Commit Graph

393 Commits

Author SHA1 Message Date
Andrew Kryczka
114a1b8792 Fix build errors for windows
Summary:
- Need to use unsigned long long for 64-bit literals on windows
- Need size_t for backup meta-file length since clang doesn't let us assign size_t to int

Test Plan: backupable_db_test and options_test

Reviewers: IslamAbdelRahman, yhchiang, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D56391
2016-04-08 13:09:19 -07:00
flabby
ada88b63f5 fix wrong assignment of level0_stop_writes_trigger in spatialdb (#1061) 2016-04-07 09:02:28 -07:00
Islam AbdelRahman
d02eb8d00b Fix unused variable warning
Summary:
My last diff introduced a warning when compiling under release mode
https://reviews.facebook.net/D55539

fix the warning

Test Plan:
DEBUG_LEVEL=0 make db_bench
make check

Reviewers: sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D56295
2016-04-04 11:10:46 -07:00
Islam AbdelRahman
f38540b12a WriteBatchWithIndex micro optimization
Summary:
  - Put key offset and key size in WriteBatchIndexEntry
  - Use vector for comparators in WriteBatchEntryComparator

I use a slightly modified version of @yoshinorim code to benchmark
https://gist.github.com/IslamAbdelRahman/b120f4fba8d6ff7d58d2

For Put I create a transaction that put a 1000000 keys and measure the time spent without commit.
For GetForUpdate I read the keys that I added in the Put transaction.

Original time:

```
 rm -rf /dev/shm/rocksdb-example/
 ./txn_bench put 1000000
 1000000 OK Ops | took      3.679 seconds
 ./txn_bench get_for_update 1000000
 1000000 OK Ops | took      3.940 seconds
```

New Time

```
  rm -rf /dev/shm/rocksdb-example/
 ./txn_bench put 1000000
 1000000 OK Ops | took      2.727 seconds
 ./txn_bench get_for_update 1000000
 1000000 OK Ops | took      3.880 seconds
```

It looks like there is no significant improvement in GetForUpdate() but we can see ~30% improvement in Put()

Test Plan: unittests

Reviewers: yhchiang, anthony, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba, yoshinorim

Differential Revision: https://reviews.facebook.net/D55539
2016-04-01 15:23:46 -07:00
Uddipta Maity
b55e2165be Rocksdb backup can store optional application specific metadata
Summary:
Rocksdb backup engine maintains metadata about backups in separate files. But,
there was no way to add extra application specific data to it. Adding support
for that.
In some use cases, applications decide to restore a backup based on some
metadata. This will help those cases to cheaply decide whether to restore or
not.

Test Plan:
Added a unit test. Existing ones are passing

Sample meta file for BinaryMetadata test-

```

1459454043
0
metadata 6162630A64656600676869
2
private/1/MANIFEST-000001 crc32 1184723444
private/1/CURRENT crc32 3505765120

```

Reviewers: sdong, ldemailly, andrewkr

Reviewed By: andrewkr

Subscribers: andrewkr, dhruba, ldemailly

Differential Revision: https://reviews.facebook.net/D56007
2016-04-01 10:56:52 -07:00
Andrew Kryczka
72224104d3 Forge current file for checkpoint
Summary:
This fixes a similar issue as D54711: "CURRENT" file can mutate between
GetLiveFiles() and copy to the tmp directory, in which case it would reference
the wrong manifest filename. To fix this, I forge the "CURRENT" file such that
it simply contains the filename for the manifest returned by GetLiveFiles().

- Changed CreateCheckpoint() to forge current file
- Added CreateFile() utility function
- Added test case that rolls manifest during checkpoint creation

Test Plan:
  $ ./checkpoint_test

Reviewers: sdong, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D55065
2016-03-17 10:07:21 -07:00
SherlockNoMad
f11b0df121 Fix AppVeyor build error 2016-03-15 10:57:33 -07:00
agiardullo
790252805d Add multithreaded transaction test
Summary: Refactored db_bench transaction stress tests so that they can be called from unit tests as well.

Test Plan: run new unit test as well as db_bench

Reviewers: yhchiang, IslamAbdelRahman, sdong

Reviewed By: IslamAbdelRahman

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D55203
2016-03-11 15:16:52 -08:00
Andrew Kryczka
d9620239d2 Cleanup stale manifests outside of full purge
Summary:
- Keep track of obsolete manifests in VersionSet
- Updated FindObsoleteFiles() to put obsolete manifests in the JobContext for later use by PurgeObsoleteFiles()
- Added test case that verifies a stale manifest is deleted by a non-full purge

Test Plan:
  $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation

Reviewers: IslamAbdelRahman, yoshinorim, sdong

Reviewed By: sdong

Subscribers: andrewkr, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D55269
2016-03-10 18:16:21 -08:00
agiardullo
2200295ee1 optimistic transactions support for reinitialization
Summary: Extend optimization in D53835 to optimistic transactions for completeness.

Test Plan: added test

Reviewers: sdong, IslamAbdelRahman, horuff, jkedgar

Reviewed By: horuff

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D55059
2016-03-07 19:03:09 -08:00
agiardullo
200080ed72 Improve snapshot handling for Transaction reinitialization
Summary: Previously, reusing a transaction (by passing it as an argument to BeginTransaction) would not clear the transaction's snapshot.  This is not a clear, well-definited behavior.

Test Plan: improved test

Reviewers: sdong, IslamAbdelRahman, horuff, jkedgar

Reviewed By: jkedgar

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D55053
2016-03-07 13:28:11 -08:00
SherlockNoMad
58ecd91326 Fix Windows build 2016-03-03 15:08:24 -08:00
Andrew Kryczka
501927ffc4 [backupable db] Remove file size embedded in name workaround
Summary:
Now that we get sizes efficiently, we no longer need the workaround to
embed file size in filename.

Test Plan:
  $ ./backupable_db_test

Reviewers: sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D55035
2016-03-03 13:32:20 -08:00
Andrew Kryczka
f8e90e8753 Get file attributes in bulk for VerifyBackup and CreateNewBackup
Summary:
For VerifyBackup(), backup files can be spread across "shared/",
"shared_checksum/", and "private/" subdirectories, so we have to
bulk get all three.

For CreateNewBackup(), we make two separate bulk calls: one for the
data files and one for WAL files.

There is also a new helper function, ExtendPathnameToSizeBytes(),
that translates the file attributes vector to a map. I decided to leave
GetChildrenFileAttributes()'s (from D53781) return type as vector to
keep it consistent with GetChildren().

Depends on D53781.

Test Plan:
verified relevant unit tests

  $ ./backupable_db_test

Reviewers: IslamAbdelRahman, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D53919
2016-03-01 19:33:33 -08:00
agiardullo
5ea9aa3c14 TransactionDB:ReinitializeTransaction
Summary: Add function to reinitialize a transaction object so that it can be reused.  This is an optimization so users can potentially avoid reallocating transaction objects.

Test Plan: added tests

Reviewers: yhchiang, kradhakrishnan, IslamAbdelRahman, sdong

Reviewed By: sdong

Subscribers: jkedgar, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D53835
2016-02-29 16:27:32 -08:00
Andrew Kryczka
69c471bd9b Handle concurrent manifest update and backup creation
Summary:
Fixed two related race conditions in backup creation.

(1) CreateNewBackup() uses DB::DisableFileDeletions() to prevent table files
from being deleted while it is copying; however, the MANIFEST file could still
rotate during this time. The fix is to stop deleting the old manifest in the
rotation logic. It will be deleted safely later when PurgeObsoleteFiles() runs
(can only happen when file deletions are enabled).

(2) CreateNewBackup() did not account for the CURRENT file being mutable.
This is significant because the files returned by GetLiveFiles() contain a
particular manifest filename, but the manifest to which CURRENT refers can
change at any time. This causes problems when CURRENT changes between the call
to GetLiveFiles() and when it's copied to the backup directory. To workaround this, I
manually forge a CURRENT file referring to the manifest filename returned in
GetLiveFiles().

(2) also applies to the checkpointing code, so let me know if this approach is
good and I'll make the same change there.

Test Plan:
new test for roll manifest during backup creation.

running the test before this change:

  $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation
  ...
  IO error: /tmp/rocksdbtest-9383/backupable_db/MANIFEST-000001: No such file or directory

running the test after this change:

  $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation
  ...
  [ RUN      ] BackupableDBTest.ChangeManifestDuringBackupCreation
  [       OK ] BackupableDBTest.ChangeManifestDuringBackupCreation (2836 ms)

Reviewers: IslamAbdelRahman, anthony, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D54711
2016-02-29 12:56:55 -08:00
Andrew Kryczka
69c98f0431 Reorder instance variables in backup test for proper destruction order
Summary:
As titled. This fixes the tsan error caused by logger_ being used in
backup_engine_'s destructor. It does not fix the transient unit test failure,
which is caused by MANIFEST file changing while backup is happening.

Test Plan:
verified the tsan error no longer happens on either success or
failure.

  $ COMPILE_WITH_TSAN=1 make -j32 backupable_db_test
  $ while ./backupable_db_test --gtest_filter=BackupableDBTest.CorruptionsTest ; do : ; done

Reviewers: sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D54669
2016-02-24 10:32:11 -08:00
Yueh-Hsuan Chiang
79ca039eb4 Relax the check condition of prefix_extractor in CheckOptionsCompatibility
Summary:
Relax the check condition of prefix_extractor in CheckOptionsCompatibility
by allowing changing value from non-nullptr to nullptr or nullptr to
non-nullptr.

Test Plan:
options_test
options_util_test

Reviewers: sdong, anthony, IslamAbdelRahman, kradhakrishnan, gunnarku

Reviewed By: gunnarku

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D54477
2016-02-19 14:42:24 -08:00
agiardullo
d08d50295c Fix transaction locking
Summary: Broke transaction locking in 4.4 in D52197.  Will cherry-pick this change into 4.4 (which hasn't yet been fully released).  Repro'd using db_bench.

Test Plan: unit tests and db_Bench

Reviewers: sdong, yhchiang, kradhakrishnan, ngbronson

Reviewed By: ngbronson

Subscribers: ngbronson, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D54021
2016-02-16 17:15:05 -08:00
reid horuff
5bcf952a87 Fix WriteImpl empty batch hanging issue
Summary: There is an issue in DBImpl::WriteImpl where if an empty writebatch comes in and sync=true then the logs will be marked as being synced yet the sync never actually happens because there is no data in the writebatch. This causes the next incoming batch to hang while waiting for the logs to complete syncing. This fix syncs logs even if the writebatch is empty.

Test Plan: DoubleEmptyBatch unit test in transaction_test.

Reviewers: yoshinorim, hermanlee4, sdong, ngbronson, anthony

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D54057
2016-02-16 12:21:33 -08:00
Igor Canadi
c90d63a23d can_unlock set but not used
Test Plan: I couldn't repro, but I hope this fixes it. See the error here: https://evergreen.mongodb.com/task_log_raw/mongodb_mongo_master_ubuntu1404_rocksdb_compile_6e9fd902d5cb25aef992363efa128640affd5196_16_02_11_04_33_37/0?type=T

Reviewers: yhchiang, andrewkr, sdong, anthony

Reviewed By: anthony

Subscribers: meyering, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D54123
2016-02-16 11:24:40 -08:00
Yueh-Hsuan Chiang
3a67bffaa8 Fix an ASAN error in transaction_test.cc
Summary:
One test in transaction_test.cc forgets to call SyncPoint::DisableProcessing().
As a result, a program might to access the SyncPoint singleton after it
already goes out of scope.

This patch fix this error by calling SyncPoint::DisableProcessing().

Test Plan: transaction_test

Reviewers: sdong, IslamAbdelRahman, kradhakrishnan, anthony

Reviewed By: anthony

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D54033
2016-02-10 12:06:59 -08:00
Yueh-Hsuan Chiang
2a04268be3 Temporarily disable unstable tests in memory_test.cc
Summary:
memory_test.cc has some tests that are not unstable but
hard to reproduce, and the cause is the test itself not
the code.  Temporarily disable the tests until
we have a good fix.

Test Plan: memory_test

Reviewers: sdong, anthony, IslamAbdelRahman, rven, kradhakrishnan

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D54009
2016-02-09 16:28:34 -08:00
Baraa Hamodi
21e95811d1 Updated all copyright headers to the new format. 2016-02-09 15:12:00 -08:00
agiardullo
fe93bf9b5d Transaction::UndoGetForUpdate
Summary: MyRocks wants to be able to un-lock a key that was just locked by GetForUpdate().  To do this safely, I am now keeping track of the number of reads(for update) and writes for each key in a transaction.  UndoGetForUpdate() will only unlock a key if it hasn't been written and the read count reaches 0.

Test Plan: more unit tests

Reviewers: igor, rven, yhchiang, spetrunia, sdong

Reviewed By: spetrunia, sdong

Subscribers: spetrunia, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D47043
2016-02-09 10:46:11 -08:00
reid horuff
6f71d3b68b Improve perf of Pessimistic Transaction expirations (and optimistic transactions)
Summary:
copy from task 8196669:

1) Optimistic transactions do not support batching writes from different threads.
2) Pessimistic transactions do not support batching writes if an expiration time is set.

In these 2 cases, we currently do not do any write batching in DBImpl::WriteImpl() because there is a WriteCallback that could decide at the last minute to abort the write.  But we could support batching write operations with callbacks if we make sure to process the callbacks correctly.

To do this, we would first need to modify write_thread.cc to stop preventing writes with callbacks from being batched together.  Then we would need to change DBImpl::WriteImpl() to call all WriteCallback's in a batch, only write the batches that succeed, and correctly set the state of each batch's WriteThread::Writer.

Test Plan: Added test WriteWithCallbackTest to write_callback_test.cc which creates multiple client threads and verifies that writes are batched and executed properly.

Reviewers: hermanlee4, anthony, ngbronson

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D52863
2016-02-05 10:44:13 -08:00
Gabriela Jacques da Silva
0c2bd5cb4b Removing data race from expirable transactions
Summary:
Doing inline checking of transaction expiration instead of
using a callback.

Test Plan: To be added

Reviewers: anthony

Reviewed By: anthony

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D53673
2016-02-02 18:37:44 -08:00
agiardullo
45768ade4f transaction allocation perf improvements
Summary: Removed a couple of memory allocations

Test Plan: changes covered by existing tests

Reviewers: rven, yhchiang, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D53523
2016-01-28 17:32:28 -08:00
Andrew Kryczka
167bd8856d [directory includes cleanup] Finish removing util->db dependencies 2016-01-26 10:49:24 -08:00
David Bernard
df7c2f3b59 As per google coding standard replace "using" in option_builder.cc and
geodb_impl.cc
2016-01-20 00:27:29 +00:00
David Bernard
d78c6b28c4 Changes for build on solaris
Makefile adjust paths for solaris build
Makefile enable _GLIBCXX_USE_C99 so that std::to_string is available
db_compaction_test.cc Initialise a variable to avoid a compilation error
db_impl.cc Include <alloca.h>
db_test.cc Include <alloca.h>
Environment.java recognise solaris envrionment
options_bulder.cc Make log unambiguous
geodb_impl.cc Make log and floor unambiguous
2016-01-19 04:45:21 +00:00
agiardullo
9760c842ce fix valgrind failure in backupable_db_test
Summary: fix memory leak in test code

Test Plan: ran test

Reviewers: rven, igor, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D52617
2016-01-06 18:04:58 -08:00
Igor Canadi
e541dcc8fa Fix issue #921
Summary:
See a bug report here: https://github.com/facebook/rocksdb/issues/921
The fix is to not check the shared/ directory if share_table_files is false. We could also check FileExists() before GetChildren(), but that will add extra latency when Env is Hdfs :(

Test Plan: added a unit test

Reviewers: rven, sdong, IslamAbdelRahman, yhchiang, anthony

Reviewed By: anthony

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D52593
2016-01-06 13:05:24 -08:00
Siying Dong
298ba27ae2 Merge pull request #846 from yuslepukhin/enble_c4244_lossofdata
Enable MS compiler warning c4244.
2015-12-23 22:59:42 -08:00
Siying Dong
7810aa802a Merge pull request #899 from zhipeng-jia/fix_clang_warning
Fix clang warnings
2015-12-23 22:58:52 -08:00
sdong
3280ae9a29 Fix warning in release
Summary: Warning in release build.

Test Plan: Make release and make all

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D52305
2015-12-23 22:38:12 -08:00
Zhipeng Jia
73b175a773 Fix clang warnings regarding unnecessary std::move 2015-12-24 04:10:00 +08:00
agiardullo
eff309867e Do not use timed_mutex in TransactionDB
Summary: Stopped using std::timed_mutex as it has known issues in older versiong of gcc.  Ran into these problems when testing MongoRocks.

Test Plan: unit tests.  Manual mongo testing on gcc 4.8.

Reviewers: igor, yhchiang, rven, IslamAbdelRahman, kradhakrishnan, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D52197
2015-12-18 17:26:02 -08:00
Dmitri Smirnov
b6d19adcf7 Use port size_t formatting 2015-12-15 11:34:22 -08:00
Venkatesh Radhakrishnan
030215bf01 Running manual compactions in parallel with other automatic or manual compactions in restricted cases
Summary:
This diff provides a framework for doing manual
compactions in parallel with other compactions. We now have a deque of manual compactions. We also pass manual compactions as an argument from RunManualCompactions down to
BackgroundCompactions, so that RunManualCompactions can be reentrant.
Parallelism is controlled by the two routines
ConflictingManualCompaction to allow/disallow new parallel/manual
compactions based on already existing ManualCompactions. In this diff, by default manual compactions still have to run exclusive of other compactions. However, by setting the compaction option, exclusive_manual_compaction to false, it is possible to run other compactions in parallel with a manual compaction. However, we are still restricted to one manual compaction per column family at a time. All of these restrictions will be relaxed in future diffs.
I will be adding more tests later.

Test Plan: Rocksdb regression + new tests + valgrind

Reviewers: igor, anthony, IslamAbdelRahman, kradhakrishnan, yhchiang, sdong

Reviewed By: sdong

Subscribers: yoshinorim, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D47973
2015-12-14 11:20:34 -08:00
Dmitri Smirnov
236fe21c92 Enable MS compiler warning c4244.
Mostly due to the fact that there are differences in sizes of int,long
  on 64 bit systems vs GNU.
2015-12-11 16:47:34 -08:00
agiardullo
84f98792d6 Transaction::SetWriteOptions()
Summary: Add support to change write options after creating a transaction.  This is needed for MongoRocks.

Test Plan: added test

Reviewers: sdong, rven, kradhakrishnan, IslamAbdelRahman, yhchiang

Reviewed By: yhchiang

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D51867
2015-12-11 16:08:25 -08:00
agiardullo
3bfd3d39a3 Use SST files for Transaction conflict detection
Summary:
Currently, transactions can fail even if there is no actual write conflict.  This is due to relying on only the memtables to check for write-conflicts.  Users have to tune memtable settings to try to avoid this, but it's hard to figure out exactly how to tune these settings.

With this diff, TransactionDB will use both memtables and SST files to determine if there are any write conflicts.  This relies on the fact that BlockBasedTable stores sequence numbers for all writes that happen after any open snapshot.  Also, D50295 is needed to prevent SingleDelete from disappearing writes (the TODOs in this test code will be fixed once the other diff is approved and merged).

Note that Optimistic transactions will still rely on tuning memtable settings as we do not want to read from SST while on the write thread.  Also, memtable settings can still be used to reduce how often TransactionDB needs to read SST files.

Test Plan: unit tests, db bench

Reviewers: rven, yhchiang, kradhakrishnan, IslamAbdelRahman, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb, yoshinorim

Differential Revision: https://reviews.facebook.net/D50475
2015-12-11 12:34:11 -08:00
Igor Canadi
64fa43843b Merge pull request #862 from ceph/wip-env
implement EnvMirror
2015-12-10 18:45:07 -08:00
Sage Weil
2074ddd625 env: add EnvMirror
This is an Env implementation that mirrors all storage-related methods on
two different backend Env's and verifies that they return the same
results (return status and read results).  This is useful for implementing
a new Env and verifying its correctness.

Signed-off-by: Sage Weil <sage@redhat.com>
2015-12-10 21:32:45 -05:00
charsyam
c30b499541 fix typos in comments 2015-12-11 01:54:48 +09:00
Siying Dong
fa3dbf203f Merge pull request #853 from Vaisman/enable_C4267_warning
Enable C4267 warning
2015-12-08 17:59:24 -08:00
agiardullo
e5c5f23814 Support marking snapshots for write-conflict checking - Take 2
Summary:
D51183 was reverted due to breaking the LITE build.

This diff is the same as D51183 but with a fix for the LITE BUILD(D51693)

Test Plan: run all unit tests

Reviewers: sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D51711
2015-12-08 16:47:31 -08:00
sdong
1d63c3d610 Revert "Support marking snapshots for write-conflict checking"
This reverts commit ec704aafdc for it broke RocksDB LITE build.
2015-12-08 09:27:17 -08:00
agiardullo
ec704aafdc Support marking snapshots for write-conflict checking
Summary:
D50475 enables using SST files for transaction write-conflict checking.  In order for this to work, we need to make sure not to compact out SingleDeletes when there is an earlier transaction snapshot(D50295).  If there is a long-held snapshot, this could reduce the benefit of the SingleDelete optimization.

This diff allows Transactions to mark snapshots as being used for write-conflict checking.  Then, during compaction, we will be able to optimize SingleDeletes better in the future.

This diff adds a flag to SnapshotImpl which is used by Transactions.  This diff also passes the earliest write-conflict snapshot's sequence number to CompactionIterator.  This diff does not actually change Compaction (after this diff is pushed, D50295 will be able to use this information).

Test Plan: no behavior change, ran existing tests

Reviewers: rven, kradhakrishnan, yhchiang, IslamAbdelRahman, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D51183
2015-12-07 19:40:51 -08:00