Summary:
I did another pass through running CI jobs. It is uncommon now to see
`db_stress` stuck in the setup phase but still happen.
One reason was repeatedly reading/verifying checksum on filter blocks when
`-cache_index_and_filter_blocks=1` and `-cache_size=1048576`. To address
that I increased the cache size.
Another reason was having a WAL with many range tombstones and every
`db_stress` run using `-avoid_flush_during_recovery=1` (in that
scenario, the setup phase spent too much CPU in
`rocksdb::MemTable::NewRangeTombstoneIteratorInternal()`). To address
that I fixed the `-avoid_flush_during_recovery` setting so it is
reevaluated for every `db_stress` run.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9483
Reviewed By: riversand963
Differential Revision: D33922929
Pulled By: ajkr
fbshipit-source-id: 0a298ec7c4df6f6b44620233996047a2dc7ee5f3
Summary:
**Context:**
Running the new test `DBMergeOperandTest.MergeOperandReadAfterFreeBug` prior to this fix surfaces the read-after-free bug of PinSef() as below:
```
READ of size 8 at 0x60400002529d thread T0
https://github.com/facebook/rocksdb/issues/5 0x7f199a in rocksdb::PinnableSlice::PinSelf(rocksdb::Slice const&) include/rocksdb/slice.h:171
https://github.com/facebook/rocksdb/issues/6 0x7f199a in rocksdb::DBImpl::GetImpl(rocksdb::ReadOptions const&, rocksdb::Slice const&, rocksdb::DBImpl::GetImplOptions&) db/db_impl/db_impl.cc:1919
https://github.com/facebook/rocksdb/issues/7 0x540d63 in rocksdb::DBImpl::GetMergeOperands(rocksdb::ReadOptions const&, rocksdb::ColumnFamilyHandle*, rocksdb::Slice const&, rocksdb::PinnableSlice*, rocksdb::GetMergeOperandsOptions*, int*) db/db_impl/db_impl.h:203
freed by thread T0 here:
https://github.com/facebook/rocksdb/issues/3 0x1191399 in rocksdb::cache_entry_roles_detail::RegisteredDeleter<rocksdb::Block, (rocksdb::CacheEntryRole)0>::Delete(rocksdb::Slice const&, void*) cache/cache_entry_roles.h:99
https://github.com/facebook/rocksdb/issues/4 0x719348 in rocksdb::LRUHandle::Free() cache/lru_cache.h:205
https://github.com/facebook/rocksdb/issues/5 0x71047f in rocksdb::LRUCacheShard::Release(rocksdb::Cache::Handle*, bool) cache/lru_cache.cc:547
https://github.com/facebook/rocksdb/issues/6 0xa78f0a in rocksdb::Cleanable::DoCleanup() include/rocksdb/cleanable.h:60
https://github.com/facebook/rocksdb/issues/7 0xa78f0a in rocksdb::Cleanable::Reset() include/rocksdb/cleanable.h:38
https://github.com/facebook/rocksdb/issues/8 0xa78f0a in rocksdb::PinnedIteratorsManager::ReleasePinnedData() db/pinned_iterators_manager.h:71
https://github.com/facebook/rocksdb/issues/9 0xd0c21b in rocksdb::PinnedIteratorsManager::~PinnedIteratorsManager() db/pinned_iterators_manager.h:24
https://github.com/facebook/rocksdb/issues/10 0xd0c21b in rocksdb::Version::Get(rocksdb::ReadOptions const&, rocksdb::LookupKey const&, rocksdb::PinnableSlice*, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >*, rocksdb::Status*, rocksdb::MergeContext*, unsigned long*, bool*, bool*, unsigned long*, rocksdb::ReadCallback*, bool*, bool) db/pinned_iterators_manager.h:22
https://github.com/facebook/rocksdb/issues/11 0x7f0fdf in rocksdb::DBImpl::GetImpl(rocksdb::ReadOptions const&, rocksdb::Slice const&, rocksdb::DBImpl::GetImplOptions&) db/db_impl/db_impl.cc:1886
https://github.com/facebook/rocksdb/issues/12 0x540d63 in rocksdb::DBImpl::GetMergeOperands(rocksdb::ReadOptions const&, rocksdb::ColumnFamilyHandle*, rocksdb::Slice const&, rocksdb::PinnableSlice*, rocksdb::GetMergeOperandsOptions*, int*) db/db_impl/db_impl.h:203
previously allocated by thread T0 here:
https://github.com/facebook/rocksdb/issues/1 0x1239896 in rocksdb::AllocateBlock(unsigned long, **rocksdb::MemoryAllocator*)** memory/memory_allocator.h:35
https://github.com/facebook/rocksdb/issues/2 0x1239896 in rocksdb::BlockFetcher::CopyBufferToHeapBuf() table/block_fetcher.cc:171
https://github.com/facebook/rocksdb/issues/3 0x1239896 in rocksdb::BlockFetcher::GetBlockContents() table/block_fetcher.cc:206
https://github.com/facebook/rocksdb/issues/4 0x122eae5 in rocksdb::BlockFetcher::ReadBlockContents() table/block_fetcher.cc:325
https://github.com/facebook/rocksdb/issues/5 0x11b1f45 in rocksdb::Status rocksdb::BlockBasedTable::MaybeReadBlockAndLoadToCache<rocksdb::Block>(rocksdb::FilePrefetchBuffer*, rocksdb::ReadOptions const&, rocksdb::BlockHandle const&, rocksdb::UncompressionDict const&, bool, rocksdb::CachableEntry<rocksdb::Block>*, rocksdb::BlockType, rocksdb::GetContext*, rocksdb::BlockCacheLookupContext*, rocksdb::BlockContents*) const table/block_based/block_based_table_reader.cc:1503
```
Here is the analysis:
- We have [PinnedIteratorsManager](https://github.com/facebook/rocksdb/blob/6.28.fb/db/version_set.cc#L1980) with `Cleanable` capability in our `Version::Get()` path. It's responsible for managing the life-time of pinned iterator and invoking registered cleanup functions during its own destruction.
- For example in case above, the merge operands's clean-up gets associated with this manger in [GetContext::push_operand](https://github.com/facebook/rocksdb/blob/6.28.fb/table/get_context.cc#L405). During PinnedIteratorsManager's [destruction](https://github.com/facebook/rocksdb/blob/6.28.fb/db/pinned_iterators_manager.h#L67), the release function associated with those merge operand data is invoked.
**And that's what we see in "freed by thread T955 here" in ASAN.**
- Bug 🐛: `PinnedIteratorsManager` is local to `Version::Get()` while the data of merge operands need to outlive `Version::Get` and stay till they get [PinSelf()](https://github.com/facebook/rocksdb/blob/6.28.fb/db/db_impl/db_impl.cc#L1905), **which is the read-after-free in ASAN.**
- This bug is likely to be an overlook of `PinnedIteratorsManager` when developing the API `DB::GetMergeOperands` cuz the current logic works fine with the existing case of getting the *merged value* where the operands do not need to live that long.
- This bug was not surfaced much (even in its unit test) due to the release function associated with the merge operands (which are actually blocks put in cache as you can see in `BlockBasedTable::MaybeReadBlockAndLoadToCache` **in "previously allocated by" in ASAN report**) is a cache entry deleter.
The deleter will call `Cache::Release()` which, for LRU cache, won't immediately deallocate the block based on LRU policy [unless the cache is full or being instructed to force erase](https://github.com/facebook/rocksdb/blob/6.28.fb/cache/lru_cache.cc#L521-L531)
- `DBMergeOperandTest.MergeOperandReadAfterFreeBug` makes the cache extremely small to force cache full.
**Summary:**
- Fix the bug by align `PinnedIteratorsManager`'s lifetime with the merge operands
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9507
Test Plan:
- New test `DBMergeOperandTest.MergeOperandReadAfterFreeBug`
- db bench on read path
- Setup (LSM tree with several levels, cache the whole db to avoid read IO, warm cache with readseq to avoid read IO): `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks="fillrandom,readseq -num=1000000 -cache_size=100000000 -write_buffer_size=10000 -statistics=1 -max_bytes_for_level_base=10000 -level0_file_num_compaction_trigger=1``TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks="readrandom" -num=1000000 -cache_size=100000000 `
- Actual command run (run 20-run for 20 times and then average the 20-run's average micros/op)
- `for j in {1..20}; do (for i in {1..20}; do rm -rf /dev/shm/rocksdb/ && TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks="fillrandom,readseq,readrandom" -num=1000000 -cache_size=100000000 -write_buffer_size=10000 -statistics=1 -max_bytes_for_level_base=10000 -level0_file_num_compaction_trigger=1 | egrep 'readrandom'; done > rr_output_pre.txt && (awk '{sum+=$3; sum_sqrt+=$3^2}END{print sum/20, sqrt(sum_sqrt/20-(sum/20)^2)}' rr_output_pre.txt) >> rr_output_pre_2.txt); done`
- **Result: Pre-change: 3.79193 micros/op; Post-change: 3.79528 micros/op (+0.09%)**
(pre-change)sorted avg micros/op of each 20-run | std of micros/op of each 20-run | (post-change) sorted avg micros/op of each 20-run | std of micros/op of each 20-run
-- | -- | -- | --
3.58355 | 0.265209 | 3.48715 | 0.382076
3.58845 | 0.519927 | 3.5832 | 0.382726
3.66415 | 0.452097 | 3.677 | 0.563831
3.68495 | 0.430897 | 3.68405 | 0.495355
3.70295 | 0.482893 | 3.68465 | 0.431438
3.719 | 0.463806 | 3.71945 | 0.457157
3.7393 | 0.453423 | 3.72795 | 0.538604
3.7806 | 0.527613 | 3.75075 | 0.444509
3.7817 | 0.426704 | 3.7683 | 0.468065
3.809 | 0.381033 | 3.8086 | 0.557378
3.80985 | 0.466011 | 3.81805 | 0.524833
3.8165 | 0.500351 | 3.83405 | 0.529339
3.8479 | 0.430326 | 3.86285 | 0.44831
3.85125 | 0.434108 | 3.8717 | 0.544098
3.8556 | 0.524602 | 3.895 | 0.411679
3.8656 | 0.476383 | 3.90965 | 0.566636
3.8911 | 0.488477 | 3.92735 | 0.608038
3.898 | 0.493978 | 3.9439 | 0.524511
3.97235 | 0.515008 | 3.9623 | 0.477416
3.9768 | 0.519993 | 3.98965 | 0.521481
- CI
Reviewed By: ajkr
Differential Revision: D34030519
Pulled By: hx235
fbshipit-source-id: a99ac585c11704c5ed93af033cb29ba0a7b16ae8
Summary:
After https://github.com/facebook/rocksdb/issues/9515 added a unique_ptr to Status, we see some
warnings-as-error in some internal builds like this:
```
stderr: rocksdb/src/db/compaction/compaction_job.cc:2839:7: error:
offset of on non-standard-layout type 'struct CompactionServiceResult'
[-Werror,-Winvalid-offsetof]
{offsetof(struct CompactionServiceResult, status),
^ ~~~~~~
```
I see three potential solutions to resolving this:
* Expand our use of an idiom that works around the warning (see offset_of
functions removed in this change, inspired by
https://gist.github.com/graphitemaster/494f21190bb2c63c5516) However,
this construction is invoking undefined behavior that assumes consistent
layout with no compiler-introduced indirection. A compiler incompatible
with our assumptions will likely compile the code and exhibit undefined
behavior.
* Migrate to something in place of offset, like a function mapping
CompactionServiceResult* to Status* (for the `status` field). This might
be required in the long term.
* **Selected:** Use our new C++17 dependency to use offsetof in a well-defined way
when the compiler allows it. From a comment on
https://gist.github.com/graphitemaster/494f21190bb2c63c5516:
> A final note: in C++17, offsetof is conditionally supported, which
> means that you can use it on any type (not just standard layout
> types) and the compiler will error if it can't compile it correctly.
> That appears to be the best option if you can live with C++17 and
> don't need constexpr support.
The C++17 semantics are confirmed on
https://en.cppreference.com/w/cpp/types/offsetof, so we can suppress the
warning as long as we accept that we might run into a compiler that
rejects the code, and at that point we will find a solution, such as
the more intrusive "migrate" solution above.
Although this is currently only showing in our buck build, it will
surely show up also with make and cmake, so I have updated those
configurations as well.
Also in the buck build, -Wno-expansion-to-defined does not appear to be
needed anymore (both current compiler configurations) so I
removed it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9563
Test Plan: Tried out buck builds with both current compiler configurations
Reviewed By: riversand963
Differential Revision: D34220931
Pulled By: pdillinger
fbshipit-source-id: d39436008259bd1eaaa87c77be69fb2a5b559e1f
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9562
With per-transaction `read_timestamp_`, it is possible to perform transaction validation after
locking a key in addition to sequence-based validation. Specifically, if a transaction has a
read_timestamp, then we perform timestamp-based validation as well after the key is locked
via `GetForUpdate()`. This is to make sure that no other transaction has modified the key and
committed successfully since the read timestamp (but before the locking operation) which
represents a consistent view of the database.
Reviewed By: ltamasi
Differential Revision: D31822034
fbshipit-source-id: c6f1828b7fc23e4f85e2d1ed73ff51464a058d91
Summary:
* Fix LIB_MODE=shared for Meta-internal builds (use PIC libraries
appropriately)
* Fix gnu_parallel to recognize CircleCI and Travis builds as not
connected to a terminal (was previously relying on the
`| cat_ignore_eagain` stuff for Ubuntu 16). This problem could cause
timeouts that should be 10m to balloon to 5h.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9553
Test Plan: manual and CI
Reviewed By: jay-zhuang
Differential Revision: D34182886
Pulled By: pdillinger
fbshipit-source-id: e95fd8002d94c8dc414bae1975e4fd348589f2b5
Summary:
Transaction multiGet convert to list-based.
RocksDB Java (non-transactional) has multiGetAsList() methods to expose multiGet(). These return a list of results. These methods replaced multiGet() methods returning an array of results, which were deprecated in Rocks 6 and are being removed in Rocks 7.
The transactional API still presents multiGet() methods returning arrays, so in Rocks 7 we replace these with multiGetAsList()methods and deprecate the multiGet() methods.
This does not require any changes to the supporting JNI/C++ code, only to the wrappers which present the Java API.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9522
Reviewed By: mrambacher
Differential Revision: D34114373
Pulled By: jay-zhuang
fbshipit-source-id: cb22d6095934d951b6aee4aed3e07923d3c18007
Summary:
This change removes the ability to configure the deprecated,
inefficient block-based filter in the public API. Options that would
have enabled it now use "full" (and optionally partitioned) filters.
Existing block-based filters can still be read and used, and a "back
door" way to build them still exists, for testing and in case of trouble.
About the only way this removal would cause an issue for users is if
temporary memory for filter construction greatly increases. In
HISTORY.md we suggest a few possible mitigations: partitioned filters,
smaller SST files, or setting reserve_table_builder_memory=true.
Or users who have customized a FilterPolicy using the
CreateFilter/KeyMayMatch mechanism removed in https://github.com/facebook/rocksdb/issues/9501 will have to upgrade
their code. (It's long past time for people to move to the new
builder/reader customization interface.)
This change also introduces some internal-use-only configuration strings
for testing specific filter implementations while bypassing some
compatibility / intelligence logic. This is intended to hint at a path
toward making FilterPolicy Customizable, but it also gives us a "back
door" way to configure block-based filter.
Aside: updated db_bench so that -readonly implies -use_existing_db
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9535
Test Plan:
Unit tests updated. Specifically,
* BlockBasedTableTest.BlockReadCountTest is tweaked to validate the back
door configuration interface and ignoring of `use_block_based_builder`.
* BlockBasedTableTest.TracingGetTest is migrated from testing
block-based filter access pattern to full filter access patter, by
re-ordering some things.
* Options test (pretty self-explanatory)
Performance test - create with `./db_bench -db=/dev/shm/rocksdb1 -bloom_bits=10 -cache_index_and_filter_blocks=1 -benchmarks=fillrandom -num=10000000 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0` with and without `-use_block_based_filter`, which creates a DB with 21 SST files in L0. Read with `./db_bench -db=/dev/shm/rocksdb1 -readonly -bloom_bits=10 -cache_index_and_filter_blocks=1 -benchmarks=readrandom -num=10000000 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -duration=30`
Without -use_block_based_filter: readrandom 464 ops/sec, 689280 KB DB
With -use_block_based_filter: readrandom 169 ops/sec, 690996 KB DB
No consistent difference with fillrandom
Reviewed By: jay-zhuang
Differential Revision: D34153871
Pulled By: pdillinger
fbshipit-source-id: 31f4a933c542f8f09aca47fa64aec67832a69738
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9537
Add `Transaction::SetReadTimestampForValidation()` and
`Transaction::SetCommitTimestamp()` APIs with default implementation
returning `Status::NotSupported()`. Currently, calling these two APIs do not
have any effect.
Also add checks to `PessimisticTransactionDB`
to enforce that column families in the same db either
- disable user-defined timestamp
- enable 64-bit timestamp
Just to clarify, a `PessimisticTransactionDB` can have some column families without
timestamps as well as column families that enable timestamp.
Each `PessimisticTransaction` can have two optional timestamps, `read_timestamp_`
used for additional validation and `commit_timestamp_` which denotes when the transaction commits.
For now, we are going to support `WriteCommittedTxn` (in a series of subsequent PRs)
Once set, we do not allow decreasing `read_timestamp_`. The `commit_timestamp_` must be
greater than `read_timestamp_` for each transaction and must be set before commit, unless
the transaction does not involve any column family that enables user-defined timestamp.
TransactionDB builds on top of RocksDB core `DB` layer. Though `DB` layer assumes
that user-defined timestamps are byte arrays, `TransactionDB` uses uint64_t to store
timestamps. When they are passed down, they are still interpreted as
byte-arrays by `DB`.
Reviewed By: ltamasi
Differential Revision: D31567959
fbshipit-source-id: b0b6b69acab5d8e340cf174f33e8b09f1c3d3502
Summary:
This change should guarantee that the default ObjectLibrary/Registry are long-lived and not destroyed while the process is running. This will prevent some issues of them being referenced after they were destroyed via the static destruction.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9464
Reviewed By: pdillinger
Differential Revision: D33849876
Pulled By: mrambacher
fbshipit-source-id: 7a69177d7c58c81be293fc7ef8e600d47ddbc14b
Summary:
When tests are run with TMPD, c_test may fail because TMPD
is not created by the test. It results in IO error: No such file
or directory: While mkdir if missing:
/tmp/rocksdb_test_tmp/rocksdb_c_test-0: No such file or directory
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9547
Test Plan:
make -j32 c_test;
TEST_TMPDIR=/tmp/rocksdb_test ./c_test
Reviewed By: riversand963
Differential Revision: D34173298
Pulled By: akankshamahajan15
fbshipit-source-id: 5b5a01f5b842c2487b05b0708c8e9532241db7f8
Summary:
We had a bug in `VersionStorageInfo::ComputeFilesMarkedForForcedBlobGC`
related to the edge case where all blob files are part of the "oldest batch",
i.e. where only the very oldest file has any linked SSTs. (See https://github.com/facebook/rocksdb/issues/9542)
This PR tries to make the logic in this method clearer and also adds a unit test
for the problematic case.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9548
Test Plan: `make check`
Reviewed By: akankshamahajan15
Differential Revision: D34158959
Pulled By: ltamasi
fbshipit-source-id: fbab6d749c569728382aa04f7b7c60c92cca7650
Summary:
This fix addresses https://github.com/facebook/rocksdb/issues/9299.
If attempting to create a new object via the ObjectRegistry and a factory is not found, the ObjectRegistry will return a "NotSupported" status. This is the same behavior as previously.
If the factory is found but could not successfully create the object, an "InvalidArgument" status is returned. If the factory returned a reason why (in the errmsg), this message will be in the returned status.
In practice, there are two options in the ConfigOptions that control how these errors are propagated:
- If "ignore_unknown_options=true", then both InvalidArgument and NotSupported status codes will be swallowed internally. Both cases will return success
- If "ignore_unsupported_options=true", then having no factory will return success but a failing factory will return an error
- If both options are false, both cases (no and failing factory) will return errors.
In practice this likely only changes Customizable that may be partially available. For example, the JEMallocMemoryAllocator is a built-in allocator that is registered with the system but may not be compiled in. In this case, the status code for this allocator changed from NotSupported("JEMalloc not available") to InvalidArgumen("JEMalloc not available"). Other Customizable builtins/plugins would have the same semantics.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9333
Reviewed By: pdillinger
Differential Revision: D33517681
Pulled By: mrambacher
fbshipit-source-id: 8033052d4a4a7b88c2d9f90147b1b4467e51f6fd
Summary:
Extend the periodic statistics in the info log with the total amount of garbage
in blob files and the space amplification pertaining to blob files, where the
latter is defined as `total_blob_file_size / (total_blob_file_size - total_blob_garbage_size)`.
Also expose the space amp via the `rocksdb.blob-stats` DB property.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9538
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D34126855
Pulled By: ltamasi
fbshipit-source-id: 3153e7a0fe0eca440322db273f4deaabaccc51b2
Summary:
Fixes a bug introduced in https://github.com/facebook/rocksdb/issues/9526 where we index one position past the
end of a `vector`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9542
Test Plan:
`make asan_check`
Will add a unit test in a separate PR.
Reviewed By: akankshamahajan15
Differential Revision: D34145825
Pulled By: ltamasi
fbshipit-source-id: 4e87c948407dee489d669a3e41f59e2fcc1228d8
Summary:
**Context:**
`EventListenerTest.MultiCF` occasionally failed on TSAN data race as below:
```
WARNING: ThreadSanitizer: data race (pid=2047633)
Read of size 8 at 0x7b6000001440 by main thread:
#0 std::vector<rocksdb::DB*, std::allocator<rocksdb::DB*> >::size() const /usr/bin/../lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/stl_vector.h:916:40 (listener_test+0x52337c)
https://github.com/facebook/rocksdb/issues/1 rocksdb::EventListenerTest_MultiCF_Test::TestBody() /home/circleci/project/db/listener_test.cc:384:7 (listener_test+0x52337c)
Previous write of size 8 at 0x7b6000001440 by thread T2:
#0 void std::vector<rocksdb::DB*, std::allocator<rocksdb::DB*> >::_M_realloc_insert<rocksdb::DB* const&>(__gnu_cxx::__normal_iterator<rocksdb::DB**, std::vector<rocksdb::DB*, std::allocator<rocksdb::DB*> > >, rocksdb::DB* const&) /usr/bin/../lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/vector.tcc:503:31 (listener_test+0x550654)
https://github.com/facebook/rocksdb/issues/1 std::vector<rocksdb::DB*, std::allocator<rocksdb::DB*> >::push_back(rocksdb::DB* const&) /usr/bin/../lib/gcc/x86_64-linux-gnu/9/../../../../include/c++/9/bits/stl_vector.h:1195:4 (listener_test+0x550654)
https://github.com/facebook/rocksdb/issues/2 rocksdb::TestFlushListener::OnFlushCompleted(rocksdb::DB*, rocksdb::FlushJobInfo const&) /home/circleci/project/db/listener_test.cc:255:18 (listener_test+0x550654)
```
After investigation, it is due to the following:
(1) `ASSERT_OK(Flush(i));` before the read `std::vector::size()` is supposed to be [blocked on `DB::Impl::bg_cv_` for memtable flush to finish](320d9a8e8a/db/db_impl/db_impl_compaction_flush.cc (L2319)) and get signaled [at the end of background flush ](320d9a8e8a/db/db_impl/db_impl_compaction_flush.cc (L2830)), which happens after the write `std::vector::push_back()` . So the sequence of execution should have been synchronized as `call flush() -> write -> return from flush() -> read` and would not cause any TSAN data race.
- The subsequent `ASSERT_OK(dbfull()->TEST_WaitForFlushMemTable());` serves a similar purpose based on [the previous attempt to deflake the test.](https://github.com/facebook/rocksdb/pull/9084)
(2) However, there are multiple places in the code can signal this `DB::Impl::bg_cv_` and mistakenly wake up `ASSERT_OK(Flush(i));` (or `ASSERT_OK(dbfull()->TEST_WaitForFlushMemTable());`) too early (and with the lock available to them), resulting in non-synchronized read and write thus a TSAN data race.
- Reproduced by the following, suggested by ajkr:
```
diff --git a/db/db_impl/db_impl_compaction_flush.cc b/db/db_impl/db_impl_compaction_flush.cc
index 4ff87c1e4..52492e9cf 100644
--- a/db/db_impl/db_impl_compaction_flush.cc
+++ b/db/db_impl/db_impl_compaction_flush.cc
@@ -22,7 +22,7 @@
#include "test_util/sync_point.h"
#include "util/cast_util.h"
#include "util/concurrent_task_limiter_impl.h"
namespace ROCKSDB_NAMESPACE {
bool DBImpl::EnoughRoomForCompaction(
@@ -855,6 +855,7 @@ void DBImpl::NotifyOnFlushCompleted(
mutable_cf_options.level0_stop_writes_trigger);
// release lock while notifying events
mutex_.Unlock();
+ bg_cv_.SignalAll();
```
**Summary:**
- Added synchornization between read and write by ` ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->LoadDependency()` mechanism
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9528
Test Plan:
`./listener_test --gtest_filter=EventListenerTest.MultiCF --gtest_repeat=10`
- pre-fix:
```
Repeating all tests (iteration 3)
Note: Google Test filter = EventListenerTest.MultiCF
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from EventListenerTest
[ RUN ] EventListenerTest.MultiCF
==================
WARNING: ThreadSanitizer: data race (pid=3377137)
Read of size 8 at 0x7b6000000840 by main thread:
#0 std::vector<rocksdb::DB*, std::allocator<rocksdb::DB*> >::size()
https://github.com/facebook/rocksdb/issues/1 rocksdb::EventListenerTest_MultiCF_Test::TestBody() db/listener_test.cc:384 (listener_test+0x4bb300)
Previous write of size 8 at 0x7b6000000840 by thread T2:
#0 void std::vector<rocksdb::DB*, std::allocator<rocksdb::DB*> >::_M_realloc_insert<rocksdb::DB* const&>(__gnu_cxx::__normal_iterator<rocksdb::DB**, std::vector<rocksdb::DB*, std::allocator<rocksdb::DB*> > >, rocksdb::DB* const&)
https://github.com/facebook/rocksdb/issues/1 std::vector<rocksdb::DB*, std::allocator<rocksdb::DB*> >::push_back(rocksdb::DB* const&)
https://github.com/facebook/rocksdb/issues/2 rocksdb::TestFlushListener::OnFlushCompleted(rocksdb::DB*, rocksdb::FlushJobInfo const&) db/listener_test.cc:255 (listener_test+0x4e820f)
```
- post-fix: `All passed`
Reviewed By: ajkr
Differential Revision: D34085791
Pulled By: hx235
fbshipit-source-id: f877aa687ea1d5cb6f31ef8c4772625d22868e8b
Summary:
The patch replaces `std::map` with a sorted `std::vector` for
`VersionStorageInfo::blob_files_` and preallocates the space
for the `vector` before saving the `BlobFileMetaData` into the
new `VersionStorageInfo` in `VersionBuilder::Rep::SaveBlobFilesTo`.
These changes reduce the time the DB mutex is held while
saving new `Version`s, and using a sorted `vector` also makes
lookups faster thanks to better memory locality.
In addition, the patch introduces helper methods
`VersionStorageInfo::GetBlobFileMetaData` and
`VersionStorageInfo::GetBlobFileMetaDataLB` that can be used by
clients to perform lookups in the `vector`, and does some general
cleanup in the parts of code where blob file metadata are used.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9526
Test Plan:
Ran `make check` and the crash test script for a while.
Performance was tested using a load-optimized benchmark (`fillseq` with vector memtable, no WAL) and small file sizes so that a significant number of files are produced:
```
numactl --interleave=all ./db_bench --benchmarks=fillseq --allow_concurrent_memtable_write=false --level0_file_num_compaction_trigger=4 --level0_slowdown_writes_trigger=20 --level0_stop_writes_trigger=30 --max_background_jobs=8 --max_write_buffer_number=8 --db=/data/ltamasi-dbbench --wal_dir=/data/ltamasi-dbbench --num=800000000 --num_levels=8 --key_size=20 --value_size=400 --block_size=8192 --cache_size=51539607552 --cache_numshardbits=6 --compression_max_dict_bytes=0 --compression_ratio=0.5 --compression_type=lz4 --bytes_per_sync=8388608 --cache_index_and_filter_blocks=1 --cache_high_pri_pool_ratio=0.5 --benchmark_write_rate_limit=0 --write_buffer_size=16777216 --target_file_size_base=16777216 --max_bytes_for_level_base=67108864 --verify_checksum=1 --delete_obsolete_files_period_micros=62914560 --max_bytes_for_level_multiplier=8 --statistics=0 --stats_per_interval=1 --stats_interval_seconds=20 --histogram=1 --memtablerep=skip_list --bloom_bits=10 --open_files=-1 --subcompactions=1 --compaction_style=0 --min_level_to_compress=3 --level_compaction_dynamic_level_bytes=true --pin_l0_filter_and_index_blocks_in_cache=1 --soft_pending_compaction_bytes_limit=167503724544 --hard_pending_compaction_bytes_limit=335007449088 --min_level_to_compress=0 --use_existing_db=0 --sync=0 --threads=1 --memtablerep=vector --allow_concurrent_memtable_write=false --disable_wal=1 --enable_blob_files=1 --blob_file_size=16777216 --min_blob_size=0 --blob_compression_type=lz4 --enable_blob_garbage_collection=1 --seed=<some value>
```
Final statistics before the patch:
```
Cumulative writes: 0 writes, 700M keys, 0 commit groups, 0.0 writes per commit group, ingest: 284.62 GB, 121.27 MB/s
Interval writes: 0 writes, 334K keys, 0 commit groups, 0.0 writes per commit group, ingest: 139.28 MB, 72.46 MB/s
```
With the patch:
```
Cumulative writes: 0 writes, 760M keys, 0 commit groups, 0.0 writes per commit group, ingest: 308.66 GB, 131.52 MB/s
Interval writes: 0 writes, 445K keys, 0 commit groups, 0.0 writes per commit group, ingest: 185.35 MB, 93.15 MB/s
```
Total time to complete the benchmark is 2611 seconds with the patch, down from 2986 secs.
Reviewed By: riversand963
Differential Revision: D34082728
Pulled By: ltamasi
fbshipit-source-id: fc598abf676dce436734d06bb9d2d99a26a004fc
Summary:
For RocksDB 7. Remove deprecated dispose() And as a consequence remove finalize(), which is good Modern Java hygiene.
It is extremely non-deterministic when `finalize()` is called on an object, and resource closure/recovery of underlying native/C++ objects and/or non-memory resource cannot be adequately controlled through GC finalization. The RocksDB Java/JNI interface provides and encourages the use of AutoCloseable objects with close() methods, allowing predictable disposal of resources at exit from try-with-resource blocks.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9523
Reviewed By: mrambacher
Differential Revision: D34079843
Pulled By: jay-zhuang
fbshipit-source-id: d1f0463a89a548b5d57bfaa50154379e722d189a
Summary:
The keys as part of write batch read from trace file can contain trailing timestamps.
This PR removes them before calling `ExpectedState`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9525
Test Plan:
make check
make crash_test_with_ts
Reviewed By: ajkr
Differential Revision: D34082358
Pulled By: riversand963
fbshipit-source-id: 78c925659e2a19e4a8278fb4a8ddf5070e265c04
Summary:
In RocksDB option new_table_reader_for_compaction_inputs has
not effect on Compaction or on the behavior of RocksDB library.
Therefore, we are removing it in the upcoming 7.0 release.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9443
Test Plan: CircleCI
Reviewed By: ajkr
Differential Revision: D33788508
Pulled By: akankshamahajan15
fbshipit-source-id: 324ca6f12bfd019e9bd5e1b0cdac39be5c3cec7d
Summary:
... since it was only necessary to work around a bug on certain Ubuntu
16.04 images (and we now use 20.04 across the board).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9531
Test Plan: Watch CI.
Reviewed By: ajkr
Differential Revision: D34089424
Pulled By: ltamasi
fbshipit-source-id: f15f86332c119099f61b9bdc74604657fc5d964e
Summary:
* Inefficient block-based filter is no longer customizable in the public
API, though (for now) can still be enabled.
* Removed deprecated FilterPolicy::CreateFilter() and
FilterPolicy::KeyMayMatch()
* Removed `rocksdb_filterpolicy_create()` from C API
* Change meaning of nullptr return from GetBuilderWithContext() from "use
block-based filter" to "generate no filter in this case." This is a
cleaner solution to the proposal in https://github.com/facebook/rocksdb/issues/8250.
* Also, when user specifies bits_per_key < 0.5, we now round this down
to "no filter" because we expect a filter with >= 80% FP rate is
unlikely to be worth the CPU cost of accessing it (esp with
cache_index_and_filter_blocks=1 or partition_filters=1).
* bits_per_key >= 0.5 and < 1.0 is still rounded up to 1.0 (for 62% FP
rate)
* This also gives us some support for configuring filters from OPTIONS
file as currently saved: `filter_policy=rocksdb.BuiltinBloomFilter`.
Opening from such an options file will enable reading filters (an
improvement) but not writing new ones. (See Customizable follow-up
below.)
* Also removed deprecated functions
* FilterBitsBuilder::CalculateNumEntry()
* FilterPolicy::GetFilterBitsBuilder()
* NewExperimentalRibbonFilterPolicy()
* Remove default implementations of
* FilterBitsBuilder::EstimateEntriesAdded()
* FilterBitsBuilder::ApproximateNumEntries()
* FilterPolicy::GetBuilderWithContext()
* Remove support for "filter_policy=experimental_ribbon" configuration
string.
* Allow "filter_policy=bloomfilter:n" without bool to discourage use of
block-based filter.
Some pieces for https://github.com/facebook/rocksdb/issues/9389
Likely follow-up (later PRs):
* Refactoring toward FilterPolicy Customizable, so that we can generate
filters with same configuration as before when configuring from options
file.
* Remove support for user enabling block-based filter (ignore `bool
use_block_based_builder`)
* Some months after this change, we could even remove read support for
block-based filter, because it is not critical to DB data
preservation.
* Make FilterBitsBuilder::FinishV2 to avoid `using
FilterBitsBuilder::Finish` mess and add support for specifying a
MemoryAllocator (for cache warming)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9501
Test Plan:
A number of obsolete tests deleted and new tests or test
cases added or updated.
Reviewed By: hx235
Differential Revision: D34008011
Pulled By: pdillinger
fbshipit-source-id: a39a720457c354e00d5b59166b686f7f59e392aa
Summary:
After https://github.com/facebook/rocksdb/issues/9481, we are using newer default compiler for
build-format-compatible CircleCI nightly job, which fails on building
2.2.fb.branch branch because it tries to use a pre-compiled libsnappy.a
that is checked into the repo (!). This works around that by setting
SNAPPY_LDFLAGS=-lsnappy, which is only understood by such old versions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9517
Test Plan:
Run check_format_compatible.sh on Ubuntu 20 AWS machine,
watch nightly run
Reviewed By: hx235
Differential Revision: D34055561
Pulled By: pdillinger
fbshipit-source-id: 45f9d428dd082f026773bfa8d9dd4dad66fc9378
Summary:
... seen only in internal clang-analyze runs after https://github.com/facebook/rocksdb/issues/9481
* Mostly, this works around falsely reported leaks by using
std::unique_ptr in some places where clang-analyze was getting
confused. (I didn't see any changes in C++17 that could make our Status
implementation leak memory.)
* Also fixed SetBGError returning address of a stack variable.
* Also fixed another false null deref report by adding an assert.
Also, use SKIP_LINK=1 to speed up `make analyze`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9515
Test Plan:
Was able to reproduce the reported errors locally and verify
they're fixed (except SetBGError). Otherwise, existing tests
Reviewed By: hx235
Differential Revision: D34054630
Pulled By: pdillinger
fbshipit-source-id: 38600ef3da75ddca307dff96b7a1a523c2885c2e
Summary:
In RocksDB few overloads of DB::GetApproximateSizes are marked as
DEPRECATED_FUNC, and we are removing it in the upcoming 7.0 release.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9458
Test Plan: CircleCI
Reviewed By: riversand963
Differential Revision: D34043791
Pulled By: akankshamahajan15
fbshipit-source-id: 815c0ad283a6627c4b241479c7d40ce03a758493
Summary:
For tiered storage
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9498
Test Plan: Just API placeholders for now
Reviewed By: jay-zhuang
Differential Revision: D33993094
Pulled By: pdillinger
fbshipit-source-id: 3cf19a450c7232e05306e94018559b26e9fd35db
Summary:
The patch builds on the refactoring done in https://github.com/facebook/rocksdb/issues/9494
and improves the performance of building the hash of file
locations in `VersionStorageInfo` in two ways. First, the hash
building is moved from `AddFile` (which is called under the DB mutex)
to a separate post-processing step done as part of `PrepareForVersionAppend`
(during which the mutex is *not* held). Second, the space necessary
for the hash is preallocated to prevent costly reallocation/rehashing
operations. These changes mitigate the overhead of the file location hash,
which can be significant with certain workloads where the baseline CPU usage
is low (see https://github.com/facebook/rocksdb/issues/9351,
which is a workload where keys are sorted, WAL is turned
off, the vector memtable implementation is used, and there are lots of small
SST files).
Fixes https://github.com/facebook/rocksdb/issues/9351
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9504
Test Plan:
`make check`
```
numactl --interleave=all ./db_bench --benchmarks=fillseq --allow_concurrent_memtable_write=false --level0_file_num_compaction_trigger=4 --level0_slowdown_writes_trigger=20 --level0_stop_writes_trigger=30 --max_background_jobs=8 --max_write_buffer_number=8 --db=/data/ltamasi-dbbench --wal_dir=/data/ltamasi-dbbench --num=800000000 --num_levels=8 --key_size=20 --value_size=400 --block_size=8192 --cache_size=51539607552 --cache_numshardbits=6 --compression_max_dict_bytes=0 --compression_ratio=0.5 --compression_type=lz4 --bytes_per_sync=8388608 --cache_index_and_filter_blocks=1 --cache_high_pri_pool_ratio=0.5 --benchmark_write_rate_limit=0 --write_buffer_size=16777216 --target_file_size_base=16777216 --max_bytes_for_level_base=67108864 --verify_checksum=1 --delete_obsolete_files_period_micros=62914560 --max_bytes_for_level_multiplier=8 --statistics=0 --stats_per_interval=1 --stats_interval_seconds=20 --histogram=1 --bloom_bits=10 --open_files=-1 --subcompactions=1 --compaction_style=0 --level_compaction_dynamic_level_bytes=true --pin_l0_filter_and_index_blocks_in_cache=1 --soft_pending_compaction_bytes_limit=167503724544 --hard_pending_compaction_bytes_limit=335007449088 --min_level_to_compress=0 --use_existing_db=0 --sync=0 --threads=1 --memtablerep=vector --disable_wal=1 --seed=<some_seed>
```
Final statistics before this patch:
```
Cumulative writes: 0 writes, 697M keys, 0 commit groups, 0.0 writes per commit group, ingest: 283.25 GB, 241.08 MB/s
Interval writes: 0 writes, 1264K keys, 0 commit groups, 0.0 writes per commit group, ingest: 525.69 MB, 176.67 MB/s
```
With the patch:
```
Cumulative writes: 0 writes, 759M keys, 0 commit groups, 0.0 writes per commit group, ingest: 308.57 GB, 262.63 MB/s
Interval writes: 0 writes, 1555K keys, 0 commit groups, 0.0 writes per commit group, ingest: 646.61 MB, 215.11 MB/s
```
Reviewed By: riversand963
Differential Revision: D34014734
Pulled By: ltamasi
fbshipit-source-id: acb2703677451d5ccaa7e9d950844b33d240695b
Summary:
Thread-pool pops a thread function and then run the function,
which may cause thread-pool is empty but the last function is still
running.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9502
Test Plan:
`gtest-parallel ./env_test
--gtest_filter=DefaultEnvWithoutDirectIO/EnvPosixTestWithParam.RunMany/0
-r 10000 -w 1000`
Reviewed By: ajkr
Differential Revision: D34011184
Pulled By: jay-zhuang
fbshipit-source-id: 8c38bef155205bef96fd1c988dcc643a6b2ac270
Summary:
Ubuntu 16.04 has reached EOL. The patch upgrades the image for all of
our CircleCI jobs to the latest, namely `ubuntu-2004:202111-02`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9486
Test Plan: Watch the CI build results.
Reviewed By: ajkr
Differential Revision: D34029339
Pulled By: ltamasi
fbshipit-source-id: a266b631c04d227fe29b8156be61229605eb9dd7
Summary:
Drop support for some old compilers by requiring C++17 standard
(or higher). See https://github.com/facebook/rocksdb/issues/9388
First modification based on this is to remove some conditional compilation in slice.h (also
better for ODR)
Also in this PR:
* Fix some Makefile formatting that seems to affect ASSERT_STATUS_CHECKED config in
some cases
* Add c_test to NON_PARALLEL_TEST in Makefile
* Fix a clang-analyze reported "potential leak" in lru_cache_test
* Better "compatibility" definition of DEFINE_uint32 for old versions of gflags
* Fix a linking problem with shared libraries in Makefile (`./random_test: error while loading shared libraries: librocksdb.so.6.29: cannot open shared object file: No such file or directory`)
* Always set ROCKSDB_SUPPORT_THREAD_LOCAL and use thread_local (from C++11)
* TODO in later PR: clean up that obsolete flag
* Fix a cosmetic typo in c.h (https://github.com/facebook/rocksdb/issues/9488)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9481
Test Plan:
CircleCI config substantially updated.
* Upgrade to latest Ubuntu images for each release
* Generally prefer Ubuntu 20, but keep a couple Ubuntu 16 builds with oldest supported
compilers, to ensure compatibility
* Remove .circleci/cat_ignore_eagain except for Ubuntu 16 builds, because this is to work
around a kernel bug that should not affect anything but Ubuntu 16.
* Remove designated gcc-9 build, because the default linux build now uses GCC 9 from
Ubuntu 20.
* Add some `apt-key add` to fix some apt "couldn't be verified" errors
* Generally drop SKIP_LINK=1; work-around no longer needed
* Generally `add-apt-repository` before `apt-get update` as manual testing indicated the
reverse might not work.
Travis:
* Use gcc-7 by default (remove specific gcc-7 and gcc-4.8 builds)
* TODO in later PR: fix s390x "Assembler messages: Error: invalid switch -march=z14" failure
AppVeyor:
* Completely dropped because we are dropping VS2015 support and CircleCI covers
VS >= 2017
Also local testing with old gflags (out of necessity when using ROCKSDB_NO_FBCODE=1).
Reviewed By: mrambacher
Differential Revision: D33946377
Pulled By: pdillinger
fbshipit-source-id: ae077c823905b45370a26c0103ada119459da6c1
Summary:
Fixed all RocksJava test failures in Centos and Alpine 32 bit and 64 bit OSes
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9395
Reviewed By: mrambacher
Differential Revision: D33771987
Pulled By: ajkr
fbshipit-source-id: fed91033b8df08f191ad65e1fb745a9264bbfa70
Summary:
Follow-up to https://github.com/facebook/rocksdb/issues/9126
Added new unit tests to validate some of the claims of guaranteed uniqueness
within certain large bounds.
Also cleaned up the cache_bench -stress-cache-key tool with better comments
and description.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9329
Test Plan: no changes to production code
Reviewed By: mrambacher
Differential Revision: D33269328
Pulled By: pdillinger
fbshipit-source-id: 3a2b684a6b2b15f79dc872e563e3d16563be26de
Summary:
The patch does some cleanup in and around `VersionStorageInfo`:
* Renames the method `PrepareApply` to `PrepareAppend` in `Version`
to make it clear that it is to be called before appending the `Version` to
`VersionSet` (via `AppendVersion`), not before applying any `VersionEdit`s.
* Introduces a helper method `VersionStorageInfo::PrepareForVersionAppend`
(called by `Version::PrepareAppend`) that encapsulates the population of the
various derived data structures in `VersionStorageInfo`, and turns the
methods computing the derived structures (`UpdateNumNonEmptyLevels`,
`CalculateBaseBytes` etc.) into private helpers.
* Changes `Version::PrepareAppend` so it only calls `UpdateAccumulatedStats`
if the `update_stats` flag is set. (Earlier, this was checked by the callee.)
Related to this, it also moves the call to `ComputeCompensatedSizes` to
`VersionStorageInfo::PrepareForVersionAppend`.
* Updates and cleans up `version_builder_test`, `version_set_test`, and
`compaction_picker_test` so `PrepareForVersionAppend` is called anytime
a new `VersionStorageInfo` is set up or saved. This cleanup also involves
splitting `VersionStorageInfoTest.MaxBytesForLevelDynamic`
into multiple smaller test cases.
* Fixes up a bunch of comments that were outdated or just plain incorrect.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9494
Test Plan: Ran `make check` and the crash test script for a while.
Reviewed By: riversand963
Differential Revision: D33971666
Pulled By: ltamasi
fbshipit-source-id: fda52faac7783041126e4f8dec0fe01bdcadf65a
Summary:
In RocksDB, this option was already marked as "NOT SUPPORTED" for a long time, and setting this option does not have any effect on the behavior of RocksDB library. Therefore, we are removing it in the preparations of the upcoming 7.0 release.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9446
Reviewed By: ajkr
Differential Revision: D33793048
Pulled By: bjlemaire
fbshipit-source-id: 73316efdb194e90225005246673dae99e65577ae
Summary:
I feel it would be nice if we can fix this spelling error.
In `SizeApproximationOptions`, the `include_memtabtles` should be `include_memtables`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9490
Test Plan: make check
Reviewed By: hx235
Differential Revision: D33949862
Pulled By: riversand963
fbshipit-source-id: b2be67501b65d4aabb6b8df1bf25eb8d54cc1466
Summary:
Added a CountedFileSystem that tracks a number of file operations (opens, closes, deletes, renames, flushes, syncs, fsyncs, reads, writes). This class was based on the ReportFileOpEnv from db_bench.
This is a stepping stone PR to be able to change the SpecialEnv into a SpecialFileSystem, where several of the file varieties wish to do operation counting.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9283
Reviewed By: pdillinger
Differential Revision: D33062004
Pulled By: mrambacher
fbshipit-source-id: d0d297a7fb9c48c06cbf685e5fa755c27193b6f5
