek;
   HistogramImpl hist_next;
 

db/plain_table_db_test.cc

@@ -0,0 +1,962 @@
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+#include <algorithm>
+#include <set>
+
+#include "db/db_impl.h"
+#include "db/filename.h"
+#include "db/version_set.h"
+#include "db/write_batch_internal.h"
+#include "rocksdb/cache.h"
+#include "rocksdb/compaction_filter.h"
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"
+#include "rocksdb/filter_policy.h"
+#include "rocksdb/slice_transform.h"
+#include "rocksdb/table.h"
+#include "table/meta_blocks.h"
+#include "table/plain_table_factory.h"
+#include "table/plain_table_reader.h"
+#include "util/hash.h"
+#include "util/logging.h"
+#include "util/mutexlock.h"
+#include "util/testharness.h"
+#include "util/testutil.h"
+#include "utilities/merge_operators.h"
+
+using std::unique_ptr;
+
+namespace rocksdb {
+
+class PlainTableDBTest {
+ protected:
+ private:
+  std::string dbname_;
+  Env* env_;
+  DB* db_;
+
+  Options last_options_;
+
+ public:
+  PlainTableDBTest() : env_(Env::Default()) {
+    dbname_ = test::TmpDir() + "/plain_table_db_test";
+    ASSERT_OK(DestroyDB(dbname_, Options()));
+    db_ = nullptr;
+    Reopen();
+  }
+
+  ~PlainTableDBTest() {
+    delete db_;
+    ASSERT_OK(DestroyDB(dbname_, Options()));
+  }
+
+  // Return the current option configuration.
+  Options CurrentOptions() {
+    Options options;
+    options.table_factory.reset(NewPlainTableFactory(0, 2, 0.8, 3, 0, kPrefix));
+    options.memtable_factory.reset(NewHashLinkListRepFactory(4, 0, 3, true, 3));
+    options.prefix_extractor.reset(NewFixedPrefixTransform(8));
+    options.allow_mmap_reads = true;
+    return options;
+  }
+
+  DBImpl* dbfull() {
+    return reinterpret_cast<DBImpl*>(db_);
+  }
+
+  void Reopen(Options* options = nullptr) {
+    ASSERT_OK(TryReopen(options));
+  }
+
+  void Close() {
+    delete db_;
+    db_ = nullptr;
+  }
+
+  void DestroyAndReopen(Options* options = nullptr) {
+    //Destroy using last options
+    Destroy(&last_options_);
+    ASSERT_OK(TryReopen(options));
+  }
+
+  void Destroy(Options* options) {
+    delete db_;
+    db_ = nullptr;
+    ASSERT_OK(DestroyDB(dbname_, *options));
+  }
+
+  Status PureReopen(Options* options, DB** db) {
+    return DB::Open(*options, dbname_, db);
+  }
+
+  Status TryReopen(Options* options = nullptr) {
+    delete db_;
+    db_ = nullptr;
+    Options opts;
+    if (options != nullptr) {
+      opts = *options;
+    } else {
+      opts = CurrentOptions();
+      opts.create_if_missing = true;
+    }
+    last_options_ = opts;
+
+    return DB::Open(opts, dbname_, &db_);
+  }
+
+  Status Put(const Slice& k, const Slice& v) {
+    return db_->Put(WriteOptions(), k, v);
+  }
+
+  Status Delete(const std::string& k) {
+    return db_->Delete(WriteOptions(), k);
+  }
+
+  std::string Get(const std::string& k, const Snapshot* snapshot = nullptr) {
+    ReadOptions options;
+    options.snapshot = snapshot;
+    std::string result;
+    Status s = db_->Get(options, k, &result);
+    if (s.IsNotFound()) {
+      result = "NOT_FOUND";
+    } else if (!s.ok()) {
+      result = s.ToString();
+    }
+    return result;
+  }
+
+
+  int NumTableFilesAtLevel(int level) {
+    std::string property;
+    ASSERT_TRUE(
+        db_->GetProperty("rocksdb.num-files-at-level" + NumberToString(level),
+                         &property));
+    return atoi(property.c_str());
+  }
+
+  // Return spread of files per level
+  std::string FilesPerLevel() {
+    std::string result;
+    int last_non_zero_offset = 0;
+    for (int level = 0; level < db_->NumberLevels(); level++) {
+      int f = NumTableFilesAtLevel(level);
+      char buf[100];
+      snprintf(buf, sizeof(buf), "%s%d", (level ? "," : ""), f);
+      result += buf;
+      if (f > 0) {
+        last_non_zero_offset = result.size();
+      }
+    }
+    result.resize(last_non_zero_offset);
+    return result;
+  }
+
+  std::string IterStatus(Iterator* iter) {
+    std::string result;
+    if (iter->Valid()) {
+      result = iter->key().ToString() + "->" + iter->value().ToString();
+    } else {
+      result = "(invalid)";
+    }
+    return result;
+  }
+};
+
+TEST(PlainTableDBTest, Empty) {
+  ASSERT_TRUE(dbfull() != nullptr);
+  ASSERT_EQ("NOT_FOUND", Get("0000000000000foo"));
+}
+
+class TestPlainTableReader : public PlainTableReader {
+ public:
+  TestPlainTableReader(const EnvOptions& storage_options,
+                       const InternalKeyComparator& icomparator,
+                       EncodingType encoding_type, uint64_t file_size,
+                       int bloom_bits_per_key, double hash_table_ratio,
+                       size_t index_sparseness,
+                       const TableProperties* table_properties,
+                       unique_ptr<RandomAccessFile>&& file,
+                       const Options& options, bool* expect_bloom_not_match)
+      : PlainTableReader(options, std::move(file), storage_options, icomparator,
+                         encoding_type, file_size, table_properties),
+        expect_bloom_not_match_(expect_bloom_not_match) {
+    Status s = MmapDataFile();
+    ASSERT_TRUE(s.ok());
+
+    s = PopulateIndex(const_cast<TableProperties*>(table_properties),
+                      bloom_bits_per_key, hash_table_ratio, index_sparseness,
+                      2 * 1024 * 1024);
+    ASSERT_TRUE(s.ok());
+  }
+
+  virtual ~TestPlainTableReader() {}
+
+ private:
+  virtual bool MatchBloom(uint32_t hash) const override {
+    bool ret = PlainTableReader::MatchBloom(hash);
+    ASSERT_TRUE(!*expect_bloom_not_match_ || !ret);
+    return ret;
+  }
+  bool* expect_bloom_not_match_;
+};
+
+extern const uint64_t kPlainTableMagicNumber;
+class TestPlainTableFactory : public PlainTableFactory {
+ public:
+  explicit TestPlainTableFactory(bool* expect_bloom_not_match,
+                                 uint32_t user_key_len, int bloom_bits_per_key,
+                                 double hash_table_ratio,
+                                 size_t index_sparseness,
+                                 size_t huge_page_tlb_size,
+                                 EncodingType encoding_type)
+      : PlainTableFactory(user_key_len, bloom_bits_per_key, hash_table_ratio,
+                          index_sparseness, huge_page_tlb_size, encoding_type),
+        bloom_bits_per_key_(bloom_bits_per_key),
+        hash_table_ratio_(hash_table_ratio),
+        index_sparseness_(index_sparseness),
+        expect_bloom_not_match_(expect_bloom_not_match) {}
+
+  Status NewTableReader(const Options& options, const EnvOptions& soptions,
+                        const InternalKeyComparator& internal_comparator,
+                        unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
+                        unique_ptr<TableReader>* table) const override {
+    TableProperties* props = nullptr;
+    auto s = ReadTableProperties(file.get(), file_size, kPlainTableMagicNumber,
+                                 options.env, options.info_log.get(), &props);
+    ASSERT_TRUE(s.ok());
+
+    auto& user_props = props->user_collected_properties;
+    auto encoding_type_prop =
+        user_props.find(PlainTablePropertyNames::kEncodingType);
+    assert(encoding_type_prop != user_props.end());
+    EncodingType encoding_type = static_cast<EncodingType>(
+        DecodeFixed32(encoding_type_prop->second.c_str()));
+
+    std::unique_ptr<PlainTableReader> new_reader(new TestPlainTableReader(
+        soptions, internal_comparator, encoding_type, file_size,
+        bloom_bits_per_key_, hash_table_ratio_, index_sparseness_, props,
+        std::move(file), options, expect_bloom_not_match_));
+
+    *table = std::move(new_reader);
+    return s;
+  }
+
+ private:
+  int bloom_bits_per_key_;
+  double hash_table_ratio_;
+  size_t index_sparseness_;
+  bool* expect_bloom_not_match_;
+};
+
+TEST(PlainTableDBTest, Flush) {
+  for (size_t huge_page_tlb_size = 0; huge_page_tlb_size <= 2 * 1024 * 1024;
+       huge_page_tlb_size += 2 * 1024 * 1024) {
+    for (EncodingType encoding_type : {kPlain, kPrefix}) {
+    for (int bloom_bits = 0; bloom_bits <= 117; bloom_bits += 117) {
+      for (int total_order = 0; total_order <= 1; total_order++) {
+        Options options = CurrentOptions();
+        options.create_if_missing = true;
+        // Set only one bucket to force bucket conflict.
+        // Test index interval for the same prefix to be 1, 2 and 4
+        if (total_order) {
+          options.prefix_extractor.reset();
+          options.table_factory.reset(NewPlainTableFactory(
+              0, bloom_bits, 0, 2, huge_page_tlb_size, encoding_type));
+        } else {
+          options.table_factory.reset(NewPlainTableFactory(
+              0, bloom_bits, 0.75, 16, huge_page_tlb_size, encoding_type));
+        }
+        DestroyAndReopen(&options);
+
+        ASSERT_OK(Put("1000000000000foo", "v1"));
+        ASSERT_OK(Put("0000000000000bar", "v2"));
+        ASSERT_OK(Put("1000000000000foo", "v3"));
+        dbfull()->TEST_FlushMemTable();
+
+        TablePropertiesCollection ptc;
+        reinterpret_cast<DB*>(dbfull())->GetPropertiesOfAllTables(&ptc);
+        ASSERT_EQ(1U, ptc.size());
+        auto row = ptc.begin();
+        auto tp = row->second;
+        ASSERT_EQ(total_order ? "4" : "12", (tp->user_collected_properties).at(
+                                                "plain_table_hash_table_size"));
+        ASSERT_EQ("0", (tp->user_collected_properties)
+                           .at("plain_table_sub_index_size"));
+
+        ASSERT_EQ("v3", Get("1000000000000foo"));
+        ASSERT_EQ("v2", Get("0000000000000bar"));
+      }
+    }
+    }
+  }
+}
+
+TEST(PlainTableDBTest, Flush2) {
+  for (size_t huge_page_tlb_size = 0; huge_page_tlb_size <= 2 * 1024 * 1024;
+       huge_page_tlb_size += 2 * 1024 * 1024) {
+    for (EncodingType encoding_type : {kPlain, kPrefix}) {
+    for (int bloom_bits = 0; bloom_bits <= 117; bloom_bits += 117) {
+      for (int total_order = 0; total_order <= 1; total_order++) {
+        if (encoding_type == kPrefix && total_order == 1) {
+          continue;
+        }
+        bool expect_bloom_not_match = false;
+        Options options = CurrentOptions();
+        options.create_if_missing = true;
+        // Set only one bucket to force bucket conflict.
+        // Test index interval for the same prefix to be 1, 2 and 4
+        if (total_order) {
+          options.prefix_extractor = nullptr;
+          options.table_factory.reset(new TestPlainTableFactory(
+              &expect_bloom_not_match, 0, bloom_bits, 0, 2, huge_page_tlb_size,
+              encoding_type));
+        } else {
+          options.table_factory.reset(new TestPlainTableFactory(
+              &expect_bloom_not_match, 0, bloom_bits, 0.75, 16,
+              huge_page_tlb_size, encoding_type));
+        }
+        DestroyAndReopen(&options);
+        ASSERT_OK(Put("0000000000000bar", "b"));
+        ASSERT_OK(Put("1000000000000foo", "v1"));
+        dbfull()->TEST_FlushMemTable();
+
+        ASSERT_OK(Put("1000000000000foo", "v2"));
+        dbfull()->TEST_FlushMemTable();
+        ASSERT_EQ("v2", Get("1000000000000foo"));
+
+        ASSERT_OK(Put("0000000000000eee", "v3"));
+        dbfull()->TEST_FlushMemTable();
+        ASSERT_EQ("v3", Get("0000000000000eee"));
+
+        ASSERT_OK(Delete("0000000000000bar"));
+        dbfull()->TEST_FlushMemTable();
+        ASSERT_EQ("NOT_FOUND", Get("0000000000000bar"));
+
+        ASSERT_OK(Put("0000000000000eee", "v5"));
+        ASSERT_OK(Put("9000000000000eee", "v5"));
+        dbfull()->TEST_FlushMemTable();
+        ASSERT_EQ("v5", Get("0000000000000eee"));
+
+        // Test Bloom Filter
+        if (bloom_bits > 0) {
+          // Neither key nor value should exist.
+          expect_bloom_not_match = true;
+          ASSERT_EQ("NOT_FOUND", Get("5_not00000000bar"));
+
+          // Key doesn't exist any more but prefix exists.
+          if (total_order) {
+            ASSERT_EQ("NOT_FOUND", Get("1000000000000not"));
+            ASSERT_EQ("NOT_FOUND", Get("0000000000000not"));
+          }
+          expect_bloom_not_match = false;
+        }
+      }
+    }
+    }
+  }
+}
+
+TEST(PlainTableDBTest, Iterator) {
+  for (size_t huge_page_tlb_size = 0; huge_page_tlb_size <= 2 * 1024 * 1024;
+       huge_page_tlb_size += 2 * 1024 * 1024) {
+    for (EncodingType encoding_type : {kPlain, kPrefix}) {
+    for (int bloom_bits = 0; bloom_bits <= 117; bloom_bits += 117) {
+      for (int total_order = 0; total_order <= 1; total_order++) {
+        if (encoding_type == kPrefix && total_order == 1) {
+          continue;
+        }
+        bool expect_bloom_not_match = false;
+        Options options = CurrentOptions();
+        options.create_if_missing = true;
+        // Set only one bucket to force bucket conflict.
+        // Test index interval for the same prefix to be 1, 2 and 4
+        if (total_order) {
+          options.prefix_extractor = nullptr;
+          options.table_factory.reset(new TestPlainTableFactory(
+              &expect_bloom_not_match, 16, bloom_bits, 0, 2, huge_page_tlb_size,
+              encoding_type));
+        } else {
+          options.table_factory.reset(new TestPlainTableFactory(
+              &expect_bloom_not_match, 16, bloom_bits, 0.75, 16,
+              huge_page_tlb_size, encoding_type));
+        }
+        DestroyAndReopen(&options);
+
+        ASSERT_OK(Put("1000000000foo002", "v_2"));
+        ASSERT_OK(Put("0000000000000bar", "random"));
+        ASSERT_OK(Put("1000000000foo001", "v1"));
+        ASSERT_OK(Put("3000000000000bar", "bar_v"));
+        ASSERT_OK(Put("1000000000foo003", "v__3"));
+        ASSERT_OK(Put("1000000000foo004", "v__4"));
+        ASSERT_OK(Put("1000000000foo005", "v__5"));
+        ASSERT_OK(Put("1000000000foo007", "v__7"));
+        ASSERT_OK(Put("1000000000foo008", "v__8"));
+        dbfull()->TEST_FlushMemTable();
+        ASSERT_EQ("v1", Get("1000000000foo001"));
+        ASSERT_EQ("v__3", Get("1000000000foo003"));
+        Iterator* iter = dbfull()->NewIterator(ReadOptions());
+        iter->Seek("1000000000foo000");
+        ASSERT_TRUE(iter->Valid());
+        ASSERT_EQ("1000000000foo001", iter->key().ToString());
+        ASSERT_EQ("v1", iter->value().ToString());
+
+        iter->Next();
+        ASSERT_TRUE(iter->Valid());
+        ASSERT_EQ("1000000000foo002", iter->key().ToString());
+        ASSERT_EQ("v_2", iter->value().ToString());
+
+        iter->Next();
+        ASSERT_TRUE(iter->Valid());
+        ASSERT_EQ("1000000000foo003", iter->key().ToString());
+        ASSERT_EQ("v__3", iter->value().ToString());
+
+        iter->Next();
+        ASSERT_TRUE(iter->Valid());
+        ASSERT_EQ("1000000000foo004", iter->key().ToString());
+        ASSERT_EQ("v__4", iter->value().ToString());
+
+        iter->Seek("3000000000000bar");
+        ASSERT_TRUE(iter->Valid());
+        ASSERT_EQ("3000000000000bar", iter->key().ToString());
+        ASSERT_EQ("bar_v", iter->value().ToString());
+
+        iter->Seek("1000000000foo000");
+        ASSERT_TRUE(iter->Valid());
+        ASSERT_EQ("1000000000foo001", iter->key().ToString());
+        ASSERT_EQ("v1", iter->value().ToString());
+
+        iter->Seek("1000000000foo005");
+        ASSERT_TRUE(iter->Valid());
+        ASSERT_EQ("1000000000foo005", iter->key().ToString());
+        ASSERT_EQ("v__5", iter->value().ToString());
+
+        iter->Seek("1000000000foo006");
+        ASSERT_TRUE(iter->Valid());
+        ASSERT_EQ("1000000000foo007", iter->key().ToString());
+        ASSERT_EQ("v__7", iter->value().ToString());
+
+        iter->Seek("1000000000foo008");
+        ASSERT_TRUE(iter->Valid());
+        ASSERT_EQ("1000000000foo008", iter->key().ToString());
+        ASSERT_EQ("v__8", iter->value().ToString());
+
+        if (total_order == 0) {
+          iter->Seek("1000000000foo009");
+          ASSERT_TRUE(iter->Valid());
+          ASSERT_EQ("3000000000000bar", iter->key().ToString());
+        }
+
+        // Test Bloom Filter
+        if (bloom_bits > 0) {
+          if (!total_order) {
+            // Neither key nor value should exist.
+            expect_bloom_not_match = true;
+            iter->Seek("2not000000000bar");
+            ASSERT_TRUE(!iter->Valid());
+            ASSERT_EQ("NOT_FOUND", Get("2not000000000bar"));
+            expect_bloom_not_match = false;
+          } else {
+            expect_bloom_not_match = true;
+            ASSERT_EQ("NOT_FOUND", Get("2not000000000bar"));
+            expect_bloom_not_match = false;
+          }
+        }
+
+        delete iter;
+      }
+    }
+    }
+  }
+}
+
+namespace {
+std::string MakeLongKey(size_t length, char c) {
+  return std::string(length, c);
+}
+}  // namespace
+
+TEST(PlainTableDBTest, IteratorLargeKeys) {
+  Options options = CurrentOptions();
+  options.table_factory.reset(NewPlainTableFactory(0, 0, 0));
+  options.create_if_missing = true;
+  options.prefix_extractor.reset();
+  DestroyAndReopen(&options);
+
+  std::string key_list[] = {
+      MakeLongKey(30, '0'),
+      MakeLongKey(16, '1'),
+      MakeLongKey(32, '2'),
+      MakeLongKey(60, '3'),
+      MakeLongKey(90, '4'),
+      MakeLongKey(50, '5'),
+      MakeLongKey(26, '6')
+  };
+
+  for (size_t i = 0; i < 7; i++) {
+    ASSERT_OK(Put(key_list[i], std::to_string(i)));
+  }
+
+  dbfull()->TEST_FlushMemTable();
+
+  Iterator* iter = dbfull()->NewIterator(ReadOptions());
+  iter->Seek(key_list[0]);
+
+  for (size_t i = 0; i < 7; i++) {
+    ASSERT_TRUE(iter->Valid());
+    ASSERT_EQ(key_list[i], iter->key().ToString());
+    ASSERT_EQ(std::to_string(i), iter->value().ToString());
+    iter->Next();
+  }
+
+  ASSERT_TRUE(!iter->Valid());
+
+  delete iter;
+}
+
+namespace {
+std::string MakeLongKeyWithPrefix(size_t length, char c) {
+  return "00000000" + std::string(length - 8, c);
+}
+}  // namespace
+
+TEST(PlainTableDBTest, IteratorLargeKeysWithPrefix) {
+  Options options = CurrentOptions();
+  options.table_factory.reset(NewPlainTableFactory(16, 0, 0.8, 3, 0, kPrefix));
+  options.create_if_missing = true;
+  DestroyAndReopen(&options);
+
+  std::string key_list[] = {
+      MakeLongKeyWithPrefix(30, '0'), MakeLongKeyWithPrefix(16, '1'),
+      MakeLongKeyWithPrefix(32, '2'), MakeLongKeyWithPrefix(60, '3'),
+      MakeLongKeyWithPrefix(90, '4'), MakeLongKeyWithPrefix(50, '5'),
+      MakeLongKeyWithPrefix(26, '6')};
+
+  for (size_t i = 0; i < 7; i++) {
+    ASSERT_OK(Put(key_list[i], std::to_string(i)));
+  }
+
+  dbfull()->TEST_FlushMemTable();
+
+  Iterator* iter = dbfull()->NewIterator(ReadOptions());
+  iter->Seek(key_list[0]);
+
+  for (size_t i = 0; i < 7; i++) {
+    ASSERT_TRUE(iter->Valid());
+    ASSERT_EQ(key_list[i], iter->key().ToString());
+    ASSERT_EQ(std::to_string(i), iter->value().ToString());
+    iter->Next();
+  }
+
+  ASSERT_TRUE(!iter->Valid());
+
+  delete iter;
+}
+
+// A test comparator which compare two strings in this way:
+// (1) first compare prefix of 8 bytes in alphabet order,
+// (2) if two strings share the same prefix, sort the other part of the string
+//     in the reverse alphabet order.
+class SimpleSuffixReverseComparator : public Comparator {
+ public:
+  SimpleSuffixReverseComparator() {}
+
+  virtual const char* Name() const { return "SimpleSuffixReverseComparator"; }
+
+  virtual int Compare(const Slice& a, const Slice& b) const {
+    Slice prefix_a = Slice(a.data(), 8);
+    Slice prefix_b = Slice(b.data(), 8);
+    int prefix_comp = prefix_a.compare(prefix_b);
+    if (prefix_comp != 0) {
+      return prefix_comp;
+    } else {
+      Slice suffix_a = Slice(a.data() + 8, a.size() - 8);
+      Slice suffix_b = Slice(b.data() + 8, b.size() - 8);
+      return -(suffix_a.compare(suffix_b));
+    }
+  }
+  virtual void FindShortestSeparator(std::string* start,
+                                     const Slice& limit) const {}
+
+  virtual void FindShortSuccessor(std::string* key) const {}
+};
+
+TEST(PlainTableDBTest, IteratorReverseSuffixComparator) {
+  Options options = CurrentOptions();
+  options.create_if_missing = true;
+  // Set only one bucket to force bucket conflict.
+  // Test index interval for the same prefix to be 1, 2 and 4
+  SimpleSuffixReverseComparator comp;
+  options.comparator = &comp;
+  DestroyAndReopen(&options);
+
+  ASSERT_OK(Put("1000000000foo002", "v_2"));
+  ASSERT_OK(Put("0000000000000bar", "random"));
+  ASSERT_OK(Put("1000000000foo001", "v1"));
+  ASSERT_OK(Put("3000000000000bar", "bar_v"));
+  ASSERT_OK(Put("1000000000foo003", "v__3"));
+  ASSERT_OK(Put("1000000000foo004", "v__4"));
+  ASSERT_OK(Put("1000000000foo005", "v__5"));
+  ASSERT_OK(Put("1000000000foo007", "v__7"));
+  ASSERT_OK(Put("1000000000foo008", "v__8"));
+  dbfull()->TEST_FlushMemTable();
+  ASSERT_EQ("v1", Get("1000000000foo001"));
+  ASSERT_EQ("v__3", Get("1000000000foo003"));
+  Iterator* iter = dbfull()->NewIterator(ReadOptions());
+  iter->Seek("1000000000foo009");
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("1000000000foo008", iter->key().ToString());
+  ASSERT_EQ("v__8", iter->value().ToString());
+
+  iter->Next();
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("1000000000foo007", iter->key().ToString());
+  ASSERT_EQ("v__7", iter->value().ToString());
+
+  iter->Next();
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("1000000000foo005", iter->key().ToString());
+  ASSERT_EQ("v__5", iter->value().ToString());
+
+  iter->Next();
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("1000000000foo004", iter->key().ToString());
+  ASSERT_EQ("v__4", iter->value().ToString());
+
+  iter->Seek("3000000000000bar");
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("3000000000000bar", iter->key().ToString());
+  ASSERT_EQ("bar_v", iter->value().ToString());
+
+  iter->Seek("1000000000foo005");
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("1000000000foo005", iter->key().ToString());
+  ASSERT_EQ("v__5", iter->value().ToString());
+
+  iter->Seek("1000000000foo006");
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("1000000000foo005", iter->key().ToString());
+  ASSERT_EQ("v__5", iter->value().ToString());
+
+  iter->Seek("1000000000foo008");
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("1000000000foo008", iter->key().ToString());
+  ASSERT_EQ("v__8", iter->value().ToString());
+
+  iter->Seek("1000000000foo000");
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("3000000000000bar", iter->key().ToString());
+
+  delete iter;
+}
+
+TEST(PlainTableDBTest, HashBucketConflict) {
+  for (size_t huge_page_tlb_size = 0; huge_page_tlb_size <= 2 * 1024 * 1024;
+       huge_page_tlb_size += 2 * 1024 * 1024) {
+    for (unsigned char i = 1; i <= 3; i++) {
+      Options options = CurrentOptions();
+      options.create_if_missing = true;
+      // Set only one bucket to force bucket conflict.
+      // Test index interval for the same prefix to be 1, 2 and 4
+      options.table_factory.reset(
+          NewPlainTableFactory(16, 0, 0, 2 ^ i, huge_page_tlb_size));
+      DestroyAndReopen(&options);
+      ASSERT_OK(Put("5000000000000fo0", "v1"));
+      ASSERT_OK(Put("5000000000000fo1", "v2"));
+      ASSERT_OK(Put("5000000000000fo2", "v"));
+      ASSERT_OK(Put("2000000000000fo0", "v3"));
+      ASSERT_OK(Put("2000000000000fo1", "v4"));
+      ASSERT_OK(Put("2000000000000fo2", "v"));
+      ASSERT_OK(Put("2000000000000fo3", "v"));
+
+      dbfull()->TEST_FlushMemTable();
+
+      ASSERT_EQ("v1", Get("5000000000000fo0"));
+      ASSERT_EQ("v2", Get("5000000000000fo1"));
+      ASSERT_EQ("v3", Get("2000000000000fo0"));
+      ASSERT_EQ("v4", Get("2000000000000fo1"));
+
+      ASSERT_EQ("NOT_FOUND", Get("5000000000000bar"));
+      ASSERT_EQ("NOT_FOUND", Get("2000000000000bar"));
+      ASSERT_EQ("NOT_FOUND", Get("5000000000000fo8"));
+      ASSERT_EQ("NOT_FOUND", Get("2000000000000fo8"));
+
+      ReadOptions ro;
+      Iterator* iter = dbfull()->NewIterator(ro);
+
+      iter->Seek("5000000000000fo0");
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("5000000000000fo0", iter->key().ToString());
+      iter->Next();
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("5000000000000fo1", iter->key().ToString());
+
+      iter->Seek("5000000000000fo1");
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("5000000000000fo1", iter->key().ToString());
+
+      iter->Seek("2000000000000fo0");
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("2000000000000fo0", iter->key().ToString());
+      iter->Next();
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("2000000000000fo1", iter->key().ToString());
+
+      iter->Seek("2000000000000fo1");
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("2000000000000fo1", iter->key().ToString());
+
+      iter->Seek("2000000000000bar");
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("2000000000000fo0", iter->key().ToString());
+
+      iter->Seek("5000000000000bar");
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("5000000000000fo0", iter->key().ToString());
+
+      iter->Seek("2000000000000fo8");
+      ASSERT_TRUE(!iter->Valid() ||
+                  options.comparator->Compare(iter->key(), "20000001") > 0);
+
+      iter->Seek("5000000000000fo8");
+      ASSERT_TRUE(!iter->Valid());
+
+      iter->Seek("1000000000000fo2");
+      ASSERT_TRUE(!iter->Valid());
+
+      iter->Seek("3000000000000fo2");
+      ASSERT_TRUE(!iter->Valid());
+
+      iter->Seek("8000000000000fo2");
+      ASSERT_TRUE(!iter->Valid());
+
+      delete iter;
+    }
+  }
+}
+
+TEST(PlainTableDBTest, HashBucketConflictReverseSuffixComparator) {
+  for (size_t huge_page_tlb_size = 0; huge_page_tlb_size <= 2 * 1024 * 1024;
+       huge_page_tlb_size += 2 * 1024 * 1024) {
+    for (unsigned char i = 1; i <= 3; i++) {
+      Options options = CurrentOptions();
+      options.create_if_missing = true;
+      SimpleSuffixReverseComparator comp;
+      options.comparator = &comp;
+      // Set only one bucket to force bucket conflict.
+      // Test index interval for the same prefix to be 1, 2 and 4
+      options.table_factory.reset(
+          NewPlainTableFactory(16, 0, 0, 2 ^ i, huge_page_tlb_size));
+      DestroyAndReopen(&options);
+      ASSERT_OK(Put("5000000000000fo0", "v1"));
+      ASSERT_OK(Put("5000000000000fo1", "v2"));
+      ASSERT_OK(Put("5000000000000fo2", "v"));
+      ASSERT_OK(Put("2000000000000fo0", "v3"));
+      ASSERT_OK(Put("2000000000000fo1", "v4"));
+      ASSERT_OK(Put("2000000000000fo2", "v"));
+      ASSERT_OK(Put("2000000000000fo3", "v"));
+
+      dbfull()->TEST_FlushMemTable();
+
+      ASSERT_EQ("v1", Get("5000000000000fo0"));
+      ASSERT_EQ("v2", Get("5000000000000fo1"));
+      ASSERT_EQ("v3", Get("2000000000000fo0"));
+      ASSERT_EQ("v4", Get("2000000000000fo1"));
+
+      ASSERT_EQ("NOT_FOUND", Get("5000000000000bar"));
+      ASSERT_EQ("NOT_FOUND", Get("2000000000000bar"));
+      ASSERT_EQ("NOT_FOUND", Get("5000000000000fo8"));
+      ASSERT_EQ("NOT_FOUND", Get("2000000000000fo8"));
+
+      ReadOptions ro;
+      Iterator* iter = dbfull()->NewIterator(ro);
+
+      iter->Seek("5000000000000fo1");
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("5000000000000fo1", iter->key().ToString());
+      iter->Next();
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("5000000000000fo0", iter->key().ToString());
+
+      iter->Seek("5000000000000fo1");
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("5000000000000fo1", iter->key().ToString());
+
+      iter->Seek("2000000000000fo1");
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("2000000000000fo1", iter->key().ToString());
+      iter->Next();
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("2000000000000fo0", iter->key().ToString());
+
+      iter->Seek("2000000000000fo1");
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("2000000000000fo1", iter->key().ToString());
+
+      iter->Seek("2000000000000var");
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("2000000000000fo3", iter->key().ToString());
+
+      iter->Seek("5000000000000var");
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_EQ("5000000000000fo2", iter->key().ToString());
+
+      std::string seek_key = "2000000000000bar";
+      iter->Seek(seek_key);
+      ASSERT_TRUE(!iter->Valid() ||
+                  options.prefix_extractor->Transform(iter->key()) !=
+                      options.prefix_extractor->Transform(seek_key));
+
+      iter->Seek("1000000000000fo2");
+      ASSERT_TRUE(!iter->Valid());
+
+      iter->Seek("3000000000000fo2");
+      ASSERT_TRUE(!iter->Valid());
+
+      iter->Seek("8000000000000fo2");
+      ASSERT_TRUE(!iter->Valid());
+
+      delete iter;
+    }
+  }
+}
+
+TEST(PlainTableDBTest, NonExistingKeyToNonEmptyBucket) {
+  Options options = CurrentOptions();
+  options.create_if_missing = true;
+  // Set only one bucket to force bucket conflict.
+  // Test index interval for the same prefix to be 1, 2 and 4
+  options.table_factory.reset(NewPlainTableFactory(16, 0, 0, 5));
+  DestroyAndReopen(&options);
+  ASSERT_OK(Put("5000000000000fo0", "v1"));
+  ASSERT_OK(Put("5000000000000fo1", "v2"));
+  ASSERT_OK(Put("5000000000000fo2", "v3"));
+
+  dbfull()->TEST_FlushMemTable();
+
+  ASSERT_EQ("v1", Get("5000000000000fo0"));
+  ASSERT_EQ("v2", Get("5000000000000fo1"));
+  ASSERT_EQ("v3", Get("5000000000000fo2"));
+
+  ASSERT_EQ("NOT_FOUND", Get("8000000000000bar"));
+  ASSERT_EQ("NOT_FOUND", Get("1000000000000bar"));
+
+  Iterator* iter = dbfull()->NewIterator(ReadOptions());
+
+  iter->Seek("5000000000000bar");
+  ASSERT_TRUE(iter->Valid());
+  ASSERT_EQ("5000000000000fo0", iter->key().ToString());
+
+  iter->Seek("5000000000000fo8");
+  ASSERT_TRUE(!iter->Valid());
+
+  iter->Seek("1000000000000fo2");
+  ASSERT_TRUE(!iter->Valid());
+
+  iter->Seek("8000000000000fo2");
+  ASSERT_TRUE(!iter->Valid());
+
+  delete iter;
+}
+
+static std::string Key(int i) {
+  char buf[100];
+  snprintf(buf, sizeof(buf), "key_______%06d", i);
+  return std::string(buf);
+}
+
+static std::string RandomString(Random* rnd, int len) {
+  std::string r;
+  test::RandomString(rnd, len, &r);
+  return r;
+}
+
+TEST(PlainTableDBTest, CompactionTrigger) {
+  Options options = CurrentOptions();
+  options.write_buffer_size = 100 << 10; //100KB
+  options.num_levels = 3;
+  options.max_mem_compaction_level = 0;
+  options.level0_file_num_compaction_trigger = 3;
+  Reopen(&options);
+
+  Random rnd(301);
+
+  for (int num = 0; num < options.level0_file_num_compaction_trigger - 1;
+      num++) {
+    std::vector<std::string> values;
+    // Write 120KB (12 values, each 10K)
+    for (int i = 0; i < 12; i++) {
+      values.push_back(RandomString(&rnd, 10000));
+      ASSERT_OK(Put(Key(i), values[i]));
+    }
+    dbfull()->TEST_WaitForFlushMemTable();
+    ASSERT_EQ(NumTableFilesAtLevel(0), num + 1);
+  }
+
+  //generate one more file in level-0, and should trigger level-0 compaction
+  std::vector<std::string> values;
+  for (int i = 0; i < 12; i++) {
+    values.push_back(RandomString(&rnd, 10000));
+    ASSERT_OK(Put(Key(i), values[i]));
+  }
+  dbfull()->TEST_WaitForCompact();
+
+  ASSERT_EQ(NumTableFilesAtLevel(0), 0);
+  ASSERT_EQ(NumTableFilesAtLevel(1), 1);
+}
+
+TEST(PlainTableDBTest, AdaptiveTable) {
+  Options options = CurrentOptions();
+  options.create_if_missing = true;
+
+  options.table_factory.reset(NewPlainTableFactory());
+  DestroyAndReopen(&options);
+
+  ASSERT_OK(Put("1000000000000foo", "v1"));
+  ASSERT_OK(Put("0000000000000bar", "v2"));
+  ASSERT_OK(Put("1000000000000foo", "v3"));
+  dbfull()->TEST_FlushMemTable();
+
+  options.create_if_missing = false;
+  std::shared_ptr<TableFactory> dummy_factory;
+  std::shared_ptr<TableFactory> block_based_factory(
+      NewBlockBasedTableFactory());
+  options.table_factory.reset(NewAdaptiveTableFactory(
+      block_based_factory, dummy_factory, dummy_factory));
+  Reopen(&options);
+  ASSERT_EQ("v3", Get("1000000000000foo"));
+  ASSERT_EQ("v2", Get("0000000000000bar"));
+
+  ASSERT_OK(Put("2000000000000foo", "v4"));
+  ASSERT_OK(Put("3000000000000bar", "v5"));
+  dbfull()->TEST_FlushMemTable();
+  ASSERT_EQ("v4", Get("2000000000000foo"));
+  ASSERT_EQ("v5", Get("3000000000000bar"));
+
+  Reopen(&options);
+  ASSERT_EQ("v3", Get("1000000000000foo"));
+  ASSERT_EQ("v2", Get("0000000000000bar"));
+  ASSERT_EQ("v4", Get("2000000000000foo"));
+  ASSERT_EQ("v5", Get("3000000000000bar"));
+
+  options.table_factory.reset(NewBlockBasedTableFactory());
+  Reopen(&options);
+  ASSERT_NE("v3", Get("1000000000000foo"));
+
+  options.table_factory.reset(NewPlainTableFactory());
+  Reopen(&options);
+  ASSERT_NE("v5", Get("3000000000000bar"));
+}
+
+}  // namespace rocksdb
+
+int main(int argc, char** argv) {
+  return rocksdb::test::RunAllTests();
+}

db/prefix_filter_iterator.h

@@ -1,76 +0,0 @@
-// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file. See the AUTHORS file for names of contributors.
-//
-// Wrap an underlying iterator, but exclude any results not starting
-// with a given prefix.  Seeking to keys not beginning with the prefix
-// is invalid, and SeekToLast is not implemented (that would be
-// non-trivial), but otherwise this iterator will behave just like the
-// underlying iterator would if there happened to be no non-matching
-// keys in the dataset.
-
-#ifndef STORAGE_LEVELDB_DB_PREFIX_FILTER_ITERATOR_H_
-#define STORAGE_LEVELDB_DB_PREFIX_FILTER_ITERATOR_H_
-
-#include "rocksdb/iterator.h"
-
-namespace rocksdb {
-
-class PrefixFilterIterator : public Iterator {
- private:
-  Iterator* iter_;
-  const Slice &prefix_;
-  const SliceTransform *prefix_extractor_;
-  Status status_;
-
- public:
-  PrefixFilterIterator(Iterator* iter,
-                       const Slice &prefix,
-                       const SliceTransform* prefix_extractor)
-                             : iter_(iter), prefix_(prefix),
-                               prefix_extractor_(prefix_extractor),
-                               status_(Status::OK()) {
-    if (prefix_extractor == nullptr) {
-      status_ = Status::InvalidArgument("A prefix filter may not be used "
-                                        "unless a function is also defined "
-                                        "for extracting prefixes");
-    } else if (!prefix_extractor_->InRange(prefix)) {
-      status_ = Status::InvalidArgument("Must provide a slice for prefix which"
-                                        "is a prefix for some key");
-    }
-  }
-  ~PrefixFilterIterator() {
-    delete iter_;
-  }
-  Slice key() const { return iter_->key(); }
-  Slice value() const { return iter_->value(); }
-  Status status() const {
-    if (!status_.ok()) {
-      return status_;
-    }
-    return iter_->status();
-  }
-  void Next() { iter_->Next(); }
-  void Prev() { iter_->Prev(); }
-  void Seek(const Slice& k) {
-    if (prefix_extractor_->Transform(k) == prefix_) {
-      iter_->Seek(k);
-    } else {
-      status_ = Status::InvalidArgument("Seek must begin with target prefix");
-    }
-  }
-  void SeekToFirst() {
-    Seek(prefix_);
-  }
-  void SeekToLast() {
-    status_ = Status::NotSupported("SeekToLast is incompatible with prefixes");
-  }
-  bool Valid() const {
-    return (status_.ok() && iter_->Valid() &&
-            prefix_extractor_->Transform(iter_->key()) == prefix_);
-  }
-};
-
-}  // namespace rocksdb
-
-#endif

db/prefix_test.cc

@@ -0,0 +1,504 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+
+#ifndef GFLAGS
+#include <cstdio>
+int main() {
+  fprintf(stderr, "Please install gflags to run rocksdb tools\n");
+  return 1;
+}
+#else
+
+#include <algorithm>
+#include <iostream>
+#include <vector>
+
+#include <gflags/gflags.h>
+#include "rocksdb/comparator.h"
+#include "rocksdb/db.h"
+#include "rocksdb/perf_context.h"
+#include "rocksdb/slice_transform.h"
+#include "rocksdb/memtablerep.h"
+#include "util/histogram.h"
+#include "util/stop_watch.h"
+#include "util/testharness.h"
+
+using GFLAGS::ParseCommandLineFlags;
+
+DEFINE_bool(trigger_deadlock, false,
+            "issue delete in range scan to trigger PrefixHashMap deadlock");
+DEFINE_uint64(bucket_count, 100000, "number of buckets");
+DEFINE_uint64(num_locks, 10001, "number of locks");
+DEFINE_bool(random_prefix, false, "randomize prefix");
+DEFINE_uint64(total_prefixes, 100000, "total number of prefixes");
+DEFINE_uint64(items_per_prefix, 1, "total number of values per prefix");
+DEFINE_int64(write_buffer_size, 33554432, "");
+DEFINE_int64(max_write_buffer_number, 2, "");
+DEFINE_int64(min_write_buffer_number_to_merge, 1, "");
+DEFINE_int32(skiplist_height, 4, "");
+DEFINE_int32(memtable_prefix_bloom_bits, 10000000, "");
+DEFINE_int32(memtable_prefix_bloom_probes, 10, "");
+DEFINE_int32(memtable_prefix_bloom_huge_page_tlb_size, 2 * 1024 * 1024, "");
+DEFINE_int32(value_size, 40, "");
+
+// Path to the database on file system
+const std::string kDbName = rocksdb::test::TmpDir() + "/prefix_test";
+
+namespace rocksdb {
+
+struct TestKey {
+  uint64_t prefix;
+  uint64_t sorted;
+
+  TestKey(uint64_t prefix, uint64_t sorted) : prefix(prefix), sorted(sorted) {}
+};
+
+// return a slice backed by test_key
+inline Slice TestKeyToSlice(const TestKey& test_key) {
+  return Slice((const char*)&test_key, sizeof(test_key));
+}
+
+inline const TestKey* SliceToTestKey(const Slice& slice) {
+  return (const TestKey*)slice.data();
+}
+
+class TestKeyComparator : public Comparator {
+ public:
+
+  // Compare needs to be aware of the possibility of a and/or b is
+  // prefix only
+  virtual int Compare(const Slice& a, const Slice& b) const {
+    const TestKey* key_a = SliceToTestKey(a);
+    const TestKey* key_b = SliceToTestKey(b);
+    if (key_a->prefix != key_b->prefix) {
+      if (key_a->prefix < key_b->prefix) return -1;
+      if (key_a->prefix > key_b->prefix) return 1;
+    } else {
+      ASSERT_TRUE(key_a->prefix == key_b->prefix);
+      // note, both a and b could be prefix only
+      if (a.size() != b.size()) {
+        // one of them is prefix
+        ASSERT_TRUE(
+          (a.size() == sizeof(uint64_t) && b.size() == sizeof(TestKey)) ||
+          (b.size() == sizeof(uint64_t) && a.size() == sizeof(TestKey)));
+        if (a.size() < b.size()) return -1;
+        if (a.size() > b.size()) return 1;
+      } else {
+        // both a and b are prefix
+        if (a.size() == sizeof(uint64_t)) {
+          return 0;
+        }
+
+        // both a and b are whole key
+        ASSERT_TRUE(a.size() == sizeof(TestKey) && b.size() == sizeof(TestKey));
+        if (key_a->sorted < key_b->sorted) return -1;
+        if (key_a->sorted > key_b->sorted) return 1;
+        if (key_a->sorted == key_b->sorted) return 0;
+      }
+    }
+    return 0;
+  }
+
+  virtual const char* Name() const override {
+    return "TestKeyComparator";
+  }
+
+  virtual void FindShortestSeparator(
+      std::string* start,
+      const Slice& limit) const {
+  }
+
+  virtual void FindShortSuccessor(std::string* key) const {}
+
+};
+
+namespace {
+void PutKey(DB* db, WriteOptions write_options, uint64_t prefix,
+            uint64_t suffix, const Slice& value) {
+  TestKey test_key(prefix, suffix);
+  Slice key = TestKeyToSlice(test_key);
+  ASSERT_OK(db->Put(write_options, key, value));
+}
+
+void SeekIterator(Iterator* iter, uint64_t prefix, uint64_t suffix) {
+  TestKey test_key(prefix, suffix);
+  Slice key = TestKeyToSlice(test_key);
+  iter->Seek(key);
+}
+
+const std::string kNotFoundResult = "NOT_FOUND";
+
+std::string Get(DB* db, const ReadOptions& read_options, uint64_t prefix,
+                uint64_t suffix) {
+  TestKey test_key(prefix, suffix);
+  Slice key = TestKeyToSlice(test_key);
+
+  std::string result;
+  Status s = db->Get(read_options, key, &result);
+  if (s.IsNotFound()) {
+    result = kNotFoundResult;
+  } else if (!s.ok()) {
+    result = s.ToString();
+  }
+  return result;
+}
+}  // namespace
+
+class PrefixTest {
+ public:
+  std::shared_ptr<DB> OpenDb() {
+    DB* db;
+
+    options.create_if_missing = true;
+    options.write_buffer_size = FLAGS_write_buffer_size;
+    options.max_write_buffer_number = FLAGS_max_write_buffer_number;
+    options.min_write_buffer_number_to_merge =
+      FLAGS_min_write_buffer_number_to_merge;
+
+    options.memtable_prefix_bloom_bits = FLAGS_memtable_prefix_bloom_bits;
+    options.memtable_prefix_bloom_probes = FLAGS_memtable_prefix_bloom_probes;
+    options.memtable_prefix_bloom_huge_page_tlb_size =
+        FLAGS_memtable_prefix_bloom_huge_page_tlb_size;
+
+    Status s = DB::Open(options, kDbName,  &db);
+    ASSERT_OK(s);
+    return std::shared_ptr<DB>(db);
+  }
+
+  void FirstOption() {
+    option_config_ = kBegin;
+  }
+
+  bool NextOptions(int bucket_count) {
+    // skip some options
+    option_config_++;
+    if (option_config_ < kEnd) {
+      options.prefix_extractor.reset(NewFixedPrefixTransform(8));
+      switch(option_config_) {
+        case kHashSkipList:
+          options.memtable_factory.reset(
+              NewHashSkipListRepFactory(bucket_count, FLAGS_skiplist_height));
+          return true;
+        case kHashLinkList:
+          options.memtable_factory.reset(
+              NewHashLinkListRepFactory(bucket_count));
+          return true;
+        case kHashLinkListHugePageTlb:
+          options.memtable_factory.reset(
+              NewHashLinkListRepFactory(bucket_count, 2 * 1024 * 1024));
+          return true;
+        case kHashLinkListTriggerSkipList:
+          options.memtable_factory.reset(
+              NewHashLinkListRepFactory(bucket_count, 0, 3));
+          return true;
+        default:
+          return false;
+      }
+    }
+    return false;
+  }
+
+  PrefixTest() : option_config_(kBegin) {
+    options.comparator = new TestKeyComparator();
+  }
+  ~PrefixTest() {
+    delete options.comparator;
+  }
+ protected:
+  enum OptionConfig {
+    kBegin,
+    kHashSkipList,
+    kHashLinkList,
+    kHashLinkListHugePageTlb,
+    kHashLinkListTriggerSkipList,
+    kEnd
+  };
+  int option_config_;
+  Options options;
+};
+
+TEST(PrefixTest, TestResult) {
+  for (int num_buckets = 1; num_buckets <= 2; num_buckets++) {
+    FirstOption();
+    while (NextOptions(num_buckets)) {
+      std::cout << "*** Mem table: " << options.memtable_factory->Name()
+                << " number of buckets: " << num_buckets
+                << std::endl;
+      DestroyDB(kDbName, Options());
+      auto db = OpenDb();
+      WriteOptions write_options;
+      ReadOptions read_options;
+
+      // 1. Insert one row.
+      Slice v16("v16");
+      PutKey(db.get(), write_options, 1, 6, v16);
+      std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
+      SeekIterator(iter.get(), 1, 6);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v16 == iter->value());
+      SeekIterator(iter.get(), 1, 5);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v16 == iter->value());
+      SeekIterator(iter.get(), 1, 5);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v16 == iter->value());
+      iter->Next();
+      ASSERT_TRUE(!iter->Valid());
+
+      SeekIterator(iter.get(), 2, 0);
+      ASSERT_TRUE(!iter->Valid());
+
+      ASSERT_EQ(v16.ToString(), Get(db.get(), read_options, 1, 6));
+      ASSERT_EQ(kNotFoundResult, Get(db.get(), read_options, 1, 5));
+      ASSERT_EQ(kNotFoundResult, Get(db.get(), read_options, 1, 7));
+      ASSERT_EQ(kNotFoundResult, Get(db.get(), read_options, 0, 6));
+      ASSERT_EQ(kNotFoundResult, Get(db.get(), read_options, 2, 6));
+
+      // 2. Insert an entry for the same prefix as the last entry in the bucket.
+      Slice v17("v17");
+      PutKey(db.get(), write_options, 1, 7, v17);
+      iter.reset(db->NewIterator(read_options));
+      SeekIterator(iter.get(), 1, 7);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v17 == iter->value());
+
+      SeekIterator(iter.get(), 1, 6);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v16 == iter->value());
+      iter->Next();
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v17 == iter->value());
+      iter->Next();
+      ASSERT_TRUE(!iter->Valid());
+
+      SeekIterator(iter.get(), 2, 0);
+      ASSERT_TRUE(!iter->Valid());
+
+      // 3. Insert an entry for the same prefix as the head of the bucket.
+      Slice v15("v15");
+      PutKey(db.get(), write_options, 1, 5, v15);
+      iter.reset(db->NewIterator(read_options));
+
+      SeekIterator(iter.get(), 1, 7);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v17 == iter->value());
+
+      SeekIterator(iter.get(), 1, 5);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v15 == iter->value());
+      iter->Next();
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v16 == iter->value());
+      iter->Next();
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v17 == iter->value());
+
+      SeekIterator(iter.get(), 1, 5);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v15 == iter->value());
+
+      ASSERT_EQ(v15.ToString(), Get(db.get(), read_options, 1, 5));
+      ASSERT_EQ(v16.ToString(), Get(db.get(), read_options, 1, 6));
+      ASSERT_EQ(v17.ToString(), Get(db.get(), read_options, 1, 7));
+
+      // 4. Insert an entry with a larger prefix
+      Slice v22("v22");
+      PutKey(db.get(), write_options, 2, 2, v22);
+      iter.reset(db->NewIterator(read_options));
+
+      SeekIterator(iter.get(), 2, 2);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v22 == iter->value());
+      SeekIterator(iter.get(), 2, 0);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v22 == iter->value());
+
+      SeekIterator(iter.get(), 1, 5);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v15 == iter->value());
+
+      SeekIterator(iter.get(), 1, 7);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v17 == iter->value());
+
+      // 5. Insert an entry with a smaller prefix
+      Slice v02("v02");
+      PutKey(db.get(), write_options, 0, 2, v02);
+      iter.reset(db->NewIterator(read_options));
+
+      SeekIterator(iter.get(), 0, 2);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v02 == iter->value());
+      SeekIterator(iter.get(), 0, 0);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v02 == iter->value());
+
+      SeekIterator(iter.get(), 2, 0);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v22 == iter->value());
+
+      SeekIterator(iter.get(), 1, 5);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v15 == iter->value());
+
+      SeekIterator(iter.get(), 1, 7);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v17 == iter->value());
+
+      // 6. Insert to the beginning and the end of the first prefix
+      Slice v13("v13");
+      Slice v18("v18");
+      PutKey(db.get(), write_options, 1, 3, v13);
+      PutKey(db.get(), write_options, 1, 8, v18);
+      iter.reset(db->NewIterator(read_options));
+      SeekIterator(iter.get(), 1, 7);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v17 == iter->value());
+
+      SeekIterator(iter.get(), 1, 3);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v13 == iter->value());
+      iter->Next();
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v15 == iter->value());
+      iter->Next();
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v16 == iter->value());
+      iter->Next();
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v17 == iter->value());
+      iter->Next();
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v18 == iter->value());
+
+      SeekIterator(iter.get(), 0, 0);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v02 == iter->value());
+
+      SeekIterator(iter.get(), 2, 0);
+      ASSERT_TRUE(iter->Valid());
+      ASSERT_TRUE(v22 == iter->value());
+
+      ASSERT_EQ(v22.ToString(), Get(db.get(), read_options, 2, 2));
+      ASSERT_EQ(v02.ToString(), Get(db.get(), read_options, 0, 2));
+      ASSERT_EQ(v13.ToString(), Get(db.get(), read_options, 1, 3));
+      ASSERT_EQ(v15.ToString(), Get(db.get(), read_options, 1, 5));
+      ASSERT_EQ(v16.ToString(), Get(db.get(), read_options, 1, 6));
+      ASSERT_EQ(v17.ToString(), Get(db.get(), read_options, 1, 7));
+      ASSERT_EQ(v18.ToString(), Get(db.get(), read_options, 1, 8));
+    }
+  }
+}
+
+TEST(PrefixTest, DynamicPrefixIterator) {
+  while (NextOptions(FLAGS_bucket_count)) {
+    std::cout << "*** Mem table: " << options.memtable_factory->Name()
+        << std::endl;
+    DestroyDB(kDbName, Options());
+    auto db = OpenDb();
+    WriteOptions write_options;
+    ReadOptions read_options;
+
+    std::vector<uint64_t> prefixes;
+    for (uint64_t i = 0; i < FLAGS_total_prefixes; ++i) {
+      prefixes.push_back(i);
+    }
+
+    if (FLAGS_random_prefix) {
+      std::random_shuffle(prefixes.begin(), prefixes.end());
+    }
+
+    HistogramImpl hist_put_time;
+    HistogramImpl hist_put_comparison;
+
+    // insert x random prefix, each with y continuous element.
+    for (auto prefix : prefixes) {
+       for (uint64_t sorted = 0; sorted < FLAGS_items_per_prefix; sorted++) {
+        TestKey test_key(prefix, sorted);
+
+        Slice key = TestKeyToSlice(test_key);
+        std::string value(FLAGS_value_size, 0);
+
+        perf_context.Reset();
+        StopWatchNano timer(Env::Default(), true);
+        ASSERT_OK(db->Put(write_options, key, value));
+        hist_put_time.Add(timer.ElapsedNanos());
+        hist_put_comparison.Add(perf_context.user_key_comparison_count);
+      }
+    }
+
+    std::cout << "Put key comparison: \n" << hist_put_comparison.ToString()
+              << "Put time: \n" << hist_put_time.ToString();
+
+    // test seek existing keys
+    HistogramImpl hist_seek_time;
+    HistogramImpl hist_seek_comparison;
+
+    std::unique_ptr<Iterator> iter(db->NewIterator(read_options));
+
+    for (auto prefix : prefixes) {
+      TestKey test_key(prefix, FLAGS_items_per_prefix / 2);
+      Slice key = TestKeyToSlice(test_key);
+      std::string value = "v" + std::to_string(0);
+
+      perf_context.Reset();
+      StopWatchNano timer(Env::Default(), true);
+      auto key_prefix = options.prefix_extractor->Transform(key);
+      uint64_t total_keys = 0;
+      for (iter->Seek(key);
+           iter->Valid() && iter->key().starts_with(key_prefix);
+           iter->Next()) {
+        if (FLAGS_trigger_deadlock) {
+          std::cout << "Behold the deadlock!\n";
+          db->Delete(write_options, iter->key());
+        }
+        total_keys++;
+      }
+      hist_seek_time.Add(timer.ElapsedNanos());
+      hist_seek_comparison.Add(perf_context.user_key_comparison_count);
+      ASSERT_EQ(total_keys, FLAGS_items_per_prefix - FLAGS_items_per_prefix/2);
+    }
+
+    std::cout << "Seek key comparison: \n"
+              << hist_seek_comparison.ToString()
+              << "Seek time: \n"
+              << hist_seek_time.ToString();
+
+    // test non-existing keys
+    HistogramImpl hist_no_seek_time;
+    HistogramImpl hist_no_seek_comparison;
+
+    for (auto prefix = FLAGS_total_prefixes;
+         prefix < FLAGS_total_prefixes + 10000;
+         prefix++) {
+      TestKey test_key(prefix, 0);
+      Slice key = TestKeyToSlice(test_key);
+
+      perf_context.Reset();
+      StopWatchNano timer(Env::Default(), true);
+      iter->Seek(key);
+      hist_no_seek_time.Add(timer.ElapsedNanos());
+      hist_no_seek_comparison.Add(perf_context.user_key_comparison_count);
+      ASSERT_TRUE(!iter->Valid());
+    }
+
+    std::cout << "non-existing Seek key comparison: \n"
+              << hist_no_seek_comparison.ToString()
+              << "non-existing Seek time: \n"
+              << hist_no_seek_time.ToString();
+  }
+}
+
+}
+
+int main(int argc, char** argv) {
+  ParseCommandLineFlags(&argc, &argv, true);
+  std::cout << kDbName << "\n";
+
+  rocksdb::test::RunAllTests();
+  return 0;
+}
+
+#endif  // GFLAGS

db/repair.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -24,6 +29,10 @@
 //   Store per-table metadata (smallest, largest, largest-seq#, ...)
 //   in the table's meta section to speed up ScanTable.
 
+#ifndef ROCKSDB_LITE
+
+#define __STDC_FORMAT_MACROS
+#include <inttypes.h>
 #include "db/builder.h"
 #include "db/db_impl.h"
 #include "db/dbformat.h"
@@ -50,14 +59,20 @@ class Repairer {
         icmp_(options.comparator),
         ipolicy_(options.filter_policy),
         options_(SanitizeOptions(dbname, &icmp_, &ipolicy_, options)),
+        raw_table_cache_(
+            // TableCache can be small since we expect each table to be opened
+            // once.
+            NewLRUCache(10, options_.table_cache_numshardbits,
+                        options_.table_cache_remove_scan_count_limit)),
         next_file_number_(1) {
-    // TableCache can be small since we expect each table to be opened once.
-    table_cache_ = new TableCache(dbname_, &options_, storage_options_, 10);
-    edit_ = new VersionEdit(options.num_levels);
+    table_cache_ =
+        new TableCache(&options_, storage_options_, raw_table_cache_.get());
+    edit_ = new VersionEdit();
   }
 
   ~Repairer() {
     delete table_cache_;
+    raw_table_cache_.reset();
     delete edit_;
   }
 
@@ -69,18 +84,17 @@ class Repairer {
       status = WriteDescriptor();
     }
     if (status.ok()) {
-      unsigned long long bytes = 0;
+      uint64_t bytes = 0;
       for (size_t i = 0; i < tables_.size(); i++) {
-        bytes += tables_[i].meta.file_size;
+        bytes += tables_[i].meta.fd.GetFileSize();
       }
       Log(options_.info_log,
-          "**** Repaired leveldb %s; "
-          "recovered %d files; %llu bytes. "
+          "**** Repaired rocksdb %s; "
+          "recovered %zu files; %" PRIu64
+          "bytes. "
           "Some data may have been lost. "
           "****",
-          dbname_.c_str(),
-          static_cast<int>(tables_.size()),
-          bytes);
+          dbname_.c_str(), tables_.size(), bytes);
     }
     return status;
   }
@@ -97,12 +111,12 @@ class Repairer {
   InternalKeyComparator const icmp_;
   InternalFilterPolicy const ipolicy_;
   Options const options_;
-  bool owns_cache_;
+  std::shared_ptr<Cache> raw_table_cache_;
   TableCache* table_cache_;
   VersionEdit* edit_;
 
   std::vector<std::string> manifests_;
-  std::vector<uint64_t> table_numbers_;
+  std::vector<FileDescriptor> table_fds_;
   std::vector<uint64_t> logs_;
   std::vector<TableInfo> tables_;
   uint64_t next_file_number_;
@@ -110,35 +124,43 @@ class Repairer {
 
   Status FindFiles() {
     std::vector<std::string> filenames;
-    Status status = env_->GetChildren(dbname_, &filenames);
-    if (!status.ok()) {
-      return status;
-    }
-    if (filenames.empty()) {
-      return Status::IOError(dbname_, "repair found no files");
-    }
+    bool found_file = false;
+    for (uint32_t path_id = 0; path_id < options_.db_paths.size(); path_id++) {
+      Status status = env_->GetChildren(options_.db_paths[path_id], &filenames);
+      if (!status.ok()) {
+        return status;
+      }
+      if (!filenames.empty()) {
+        found_file = true;
+      }
 
-    uint64_t number;
-    FileType type;
-    for (size_t i = 0; i < filenames.size(); i++) {
-      if (ParseFileName(filenames[i], &number, &type)) {
-        if (type == kDescriptorFile) {
-          manifests_.push_back(filenames[i]);
-        } else {
-          if (number + 1 > next_file_number_) {
-            next_file_number_ = number + 1;
-          }
-          if (type == kLogFile) {
-            logs_.push_back(number);
-          } else if (type == kTableFile) {
-            table_numbers_.push_back(number);
+      uint64_t number;
+      FileType type;
+      for (size_t i = 0; i < filenames.size(); i++) {
+        if (ParseFileName(filenames[i], &number, &type)) {
+          if (type == kDescriptorFile) {
+            assert(path_id == 0);
+            manifests_.push_back(filenames[i]);
           } else {
-            // Ignore other files
+            if (number + 1 > next_file_number_) {
+              next_file_number_ = number + 1;
+            }
+            if (type == kLogFile) {
+              assert(path_id == 0);
+              logs_.push_back(number);
+            } else if (type == kTableFile) {
+              table_fds_.emplace_back(number, path_id, 0);
+            } else {
+              // Ignore other files
+            }
           }
         }
       }
     }
-    return status;
+    if (!found_file) {
+      return Status::Corruption(dbname_, "repair found no files");
+    }
+    return Status::OK();
   }
 
   void ConvertLogFilesToTables() {
@@ -146,8 +168,8 @@ class Repairer {
       std::string logname = LogFileName(dbname_, logs_[i]);
       Status status = ConvertLogToTable(logs_[i]);
       if (!status.ok()) {
-        Log(options_.info_log, "Log #%llu: ignoring conversion error: %s",
-            (unsigned long long) logs_[i],
+        Log(options_.info_log,
+            "Log #%" PRIu64 ": ignoring conversion error: %s", logs_[i],
             status.ToString().c_str());
       }
       ArchiveFile(logname);
@@ -161,10 +183,8 @@ class Repairer {
       uint64_t lognum;
       virtual void Corruption(size_t bytes, const Status& s) {
         // We print error messages for corruption, but continue repairing.
-        Log(info_log, "Log #%llu: dropping %d bytes; %s",
-            (unsigned long long) lognum,
-            static_cast<int>(bytes),
-            s.ToString().c_str());
+        Log(info_log, "Log #%" PRIu64 ": dropping %d bytes; %s", lognum,
+            static_cast<int>(bytes), s.ToString().c_str());
       }
     };
 
@@ -192,8 +212,8 @@ class Repairer {
     std::string scratch;
     Slice record;
     WriteBatch batch;
-    MemTable* mem = new MemTable(icmp_, options_.memtable_factory,
-      options_.num_levels);
+    MemTable* mem = new MemTable(icmp_, options_);
+    auto cf_mems_default = new ColumnFamilyMemTablesDefault(mem, &options_);
     mem->Ref();
     int counter = 0;
     while (reader.ReadRecord(&record, &scratch)) {
@@ -203,12 +223,11 @@ class Repairer {
         continue;
       }
       WriteBatchInternal::SetContents(&batch, record);
-      status = WriteBatchInternal::InsertInto(&batch, mem);
+      status = WriteBatchInternal::InsertInto(&batch, cf_mems_default);
       if (status.ok()) {
         counter += WriteBatchInternal::Count(&batch);
       } else {
-        Log(options_.info_log, "Log #%llu: ignoring %s",
-            (unsigned long long) log,
+        Log(options_.info_log, "Log #%" PRIu64 ": ignoring %s", log,
             status.ToString().c_str());
         status = Status::OK();  // Keep going with rest of file
       }
@@ -217,37 +236,37 @@ class Repairer {
     // Do not record a version edit for this conversion to a Table
     // since ExtractMetaData() will also generate edits.
     FileMetaData meta;
-    meta.number = next_file_number_++;
-    Iterator* iter = mem->NewIterator();
-    status = BuildTable(dbname_, env_, options_, storage_options_,
-                        table_cache_, iter, &meta,
-                        icmp_.user_comparator(), 0, 0);
+    meta.fd = FileDescriptor(next_file_number_++, 0, 0);
+    ReadOptions ro;
+    Iterator* iter = mem->NewIterator(ro, true /* enforce_total_order */);
+    status = BuildTable(dbname_, env_, options_, storage_options_, table_cache_,
+                        iter, &meta, icmp_, 0, 0, kNoCompression);
     delete iter;
-    mem->Unref();
+    delete mem->Unref();
+    delete cf_mems_default;
     mem = nullptr;
     if (status.ok()) {
-      if (meta.file_size > 0) {
-        table_numbers_.push_back(meta.number);
+      if (meta.fd.GetFileSize() > 0) {
+        table_fds_.push_back(meta.fd);
       }
     }
-    Log(options_.info_log, "Log #%llu: %d ops saved to Table #%llu %s",
-        (unsigned long long) log,
-        counter,
-        (unsigned long long) meta.number,
-        status.ToString().c_str());
+    Log(options_.info_log,
+        "Log #%" PRIu64 ": %d ops saved to Table #%" PRIu64 " %s", log, counter,
+        meta.fd.GetNumber(), status.ToString().c_str());
     return status;
   }
 
   void ExtractMetaData() {
-    std::vector<TableInfo> kept;
-    for (size_t i = 0; i < table_numbers_.size(); i++) {
+    for (size_t i = 0; i < table_fds_.size(); i++) {
       TableInfo t;
-      t.meta.number = table_numbers_[i];
+      t.meta.fd = table_fds_[i];
       Status status = ScanTable(&t);
       if (!status.ok()) {
-        std::string fname = TableFileName(dbname_, table_numbers_[i]);
-        Log(options_.info_log, "Table #%llu: ignoring %s",
-            (unsigned long long) table_numbers_[i],
+        std::string fname = TableFileName(
+            options_.db_paths, t.meta.fd.GetNumber(), t.meta.fd.GetPathId());
+        Log(options_.info_log, "Table #%s: ignoring %s",
+            FormatFileNumber(t.meta.fd.GetNumber(), t.meta.fd.GetPathId())
+                .c_str(),
             status.ToString().c_str());
         ArchiveFile(fname);
       } else {
@@ -257,12 +276,16 @@ class Repairer {
   }
 
   Status ScanTable(TableInfo* t) {
-    std::string fname = TableFileName(dbname_, t->meta.number);
+    std::string fname = TableFileName(options_.db_paths, t->meta.fd.GetNumber(),
+                                      t->meta.fd.GetPathId());
     int counter = 0;
-    Status status = env_->GetFileSize(fname, &t->meta.file_size);
+    uint64_t file_size;
+    Status status = env_->GetFileSize(fname, &file_size);
+    t->meta.fd = FileDescriptor(t->meta.fd.GetNumber(), t->meta.fd.GetPathId(),
+                                file_size);
     if (status.ok()) {
       Iterator* iter = table_cache_->NewIterator(
-          ReadOptions(), storage_options_, t->meta.number, t->meta.file_size);
+          ReadOptions(), storage_options_, icmp_, t->meta.fd);
       bool empty = true;
       ParsedInternalKey parsed;
       t->min_sequence = 0;
@@ -270,9 +293,8 @@ class Repairer {
       for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
         Slice key = iter->key();
         if (!ParseInternalKey(key, &parsed)) {
-          Log(options_.info_log, "Table #%llu: unparsable key %s",
-              (unsigned long long) t->meta.number,
-              EscapeString(key).c_str());
+          Log(options_.info_log, "Table #%" PRIu64 ": unparsable key %s",
+              t->meta.fd.GetNumber(), EscapeString(key).c_str());
           continue;
         }
 
@@ -294,17 +316,16 @@ class Repairer {
       }
       delete iter;
     }
-    Log(options_.info_log, "Table #%llu: %d entries %s",
-        (unsigned long long) t->meta.number,
-        counter,
-        status.ToString().c_str());
+    Log(options_.info_log, "Table #%" PRIu64 ": %d entries %s",
+        t->meta.fd.GetNumber(), counter, status.ToString().c_str());
     return status;
   }
 
   Status WriteDescriptor() {
     std::string tmp = TempFileName(dbname_, 1);
     unique_ptr<WritableFile> file;
-    Status status = env_->NewWritableFile(tmp, &file, storage_options_);
+    Status status = env_->NewWritableFile(
+        tmp, &file, env_->OptimizeForManifestWrite(storage_options_));
     if (!status.ok()) {
       return status;
     }
@@ -324,9 +345,9 @@ class Repairer {
     for (size_t i = 0; i < tables_.size(); i++) {
       // TODO(opt): separate out into multiple levels
       const TableInfo& t = tables_[i];
-      edit_->AddFile(0, t.meta.number, t.meta.file_size,
-                    t.meta.smallest, t.meta.largest,
-                    t.min_sequence, t.max_sequence);
+      edit_->AddFile(0, t.meta.fd.GetNumber(), t.meta.fd.GetPathId(),
+                     t.meta.fd.GetFileSize(), t.meta.smallest, t.meta.largest,
+                     t.min_sequence, t.max_sequence);
     }
 
     //fprintf(stderr, "NewDescriptor:\n%s\n", edit_.DebugString().c_str());
@@ -348,7 +369,7 @@ class Repairer {
       // Install new manifest
       status = env_->RenameFile(tmp, DescriptorFileName(dbname_, 1));
       if (status.ok()) {
-        status = SetCurrentFile(env_, dbname_, 1);
+        status = SetCurrentFile(env_, dbname_, 1, nullptr);
       } else {
         env_->DeleteFile(tmp);
       }
@@ -384,3 +405,5 @@ Status RepairDB(const std::string& dbname, const Options& options) {
 }
 
 }  // namespace rocksdb
+
+#endif  // ROCKSDB_LITE

db/simple_table_db_test.cc

@@ -0,0 +1,800 @@
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+#include <algorithm>
+#include <set>
+
+#include "rocksdb/db.h"
+#include "rocksdb/filter_policy.h"
+#include "db/db_impl.h"
+#include "db/filename.h"
+#include "db/version_set.h"
+#include "db/write_batch_internal.h"
+#include "rocksdb/statistics.h"
+#include "rocksdb/cache.h"
+#include "rocksdb/compaction_filter.h"
+#include "rocksdb/env.h"
+#include "rocksdb/table.h"
+#include "rocksdb/table_properties.h"
+#include "table/table_builder.h"
+#include "util/hash.h"
+#include "util/logging.h"
+#include "util/mutexlock.h"
+#include "util/testharness.h"
+#include "util/testutil.h"
+#include "utilities/merge_operators.h"
+
+using std::unique_ptr;
+
+// IS THIS FILE STILL NEEDED?
+namespace rocksdb {
+
+// SimpleTable is a simple table format for UNIT TEST ONLY. It is not built
+// as production quality.
+// SimpleTable requires the input key size to be fixed 16 bytes, value cannot
+// be longer than 150000 bytes and stored data on disk in this format:
+// +--------------------------------------------+  <= key1 offset
+// | key1            | value_size (4 bytes) |   |
+// +----------------------------------------+   |
+// | value1                                     |
+// |                                            |
+// +----------------------------------------+---+  <= key2 offset
+// | key2            | value_size (4 bytes) |   |
+// +----------------------------------------+   |
+// | value2                                     |
+// |                                            |
+// |        ......                              |
+// +-----------------+--------------------------+   <= index_block_offset
+// | key1            | key1 offset (8 bytes)    |
+// +-----------------+--------------------------+
+// | key2            | key2 offset (8 bytes)    |
+// +-----------------+--------------------------+
+// | key3            | key3 offset (8 bytes)    |
+// +-----------------+--------------------------+
+// |        ......                              |
+// +-----------------+------------+-------------+
+// | index_block_offset (8 bytes) |
+// +------------------------------+
+
+// SimpleTable is a simple table format for UNIT TEST ONLY. It is not built
+// as production quality.
+class SimpleTableReader: public TableReader {
+public:
+  // Attempt to open the table that is stored in bytes [0..file_size)
+  // of "file", and read the metadata entries necessary to allow
+  // retrieving data from the table.
+  //
+  // If successful, returns ok and sets "*table" to the newly opened
+  // table.  The client should delete "*table" when no longer needed.
+  // If there was an error while initializing the table, sets "*table"
+  // to nullptr and returns a non-ok status.  Does not take ownership of
+  // "*source", but the client must ensure that "source" remains live
+  // for the duration of the returned table's lifetime.
+  //
+  // *file must remain live while this Table is in use.
+  static Status Open(const Options& options, const EnvOptions& soptions,
+                     unique_ptr<RandomAccessFile> && file, uint64_t file_size,
+                     unique_ptr<TableReader>* table_reader);
+
+  Iterator* NewIterator(const ReadOptions&, Arena* arena) override;
+
+  Status Get(const ReadOptions&, const Slice& key, void* arg,
+             bool (*handle_result)(void* arg, const ParsedInternalKey& k,
+                                   const Slice& v),
+             void (*mark_key_may_exist)(void*) = nullptr) override;
+
+  uint64_t ApproximateOffsetOf(const Slice& key) override;
+
+  void SetupForCompaction() override;
+
+  std::shared_ptr<const TableProperties> GetTableProperties() const override;
+
+  ~SimpleTableReader();
+
+private:
+  struct Rep;
+  Rep* rep_;
+
+  explicit SimpleTableReader(Rep* rep) {
+    rep_ = rep;
+  }
+  friend class TableCache;
+  friend class SimpleTableIterator;
+
+  Status GetOffset(const Slice& target, uint64_t* offset);
+
+  // No copying allowed
+  explicit SimpleTableReader(const TableReader&) = delete;
+  void operator=(const TableReader&) = delete;
+};
+
+// Iterator to iterate SimpleTable
+class SimpleTableIterator: public Iterator {
+public:
+  explicit SimpleTableIterator(SimpleTableReader* table);
+  ~SimpleTableIterator();
+
+  bool Valid() const;
+
+  void SeekToFirst();
+
+  void SeekToLast();
+
+  void Seek(const Slice& target);
+
+  void Next();
+
+  void Prev();
+
+  Slice key() const;
+
+  Slice value() const;
+
+  Status status() const;
+
+private:
+  SimpleTableReader* table_;
+  uint64_t offset_;
+  uint64_t next_offset_;
+  Slice key_;
+  Slice value_;
+  char tmp_str_[4];
+  char* key_str_;
+  char* value_str_;
+  int value_str_len_;
+  Status status_;
+  // No copying allowed
+  SimpleTableIterator(const SimpleTableIterator&) = delete;
+  void operator=(const Iterator&) = delete;
+};
+
+struct SimpleTableReader::Rep {
+  ~Rep() {
+  }
+  Rep(const EnvOptions& storage_options, uint64_t index_start_offset,
+      int num_entries) :
+      soptions(storage_options), index_start_offset(index_start_offset),
+      num_entries(num_entries) {
+  }
+
+  Options options;
+  const EnvOptions& soptions;
+  Status status;
+  unique_ptr<RandomAccessFile> file;
+  uint64_t index_start_offset;
+  int num_entries;
+  std::shared_ptr<TableProperties> table_properties;
+
+  const static int user_key_size = 16;
+  const static int offset_length = 8;
+  const static int key_footer_len = 8;
+
+  static int GetInternalKeyLength() {
+    return user_key_size + key_footer_len;
+  }
+};
+
+SimpleTableReader::~SimpleTableReader() {
+  delete rep_;
+}
+
+Status SimpleTableReader::Open(const Options& options,
+                               const EnvOptions& soptions,
+                               unique_ptr<RandomAccessFile> && file,
+                               uint64_t size,
+                               unique_ptr<TableReader>* table_reader) {
+  char footer_space[Rep::offset_length];
+  Slice footer_input;
+  Status s = file->Read(size - Rep::offset_length, Rep::offset_length,
+                        &footer_input, footer_space);
+  if (s.ok()) {
+    uint64_t index_start_offset = DecodeFixed64(footer_space);
+
+    int num_entries = (size - Rep::offset_length - index_start_offset)
+        / (Rep::GetInternalKeyLength() + Rep::offset_length);
+    SimpleTableReader::Rep* rep = new SimpleTableReader::Rep(soptions,
+                                                             index_start_offset,
+                                                             num_entries);
+
+    rep->file = std::move(file);
+    rep->options = options;
+    table_reader->reset(new SimpleTableReader(rep));
+  }
+  return s;
+}
+
+void SimpleTableReader::SetupForCompaction() {
+}
+
+std::shared_ptr<const TableProperties> SimpleTableReader::GetTableProperties()
+    const {
+  return rep_->table_properties;
+}
+
+Iterator* SimpleTableReader::NewIterator(const ReadOptions& options,
+                                         Arena* arena) {
+  if (arena == nullptr) {
+    return new SimpleTableIterator(this);
+  } else {
+    auto mem = arena->AllocateAligned(sizeof(SimpleTableIterator));
+    return new (mem) SimpleTableIterator(this);
+  }
+}
+
+Status SimpleTableReader::GetOffset(const Slice& target, uint64_t* offset) {
+  uint32_t left = 0;
+  uint32_t right = rep_->num_entries - 1;
+  char key_chars[Rep::GetInternalKeyLength()];
+  Slice tmp_slice;
+
+  uint32_t target_offset = 0;
+  while (left <= right) {
+    uint32_t mid = (left + right + 1) / 2;
+
+    uint64_t offset_to_read = rep_->index_start_offset
+        + (Rep::GetInternalKeyLength() + Rep::offset_length) * mid;
+    Status s = rep_->file->Read(offset_to_read, Rep::GetInternalKeyLength(),
+                                &tmp_slice, key_chars);
+    if (!s.ok()) {
+      return s;
+    }
+
+    InternalKeyComparator ikc(rep_->options.comparator);
+    int compare_result = ikc.Compare(tmp_slice, target);
+
+    if (compare_result < 0) {
+      if (left == right) {
+        target_offset = right + 1;
+        break;
+      }
+      left = mid;
+    } else {
+      if (left == right) {
+        target_offset = left;
+        break;
+      }
+      right = mid - 1;
+    }
+  }
+
+  if (target_offset >= (uint32_t) rep_->num_entries) {
+    *offset = rep_->index_start_offset;
+    return Status::OK();
+  }
+
+  char value_offset_chars[Rep::offset_length];
+
+  int64_t offset_for_value_offset = rep_->index_start_offset
+      + (Rep::GetInternalKeyLength() + Rep::offset_length) * target_offset
+      + Rep::GetInternalKeyLength();
+  Status s = rep_->file->Read(offset_for_value_offset, Rep::offset_length,
+                              &tmp_slice, value_offset_chars);
+  if (s.ok()) {
+    *offset = DecodeFixed64(value_offset_chars);
+  }
+  return s;
+}
+
+Status SimpleTableReader::Get(const ReadOptions& options, const Slice& k,
+                              void* arg,
+                              bool (*saver)(void*, const ParsedInternalKey&,
+                                            const Slice&),
+                              void (*mark_key_may_exist)(void*)) {
+  Status s;
+  SimpleTableIterator* iter = new SimpleTableIterator(this);
+  for (iter->Seek(k); iter->Valid(); iter->Next()) {
+    ParsedInternalKey parsed_key;
+    if (!ParseInternalKey(iter->key(), &parsed_key)) {
+      return Status::Corruption(Slice());
+    }
+
+    if (!(*saver)(arg, parsed_key, iter->value())) {
+      break;
+    }
+  }
+  s = iter->status();
+  delete iter;
+  return s;
+}
+
+uint64_t SimpleTableReader::ApproximateOffsetOf(const Slice& key) {
+  return 0;
+}
+
+SimpleTableIterator::SimpleTableIterator(SimpleTableReader* table) :
+    table_(table) {
+  key_str_ = new char[SimpleTableReader::Rep::GetInternalKeyLength()];
+  value_str_len_ = -1;
+  SeekToFirst();
+}
+
+SimpleTableIterator::~SimpleTableIterator() {
+ delete[] key_str_;
+ if (value_str_len_ >= 0) {
+   delete[] value_str_;
+ }
+}
+
+bool SimpleTableIterator::Valid() const {
+  return offset_ < table_->rep_->index_start_offset;
+}
+
+void SimpleTableIterator::SeekToFirst() {
+  next_offset_ = 0;
+  Next();
+}
+
+void SimpleTableIterator::SeekToLast() {
+  assert(false);
+}
+
+void SimpleTableIterator::Seek(const Slice& target) {
+  Status s = table_->GetOffset(target, &next_offset_);
+  if (!s.ok()) {
+    status_ = s;
+  }
+  Next();
+}
+
+void SimpleTableIterator::Next() {
+  offset_ = next_offset_;
+  if (offset_ >= table_->rep_->index_start_offset) {
+    return;
+  }
+  Slice result;
+  int internal_key_size = SimpleTableReader::Rep::GetInternalKeyLength();
+
+  Status s = table_->rep_->file->Read(next_offset_, internal_key_size, &result,
+                                      key_str_);
+  next_offset_ += internal_key_size;
+  key_ = result;
+
+  Slice value_size_slice;
+  s = table_->rep_->file->Read(next_offset_, 4, &value_size_slice, tmp_str_);
+  next_offset_ += 4;
+  uint32_t value_size = DecodeFixed32(tmp_str_);
+
+  Slice value_slice;
+  if ((int) value_size > value_str_len_) {
+    if (value_str_len_ >= 0) {
+      delete[] value_str_;
+    }
+    value_str_ = new char[value_size];
+    value_str_len_ = value_size;
+  }
+  s = table_->rep_->file->Read(next_offset_, value_size, &value_slice,
+                               value_str_);
+  next_offset_ += value_size;
+  value_ = value_slice;
+}
+
+void SimpleTableIterator::Prev() {
+  assert(false);
+}
+
+Slice SimpleTableIterator::key() const {
+  Log(table_->rep_->options.info_log, "key!!!!");
+  return key_;
+}
+
+Slice SimpleTableIterator::value() const {
+  return value_;
+}
+
+Status SimpleTableIterator::status() const {
+  return status_;
+}
+
+class SimpleTableBuilder: public TableBuilder {
+public:
+  // Create a builder that will store the contents of the table it is
+  // building in *file.  Does not close the file.  It is up to the
+  // caller to close the file after calling Finish(). The output file
+  // will be part of level specified by 'level'.  A value of -1 means
+  // that the caller does not know which level the output file will reside.
+  SimpleTableBuilder(const Options& options, WritableFile* file,
+                     CompressionType compression_type);
+
+  // REQUIRES: Either Finish() or Abandon() has been called.
+  ~SimpleTableBuilder();
+
+  // Add key,value to the table being constructed.
+  // REQUIRES: key is after any previously added key according to comparator.
+  // REQUIRES: Finish(), Abandon() have not been called
+  void Add(const Slice& key, const Slice& value) override;
+
+  // Return non-ok iff some error has been detected.
+  Status status() const override;
+
+  // Finish building the table.  Stops using the file passed to the
+  // constructor after this function returns.
+  // REQUIRES: Finish(), Abandon() have not been called
+  Status Finish() override;
+
+  // Indicate that the contents of this builder should be abandoned.  Stops
+  // using the file passed to the constructor after this function returns.
+  // If the caller is not going to call Finish(), it must call Abandon()
+  // before destroying this builder.
+  // REQUIRES: Finish(), Abandon() have not been called
+  void Abandon() override;
+
+  // Number of calls to Add() so far.
+  uint64_t NumEntries() const override;
+
+  // Size of the file generated so far.  If invoked after a successful
+  // Finish() call, returns the size of the final generated file.
+  uint64_t FileSize() const override;
+
+private:
+  struct Rep;
+  Rep* rep_;
+
+  // No copying allowed
+  SimpleTableBuilder(const SimpleTableBuilder&) = delete;
+  void operator=(const SimpleTableBuilder&) = delete;
+};
+
+struct SimpleTableBuilder::Rep {
+  Options options;
+  WritableFile* file;
+  uint64_t offset = 0;
+  Status status;
+
+  uint64_t num_entries = 0;
+
+  bool closed = false;  // Either Finish() or Abandon() has been called.
+
+  const static int user_key_size = 16;
+  const static int offset_length = 8;
+  const static int key_footer_len = 8;
+
+  static int GetInternalKeyLength() {
+    return user_key_size + key_footer_len;
+  }
+
+  std::string index;
+
+  Rep(const Options& opt, WritableFile* f) :
+      options(opt), file(f) {
+  }
+  ~Rep() {
+  }
+};
+
+SimpleTableBuilder::SimpleTableBuilder(const Options& options,
+                                       WritableFile* file,
+                                       CompressionType compression_type) :
+    rep_(new SimpleTableBuilder::Rep(options, file)) {
+}
+
+SimpleTableBuilder::~SimpleTableBuilder() {
+  delete (rep_);
+}
+
+void SimpleTableBuilder::Add(const Slice& key, const Slice& value) {
+  assert((int ) key.size() == Rep::GetInternalKeyLength());
+
+  // Update index
+  rep_->index.append(key.data(), key.size());
+  PutFixed64(&(rep_->index), rep_->offset);
+
+  // Write key-value pair
+  rep_->file->Append(key);
+  rep_->offset += Rep::GetInternalKeyLength();
+
+  std::string size;
+  int value_size = value.size();
+  PutFixed32(&size, value_size);
+  Slice sizeSlice(size);
+  rep_->file->Append(sizeSlice);
+  rep_->file->Append(value);
+  rep_->offset += value_size + 4;
+
+  rep_->num_entries++;
+}
+
+Status SimpleTableBuilder::status() const {
+  return Status::OK();
+}
+
+Status SimpleTableBuilder::Finish() {
+  Rep* r = rep_;
+  assert(!r->closed);
+  r->closed = true;
+
+  uint64_t index_offset = rep_->offset;
+  Slice index_slice(rep_->index);
+  rep_->file->Append(index_slice);
+  rep_->offset += index_slice.size();
+
+  std::string index_offset_str;
+  PutFixed64(&index_offset_str, index_offset);
+  Slice foot_slice(index_offset_str);
+  rep_->file->Append(foot_slice);
+  rep_->offset += foot_slice.size();
+
+  return Status::OK();
+}
+
+void SimpleTableBuilder::Abandon() {
+  rep_->closed = true;
+}
+
+uint64_t SimpleTableBuilder::NumEntries() const {
+  return rep_->num_entries;
+}
+
+uint64_t SimpleTableBuilder::FileSize() const {
+  return rep_->offset;
+}
+
+class SimpleTableFactory: public TableFactory {
+public:
+  ~SimpleTableFactory() {
+  }
+  SimpleTableFactory() {
+  }
+  const char* Name() const override {
+    return "SimpleTable";
+  }
+  Status NewTableReader(const Options& options, const EnvOptions& soptions,
+                        const InternalKeyComparator& internal_key,
+                        unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
+                        unique_ptr<TableReader>* table_reader) const;
+
+  TableBuilder* NewTableBuilder(const Options& options,
+                                const InternalKeyComparator& internal_key,
+                                WritableFile* file,
+                                CompressionType compression_type) const;
+};
+
+Status SimpleTableFactory::NewTableReader(
+    const Options& options, const EnvOptions& soptions,
+    const InternalKeyComparator& internal_key,
+    unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
+    unique_ptr<TableReader>* table_reader) const {
+
+  return SimpleTableReader::Open(options, soptions, std::move(file), file_size,
+                                 table_reader);
+}
+
+TableBuilder* SimpleTableFactory::NewTableBuilder(
+    const Options& options, const InternalKeyComparator& internal_key,
+    WritableFile* file, CompressionType compression_type) const {
+  return new SimpleTableBuilder(options, file, compression_type);
+}
+
+class SimpleTableDBTest {
+protected:
+public:
+  std::string dbname_;
+  Env* env_;
+  DB* db_;
+
+  Options last_options_;
+
+  SimpleTableDBTest() :
+      env_(Env::Default()) {
+    dbname_ = test::TmpDir() + "/simple_table_db_test";
+    ASSERT_OK(DestroyDB(dbname_, Options()));
+    db_ = nullptr;
+    Reopen();
+  }
+
+  ~SimpleTableDBTest() {
+    delete db_;
+    ASSERT_OK(DestroyDB(dbname_, Options()));
+  }
+
+  // Return the current option configuration.
+  Options CurrentOptions() {
+    Options options;
+    options.table_factory.reset(new SimpleTableFactory());
+    return options;
+  }
+
+  DBImpl* dbfull() {
+    return reinterpret_cast<DBImpl*>(db_);
+  }
+
+  void Reopen(Options* options = nullptr) {
+    ASSERT_OK(TryReopen(options));
+  }
+
+  void Close() {
+    delete db_;
+    db_ = nullptr;
+  }
+
+  void DestroyAndReopen(Options* options = nullptr) {
+    //Destroy using last options
+    Destroy(&last_options_);
+    ASSERT_OK(TryReopen(options));
+  }
+
+  void Destroy(Options* options) {
+    delete db_;
+    db_ = nullptr;
+    ASSERT_OK(DestroyDB(dbname_, *options));
+  }
+
+  Status PureReopen(Options* options, DB** db) {
+    return DB::Open(*options, dbname_, db);
+  }
+
+  Status TryReopen(Options* options = nullptr) {
+    delete db_;
+    db_ = nullptr;
+    Options opts;
+    if (options != nullptr) {
+      opts = *options;
+    } else {
+      opts = CurrentOptions();
+      opts.create_if_missing = true;
+    }
+    last_options_ = opts;
+
+    return DB::Open(opts, dbname_, &db_);
+  }
+
+  Status Put(const Slice& k, const Slice& v) {
+    return db_->Put(WriteOptions(), k, v);
+  }
+
+  Status Delete(const std::string& k) {
+    return db_->Delete(WriteOptions(), k);
+  }
+
+  std::string Get(const std::string& k, const Snapshot* snapshot = nullptr) {
+    ReadOptions options;
+    options.snapshot = snapshot;
+    std::string result;
+    Status s = db_->Get(options, k, &result);
+    if (s.IsNotFound()) {
+      result = "NOT_FOUND";
+    } else if (!s.ok()) {
+      result = s.ToString();
+    }
+    return result;
+  }
+
+
+  int NumTableFilesAtLevel(int level) {
+    std::string property;
+    ASSERT_TRUE(
+        db_->GetProperty("rocksdb.num-files-at-level" + NumberToString(level),
+                         &property));
+    return atoi(property.c_str());
+  }
+
+  // Return spread of files per level
+  std::string FilesPerLevel() {
+    std::string result;
+    int last_non_zero_offset = 0;
+    for (int level = 0; level < db_->NumberLevels(); level++) {
+      int f = NumTableFilesAtLevel(level);
+      char buf[100];
+      snprintf(buf, sizeof(buf), "%s%d", (level ? "," : ""), f);
+      result += buf;
+      if (f > 0) {
+        last_non_zero_offset = result.size();
+      }
+    }
+    result.resize(last_non_zero_offset);
+    return result;
+  }
+
+  std::string IterStatus(Iterator* iter) {
+    std::string result;
+    if (iter->Valid()) {
+      result = iter->key().ToString() + "->" + iter->value().ToString();
+    } else {
+      result = "(invalid)";
+    }
+    return result;
+  }
+};
+
+TEST(SimpleTableDBTest, Empty) {
+  ASSERT_TRUE(db_ != nullptr);
+  ASSERT_EQ("NOT_FOUND", Get("0000000000000foo"));
+}
+
+TEST(SimpleTableDBTest, ReadWrite) {
+  ASSERT_OK(Put("0000000000000foo", "v1"));
+  ASSERT_EQ("v1", Get("0000000000000foo"));
+  ASSERT_OK(Put("0000000000000bar", "v2"));
+  ASSERT_OK(Put("0000000000000foo", "v3"));
+  ASSERT_EQ("v3", Get("0000000000000foo"));
+  ASSERT_EQ("v2", Get("0000000000000bar"));
+}
+
+TEST(SimpleTableDBTest, Flush) {
+  ASSERT_OK(Put("0000000000000foo", "v1"));
+  ASSERT_OK(Put("0000000000000bar", "v2"));
+  ASSERT_OK(Put("0000000000000foo", "v3"));
+  dbfull()->TEST_FlushMemTable();
+  ASSERT_EQ("v3", Get("0000000000000foo"));
+  ASSERT_EQ("v2", Get("0000000000000bar"));
+}
+
+TEST(SimpleTableDBTest, Flush2) {
+  ASSERT_OK(Put("0000000000000bar", "b"));
+  ASSERT_OK(Put("0000000000000foo", "v1"));
+  dbfull()->TEST_FlushMemTable();
+
+  ASSERT_OK(Put("0000000000000foo", "v2"));
+  dbfull()->TEST_FlushMemTable();
+  ASSERT_EQ("v2", Get("0000000000000foo"));
+
+  ASSERT_OK(Put("0000000000000eee", "v3"));
+  dbfull()->TEST_FlushMemTable();
+  ASSERT_EQ("v3", Get("0000000000000eee"));
+
+  ASSERT_OK(Delete("0000000000000bar"));
+  dbfull()->TEST_FlushMemTable();
+  ASSERT_EQ("NOT_FOUND", Get("0000000000000bar"));
+
+  ASSERT_OK(Put("0000000000000eee", "v5"));
+  dbfull()->TEST_FlushMemTable();
+  ASSERT_EQ("v5", Get("0000000000000eee"));
+}
+
+static std::string Key(int i) {
+  char buf[100];
+  snprintf(buf, sizeof(buf), "key_______%06d", i);
+  return std::string(buf);
+}
+
+static std::string RandomString(Random* rnd, int len) {
+  std::string r;
+  test::RandomString(rnd, len, &r);
+  return r;
+}
+
+TEST(SimpleTableDBTest, CompactionTrigger) {
+  Options options = CurrentOptions();
+  options.write_buffer_size = 100 << 10; //100KB
+  options.num_levels = 3;
+  options.max_mem_compaction_level = 0;
+  options.level0_file_num_compaction_trigger = 3;
+  Reopen(&options);
+
+  Random rnd(301);
+
+  for (int num = 0; num < options.level0_file_num_compaction_trigger - 1;
+      num++) {
+    std::vector<std::string> values;
+    // Write 120KB (12 values, each 10K)
+    for (int i = 0; i < 12; i++) {
+      values.push_back(RandomString(&rnd, 10000));
+      ASSERT_OK(Put(Key(i), values[i]));
+    }
+    dbfull()->TEST_WaitForFlushMemTable();
+    ASSERT_EQ(NumTableFilesAtLevel(0), num + 1);
+  }
+
+  //generate one more file in level-0, and should trigger level-0 compaction
+  std::vector<std::string> values;
+  for (int i = 0; i < 12; i++) {
+    values.push_back(RandomString(&rnd, 10000));
+    ASSERT_OK(Put(Key(i), values[i]));
+  }
+  dbfull()->TEST_WaitForCompact();
+
+  ASSERT_EQ(NumTableFilesAtLevel(0), 0);
+  ASSERT_EQ(NumTableFilesAtLevel(1), 1);
+}
+
+}  // namespace rocksdb
+
+int main(int argc, char** argv) {
+  return rocksdb::test::RunAllTests();
+}

db/skiplist.h

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -25,12 +30,12 @@
 // ... prev vs. next pointer ordering ...
 //
 
-#ifndef STORAGE_LEVELDB_DB_SKIPLIST_H_
-#define STORAGE_LEVELDB_DB_SKIPLIST_H_
-
+#pragma once
 #include <assert.h>
 #include <stdlib.h>
+#include "util/arena.h"
 #include "port/port.h"
+#include "util/arena.h"
 #include "util/random.h"
 
 namespace rocksdb {
@@ -44,7 +49,8 @@ class SkipList {
   // Create a new SkipList object that will use "cmp" for comparing keys,
   // and will allocate memory using "*arena".  Objects allocated in the arena
   // must remain allocated for the lifetime of the skiplist object.
-  explicit SkipList(Comparator cmp, Arena* arena);
+  explicit SkipList(Comparator cmp, Arena* arena,
+                    int32_t max_height = 12, int32_t branching_factor = 4);
 
   // Insert key into the list.
   // REQUIRES: nothing that compares equal to key is currently in the list.
@@ -60,6 +66,11 @@ class SkipList {
     // The returned iterator is not valid.
     explicit Iterator(const SkipList* list);
 
+    // Change the underlying skiplist used for this iterator
+    // This enables us not changing the iterator without deallocating
+    // an old one and then allocating a new one
+    void SetList(const SkipList* list);
+
     // Returns true iff the iterator is positioned at a valid node.
     bool Valid() const;
 
@@ -93,7 +104,8 @@ class SkipList {
   };
 
  private:
-  enum { kMaxHeight = 12 };
+  const int32_t kMaxHeight_;
+  const int32_t kBranching_;
 
   // Immutable after construction
   Comparator const compare_;
@@ -106,8 +118,8 @@ class SkipList {
   port::AtomicPointer max_height_;   // Height of the entire list
 
   // Used for optimizing sequential insert patterns
-  Node* prev_[kMaxHeight];
-  int   prev_height_;
+  Node** prev_;
+  int32_t prev_height_;
 
   inline int GetMaxHeight() const {
     return static_cast<int>(
@@ -146,7 +158,7 @@ class SkipList {
 
 // Implementation details follow
 template<typename Key, class Comparator>
-struct SkipList<Key,Comparator>::Node {
+struct SkipList<Key, Comparator>::Node {
   explicit Node(const Key& k) : key(k) { }
 
   Key const key;
@@ -182,38 +194,43 @@ struct SkipList<Key,Comparator>::Node {
 };
 
 template<typename Key, class Comparator>
-typename SkipList<Key,Comparator>::Node*
-SkipList<Key,Comparator>::NewNode(const Key& key, int height) {
+typename SkipList<Key, Comparator>::Node*
+SkipList<Key, Comparator>::NewNode(const Key& key, int height) {
   char* mem = arena_->AllocateAligned(
       sizeof(Node) + sizeof(port::AtomicPointer) * (height - 1));
   return new (mem) Node(key);
 }
 
 template<typename Key, class Comparator>
-inline SkipList<Key,Comparator>::Iterator::Iterator(const SkipList* list) {
+inline SkipList<Key, Comparator>::Iterator::Iterator(const SkipList* list) {
+  SetList(list);
+}
+
+template<typename Key, class Comparator>
+inline void SkipList<Key, Comparator>::Iterator::SetList(const SkipList* list) {
   list_ = list;
   node_ = nullptr;
 }
 
 template<typename Key, class Comparator>
-inline bool SkipList<Key,Comparator>::Iterator::Valid() const {
+inline bool SkipList<Key, Comparator>::Iterator::Valid() const {
   return node_ != nullptr;
 }
 
 template<typename Key, class Comparator>
-inline const Key& SkipList<Key,Comparator>::Iterator::key() const {
+inline const Key& SkipList<Key, Comparator>::Iterator::key() const {
   assert(Valid());
   return node_->key;
 }
 
 template<typename Key, class Comparator>
-inline void SkipList<Key,Comparator>::Iterator::Next() {
+inline void SkipList<Key, Comparator>::Iterator::Next() {
   assert(Valid());
   node_ = node_->Next(0);
 }
 
 template<typename Key, class Comparator>
-inline void SkipList<Key,Comparator>::Iterator::Prev() {
+inline void SkipList<Key, Comparator>::Iterator::Prev() {
   // Instead of using explicit "prev" links, we just search for the
   // last node that falls before key.
   assert(Valid());
@@ -224,17 +241,17 @@ inline void SkipList<Key,Comparator>::Iterator::Prev() {
 }
 
 template<typename Key, class Comparator>
-inline void SkipList<Key,Comparator>::Iterator::Seek(const Key& target) {
+inline void SkipList<Key, Comparator>::Iterator::Seek(const Key& target) {
   node_ = list_->FindGreaterOrEqual(target, nullptr);
 }
 
 template<typename Key, class Comparator>
-inline void SkipList<Key,Comparator>::Iterator::SeekToFirst() {
+inline void SkipList<Key, Comparator>::Iterator::SeekToFirst() {
   node_ = list_->head_->Next(0);
 }
 
 template<typename Key, class Comparator>
-inline void SkipList<Key,Comparator>::Iterator::SeekToLast() {
+inline void SkipList<Key, Comparator>::Iterator::SeekToLast() {
   node_ = list_->FindLast();
   if (node_ == list_->head_) {
     node_ = nullptr;
@@ -242,27 +259,26 @@ inline void SkipList<Key,Comparator>::Iterator::SeekToLast() {
 }
 
 template<typename Key, class Comparator>
-int SkipList<Key,Comparator>::RandomHeight() {
+int SkipList<Key, Comparator>::RandomHeight() {
   // Increase height with probability 1 in kBranching
-  static const unsigned int kBranching = 4;
   int height = 1;
-  while (height < kMaxHeight && ((rnd_.Next() % kBranching) == 0)) {
+  while (height < kMaxHeight_ && ((rnd_.Next() % kBranching_) == 0)) {
     height++;
   }
   assert(height > 0);
-  assert(height <= kMaxHeight);
+  assert(height <= kMaxHeight_);
   return height;
 }
 
 template<typename Key, class Comparator>
-bool SkipList<Key,Comparator>::KeyIsAfterNode(const Key& key, Node* n) const {
+bool SkipList<Key, Comparator>::KeyIsAfterNode(const Key& key, Node* n) const {
   // nullptr n is considered infinite
   return (n != nullptr) && (compare_(n->key, key) < 0);
 }
 
 template<typename Key, class Comparator>
-typename SkipList<Key,Comparator>::Node* SkipList<Key,Comparator>::FindGreaterOrEqual(const Key& key, Node** prev)
-    const {
+typename SkipList<Key, Comparator>::Node* SkipList<Key, Comparator>::
+  FindGreaterOrEqual(const Key& key, Node** prev) const {
   // Use prev as an optimization hint and fallback to slow path
   if (prev && !KeyIsAfterNode(key, prev[0]->Next(0))) {
     Node* x = prev[0];
@@ -299,8 +315,8 @@ typename SkipList<Key,Comparator>::Node* SkipList<Key,Comparator>::FindGreaterOr
 }
 
 template<typename Key, class Comparator>
-typename SkipList<Key,Comparator>::Node*
-SkipList<Key,Comparator>::FindLessThan(const Key& key) const {
+typename SkipList<Key, Comparator>::Node*
+SkipList<Key, Comparator>::FindLessThan(const Key& key) const {
   Node* x = head_;
   int level = GetMaxHeight() - 1;
   while (true) {
@@ -320,7 +336,7 @@ SkipList<Key,Comparator>::FindLessThan(const Key& key) const {
 }
 
 template<typename Key, class Comparator>
-typename SkipList<Key,Comparator>::Node* SkipList<Key,Comparator>::FindLast()
+typename SkipList<Key, Comparator>::Node* SkipList<Key, Comparator>::FindLast()
     const {
   Node* x = head_;
   int level = GetMaxHeight() - 1;
@@ -340,21 +356,31 @@ typename SkipList<Key,Comparator>::Node* SkipList<Key,Comparator>::FindLast()
 }
 
 template<typename Key, class Comparator>
-SkipList<Key,Comparator>::SkipList(Comparator cmp, Arena* arena)
-    : compare_(cmp),
+SkipList<Key, Comparator>::SkipList(const Comparator cmp, Arena* arena,
+                                   int32_t max_height,
+                                   int32_t branching_factor)
+    : kMaxHeight_(max_height),
+      kBranching_(branching_factor),
+      compare_(cmp),
       arena_(arena),
-      head_(NewNode(0 /* any key will do */, kMaxHeight)),
+      head_(NewNode(0 /* any key will do */, max_height)),
       max_height_(reinterpret_cast<void*>(1)),
       prev_height_(1),
       rnd_(0xdeadbeef) {
-  for (int i = 0; i < kMaxHeight; i++) {
+  assert(kMaxHeight_ > 0);
+  assert(kBranching_ > 0);
+  // Allocate the prev_ Node* array, directly from the passed-in arena.
+  // prev_ does not need to be freed, as its life cycle is tied up with
+  // the arena as a whole.
+  prev_ = (Node**) arena_->AllocateAligned(sizeof(Node*) * kMaxHeight_);
+  for (int i = 0; i < kMaxHeight_; i++) {
     head_->SetNext(i, nullptr);
     prev_[i] = head_;
   }
 }
 
 template<typename Key, class Comparator>
-void SkipList<Key,Comparator>::Insert(const Key& key) {
+void SkipList<Key, Comparator>::Insert(const Key& key) {
   // TODO(opt): We can use a barrier-free variant of FindGreaterOrEqual()
   // here since Insert() is externally synchronized.
   Node* x = FindGreaterOrEqual(key, prev_);
@@ -391,7 +417,7 @@ void SkipList<Key,Comparator>::Insert(const Key& key) {
 }
 
 template<typename Key, class Comparator>
-bool SkipList<Key,Comparator>::Contains(const Key& key) const {
+bool SkipList<Key, Comparator>::Contains(const Key& key) const {
   Node* x = FindGreaterOrEqual(key, nullptr);
   if (x != nullptr && Equal(key, x->key)) {
     return true;
@@ -401,5 +427,3 @@ bool SkipList<Key,Comparator>::Contains(const Key& key) const {
 }
 
 }  // namespace rocksdb
-
-#endif // STORAGE_LEVELDB_DB_SKIPLIST_H_

db/skiplist_test.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -5,7 +10,7 @@
 #include "db/skiplist.h"
 #include <set>
 #include "rocksdb/env.h"
-#include "util/arena_impl.h"
+#include "util/arena.h"
 #include "util/hash.h"
 #include "util/random.h"
 #include "util/testharness.h"
@@ -29,9 +34,9 @@ struct TestComparator {
 class SkipTest { };
 
 TEST(SkipTest, Empty) {
-  ArenaImpl arena_impl;
+  Arena arena;
   TestComparator cmp;
-  SkipList<Key, TestComparator> list(cmp, &arena_impl);
+  SkipList<Key, TestComparator> list(cmp, &arena);
   ASSERT_TRUE(!list.Contains(10));
 
   SkipList<Key, TestComparator>::Iterator iter(&list);
@@ -49,9 +54,9 @@ TEST(SkipTest, InsertAndLookup) {
   const int R = 5000;
   Random rnd(1000);
   std::set<Key> keys;
-  ArenaImpl arena_impl;
+  Arena arena;
   TestComparator cmp;
-  SkipList<Key, TestComparator> list(cmp, &arena_impl);
+  SkipList<Key, TestComparator> list(cmp, &arena);
   for (int i = 0; i < N; i++) {
     Key key = rnd.Next() % R;
     if (keys.insert(key).second) {
@@ -204,14 +209,14 @@ class ConcurrentTest {
   // Current state of the test
   State current_;
 
-  ArenaImpl arena_impl_;
+  Arena arena_;
 
   // SkipList is not protected by mu_.  We just use a single writer
   // thread to modify it.
   SkipList<Key, TestComparator> list_;
 
  public:
-  ConcurrentTest() : list_(TestComparator(), &arena_impl_) { }
+  ConcurrentTest() : list_(TestComparator(), &arena_) {}
 
   // REQUIRES: External synchronization
   void WriteStep(Random* rnd) {

db/snapshot.h

@@ -1,10 +1,13 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 
-#ifndef STORAGE_LEVELDB_DB_SNAPSHOT_H_
-#define STORAGE_LEVELDB_DB_SNAPSHOT_H_
-
+#pragma once
 #include "rocksdb/db.h"
 
 namespace rocksdb {
@@ -81,5 +84,3 @@ class SnapshotList {
 };
 
 }  // namespace rocksdb
-
-#endif  // STORAGE_LEVELDB_DB_SNAPSHOT_H_

db/table_cache.cc

@@ -1,3 +1,8 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
@@ -5,17 +10,19 @@
 #include "db/table_cache.h"
 
 #include "db/filename.h"
+#include "db/version_edit.h"
 
 #include "rocksdb/statistics.h"
-#include "table/table.h"
+#include "table/iterator_wrapper.h"
+#include "table/table_reader.h"
 #include "util/coding.h"
 #include "util/stop_watch.h"
 
 namespace rocksdb {
 
 static void DeleteEntry(const Slice& key, void* value) {
-  Table* table = reinterpret_cast<Table*>(value);
-  delete table;
+  TableReader* table_reader = reinterpret_cast<TableReader*>(value);
+  delete table_reader;
 }
 
 static void UnrefEntry(void* arg1, void* arg2) {
@@ -24,56 +31,66 @@ static void UnrefEntry(void* arg1, void* arg2) {
   cache->Release(h);
 }
 
-TableCache::TableCache(const std::string& dbname,
-                       const Options* options,
-                       const EnvOptions& storage_options,
-                       int entries)
+static Slice GetSliceForFileNumber(const uint64_t* file_number) {
+  return Slice(reinterpret_cast<const char*>(file_number),
+               sizeof(*file_number));
+}
+
+TableCache::TableCache(const Options* options,
+                       const EnvOptions& storage_options, Cache* const cache)
     : env_(options->env),
-      dbname_(dbname),
+      db_paths_(options->db_paths),
       options_(options),
       storage_options_(storage_options),
-      cache_(NewLRUCache(entries, options->table_cache_numshardbits)) {}
+      cache_(cache) {}
 
 TableCache::~TableCache() {
 }
 
+TableReader* TableCache::GetTableReaderFromHandle(Cache::Handle* handle) {
+  return reinterpret_cast<TableReader*>(cache_->Value(handle));
+}
+
+void TableCache::ReleaseHandle(Cache::Handle* handle) {
+  cache_->Release(handle);
+}
+
 Status TableCache::FindTable(const EnvOptions& toptions,
-                             uint64_t file_number, uint64_t file_size,
-                             Cache::Handle** handle, bool* table_io,
+                             const InternalKeyComparator& internal_comparator,
+                             const FileDescriptor& fd, Cache::Handle** handle,
                              const bool no_io) {
   Status s;
-  char buf[sizeof(file_number)];
-  EncodeFixed64(buf, file_number);
-  Slice key(buf, sizeof(buf));
+  uint64_t number = fd.GetNumber();
+  Slice key = GetSliceForFileNumber(&number);
   *handle = cache_->Lookup(key);
   if (*handle == nullptr) {
     if (no_io) { // Dont do IO and return a not-found status
       return Status::Incomplete("Table not found in table_cache, no_io is set");
     }
-    if (table_io != nullptr) {
-      *table_io = true;    // we had to do IO from storage
-    }
-    std::string fname = TableFileName(dbname_, file_number);
+    std::string fname =
+        TableFileName(db_paths_, fd.GetNumber(), fd.GetPathId());
     unique_ptr<RandomAccessFile> file;
-    unique_ptr<Table> table;
+    unique_ptr<TableReader> table_reader;
     s = env_->NewRandomAccessFile(fname, &file, toptions);
-    RecordTick(options_->statistics, NO_FILE_OPENS);
+    RecordTick(options_->statistics.get(), NO_FILE_OPENS);
     if (s.ok()) {
       if (options_->advise_random_on_open) {
         file->Hint(RandomAccessFile::RANDOM);
       }
-      StopWatch sw(env_, options_->statistics, TABLE_OPEN_IO_MICROS);
-      s = Table::Open(*options_, toptions, std::move(file), file_size, &table);
+      StopWatch sw(env_, options_->statistics.get(), TABLE_OPEN_IO_MICROS);
+      s = options_->table_factory->NewTableReader(
+          *options_, toptions, internal_comparator, std::move(file),
+          fd.GetFileSize(), &table_reader);
     }
 
     if (!s.ok()) {
-      assert(table == nullptr);
-      RecordTick(options_->statistics, NO_FILE_ERRORS);
+      assert(table_reader == nullptr);
+      RecordTick(options_->statistics.get(), NO_FILE_ERRORS);
       // We do not cache error results so that if the error is transient,
       // or somebody repairs the file, we recover automatically.
     } else {
       assert(file.get() == nullptr);
-      *handle = cache_->Insert(key, table.release(), 1, &DeleteEntry);
+      *handle = cache_->Insert(key, table_reader.release(), 1, &DeleteEntry);
     }
   }
   return s;
@@ -81,53 +98,61 @@ Status TableCache::FindTable(const EnvOptions& toptions,
 
 Iterator* TableCache::NewIterator(const ReadOptions& options,
                                   const EnvOptions& toptions,
-                                  uint64_t file_number,
-                                  uint64_t file_size,
-                                  Table** tableptr,
-                                  bool for_compaction) {
-  if (tableptr != nullptr) {
-    *tableptr = nullptr;
+                                  const InternalKeyComparator& icomparator,
+                                  const FileDescriptor& fd,
+                                  TableReader** table_reader_ptr,
+                                  bool for_compaction, Arena* arena) {
+  if (table_reader_ptr != nullptr) {
+    *table_reader_ptr = nullptr;
   }
-
+  TableReader* table_reader = fd.table_reader;
   Cache::Handle* handle = nullptr;
-  Status s = FindTable(toptions, file_number, file_size, &handle,
-                       nullptr, options.read_tier == kBlockCacheTier);
-  if (!s.ok()) {
-    return NewErrorIterator(s);
+  Status s;
+  if (table_reader == nullptr) {
+    s = FindTable(toptions, icomparator, fd, &handle,
+                  options.read_tier == kBlockCacheTier);
+    if (!s.ok()) {
+      return NewErrorIterator(s, arena);
+    }
+    table_reader = GetTableReaderFromHandle(handle);
   }
 
-  Table* table =
-    reinterpret_cast<Table*>(cache_->Value(handle));
-  Iterator* result = table->NewIterator(options);
-  result->RegisterCleanup(&UnrefEntry, cache_.get(), handle);
-  if (tableptr != nullptr) {
-    *tableptr = table;
+  Iterator* result = table_reader->NewIterator(options, arena);
+  if (handle != nullptr) {
+    result->RegisterCleanup(&UnrefEntry, cache_, handle);
+  }
+  if (table_reader_ptr != nullptr) {
+    *table_reader_ptr = table_reader;
   }
 
   if (for_compaction) {
-    table->SetupForCompaction();
+    table_reader->SetupForCompaction();
   }
 
   return result;
 }
 
 Status TableCache::Get(const ReadOptions& options,
-                       uint64_t file_number,
-                       uint64_t file_size,
-                       const Slice& k,
-                       void* arg,
-                       bool (*saver)(void*, const Slice&, const Slice&, bool),
-                       bool* table_io,
+                       const InternalKeyComparator& internal_comparator,
+                       const FileDescriptor& fd, const Slice& k, void* arg,
+                       bool (*saver)(void*, const ParsedInternalKey&,
+                                     const Slice&),
                        void (*mark_key_may_exist)(void*)) {
+  TableReader* t = fd.table_reader;
+  Status s;
   Cache::Handle* handle = nullptr;
-  Status s = FindTable(storage_options_, file_number, file_size,
-                       &handle, table_io,
-                       options.read_tier == kBlockCacheTier);
+  if (!t) {
+    s = FindTable(storage_options_, internal_comparator, fd, &handle,
+                  options.read_tier == kBlockCacheTier);
+    if (s.ok()) {
+      t = GetTableReaderFromHandle(handle);
+    }
+  }
   if (s.ok()) {
-    Table* t =
-      reinterpret_cast<Table*>(cache_->Value(handle));
-    s = t->InternalGet(options, k, arg, saver, mark_key_may_exist);
-    cache_->Release(handle);
+    s = t->Get(options, k, arg, saver, mark_key_may_exist);
+    if (handle != nullptr) {
+      ReleaseHandle(handle);
+    }
   } else if (options.read_tier && s.IsIncomplete()) {
     // Couldnt find Table in cache but treat as kFound if no_io set
     (*mark_key_may_exist)(arg);
@@ -135,29 +160,33 @@ Status TableCache::Get(const ReadOptions& options,
   }
   return s;
 }
+Status TableCache::GetTableProperties(
+    const EnvOptions& toptions,
+    const InternalKeyComparator& internal_comparator, const FileDescriptor& fd,
+    std::shared_ptr<const TableProperties>* properties, bool no_io) {
+  Status s;
+  auto table_reader = fd.table_reader;
+  // table already been pre-loaded?
+  if (table_reader) {
+    *properties = table_reader->GetTableProperties();
 
-bool TableCache::PrefixMayMatch(const ReadOptions& options,
-                                uint64_t file_number,
-                                uint64_t file_size,
-                                const Slice& internal_prefix,
-                                bool* table_io) {
-  Cache::Handle* handle = nullptr;
-  Status s = FindTable(storage_options_, file_number,
-                       file_size, &handle, table_io);
-  bool may_match = true;
-  if (s.ok()) {
-    Table* t =
-      reinterpret_cast<Table*>(cache_->Value(handle));
-    may_match = t->PrefixMayMatch(internal_prefix);
-    cache_->Release(handle);
+    return s;
   }
-  return may_match;
+
+  Cache::Handle* table_handle = nullptr;
+  s = FindTable(toptions, internal_comparator, fd, &table_handle, no_io);
+  if (!s.ok()) {
+    return s;
+  }
+  assert(table_handle);
+  auto table = GetTableReaderFromHandle(table_handle);
+  *properties = table->GetTableProperties();
+  ReleaseHandle(table_handle);
+  return s;
 }
 
-void TableCache::Evict(uint64_t file_number) {
-  char buf[sizeof(file_number)];
-  EncodeFixed64(buf, file_number);
-  cache_->Erase(Slice(buf, sizeof(buf)));
+void TableCache::Evict(Cache* cache, uint64_t file_number) {
+  cache->Erase(GetSliceForFileNumber(&file_number));
 }
 
 }  // namespace rocksdb

db/table_cache.h

@@ -1,28 +1,36 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file. See the AUTHORS file for names of contributors.
 //
 // Thread-safe (provides internal synchronization)
 
-#ifndef STORAGE_LEVELDB_DB_TABLE_CACHE_H_
-#define STORAGE_LEVELDB_DB_TABLE_CACHE_H_
-
+#pragma once
 #include <string>
+#include <vector>
 #include <stdint.h>
+
 #include "db/dbformat.h"
-#include "rocksdb/env.h"
-#include "rocksdb/cache.h"
 #include "port/port.h"
-#include "table/table.h"
+#include "rocksdb/cache.h"
+#include "rocksdb/env.h"
+#include "rocksdb/table.h"
+#include "table/table_reader.h"
 
 namespace rocksdb {
 
 class Env;
+class Arena;
+struct FileDescriptor;
 
 class TableCache {
  public:
-  TableCache(const std::string& dbname, const Options* options,
-             const EnvOptions& storage_options, int entries);
+  TableCache(const Options* options, const EnvOptions& storage_options,
+             Cache* cache);
   ~TableCache();
 
   // Return an iterator for the specified file number (the corresponding
@@ -32,46 +40,55 @@ class TableCache {
   // the returned iterator.  The returned "*tableptr" object is owned by
   // the cache and should not be deleted, and is valid for as long as the
   // returned iterator is live.
-  Iterator* NewIterator(const ReadOptions& options,
-                        const EnvOptions& toptions,
-                        uint64_t file_number,
-                        uint64_t file_size,
-                        Table** tableptr = nullptr,
-                        bool for_compaction = false);
+  Iterator* NewIterator(const ReadOptions& options, const EnvOptions& toptions,
+                        const InternalKeyComparator& internal_comparator,
+                        const FileDescriptor& file_fd,
+                        TableReader** table_reader_ptr = nullptr,
+                        bool for_compaction = false, Arena* arena = nullptr);
 
   // If a seek to internal key "k" in specified file finds an entry,
   // call (*handle_result)(arg, found_key, found_value) repeatedly until
   // it returns false.
   Status Get(const ReadOptions& options,
-             uint64_t file_number,
-             uint64_t file_size,
-             const Slice& k,
-             void* arg,
-             bool (*handle_result)(void*, const Slice&, const Slice&, bool),
-             bool* table_io,
+             const InternalKeyComparator& internal_comparator,
+             const FileDescriptor& file_fd, const Slice& k, void* arg,
+             bool (*handle_result)(void*, const ParsedInternalKey&,
+                                   const Slice&),
              void (*mark_key_may_exist)(void*) = nullptr);
 
-  // Determine whether the table may contain the specified prefix.  If
-  // the table index of blooms are not in memory, this may cause an I/O
-  bool PrefixMayMatch(const ReadOptions& options, uint64_t file_number,
-                      uint64_t file_size, const Slice& internal_prefix,
-                      bool* table_io);
-
   // Evict any entry for the specified file number
-  void Evict(uint64_t file_number);
+  static void Evict(Cache* cache, uint64_t file_number);
+
+  // Find table reader
+  Status FindTable(const EnvOptions& toptions,
+                   const InternalKeyComparator& internal_comparator,
+                   const FileDescriptor& file_fd, Cache::Handle**,
+                   const bool no_io = false);
+
+  // Get TableReader from a cache handle.
+  TableReader* GetTableReaderFromHandle(Cache::Handle* handle);
+
+  // Get the table properties of a given table.
+  // @no_io: indicates if we should load table to the cache if it is not present
+  //         in table cache yet.
+  // @returns: `properties` will be reset on success. Please note that we will
+  //            return Status::Incomplete() if table is not present in cache and
+  //            we set `no_io` to be true.
+  Status GetTableProperties(const EnvOptions& toptions,
+                            const InternalKeyComparator& internal_comparator,
+                            const FileDescriptor& file_meta,
+                            std::shared_ptr<const TableProperties>* properties,
+                            bool no_io = false);
+
+  // Release the handle from a cache
+  void ReleaseHandle(Cache::Handle* handle);
 
  private:
   Env* const env_;
-  const std::string dbname_;
+  const std::vector<std::string> db_paths_;
   const Options* options_;
   const EnvOptions& storage_options_;
-  std::shared_ptr<Cache> cache_;
-
-  Status FindTable(const EnvOptions& toptions, uint64_t file_number,
-                   uint64_t file_size, Cache::Handle**, bool* table_io=nullptr,
-                   const bool no_io = false);
+  Cache* const cache_;
 };
 
 }  // namespace rocksdb
-
-#endif  // STORAGE_LEVELDB_DB_TABLE_CACHE_H_

db/table_properties_collector.cc

@@ -0,0 +1,83 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+
+#include "db/table_properties_collector.h"
+
+#include "db/dbformat.h"
+#include "util/coding.h"
+
+namespace rocksdb {
+
+Status InternalKeyPropertiesCollector::Add(
+    const Slice& key, const Slice& value) {
+  ParsedInternalKey ikey;
+  if (!ParseInternalKey(key, &ikey)) {
+    return Status::InvalidArgument("Invalid internal key");
+  }
+
+  if (ikey.type == ValueType::kTypeDeletion) {
+    ++deleted_keys_;
+  }
+
+  return Status::OK();
+}
+
+Status InternalKeyPropertiesCollector::Finish(
+    UserCollectedProperties* properties) {
+  assert(properties);
+  assert(properties->find(
+        InternalKeyTablePropertiesNames::kDeletedKeys) == properties->end());
+  std::string val;
+
+  PutVarint64(&val, deleted_keys_);
+  properties->insert({ InternalKeyTablePropertiesNames::kDeletedKeys, val });
+
+  return Status::OK();
+}
+
+UserCollectedProperties
+InternalKeyPropertiesCollector::GetReadableProperties() const {
+  return {
+    { "kDeletedKeys", std::to_string(deleted_keys_) }
+  };
+}
+
+
+Status UserKeyTablePropertiesCollector::Add(
+    const Slice& key, const Slice& value) {
+  ParsedInternalKey ikey;
+  if (!ParseInternalKey(key, &ikey)) {
+    return Status::InvalidArgument("Invalid internal key");
+  }
+
+  return collector_->Add(ikey.user_key, value);
+}
+
+Status UserKeyTablePropertiesCollector::Finish(
+    UserCollectedProperties* properties) {
+  return collector_->Finish(properties);
+}
+
+UserCollectedProperties
+UserKeyTablePropertiesCollector::GetReadableProperties() const {
+  return collector_->GetReadableProperties();
+}
+
+
+const std::string InternalKeyTablePropertiesNames::kDeletedKeys
+  = "rocksdb.deleted.keys";
+
+uint64_t GetDeletedKeys(
+    const UserCollectedProperties& props) {
+  auto pos = props.find(InternalKeyTablePropertiesNames::kDeletedKeys);
+  if (pos == props.end()) {
+    return 0;
+  }
+  Slice raw = pos->second;
+  uint64_t val = 0;
+  return GetVarint64(&raw, &val) ? val : 0;
+}
+
+}  // namespace rocksdb

db/table_properties_collector.h

@@ -0,0 +1,95 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+// This file defines a collection of statistics collectors.
+#pragma once
+
+#include "rocksdb/table_properties.h"
+
+#include <memory>
+#include <string>
+#include <vector>
+
+namespace rocksdb {
+
+struct InternalKeyTablePropertiesNames {
+  static const std::string kDeletedKeys;
+};
+
+// Collecting the statistics for internal keys. Visible only by internal
+// rocksdb modules.
+class InternalKeyPropertiesCollector : public TablePropertiesCollector {
+ public:
+  virtual Status Add(const Slice& key, const Slice& value) override;
+
+  virtual Status Finish(UserCollectedProperties* properties) override;
+
+  virtual const char* Name() const override {
+    return "InternalKeyPropertiesCollector";
+  }
+
+  UserCollectedProperties GetReadableProperties() const override;
+
+ private:
+  uint64_t deleted_keys_ = 0;
+};
+
+class InternalKeyPropertiesCollectorFactory
+    : public TablePropertiesCollectorFactory {
+ public:
+  virtual TablePropertiesCollector* CreateTablePropertiesCollector() {
+    return new InternalKeyPropertiesCollector();
+  }
+
+  virtual const char* Name() const override {
+    return "InternalKeyPropertiesCollectorFactory";
+  }
+};
+
+// When rocksdb creates a new table, it will encode all "user keys" into
+// "internal keys", which contains meta information of a given entry.
+//
+// This class extracts user key from the encoded internal key when Add() is
+// invoked.
+class UserKeyTablePropertiesCollector : public TablePropertiesCollector {
+ public:
+  // transfer of ownership
+  explicit UserKeyTablePropertiesCollector(TablePropertiesCollector* collector)
+      : collector_(collector) {}
+
+  virtual ~UserKeyTablePropertiesCollector() {}
+
+  virtual Status Add(const Slice& key, const Slice& value) override;
+
+  virtual Status Finish(UserCollectedProperties* properties) override;
+
+  virtual const char* Name() const override { return collector_->Name(); }
+
+  UserCollectedProperties GetReadableProperties() const override;
+
+ protected:
+  std::unique_ptr<TablePropertiesCollector> collector_;
+};
+
+class UserKeyTablePropertiesCollectorFactory
+    : public TablePropertiesCollectorFactory {
+ public:
+  explicit UserKeyTablePropertiesCollectorFactory(
+      std::shared_ptr<TablePropertiesCollectorFactory> user_collector_factory)
+      : user_collector_factory_(user_collector_factory) {}
+  virtual TablePropertiesCollector* CreateTablePropertiesCollector() {
+    return new UserKeyTablePropertiesCollector(
+        user_collector_factory_->CreateTablePropertiesCollector());
+  }
+
+  virtual const char* Name() const override {
+    return user_collector_factory_->Name();
+  }
+
+ private:
+  std::shared_ptr<TablePropertiesCollectorFactory> user_collector_factory_;
+};
+
+}  // namespace rocksdb

db/table_properties_collector_test.cc

@@ -0,0 +1,313 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+
+#include <map>
+#include <memory>
+#include <string>
+
+#include "db/db_impl.h"
+#include "db/dbformat.h"
+#include "db/table_properties_collector.h"
+#include "rocksdb/table.h"
+#include "table/block_based_table_factory.h"
+#include "table/meta_blocks.h"
+#include "table/plain_table_factory.h"
+#include "table/table_builder.h"
+#include "util/coding.h"
+#include "util/testharness.h"
+#include "util/testutil.h"
+
+namespace rocksdb {
+
+class TablePropertiesTest {
+};
+
+// TODO(kailiu) the following classes should be moved to some more general
+// places, so that other tests can also make use of them.
+// `FakeWritableFile` and `FakeRandomeAccessFile` bypass the real file system
+// and therefore enable us to quickly setup the tests.
+class FakeWritableFile : public WritableFile {
+ public:
+  ~FakeWritableFile() { }
+
+  const std::string& contents() const { return contents_; }
+
+  virtual Status Close() { return Status::OK(); }
+  virtual Status Flush() { return Status::OK(); }
+  virtual Status Sync() { return Status::OK(); }
+
+  virtual Status Append(const Slice& data) {
+    contents_.append(data.data(), data.size());
+    return Status::OK();
+  }
+
+ private:
+  std::string contents_;
+};
+
+
+class FakeRandomeAccessFile : public RandomAccessFile {
+ public:
+  explicit FakeRandomeAccessFile(const Slice& contents)
+      : contents_(contents.data(), contents.size()) {
+  }
+
+  virtual ~FakeRandomeAccessFile() { }
+
+  uint64_t Size() const { return contents_.size(); }
+
+  virtual Status Read(uint64_t offset, size_t n, Slice* result,
+                       char* scratch) const {
+    if (offset > contents_.size()) {
+      return Status::InvalidArgument("invalid Read offset");
+    }
+    if (offset + n > contents_.size()) {
+      n = contents_.size() - offset;
+    }
+    memcpy(scratch, &contents_[offset], n);
+    *result = Slice(scratch, n);
+    return Status::OK();
+  }
+
+ private:
+  std::string contents_;
+};
+
+
+class DumbLogger : public Logger {
+ public:
+  virtual void Logv(const char* format, va_list ap) { }
+  virtual size_t GetLogFileSize() const { return 0; }
+};
+
+// Utilities test functions
+namespace {
+void MakeBuilder(const Options& options,
+                 const InternalKeyComparator& internal_comparator,
+                 std::unique_ptr<FakeWritableFile>* writable,
+                 std::unique_ptr<TableBuilder>* builder) {
+  writable->reset(new FakeWritableFile);
+  builder->reset(options.table_factory->NewTableBuilder(
+      options, internal_comparator, writable->get(), options.compression));
+}
+}  // namespace
+
+// Collects keys that starts with "A" in a table.
+class RegularKeysStartWithA: public TablePropertiesCollector {
+ public:
+   const char* Name() const { return "RegularKeysStartWithA"; }
+
+   Status Finish(UserCollectedProperties* properties) {
+     std::string encoded;
+     PutVarint32(&encoded, count_);
+     *properties = UserCollectedProperties {
+       { "TablePropertiesTest", "Rocksdb" },
+       { "Count", encoded }
+     };
+     return Status::OK();
+   }
+
+   Status Add(const Slice& user_key, const Slice& value) {
+     // simply asssume all user keys are not empty.
+     if (user_key.data()[0] == 'A') {
+       ++count_;
+     }
+     return Status::OK();
+   }
+
+  virtual UserCollectedProperties GetReadableProperties() const {
+    return UserCollectedProperties{};
+  }
+
+ private:
+  uint32_t count_ = 0;
+};
+
+class RegularKeysStartWithAFactory : public TablePropertiesCollectorFactory {
+ public:
+  virtual TablePropertiesCollector* CreateTablePropertiesCollector() {
+    return new RegularKeysStartWithA();
+  }
+  const char* Name() const { return "RegularKeysStartWithA"; }
+};
+
+extern uint64_t kBlockBasedTableMagicNumber;
+extern uint64_t kPlainTableMagicNumber;
+namespace {
+void TestCustomizedTablePropertiesCollector(
+    uint64_t magic_number, bool encode_as_internal, const Options& options,
+    const InternalKeyComparator& internal_comparator) {
+  // make sure the entries will be inserted with order.
+  std::map<std::string, std::string> kvs = {
+    {"About   ", "val5"},  // starts with 'A'
+    {"Abstract", "val2"},  // starts with 'A'
+    {"Around  ", "val7"},  // starts with 'A'
+    {"Beyond  ", "val3"},
+    {"Builder ", "val1"},
+    {"Cancel  ", "val4"},
+    {"Find    ", "val6"},
+  };
+
+  // -- Step 1: build table
+  std::unique_ptr<TableBuilder> builder;
+  std::unique_ptr<FakeWritableFile> writable;
+  MakeBuilder(options, internal_comparator, &writable, &builder);
+
+  for (const auto& kv : kvs) {
+    if (encode_as_internal) {
+      InternalKey ikey(kv.first, 0, ValueType::kTypeValue);
+      builder->Add(ikey.Encode(), kv.second);
+    } else {
+      builder->Add(kv.first, kv.second);
+    }
+  }
+  ASSERT_OK(builder->Finish());
+
+  // -- Step 2: Read properties
+  FakeRandomeAccessFile readable(writable->contents());
+  TableProperties* props;
+  Status s = ReadTableProperties(
+      &readable,
+      writable->contents().size(),
+      magic_number,
+      Env::Default(),
+      nullptr,
+      &props
+  );
+  std::unique_ptr<TableProperties> props_guard(props);
+  ASSERT_OK(s);
+
+  auto user_collected = props->user_collected_properties;
+
+  ASSERT_EQ("Rocksdb", user_collected.at("TablePropertiesTest"));
+
+  uint32_t starts_with_A = 0;
+  Slice key(user_collected.at("Count"));
+  ASSERT_TRUE(GetVarint32(&key, &starts_with_A));
+  ASSERT_EQ(3u, starts_with_A);
+}
+}  // namespace
+
+TEST(TablePropertiesTest, CustomizedTablePropertiesCollector) {
+  // Test properties collectors with internal keys or regular keys
+  // for block based table
+  for (bool encode_as_internal : { true, false }) {
+    Options options;
+    std::shared_ptr<TablePropertiesCollectorFactory> collector_factory(
+        new RegularKeysStartWithAFactory());
+    if (encode_as_internal) {
+      options.table_properties_collector_factories.emplace_back(
+          new UserKeyTablePropertiesCollectorFactory(collector_factory));
+    } else {
+      options.table_properties_collector_factories.resize(1);
+      options.table_properties_collector_factories[0] = collector_factory;
+    }
+    test::PlainInternalKeyComparator ikc(options.comparator);
+    TestCustomizedTablePropertiesCollector(kBlockBasedTableMagicNumber,
+                                           encode_as_internal, options, ikc);
+  }
+
+  // test plain table
+  Options options;
+  options.table_properties_collector_factories.emplace_back(
+      new RegularKeysStartWithAFactory());
+  options.table_factory = std::make_shared<PlainTableFactory>(8, 8, 0);
+  test::PlainInternalKeyComparator ikc(options.comparator);
+  TestCustomizedTablePropertiesCollector(kPlainTableMagicNumber, true, options,
+                                         ikc);
+}
+
+namespace {
+void TestInternalKeyPropertiesCollector(
+    uint64_t magic_number,
+    bool sanitized,
+    std::shared_ptr<TableFactory> table_factory) {
+  InternalKey keys[] = {
+    InternalKey("A       ", 0, ValueType::kTypeValue),
+    InternalKey("B       ", 0, ValueType::kTypeValue),
+    InternalKey("C       ", 0, ValueType::kTypeValue),
+    InternalKey("W       ", 0, ValueType::kTypeDeletion),
+    InternalKey("X       ", 0, ValueType::kTypeDeletion),
+    InternalKey("Y       ", 0, ValueType::kTypeDeletion),
+    InternalKey("Z       ", 0, ValueType::kTypeDeletion),
+  };
+
+  std::unique_ptr<TableBuilder> builder;
+  std::unique_ptr<FakeWritableFile> writable;
+  Options options;
+  test::PlainInternalKeyComparator pikc(options.comparator);
+
+  options.table_factory = table_factory;
+  if (sanitized) {
+    options.table_properties_collector_factories.emplace_back(
+        new RegularKeysStartWithAFactory());
+    // with sanitization, even regular properties collector will be able to
+    // handle internal keys.
+    auto comparator = options.comparator;
+    // HACK: Set options.info_log to avoid writing log in
+    // SanitizeOptions().
+    options.info_log = std::make_shared<DumbLogger>();
+    options = SanitizeOptions("db",            // just a place holder
+                              &pikc, nullptr,  // don't care filter policy
+                              options);
+    options.comparator = comparator;
+  } else {
+    options.table_properties_collector_factories = {
+        std::make_shared<InternalKeyPropertiesCollectorFactory>()};
+  }
+
+  for (int iter = 0; iter < 2; ++iter) {
+    MakeBuilder(options, pikc, &writable, &builder);
+    for (const auto& k : keys) {
+      builder->Add(k.Encode(), "val");
+    }
+
+    ASSERT_OK(builder->Finish());
+
+    FakeRandomeAccessFile readable(writable->contents());
+    TableProperties* props;
+    Status s =
+        ReadTableProperties(&readable, writable->contents().size(),
+                            magic_number, Env::Default(), nullptr, &props);
+    ASSERT_OK(s);
+
+    std::unique_ptr<TableProperties> props_guard(props);
+    auto user_collected = props->user_collected_properties;
+    uint64_t deleted = GetDeletedKeys(user_collected);
+    ASSERT_EQ(4u, deleted);
+
+    if (sanitized) {
+      uint32_t starts_with_A = 0;
+      Slice key(user_collected.at("Count"));
+      ASSERT_TRUE(GetVarint32(&key, &starts_with_A));
+      ASSERT_EQ(1u, starts_with_A);
+    }
+  }
+}
+}  // namespace
+
+TEST(TablePropertiesTest, InternalKeyPropertiesCollector) {
+  TestInternalKeyPropertiesCollector(
+      kBlockBasedTableMagicNumber,
+      true /* sanitize */,
+      std::make_shared<BlockBasedTableFactory>()
+  );
+  TestInternalKeyPropertiesCollector(
+      kBlockBasedTableMagicNumber,
+      true /* not sanitize */,
+      std::make_shared<BlockBasedTableFactory>()
+  );
+  TestInternalKeyPropertiesCollector(
+      kPlainTableMagicNumber,
+      false /* not sanitize */,
+      std::make_shared<PlainTableFactory>(8, 8, 0)
+  );
+}
+
+}  // namespace rocksdb
+
+int main(int argc, char** argv) {
+  return rocksdb::test::RunAllTests();
+}

db/tailing_iter.cc

@@ -0,0 +1,221 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+
+#ifndef ROCKSDB_LITE
+#include "db/tailing_iter.h"
+
+#include <string>
+#include <utility>
+#include <vector>
+#include "db/db_impl.h"
+#include "db/db_iter.h"
+#include "db/column_family.h"
+#include "rocksdb/env.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/slice_transform.h"
+#include "table/merger.h"
+
+namespace rocksdb {
+
+TailingIterator::TailingIterator(Env* const env, DBImpl* db,
+    const ReadOptions& read_options, ColumnFamilyData* cfd)
+    : env_(env),
+      db_(db),
+      read_options_(read_options),
+      cfd_(cfd),
+      super_version_(nullptr),
+      current_(nullptr),
+      status_(Status::InvalidArgument("Seek() not called on this iterator")) {}
+
+TailingIterator::~TailingIterator() {
+  Cleanup();
+}
+
+bool TailingIterator::Valid() const {
+  return current_ != nullptr;
+}
+
+void TailingIterator::SeekToFirst() {
+  if (!IsCurrentVersion()) {
+    CreateIterators();
+  }
+
+  mutable_->SeekToFirst();
+  immutable_->SeekToFirst();
+  UpdateCurrent();
+}
+
+void TailingIterator::Seek(const Slice& target) {
+  if (!IsCurrentVersion()) {
+    CreateIterators();
+  }
+
+  mutable_->Seek(target);
+
+  // We maintain the interval (prev_key_, immutable_->key()] such that there
+  // are no records with keys within that range in immutable_ other than
+  // immutable_->key(). Since immutable_ can't change in this version, we don't
+  // need to do a seek if 'target' belongs to that interval (i.e. immutable_ is
+  // already at the correct position)!
+  //
+  // If prefix seek is used and immutable_ is not valid, seek if target has a
+  // different prefix than prev_key.
+  //
+  // prev_key_ is updated by Next(). SeekImmutable() sets prev_key_ to
+  // 'target' -- in this case, prev_key_ is included in the interval, so
+  // prev_inclusive_ has to be set.
+
+  const Comparator* cmp = cfd_->user_comparator();
+  if (!is_prev_set_ || cmp->Compare(prev_key_, target) >= !is_prev_inclusive_ ||
+      (immutable_->Valid() && cmp->Compare(target, immutable_->key()) > 0) ||
+      (cfd_->options()->prefix_extractor != nullptr && !IsSamePrefix(target))) {
+    SeekImmutable(target);
+  }
+
+  UpdateCurrent();
+}
+
+void TailingIterator::Next() {
+  assert(Valid());
+
+  if (!IsCurrentVersion()) {
+    // save the current key, create new iterators and then seek
+    std::string current_key = key().ToString();
+    Slice key_slice(current_key.data(), current_key.size());
+
+    CreateIterators();
+    Seek(key_slice);
+
+    if (!Valid() || key().compare(key_slice) != 0) {
+      // record with current_key no longer exists
+      return;
+    }
+
+  } else if (current_ == immutable_.get()) {
+    // immutable iterator is advanced -- update prev_key_
+    prev_key_ = key().ToString();
+    is_prev_inclusive_ = false;
+    is_prev_set_ = true;
+  }
+
+  current_->Next();
+  UpdateCurrent();
+}
+
+Slice TailingIterator::key() const {
+  assert(Valid());
+  return current_->key();
+}
+
+Slice TailingIterator::value() const {
+  assert(Valid());
+  return current_->value();
+}
+
+Status TailingIterator::status() const {
+  if (!status_.ok()) {
+    return status_;
+  } else if (!mutable_->status().ok()) {
+    return mutable_->status();
+  } else {
+    return immutable_->status();
+  }
+}
+
+void TailingIterator::Prev() {
+  status_ = Status::NotSupported("This iterator doesn't support Prev()");
+}
+
+void TailingIterator::SeekToLast() {
+  status_ = Status::NotSupported("This iterator doesn't support SeekToLast()");
+}
+
+void TailingIterator::Cleanup() {
+  // Release old super version if necessary
+  mutable_.reset();
+  immutable_.reset();
+  if (super_version_ != nullptr && super_version_->Unref()) {
+    DBImpl::DeletionState deletion_state;
+    db_->mutex_.Lock();
+    super_version_->Cleanup();
+    db_->FindObsoleteFiles(deletion_state, false, true);
+    db_->mutex_.Unlock();
+    delete super_version_;
+    if (deletion_state.HaveSomethingToDelete()) {
+      db_->PurgeObsoleteFiles(deletion_state);
+    }
+  }
+}
+
+void TailingIterator::CreateIterators() {
+  Cleanup();
+  super_version_= cfd_->GetReferencedSuperVersion(&(db_->mutex_));
+
+  Iterator* mutable_iter = super_version_->mem->NewIterator(read_options_);
+  // create a DBIter that only uses memtable content; see NewIterator()
+  mutable_.reset(
+      NewDBIterator(env_, *cfd_->options(), cfd_->user_comparator(),
+                    mutable_iter, kMaxSequenceNumber));
+
+  std::vector<Iterator*> list;
+  super_version_->imm->AddIterators(read_options_, &list);
+  super_version_->current->AddIterators(
+      read_options_, *cfd_->soptions(), &list);
+  Iterator* immutable_iter =
+      NewMergingIterator(&cfd_->internal_comparator(), &list[0], list.size());
+
+  // create a DBIter that only uses memtable content; see NewIterator()
+  immutable_.reset(
+      NewDBIterator(env_, *cfd_->options(), cfd_->user_comparator(),
+                    immutable_iter, kMaxSequenceNumber));
+
+  current_ = nullptr;
+  is_prev_set_ = false;
+}
+
+void TailingIterator::UpdateCurrent() {
+  current_ = nullptr;
+
+  if (mutable_->Valid()) {
+    current_ = mutable_.get();
+  }
+  const Comparator* cmp = cfd_->user_comparator();
+  if (immutable_->Valid() &&
+      (current_ == nullptr ||
+       cmp->Compare(immutable_->key(), current_->key()) < 0)) {
+    current_ = immutable_.get();
+  }
+
+  if (!status_.ok()) {
+    // reset status that was set by Prev() or SeekToLast()
+    status_ = Status::OK();
+  }
+}
+
+bool TailingIterator::IsCurrentVersion() const {
+  return super_version_ != nullptr &&
+         super_version_->version_number == cfd_->GetSuperVersionNumber();
+}
+
+bool TailingIterator::IsSamePrefix(const Slice& target) const {
+  const SliceTransform* extractor = cfd_->options()->prefix_extractor.get();
+
+  assert(extractor);
+  assert(is_prev_set_);
+
+  return extractor->Transform(target)
+    .compare(extractor->Transform(prev_key_)) == 0;
+}
+
+void TailingIterator::SeekImmutable(const Slice& target) {
+  prev_key_ = target.ToString();
+  is_prev_inclusive_ = true;
+  is_prev_set_ = true;
+
+  immutable_->Seek(target);
+}
+
+}  // namespace rocksdb
+#endif  // ROCKSDB_LITE

db/tailing_iter.h

@@ -0,0 +1,97 @@
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+#pragma once
+
+#ifndef ROCKSDB_LITE
+
+#include <string>
+
+#include "rocksdb/db.h"
+#include "rocksdb/iterator.h"
+#include "rocksdb/options.h"
+
+namespace rocksdb {
+
+class DBImpl;
+class Env;
+struct SuperVersion;
+class ColumnFamilyData;
+
+/**
+ * TailingIterator is a special type of iterator that doesn't use an (implicit)
+ * snapshot. In other words, it can be used to read data that was added to the
+ * db after the iterator had been created.
+ *
+ * TailingIterator is optimized for sequential reading. It doesn't support
+ * Prev() and SeekToLast() operations.
+ */
+class TailingIterator : public Iterator {
+ public:
+  TailingIterator(Env* const env, DBImpl* db, const ReadOptions& read_options,
+                  ColumnFamilyData* cfd);
+  virtual ~TailingIterator();
+
+  virtual bool Valid() const override;
+  virtual void SeekToFirst() override;
+  virtual void SeekToLast() override;
+  virtual void Seek(const Slice& target) override;
+  virtual void Next() override;
+  virtual void Prev() override;
+  virtual Slice key() const override;
+  virtual Slice value() const override;
+  virtual Status status() const override;
+
+ private:
+  void Cleanup();
+
+  Env* const env_;
+  DBImpl* const db_;
+  const ReadOptions read_options_;
+  ColumnFamilyData* const cfd_;
+  SuperVersion* super_version_;
+
+  // TailingIterator merges the contents of the two iterators below (one using
+  // mutable memtable contents only, other over SSTs and immutable memtables).
+  // See DBIter::GetTailingIteratorPair().
+  std::unique_ptr<Iterator> mutable_;
+  std::unique_ptr<Iterator> immutable_;
+
+  // points to either mutable_ or immutable_
+  Iterator* current_;
+
+  // key that precedes immutable iterator's current key
+  std::string prev_key_;
+
+  // unless prev_set is true, prev_key/prev_head is not valid and shouldn't be
+  // used; reset by createIterators()
+  bool is_prev_set_;
+
+  // prev_key_ was set by SeekImmutable(), which means that the interval of
+  // keys covered by immutable_ is [prev_key_, current], i.e. it includes the
+  // left endpoint
+  bool is_prev_inclusive_;
+
+  // internal iterator status
+  Status status_;
+
+  // check if this iterator's version matches DB's version
+  bool IsCurrentVersion() const;
+
+  // check if SeekImmutable() is needed due to target having a different prefix
+  // than prev_key_ (used when in prefix seek mode)
+  bool IsSamePrefix(const Slice& target) const;
+
+  // creates mutable_ and immutable_ iterators and updates version_number_
+  void CreateIterators();
+
+  // set current_ to be one of the iterators with the smallest key
+  void UpdateCurrent();
+
+  // seek on immutable_ and update prev_key
+  void SeekImmutable(const Slice& target);
+};
+
+}  // namespace rocksdb
+#endif  // ROCKSDB_LITE