Bump version to 6.1.2

Summary:
Flush/compaction use `MergeUntil` which has a special code path to
handle a merge ending with a non-`Merge` point key. In particular if
that key is a `Put` we forgot to check whether it is covered by a range
tombstone. If it is covered then we must not include it in the following call
to `TimedFullMerge`.

Fixes #5392.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5406

Differential Revision: D15611144

Pulled By: sagar0

fbshipit-source-id: ba6a7863ca2d043f591de78fd0c4f4561f0c500e

HISTORY.md

@@ -1,6 +1,9 @@
 # Rocksdb Change Log
+## 6.1.2 (6/4/2019)
+### Bug Fixes
+* Fix flush's/compaction's merge processing logic which allowed `Put`s covered by range tombstones to reappear. Note `Put`s may exist even if the user only ever called `Merge()` due to an internal conversion during compaction to the bottommost level.
 
-### Unreleased
+## 6.1.1 (4/9/2019)
 ### New Features
 * When reading from option file/string/map, customized comparators and/or merge operators can be filled according to object registry.
 ### Public API Change

db/db_range_del_test.cc

@@ -490,6 +490,30 @@ TEST_F(DBRangeDelTest, CompactionRemovesCoveredMergeOperands) {
   ASSERT_EQ(expected, actual);
 }
 
+TEST_F(DBRangeDelTest, PutDeleteRangeMergeFlush) {
+  // Test the sequence of operations: (1) Put, (2) DeleteRange, (3) Merge, (4)
+  // Flush. The `CompactionIterator` previously had a bug where we forgot to
+  // check for covering range tombstones when processing the (1) Put, causing
+  // it to reappear after the flush.
+  Options opts = CurrentOptions();
+  opts.merge_operator = MergeOperators::CreateUInt64AddOperator();
+  Reopen(opts);
+
+  std::string val;
+  PutFixed64(&val, 1);
+  ASSERT_OK(db_->Put(WriteOptions(), "key", val));
+  ASSERT_OK(db_->DeleteRange(WriteOptions(), db_->DefaultColumnFamily(),
+                             "key", "key_"));
+  ASSERT_OK(db_->Merge(WriteOptions(), "key", val));
+  ASSERT_OK(db_->Flush(FlushOptions()));
+
+  ReadOptions read_opts;
+  std::string expected, actual;
+  ASSERT_OK(db_->Get(read_opts, "key", &actual));
+  PutFixed64(&expected, 1);
+  ASSERT_EQ(expected, actual);
+}
+
 // NumTableFilesAtLevel() is not supported in ROCKSDB_LITE
 #ifndef ROCKSDB_LITE
 TEST_F(DBRangeDelTest, ObsoleteTombstoneCleanup) {

db/db_test2.cc

@@ -3661,6 +3661,48 @@ TEST_F(DBTest2, MultiDBParallelOpenTest) {
 }
 #endif  // OS_WIN
 
+namespace {
+class DummyOldStats : public Statistics {
+ public:
+  uint64_t getTickerCount(uint32_t /*ticker_type*/) const override { return 0; }
+  void recordTick(uint32_t /* ticker_type */, uint64_t /* count */) override {
+    num_rt++;
+  }
+  void setTickerCount(uint32_t /*ticker_type*/, uint64_t /*count*/) override {}
+  uint64_t getAndResetTickerCount(uint32_t /*ticker_type*/) override {
+    return 0;
+  }
+  void measureTime(uint32_t /*histogram_type*/, uint64_t /*count*/) override {
+    num_mt++;
+  }
+  void histogramData(uint32_t /*histogram_type*/,
+                     rocksdb::HistogramData* const /*data*/) const override {}
+  std::string getHistogramString(uint32_t /*type*/) const override {
+    return "";
+  }
+  bool HistEnabledForType(uint32_t /*type*/) const override { return false; }
+  std::string ToString() const override { return ""; }
+  int num_rt = 0;
+  int num_mt = 0;
+};
+}  // namespace
+
+TEST_F(DBTest2, OldStatsInterface) {
+  DummyOldStats* dos = new DummyOldStats();
+  std::shared_ptr<Statistics> stats(dos);
+  Options options = CurrentOptions();
+  options.create_if_missing = true;
+  options.statistics = stats;
+  Reopen(options);
+
+  Put("foo", "bar");
+  ASSERT_EQ("bar", Get("foo"));
+  ASSERT_OK(Flush());
+  ASSERT_EQ("bar", Get("foo"));
+
+  ASSERT_GT(dos->num_rt, 0);
+  ASSERT_GT(dos->num_mt, 0);
+}
 }  // namespace rocksdb
 
 int main(int argc, char** argv) {

db/merge_helper.cc

@@ -201,7 +201,15 @@ Status MergeHelper::MergeUntil(InternalIterator* iter,
       // want. Also if we're in compaction and it's a put, it would be nice to
       // run compaction filter on it.
       const Slice val = iter->value();
-      const Slice* val_ptr = (kTypeValue == ikey.type) ? &val : nullptr;
+      const Slice* val_ptr;
+      if (kTypeValue == ikey.type &&
+          (range_del_agg == nullptr ||
+           !range_del_agg->ShouldDelete(
+               ikey, RangeDelPositioningMode::kForwardTraversal))) {
+        val_ptr = &val;
+      } else {
+        val_ptr = nullptr;
+      }
       std::string merge_result;
       s = TimedFullMerge(user_merge_operator_, ikey.user_key, val_ptr,
                          merge_context_.GetOperands(), &merge_result, logger_,

db/version_set.cc

@@ -2235,7 +2235,7 @@ void VersionStorageInfo::GetOverlappingInputsRangeBinarySearch(
   // If there were no overlapping files, return immediately.
   if (!foundOverlap) {
     if (next_smallest) {
-      next_smallest = nullptr;
+      *next_smallest = nullptr;
     }
     return;
   }

include/rocksdb/version.h

@@ -6,7 +6,7 @@
 
 #define ROCKSDB_MAJOR 6
 #define ROCKSDB_MINOR 1
-#define ROCKSDB_PATCH 0
+#define ROCKSDB_PATCH 2
 
 // Do not use these. We made the mistake of declaring macros starting with
 // double underscore. Now we have to live with our choice. We'll deprecate these

monitoring/statistics.h

@@ -53,6 +53,13 @@ class StatisticsImpl : public Statistics {
   virtual void setTickerCount(uint32_t ticker_type, uint64_t count) override;
   virtual uint64_t getAndResetTickerCount(uint32_t ticker_type) override;
   virtual void recordTick(uint32_t ticker_type, uint64_t count) override;
+  // The function is implemented for now for backward compatibility reason.
+  // In case a user explictly calls it, for example, they may have a wrapped
+  // Statistics object, passing the call to recordTick() into here, nothing
+  // will break.
+  void measureTime(uint32_t histogramType, uint64_t time) override {
+    recordInHistogram(histogramType, time);
+  }
   virtual void recordInHistogram(uint32_t histogram_type,
                                  uint64_t value) override;
 

table/iterator.cc

@@ -157,6 +157,8 @@ class EmptyInternalIterator : public InternalIteratorBase<TValue> {
 };
 }  // namespace
 
+Iterator* NewEmptyIterator() { return new EmptyIterator(Status::OK()); }
+
 Iterator* NewErrorIterator(const Status& status) {
   return new EmptyIterator(status);
 }