Summary:
It was incorrectly counting time even for blocks that didn't need decompression.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6658
Test Plan: make check
Reviewed By: ajkr
Differential Revision: D20883522
Pulled By: anand1976
fbshipit-source-id: 33c9c4683f54cad150ab260a69e3ef8aa9aff76a
Summary:
Adding a simple timer support to schedule work at a fixed time.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6543
Test Plan: TODO: clean up the unit tests, and make them better.
Reviewed By: siying
Differential Revision: D20465390
Pulled By: sagar0
fbshipit-source-id: cba143f70b6339863e1d0f8b8bf92e51c2b3d678
Summary:
The raw key bytes are currently dumped directly into the log messages,
which is not ideal if the keys aren't ASCII strings. Null bytes in
particular can cut off bits of the message early.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6616
Reviewed By: ajkr
Differential Revision: D20879218
Pulled By: anand1976
fbshipit-source-id: 825a20715fe6d8012c0163c6e7b8159f7926a1a7
Summary:
When Travis times out, it's hard to determine whether
the last executing thing took an excessively long time or the
sum of all the work just exceeded the time limit. This
change inserts some timestamps in the output that should
make this easier to determine.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6643
Test Plan: CI (Travis mostly)
Reviewed By: anand1976
Differential Revision: D20843901
Pulled By: pdillinger
fbshipit-source-id: e7aae5434b0c609931feddf238ce4355964488b7
Summary:
https://github.com/facebook/rocksdb/pull/6262 causes CLANG analyze to complain. Add assertion to suppress the warning.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6641
Test Plan: Run "clang analyze" and make sure it passes.
Reviewed By: anand1976
Differential Revision: D20841722
fbshipit-source-id: 5fa6e0c5cfe7a822214c9b898a408df59d4fd2cd
Summary:
This is a predecessor to the Configurable PR. This change moves the OptionTypeInfo maps closer to where they will be used.
When the Configurable changes are adopted, these values will become static and not associated with the OptionsHelper.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6198
Reviewed By: siying
Differential Revision: D20778108
Pulled By: zhichao-cao
fbshipit-source-id: a9f85fc73bc53503656e1958ecc1e764052fd1aa
Summary:
I suspect LRUCache could use some optimization, and to support
such an effort, a good benchmarking tool is needed. The existing
cache_bench was heavily skewed toward insertion and lookup misses, and
did not saturate memory with other work. This change should improve
those things to better resemble a real workload.
(All below using clang compiler, for some consistency, but not
necessarily same version and settings.)
The real workload is from production MySQL on RocksDB, filtering stacks
containing "LRU", "ShardedCache" or "CacheShard."
Lookup inclusive: 66%
Insert inclusive: 17%
Release inclusive: 15%
An alternate simulated workload is MySQL running a LinkBench read test:
Lookup inclusive: 54%
Insert inclusive: 24%
Release inclusive: 21%
cache_bench default settings, prior to this change:
Lookup inclusive: 35.8%
Insert inclusive: 63.6%
Release inclusive: 0%
cache_bench after this change (intended as somewhat "tighter" workload
than average production, more like LinkBench):
Lookup inclusive: 52%
Insert inclusive: 20%
Release inclusive: 26%
And top exclusive stacks (portion of stack samples as filtered above):
Production MySQL:
LRUHandleTable::FindPointer: 25.3%
rocksdb::operator==: 15.1% <-- Slice ==
LRUCacheShard::LRU_Remove: 13.8%
ShardedCache::Lookup: 8.9%
__pthread_mutex_lock: 7.1%
LRUCacheShard::LRU_Insert: 6.3%
MurmurHash64A: 4.8% <-- Since upgraded to XXH3p
...
Old cache_bench:
LRUHandleTable::FindPointer: 23.6%
__pthread_mutex_lock: 15.0%
__pthread_mutex_unlock_usercnt: 11.7%
__lll_lock_wait: 8.6%
__lll_unlock_wake: 6.8%
LRUCacheShard::LRU_Insert: 6.0%
ShardedCache::Lookup: 4.4%
LRUCacheShard::LRU_Remove: 2.8%
...
rocksdb::operator==: 0.2% <-- Slice ==
...
New cache_bench:
LRUHandleTable::FindPointer: 22.8%
__pthread_mutex_unlock_usercnt: 14.3%
rocksdb::operator==: 10.5% <-- Slice ==
LRUCacheShard::LRU_Insert: 9.0%
__pthread_mutex_lock: 5.9%
LRUCacheShard::LRU_Remove: 5.0%
...
ShardedCache::Lookup: 2.9%
...
So there's a bit more lock contention in the benchmark than in
production, but otherwise looks similar enough to me. At least it's a
big improvement over the existing code.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6629
Test Plan: No production code changes, ran cache_bench with ASAN
Reviewed By: ltamasi
Differential Revision: D20824318
Pulled By: pdillinger
fbshipit-source-id: 6f8dc5891ead0f87edbed3a615ecd5289d9abe12
Summary:
In CompactionManifestWriteRetryableError in error_handler_fs_test, the manifest write of flush should pass with no fs error. After flush, fs is set to error status and the manifest write of compaction should fail due to the IO Error. Currently, the manifest write of flush is not synced with the compaction in order, which might cause manifest write fails, which will cause test failure. Fixed by adding the LoadDependency of sync-point after flush and before compaction.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6637
Test Plan: pass error_hanlder_fs_tes. Pass make asan_check
Reviewed By: anand1976
Differential Revision: D20826969
Pulled By: zhichao-cao
fbshipit-source-id: fb2e702caa19bd63c82570320536b7acda870ff1
Summary:
With https://github.com/facebook/rocksdb/issues/6262, TSAN complains about data race of some variables. Those variables are used to estimate file size and are accessed in writer and background threads. Since file size estimation doesn't have to be 100% accurate, we make some variables atomic and use relaxed memory order.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6636
Test Plan: Run all tests with TSAN.
Reviewed By: anand1976
Differential Revision: D20820635
fbshipit-source-id: 1ea45ff38be15e33674ffe06b7d42fc9fe161ea5
Summary:
With https://github.com/facebook/rocksdb/issues/6262, UBSAN fails with "division by zero":
[ RUN ] Timestamp/DBBasicTestWithTimestampCompressionSettings.PutAndGetWithCompaction/3
internal_repo_rocksdb/repo/table/block_based/block_based_table_builder.cc:1066:39: runtime error: division by zero
#0 0x7ffb3117b071 in rocksdb::BlockBasedTableBuilder::WriteRawBlock(rocksdb::Slice const&, rocksdb::CompressionType, rocksdb::BlockHandle*, bool) internal_repo_rocksdb/repo/table/block_based/block_based_table_builder.cc:1066
https://github.com/facebook/rocksdb/issues/1 0x7ffb311775e1 in rocksdb::BlockBasedTableBuilder::WriteBlock(rocksdb::Slice const&, rocksdb::BlockHandle*, bool) internal_repo_rocksdb/repo/table/block_based/block_based_table_builder.cc:848
https://github.com/facebook/rocksdb/issues/2 0x7ffb311771a2 in rocksdb::BlockBasedTableBuilder::WriteBlock(rocksdb::BlockBuilder*, rocksdb::BlockHandle*, bool) internal_repo_rocksdb/repo/table/block_based/block_based_table_builder.cc:832
This is caused by not returning immediately after CompressAndVerifyBlock call
in WriteBlock when rep_->status == kBuffered.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6633
Test Plan: Run all existing test.
Reviewed By: anand1976
Differential Revision: D20808366
fbshipit-source-id: 09f24b7c0fbaf4c7a8fc48cac61fa6fcb9b85811
Summary:
Does what it says on the can. Similarly to table files, we need to re-persist
the metadata of live blob files whenever a new manifest file is opened.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6630
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D20802126
Pulled By: ltamasi
fbshipit-source-id: 5738692d898790293bf09d66e9997369bbf89566
Summary:
Add `encrypt_data_time` and `decrypt_data_time` perf_context counters to time encryption/decryption time when `EnvEncryption` is enabled.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6596
Test Plan: CI
Reviewed By: anand1976
Differential Revision: D20678617
fbshipit-source-id: 7b57536143aa38509cde011f704de33382169e07
Summary:
This PR adds support for pipelined & parallel compression optimization for `BlockBasedTableBuilder`. This optimization makes block building, block compression and block appending a pipeline, and uses multiple threads to accelerate block compression. Users can set `CompressionOptions::parallel_threads` greater than 1 to enable compression parallelism.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6262
Reviewed By: ajkr
Differential Revision: D20651306
fbshipit-source-id: 62125590a9c15b6d9071def9dc72589c1696a4cb
Summary:
https://github.com/facebook/rocksdb/issues/6247 reports that when write buffer manager fails to insert the dummy entry to block cache, null pointer is still stored and used to release the handle and cause corruption. Fix the bug by not releasing it with null handle.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6619
Test Plan: Add a unit test that fails without the fix.
Reviewed By: ajkr
Differential Revision: D20776769
fbshipit-source-id: 4127fbd9f295a0a3e45774746ffcd91f939f6287
Summary:
These three options should be made dynamically changeable. Simply add them to MutableCFOptions and made the change.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6615
Test Plan: Add a unit test to make sure that SetOptions() can change the options.
Reviewed By: riversand963
Differential Revision: D20755951
fbshipit-source-id: 8165f4fd7a7a665cc7fb049698935022a5d2e7ff
Summary:
For FIFO compaction, we use flush time instead of oldest key time as the
creation time. This is to prevent FIFO compaction dropping files whose oldest
key time is older than TTL but which has newer keys than TTL.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6612
Test Plan: make check
Reviewed By: siying
Differential Revision: D20748217
Pulled By: riversand963
fbshipit-source-id: 3f7b00a847020760537cdddd12f6fe039e5bc663
Summary:
The checksum generator should be released if file_writer fails to reset the pointer.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6611
Test Plan: pass make asan_check
Reviewed By: riversand963
Differential Revision: D20742964
Pulled By: zhichao-cao
fbshipit-source-id: cde41be2edb3d1e56083c2b93e1510fb32556146
Summary:
This change updates PosixSequentialFile::Read to call clearerr()
before fread()ing again after an EINTR is returned on a previous
fread.
The original fix is from bd8f1ebb91.
Fixing https://github.com/facebook/rocksdb/issues/6509
Signed-off-by: phantomape <cxucheng@outlook.com>
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6609
Reviewed By: zhichao-cao
Differential Revision: D20731482
Pulled By: riversand963
fbshipit-source-id: 7f1f3a1449077d5560f45c465a78d08633740ba0
Summary:
In the current implementation, sst file checksum is calculated by a shared checksum function object, which may make some checksum function hard to be applied here such as SHA1. In this implementation, each sst file will have its own checksum generator obejct, created by FileChecksumGenFactory. User needs to implement its own FilechecksumGenerator and Factory to plugin the in checksum calculation method.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6600
Test Plan: tested with make asan_check
Reviewed By: riversand963
Differential Revision: D20717670
Pulled By: zhichao-cao
fbshipit-source-id: 2a74c1c280ac11a07a1980185b43b671acaa71c6
Summary:
When creating a database backup, the background threads will not only consume IO resources by copying files, but also consuming CPU such as by computing checksums. During peak times, the CPU consumption by the background threads might affect online queries.
This PR makes it possible to decrease CPU priority of these threads when creating a new backup.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6602
Test Plan: make check
Reviewed By: siying, zhichao-cao
Differential Revision: D20683216
Pulled By: cheng-chang
fbshipit-source-id: 9978b9ed9488e8ce135e90ca083e5b4b7221fd84
Summary:
1. If expiration_time is non-positive, no need to call NowMicros, save a syscall.
2. expire_time should only be set when expired is false.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6586
Test Plan: make check
Reviewed By: lth
Differential Revision: D20673730
Pulled By: cheng-chang
fbshipit-source-id: a69e8d7b16dc6d0d00487bb1c19f0710d79482e2
Summary:
In the current code base, we use Status to get and store the returned status from the call. Specifically, for IO related functions, the current Status cannot reflect the IO Error details such as error scope, error retryable attribute, and others. With the implementation of https://github.com/facebook/rocksdb/issues/5761, we have the new Wrapper for IO, which returns IOStatus instead of Status. However, the IOStatus is purged at the lower level of write path and transferred to Status.
The first job of this PR is to pass the IOStatus to the write path (flush, WAL write, and Compaction). The second job is to identify the Retryable IO Error as HardError, and set the bg_error_ as HardError. In this case, the DB Instance becomes read only. User is informed of the Status and need to take actions to deal with it (e.g., call db->Resume()).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6487
Test Plan: Added the testing case to error_handler_fs_test. Pass make asan_check
Reviewed By: anand1976
Differential Revision: D20685017
Pulled By: zhichao-cao
fbshipit-source-id: ff85f042896243abcd6ef37877834e26f36b6eb0
Summary:
The last key may hit index of out bound exception when id = 9.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6574
Reviewed By: riversand963
Differential Revision: D20699791
Pulled By: cheng-chang
fbshipit-source-id: 8e2c5be5ff0e53e9857cfd59cea97cff21446819
Summary:
This test was written like a stress test, using up to 3x26GB
RSS memory during parallel 'make check'. Now, while this code is mostly
dormant, I've made the "for Travis" versions of the expensive tests the
canonical versions and disabled the expensive versions. This has the
side benefit of removing some arbitrary conditional compilation.
For unknown reason, the super expensive tests were gated on
Snappy_Supported, which appears to be irrelevant, so I removed it.
The tests can be fixed / improved / migrated to stress test if/when they
are deemed important again.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6601
Test Plan:
make check + CI
./persistent_cache_test Before:
...
[==========] 10 tests from 2 test cases ran. (114541 ms total)
[ PASSED ] 10 tests.
YOU HAVE 1 DISABLED TEST
After:
...
[==========] 3 tests from 2 test cases ran. (1714 ms total)
[ PASSED ] 3 tests.
YOU HAVE 10 DISABLED TESTS
Reviewed By: siying
Differential Revision: D20680983
Pulled By: pdillinger
fbshipit-source-id: 2be0fde13eeb0a71110ac7f5477cfe63996a509e
Summary:
The patch adds a couple of classes to represent metadata about
blob files: `SharedBlobFileMetaData` contains the information elements
that are immutable (once the blob file is closed), e.g. blob file number,
total number and size of blob files, checksum method/value, while
`BlobFileMetaData` contains attributes that can vary across versions like
the amount of garbage in the file. There is a single `SharedBlobFileMetaData`
for each blob file, which is jointly owned by the `BlobFileMetaData` objects
that point to it; `BlobFileMetaData` objects, in turn, are owned by `Version`s
and can also be shared if the (immutable _and_ mutable) state of the blob file
is the same in two versions.
In addition, the patch adds the blob file metadata to `VersionStorageInfo`, and extends
`VersionBuilder` so that it can apply blob file related `VersionEdit`s (i.e. those
containing `BlobFileAddition`s and/or `BlobFileGarbage`), and save blob file metadata
to a new `VersionStorageInfo`. Consistency checks are also extended to ensure
that table files point to blob files that are part of the `Version`, and that all blob files
that are part of any given `Version` have at least some _non_-garbage data in them.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6597
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D20656803
Pulled By: ltamasi
fbshipit-source-id: f1f74d135045b3b42d0146f03ee576ef0a4bfd80
Summary:
As the first step of reintroducing eviction statistics for the block
cache, the patch switches from using simple function pointers as deleters
to function objects implementing an interface. This will enable using
deleters that have state, like a smart pointer to the statistics object
that is to be updated when an entry is removed from the cache. For now,
the patch adds a deleter template class `SimpleDeleter`, which simply
casts the `value` pointer to its original type and calls `delete` or
`delete[]` on it as appropriate. Note: to prevent object lifecycle
issues, deleters must outlive the cache entries referring to them;
`SimpleDeleter` ensures this by using the ("leaky") Meyers singleton
pattern.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6545
Test Plan: `make asan_check`
Reviewed By: siying
Differential Revision: D20475823
Pulled By: ltamasi
fbshipit-source-id: fe354c33dd96d9bafc094605462352305449a22a
Summary:
Forward compatibility with new defaults only starts from 5.16
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6598
Test Plan: facebook automated test (so much easier than running myself)
Reviewed By: riversand963
Differential Revision: D20665553
Pulled By: pdillinger
fbshipit-source-id: b846bfaccf4d0946f92d323a3b4ee6e3e548df93
Summary:
And add releases that should have been added before (6.6 - 6.8)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6594
Test Plan: facebook automated test (so much easier than running myself)
Reviewed By: riversand963
Differential Revision: D20649106
Pulled By: pdillinger
fbshipit-source-id: 78832449d9295580282cebf117e3968362fbdc69
Summary:
Version 4 has been around long enough, for compatibility and
extensive validation, that it should be default.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6582
Test Plan:
CI (w.r.t. changing the default; format_version=4 is well
tested and massively in production at Facebook)
Reviewed By: siying
Differential Revision: D20625233
Pulled By: pdillinger
fbshipit-source-id: 2f83ed874cffa4a39bc7a66cdf3833b978fbb948
Summary:
In automatic compaction, if a compaction is bottommost, it goes to bottom thread pool. We should do the same for manual compaction too.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6593
Test Plan: Add a unit test. See all existing tests pass.
Reviewed By: ajkr
Differential Revision: D20637408
fbshipit-source-id: cb03031e8f895085f7acf6d2d65e69e84c9ddef3
Summary:
Create a thread in DeleteScheduler only when delete rate limit is set
because when there is no rate limit on deletion, a thread per DeleteScheduler
consumes unnecessary resources.
Test Plan: make -j64 check
Reviewed By: riversand963
Differential Revision: D20538138
Pulled By: akankshamahajan15
fbshipit-source-id: 137499e810e817156345c30d627f8678b9adadf7
Summary:
Add timestamp support for MultiGet().
timestamp from readoptions is honored, and timestamps can be returned along with values.
MultiReadRandom perf test (10 minutes) on the same development machine ram drive with the same DB data shows no regression (within marge of error). The test is adapted from https://github.com/facebook/rocksdb/wiki/RocksDB-In-Memory-Workload-Performance-Benchmarks.
base line (commit 17bef7d3a):
multireadrandom : 104.173 micros/op 307167 ops/sec; (5462999 of 5462999 found)
This PR:
multireadrandom : 104.199 micros/op 307095 ops/sec; (5307999 of 5307999 found)
.\db_bench --db=r:\rocksdb.github --num_levels=6 --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 --cache_size=2147483648 --cache_numshardbits=6 --compression_type=none --compression_ratio=1 --min_level_to_compress=-1 --disable_seek_compaction=1 --hard_rate_limit=2 --write_buffer_size=134217728 --max_write_buffer_number=2 --level0_file_num_compaction_trigger=8 --target_file_size_base=134217728 --max_bytes_for_level_base=1073741824 --disable_wal=0 --wal_dir=r:\rocksdb.github\WAL_LOG --sync=0 --verify_checksum=1 --statistics=0 --stats_per_interval=0 --stats_interval=1048576 --histogram=0 --use_plain_table=1 --open_files=-1 --memtablerep=prefix_hash --bloom_bits=10 --bloom_locality=1 --duration=600 --benchmarks=multireadrandom --use_existing_db=1 --num=25000000 --threads=32 --allow_concurrent_memtable_write=0
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6483
Reviewed By: anand1976
Differential Revision: D20498373
Pulled By: riversand963
fbshipit-source-id: 8505f22bc40fd791bc7dd05e48d7e67c91edb627
Summary:
When applying a new version in non DB open case, optimize_filters_for_hits is used for max_threads, which is clearly a bug. It is not clear what the indented value in the first place, but it value 1 makes sense here, which would create no extra threads. This bug is not expected to cause user visible problems, assuming C++ implicitly cast bool to 0 or 1.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6576
Test Plan: Run all exsiting test.
Reviewed By: ajkr
Differential Revision: D20602467
fbshipit-source-id: 40b2cd8619aba09ae9242b36c415464db3c9b737
Summary:
The current Env/FileSystem API separation has a couple of issues -
1. It requires the user to specify 2 options - ```Options::env``` and ```Options::file_system``` - which means they have to make code changes to benefit from the new APIs. Furthermore, there is a risk of accessing the same APIs in two different ways, through Env in the old way and through FileSystem in the new way. The two may not always match, for example, if env is ```PosixEnv``` and FileSystem is a custom implementation. Any stray RocksDB calls to env will use the ```PosixEnv``` implementation rather than the file_system implementation.
2. There needs to be a simple way for the FileSystem developer to instantiate an Env for backward compatibility purposes.
This PR solves the above issues and simplifies the migration in the following ways -
1. Embed a shared_ptr to the ```FileSystem``` in the ```Env```, and remove ```Options::file_system``` as a configurable option. This way, no code changes will be required in application code to benefit from the new API. The default Env constructor uses a ```LegacyFileSystemWrapper``` as the embedded ```FileSystem```.
1a. - This also makes it more robust by ensuring that even if RocksDB
has some stray calls to Env APIs rather than FileSystem, they will go
through the same object and thus there is no risk of getting out of
sync.
2. Provide a ```NewCompositeEnv()``` API that can be used to construct a
PosixEnv with a custom FileSystem implementation. This eliminates an
indirection to call Env APIs, and relieves the FileSystem developer of
the burden of having to implement wrappers for the Env APIs.
3. Add a couple of missing FileSystem APIs - ```SanitizeEnvOptions()``` and
```NewLogger()```
Tests:
1. New unit tests
2. make check and make asan_check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6552
Reviewed By: riversand963
Differential Revision: D20592038
Pulled By: anand1976
fbshipit-source-id: c3801ad4153f96d21d5a3ae26c92ba454d1bf1f7
Summary:
`scratch` is not initialized in `Align` because it will be set outside of it. But clang analyzer is strict on initializing it before return.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6577
Test Plan: make analyze
Reviewed By: siying
Differential Revision: D20607303
Pulled By: cheng-chang
fbshipit-source-id: 2843d759345a057a8e122178d30b90deff0f9b2a
Summary:
The MultiGet test in db_basic_test fails in CircleCI vs2019. The reason is that even Snappy compression is enabled, the first compression type is still kNoCompression. This PR checks the list and ensure that only when compression is enable and the compression type is valid, compression will be enabled. Such that, it will not fail the combined read test in MultiGet.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6578
Test Plan: make check, db_basic_test.
Reviewed By: anand1976
Differential Revision: D20607529
Pulled By: zhichao-cao
fbshipit-source-id: dcead264d5c2da105912c18caad34b8510bb04b0
anand76
