Summary:
- propagate lower-level read and merge failures through `GetContext` via `read_status`, so `Get` and `GetEntity` preserve the original error instead of synthesizing `Corruption` when blob-backed reads or merge resolution fail
- teach `GetMergeOperands` to resolve blob-backed default columns from wide-column entities, covering both the direct base-value path and the merge-plus-base path
- add regression coverage for blob-read IO errors during `Get`/`GetEntity` merge resolution and for `GetMergeOperands` on blob-backed wide-column entities
- fix the `DBFlushTest.MemPurgeCorrectLogNumberAndSSTFileCreation` test race by waiting for flush callbacks and cleaning up sync points
## Testing
- `make db_blob_basic_test -j14`
- `/usr/bin/perl -e 'alarm shift; exec ARGV' 60 ./db_blob_basic_test --gtest_filter='DBBlobBasicTest/DBBlobBasicIOErrorTest.GetBlob_IOError/*:DBBlobBasicTest/DBBlobBasicIOErrorTest.GetEntityMergeWithBlobBaseIOError/*'`
## Task
T265824017, T265415808
Pull Request resolved: https://github.com/facebook/rocksdb/pull/14640
Reviewed By: anand1976
Differential Revision: D101690700
Pulled By: xingbowang
fbshipit-source-id: 2b6fc357b37a01efa72a2d54dcff55be8992f42a
Summary:
Wide-column blob separation: lazy resolution through read, compaction, and write paths
Extend blob direct write to support wide-column entities (PutEntity), and add
lazy blob resolution for wide-column values across all read and compaction paths.
**Write path -- PutEntity blob separation:**
- BlobWriteBatchTransformer::PutEntityCF now extracts large column values
(>= min_blob_size) to blob files and serializes V2 entities with BlobIndex
references, matching the existing Put behavior.
- Add MaybePreprocessWideColumns() static helper to share blob extraction
logic between the WriteBatch transformer and the new PutEntity fast path.
- Add PutEntityFastPath() in DBImpl that preprocesses columns (sort, blob
extract, serialize) before calling WriteImpl, skipping the redundant
WriteBatch transformation pass. Trace batch preserves the original columns.
**Read path -- blob resolution for Get/MultiGet/Iterator:**
- GetContext::SaveValue resolves V2 entity blob columns eagerly: for
value (Get), resolves the default column's blob reference; for columns
(GetEntity), resolves all blob columns and re-serializes as V1.
- DBIter::SetValueAndColumnsFromEntity detects V2 entities, deserializes
with DeserializeV2, and eagerly resolves all blob columns via a new
ReadPathBlobResolver. Resolved values are cached in the resolver and
wide_columns_ Slices point into the cache, avoiding copies.
- Add ReadPathBlobResolver (new file) -- on-demand blob fetcher for the
read path with per-column caching, used by both DBIter and GetContext.
- BlobFetcher gains allow_write_path_fallback to read from in-flight
direct-write blob files not yet visible through Version (pre-flush reads).
- Memtable lookups for Get(key) on V2 entities with a blob default column
now return the blob index with is_blob_index=true, triggering the
existing BDW resolution in MaybeResolveWritePathValue.
- MaybeResolveWritePathValue (renamed from MaybeResolveDirectWriteBlobIndex)
now also resolves V2 entity blob columns for GetEntity/MultiGetEntity,
re-serializing as V1 after resolution.
**Compaction path -- filter, GC, and extraction:**
- CompactionIterator::InvokeFilterIfNeeded handles V2 entities: FilterV3
gets eagerly-resolved column values for backward compatibility; FilterV4
gets a CompactionBlobResolver for lazy on-demand resolution.
- Add CompactionFilter::FilterV4 with WideColumnBlobResolver* parameter
and SupportsFilterV4() opt-in. Default delegates to FilterV3.
- CompactionBlobResolver (new class) implements WideColumnBlobResolver
for the compaction path with stats tracking.
- ExtractLargeColumnValuesIfNeeded extracts inline columns to blob files
during compaction (entities without existing blob columns only).
- GarbageCollectEntityBlobsIfNeeded relocates blob values from old blob
files to new ones during compaction GC, with helpers FetchBlobsNeedingGC,
RelocateBlobValues, and SerializeEntityAfterGC.
- PrepareOutput unified entity deserialization: single DeserializeV2 call
reused by both filter and GC/extraction paths via entity_deserialized_
flag, avoiding redundant parsing.
**Merge path -- V2 entity base value resolution:**
- MergeHelper::MergeUntil, GetContext::MergeWithWideColumnBaseValue, and
DBIter::MergeWithWideColumnBaseValue resolve V2 blob columns before
calling TimedFullMerge, using ResolveEntityForMerge.
**Blob garbage accounting:**
- BlobGarbageMeter tracks blob file in/out flow for V2 entity blob
columns via ForEachBlobFileNumber, used for accurate GC decisions.
- FileMetaData::UpdateBoundaries tracks oldest_blob_file_number for
V2 entities, ensuring blob files referenced by entities are not
prematurely deleted.
**Serialization improvements:**
- WideColumnSerialization::SerializeV2Impl allocates serialized_blob_indices
only for actual blob columns (not all columns) and uses autovector for
name/value sizes.
- Add ForEachBlobFileNumber for lightweight blob file number extraction
without full deserialization.
- Add ResolveEntityForMerge helper for merge-path resolution.
- Add section-size validation in DeserializeV2Impl.
- Add empty blob index and column type validation.
- blob_column_resolver_util.h -- shared helpers (FindBlobColumn, FindInCache,
CacheInlinedBlob) used by both ReadPathBlobResolver and CompactionBlobResolver.
**Testing:**
- db_blob_direct_write_test: end-to-end PutEntity with BDW before/after flush,
verifying Get, GetEntity, MultiGetEntity, and Iterator.
- db_blob_index_test: ~1550 lines covering V2 entity blob resolution through
Get, GetEntity, MultiGet, Iterator, compaction filter (V3 compat and V4 lazy),
merge with blob base, and compaction GC/extraction.
- compaction_iterator_test: ~950 lines testing entity blob GC, extraction,
filter interaction, and combined GC+filter scenarios.
- db_wide_basic_test: ~1200 lines for wide-column lazy blob resolution through
all read paths plus compaction round-trips.
- db_open_with_config_test: ~450 lines for BDW entity config validation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/14386
Reviewed By: anand1976
Differential Revision: D99739701
Pulled By: xingbowang
fbshipit-source-id: 6badd89b577f3054802eaaa654738468efb9dbdb
Summary:
Introduce a new V2 serialization format for wide column entities that supports storing individual column values in blob files. The V2 format adds a column type section that marks each column as either inline or blob-index, enabling per-column blob storage for large values.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/14314
Reviewed By: pdillinger
Differential Revision: D92832066
Pulled By: xingbowang
fbshipit-source-id: 13c24347e1f481a059d67eef987d2d2b184b4a51
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/13168
The patch moves `WideColumnSerialization::Find` to `WideColumnsHelper` to facilitate reuse in non-serialization-related contexts. It also generalizes the method to take a range of iterators, and templatizes it on the iterator type to enable using it with both `const` and non-`const` iterators. Finally, it adds an assertion to ensure the method is called with a properly sorted range, which is a precondition for binary search.
Reviewed By: jaykorean
Differential Revision: D66602558
fbshipit-source-id: 841a885af31e183edeb7e3314167c55f8ed53ff1
Summary:
The patch makes it possible to provide the value of the default column
separately when calling `WideColumnSerialization::Serialize`. This eliminates
the need to construct a new `WideColumns` vector in certain cases
(for example, it will come in handy when implementing `Merge`).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10839
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D40561448
Pulled By: ltamasi
fbshipit-source-id: 69becdd510e6a83ab1feb956c12772110e1040d6
Summary:
The patch adds support for wide-column entities to the existing query
APIs (`Get`, `MultiGet`, and iterator). Namely, when during a query a
wide-column entity is encountered, we will return the value of the default
(anonymous) column as the result. Later, we plan to add wide-column
specific query APIs which will enable retrieving entire wide-column entities
or a subset of their columns.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10483
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D38441881
Pulled By: ltamasi
fbshipit-source-id: 6444e79a31aff2470e866698e3a97985bc2b3543
Summary:
The patch adds some low-level logic that can be used to serialize/deserialize
a sorted vector of wide columns to/from a simple binary searchable string
representation. Currently, there is no user-facing API; this will be implemented in
subsequent stages.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9915
Test Plan: `make check`
Reviewed By: siying
Differential Revision: D35978076
Pulled By: ltamasi
fbshipit-source-id: 33f5f6628ec3bcd8c8beab363b1978ac047a8788
Xingbo Wang