Summary:
Divide ReadBlockContents() to multiple sub-functions. Maintaining the input and intermediate data in a new class BlockFetcher.
I hope in general it makes the code easier to maintain.
Another motivation to do it is to clearly divide the logic before file reading and after file reading. The refactor will help us evaluate how can we make I/O async in the future.
Closes https://github.com/facebook/rocksdb/pull/3244
Differential Revision: D6520983
Pulled By: siying
fbshipit-source-id: 338d90bc0338472d46be7a7682028dc9114b12e9
Summary:
The current implementation of PinnableSlice move assignment have an issue #3163. We are moving away from it instead of try to get the move assignment right, since it is too tricky.
Closes https://github.com/facebook/rocksdb/pull/3164
Differential Revision: D6319201
Pulled By: yiwu-arbug
fbshipit-source-id: 8f3279021f3710da4a4caa14fd238ed2df902c48
Summary:
Move WritePreparedTxnDB from pessimistic_transaction_db.h to its own header, write_prepared_txn_db.h
Closes https://github.com/facebook/rocksdb/pull/3114
Differential Revision: D6220987
Pulled By: maysamyabandeh
fbshipit-source-id: 18893fb4fdc6b809fe117dabb544080f9b4a301b
Summary:
This PR also includes some cleanup, bugfixes and refactoring of the Java API. However these are really pre-cursors on the road to CompactionFilterFactory support.
Closes https://github.com/facebook/rocksdb/pull/1241
Differential Revision: D6012778
Pulled By: sagar0
fbshipit-source-id: 0774465940ee99001a78906e4fed4ef57068ad5c
Summary:
Update Compaction/Flush to support WritePreparedTxnDB: Add SnapshotChecker which is a proxy to query WritePreparedTxnDB::IsInSnapshot. Pass SnapshotChecker to DBImpl on WritePreparedTxnDB open. CompactionIterator use it to check if a key has been committed and if it is visible to a snapshot. In CompactionIterator:
* check if key has been committed. If not, output uncommitted keys AS-IS.
* use SnapshotChecker to check if key is visible to a snapshot when in need.
* do not output key with seq = 0 if the key is not committed.
Closes https://github.com/facebook/rocksdb/pull/2926
Differential Revision: D5902907
Pulled By: yiwu-arbug
fbshipit-source-id: 945e037fdf0aa652dc5ba0ad879461040baa0320
Summary:
Remove cassandra tombstone when reaching the max compaction level (full merge). if all columns collected key will be removed in next compaction via compaction filter
Closes https://github.com/facebook/rocksdb/pull/2791
Reviewed By: sagar0
Differential Revision: D5722465
Pulled By: wpc
fbshipit-source-id: 61e9898a5686551653a16383255aeaab3197e65e
Summary:
This patch splits Commit and Prepare into lock-related logic and db-write-related logic. It moves lock-related logic to PessimisticTransaction to be reused by all children classes and movies the existing impl of db-write-related to PrepareInternal, CommitSingleInternal, and CommitInternal in WriteCommittedTxnImpl.
Closes https://github.com/facebook/rocksdb/pull/2691
Differential Revision: D5569464
Pulled By: maysamyabandeh
fbshipit-source-id: d1b8698e69801a4126c7bc211745d05c636f5325
Summary:
This opens space for the new implementations of TransactionDBImpl such as WritePreparedTxnDBImpl that has a different policy of how to write to DB.
Closes https://github.com/facebook/rocksdb/pull/2689
Differential Revision: D5568918
Pulled By: maysamyabandeh
fbshipit-source-id: f7eac866e175daf3793ae79da108f65cc7dc7b25
Summary:
This patch refactors TransactionImpl by separating the logic for pessimistic concurrency control from the implementation of how to write the data to rocksdb. The existing implementation is named WriteCommittedTxnImpl as it writes committed data to the db. A template named WritePreparedTxnImpl is also added which will be later completed to provide a an alternative implementation.
Closes https://github.com/facebook/rocksdb/pull/2676
Differential Revision: D5549998
Pulled By: maysamyabandeh
fbshipit-source-id: 16298e86b43ca4849324c1f35c731913c6d17bec
Summary:
* Dump blob db options to info log
* Remove BlobDBOptionsImpl to disallow dynamic cast *BlobDBOptions into *BlobDBOptionsImpl. Move options there to be constants or into BlobDBOptions. The dynamic cast is broken after #2645
* Change some of the default options
* Remove blob_db_options.min_blob_size, which is unimplemented. Will implement it soon.
Closes https://github.com/facebook/rocksdb/pull/2671
Differential Revision: D5529912
Pulled By: yiwu-arbug
fbshipit-source-id: dcd58ca981db5bcc7f123b65a0d6f6ae0dc703c7
Summary:
Introducing blob_db::TTLExtractor to replace extract_ttl_fn. The TTL
extractor can be use to extract TTL from keys insert with Put or
WriteBatch. Change over existing extract_ttl_fn are:
* If value is changed, it will be return via std::string* (rather than Slice*). With Slice* the new value has to be part of the existing value. With std::string* the limitation is removed.
* It can optionally return TTL or expiration.
Other changes in this PR:
* replace `std::chrono::system_clock` with `Env::NowMicros` so that I can mock time in tests.
* add several TTL tests.
* other minor naming change.
Closes https://github.com/facebook/rocksdb/pull/2659
Differential Revision: D5512627
Pulled By: yiwu-arbug
fbshipit-source-id: 0dfcb00d74d060b8534c6130c808e4d5d0a54440
Summary:
Major changes in this PR:
* Implement CassandraCompactionFilter to remove expired columns and rows (if all column expired)
* Move cassandra related code from utilities/merge_operators/cassandra to utilities/cassandra/*
* Switch to use shared_ptr<> from uniqu_ptr for Column membership management in RowValue. Since columns do have multiple owners in Merge and GC process, use shared_ptr helps make RowValue immutable.
* Rename cassandra_merge_test to cassandra_functional_test and add two TTL compaction related tests there.
Closes https://github.com/facebook/rocksdb/pull/2588
Differential Revision: D5430010
Pulled By: wpc
fbshipit-source-id: 9566c21e06de17491d486a68c70f52d501f27687
Summary:
target `utilities/merge_operators/cassandra/test_utils.d' given more than once in the same rule
remove the duplicate one
Closes https://github.com/facebook/rocksdb/pull/2542
Differential Revision: D5379570
Pulled By: lightmark
fbshipit-source-id: 353f38d085e9f627c1b3c53acef7a2c4bc71014d
Summary:
1. The buckifier script assume each test "foo" comes with a .cc file of the same name (i.e. foo.cc). Update cassandra tests to follow this pattern so that the buckifier script can recognize them.
2. add blob_db_test
Closes https://github.com/facebook/rocksdb/pull/2506
Differential Revision: D5331517
Pulled By: yiwu-arbug
fbshipit-source-id: 86f3eba471fc621186ab44cbd073b6162cde8e57
Summary:
This PR adds support for encrypting data stored by RocksDB when written to disk.
It adds an `EncryptedEnv` override of the `Env` class with matching overrides for sequential&random access files.
The encryption itself is done through a configurable `EncryptionProvider`. This class creates is asked to create `BlockAccessCipherStream` for a file. This is where the actual encryption/decryption is being done.
Currently there is a Counter mode implementation of `BlockAccessCipherStream` with a `ROT13` block cipher (NOTE the `ROT13` is for demo purposes only!!).
The Counter operation mode uses an initial counter & random initialization vector (IV).
Both are created randomly for each file and stored in a 4K (default size) block that is prefixed to that file. The `EncryptedEnv` implementation is such that clients of the `Env` class do not see this prefix (nor data, nor in filesize).
The largest part of the prefix block is also encrypted, and there is room left for implementation specific settings/values/keys in there.
To test the encryption, the `DBTestBase` class has been extended to consider a new environment variable called `ENCRYPTED_ENV`. If set, the test will setup a encrypted instance of the `Env` class to use for all tests.
Typically you would run it like this:
```
ENCRYPTED_ENV=1 make check_some
```
There is also an added test that checks that some data inserted into the database is or is not "visible" on disk. With `ENCRYPTED_ENV` active it must not find plain text strings, with `ENCRYPTED_ENV` unset, it must find the plain text strings.
Closes https://github.com/facebook/rocksdb/pull/2424
Differential Revision: D5322178
Pulled By: sdwilsh
fbshipit-source-id: 253b0a9c2c498cc98f580df7f2623cbf7678a27f
Summary:
Improve write buffer manager in several ways:
1. Size is tracked when arena block is allocated, rather than every allocation, so that it can better track actual memory usage and the tracking overhead is slightly lower.
2. We start to trigger memtable flush when 7/8 of the memory cap hits, instead of 100%, and make 100% much harder to hit.
3. Allow a cache object to be passed into buffer manager and the size allocated by memtable can be costed there. This can help users have one single memory cap across block cache and memtable.
Closes https://github.com/facebook/rocksdb/pull/2350
Differential Revision: D5110648
Pulled By: siying
fbshipit-source-id: b4238113094bf22574001e446b5d88523ba00017
Summary:
This is a manual commit of this PR:
Retire InMemoryEnv in favor of MockEnv #2082
With MockEnv doing the same yet being more mature, InMemoryEnv is redundant.
Reviewed By: IslamAbdelRahman
Differential Revision: D5162323
fbshipit-source-id: 59fd0082a891dc99cc531e4da9d68bf891eae3f5
Summary:
This fixes a compilation failure on Linux when the system libc is not
glibc. jemalloc's configure script incorrectly assumes that glibc is
always used on Linux systems, producing glibc-style signatures; when
the system libc is e.g. musl, the following error is observed:
```
[ 0%] Building CXX object CMakeFiles/rocksdb.dir/db/db_impl.cc.o
In file included from /go/src/github.com/cockroachdb/cockroach/c-deps/rocksdb.src/table/block.h:19:0,
from /go/src/github.com/cockroachdb/cockroach/c-deps/rocksdb.src/db/db_impl.cc:77:
/x-tools/x86_64-unknown-linux-musl/x86_64-unknown-linux-musl/sysroot/usr/include/malloc.h:19:8: error: declaration of 'size_t malloc_usable_size(void*)' has a different exception specifier
size_t malloc_usable_size(void *);
^~~~~~~~~~~~~~~~~~
In file included from /go/src/github.com/cockroachdb/cockroach/c-deps/rocksdb.src/db/db_impl.cc:20:0:
/go/native/x86_64-unknown-linux-musl/jemalloc/include/jemalloc/jemalloc.h:78:33: note: from previous declaration 'size_t malloc_usable_size(void*) throw ()'
# define je_malloc_usable_size malloc_usable_size
^
/go/native/x86_64-unknown-linux-musl/jemalloc/include/jemalloc/jemalloc.h:239:41: note: in expansion of macro 'je_malloc_usable_size'
JEMALLOC_EXPORT size_t JEMALLOC_NOTHROW je_malloc_usable_size(
^~~~~~~~~~~~~~~~~~~~~
CMakeFiles/rocksdb.dir/build.make:350: recipe for target 'CMakeFiles/rocksdb.dir/db/db_impl.cc.o' failed
```
This works around the issue by rearranging the sources such that
jemalloc's headers are never in the same scope as the system's malloc
header. The jemalloc issue has been reported as well, see:
https://github.com/jemalloc/jemalloc/issues/778.
cc tschottdorf
Closes https://github.com/facebook/rocksdb/pull/2188
Differential Revision: D5163048
Pulled By: siying
fbshipit-source-id: c553125458892def175c1be5682b0330d80b2a0d
Summary:
Blob db rely on base db returning sequence number through write batch after DB::Write(). However after recent changes to the write path, DB::Writ()e no longer return sequence number in some cases. Fixing it by have WriteBatchInternal::InsertInto() always encode sequence number into write batch.
Stacking on #2375.
Closes https://github.com/facebook/rocksdb/pull/2385
Differential Revision: D5148358
Pulled By: yiwu-arbug
fbshipit-source-id: 8bda0aa07b9334ed03ed381548b39d167dc20c33
Summary:
Re-enable blob_db_test with some update:
* Commented out delay at the end of GC tests. Will update the logic later with sync point to properly trigger GC.
* Added some helper functions.
Also update make files to include blob_dump tool.
Closes https://github.com/facebook/rocksdb/pull/2375
Differential Revision: D5133793
Pulled By: yiwu-arbug
fbshipit-source-id: 95470b26d0c1f9592ba4b7637e027fdd263f425c
Summary:
Previously the Java implementation of `RocksDB#addFile` was both incomplete and not inline with the C++ API.
Rather than fix it, as I see that `rocksdb::DB::AddFile` is now deprecated in favour of `rocksdb::DB::IngestExternalFile`, I have removed the old broken implementation and implemented `RocksDB#ingestExternalFile`.
Closes https://github.com/facebook/rocksdb/issues/2261
Closes https://github.com/facebook/rocksdb/pull/2291
Differential Revision: D5061264
Pulled By: sagar0
fbshipit-source-id: 85df0899fa1b1fc3535175cac4f52353511d4104
Summary:
snprintf is in <stdio.h> and not in namespace std.
Closes https://github.com/facebook/rocksdb/pull/2287
Reviewed By: anirbanr-fb
Differential Revision: D5054752
Pulled By: yiwu-arbug
fbshipit-source-id: 356807ec38f3c7d95951cdb41f31a3d3ae0714d4
Summary:
- Introduced an include/ file dedicated to db-related debug functions to avoid making db.h more complex
- Added debugging function, `GetAllKeyVersions()`, to return a listing of internal data for a range of user keys. The new `struct KeyVersion` exposes data similar to internal key without exposing any internal type.
- Migrated the "ldb idump" subcommand to use this function
- The API takes an inclusive-exclusive range to match behavior of "ldb idump". This will be quite annoying for users who want to query a single user key's versions :(.
Closes https://github.com/facebook/rocksdb/pull/2232
Differential Revision: D4976007
Pulled By: ajkr
fbshipit-source-id: cab375da53a7595d6575af2b7e3b776aa3ad793e
Summary:
I'm going to add more DB tests for statistics as currently we have very few. I started a file dedicated to this purpose and moved the existing stats-specific tests there.
Closes https://github.com/facebook/rocksdb/pull/2211
Differential Revision: D4951558
Pulled By: ajkr
fbshipit-source-id: 05d11c35079c40ecabdfd2cf5556ccb761f694a4
Summary:
These code paths forked when checkpoint was introduced by copy/pasting the core backup logic. Over time they diverged and bug fixes were sometimes applied to one but not the other (like fix to include all relevant WALs for 2PC), or it required extra effort to fix both (like fix to forge CURRENT file). This diff reunites the code paths by extracting the core logic into a function, CreateCustomCheckpoint(), that is customizable via callbacks to implement both checkpoint and backup.
Related changes:
- flush_before_backup is now forcibly enabled when 2PC is enabled
- Extracted CheckpointImpl class definition into a header file. This is so the function, CreateCustomCheckpoint(), can be called by internal rocksdb code but not exposed to users.
- Implemented more functions in DummyDB/DummyLogFile (in backupable_db_test.cc) that are used by CreateCustomCheckpoint().
Closes https://github.com/facebook/rocksdb/pull/1932
Differential Revision: D4622986
Pulled By: ajkr
fbshipit-source-id: 157723884236ee3999a682673b64f7457a7a0d87
Summary:
1. Move universal compaction picker to separate files compaction_picker_universal.cc and compaction_picker_universal.h.
2. Rename some functions to make the code easier to understand.
3. Move leveled compaction picking code to a dedicated class, so that we we don't need to pass some common variable around when calling functions. It also allowed us to break down LevelCompactionPicker::PickCompaction() to smaller functions.
Closes https://github.com/facebook/rocksdb/pull/2100
Differential Revision: D4845948
Pulled By: siying
fbshipit-source-id: efa0ab4
Summary:
This is an effort to club all string related utility functions into one common place, in string_util, so that it is easier for everyone to know what string processing functions are available. Right now they seem to be spread out across multiple modules, like logging and options_helper.
Check the sub-commits for easier reviewing.
Closes https://github.com/facebook/rocksdb/pull/2094
Differential Revision: D4837730
Pulled By: sagar0
fbshipit-source-id: 344278a
Summary:
Move some files under util/ to new directories env/, monitoring/ options/ and cache/
Closes https://github.com/facebook/rocksdb/pull/2090
Differential Revision: D4833681
Pulled By: siying
fbshipit-source-id: 2fd8bef
Summary:
db_impl.cc is too large to manage. Divide db_impl.cc into db/db_impl.cc, db/db_impl_compaction_flush.cc, db/db_impl_files.cc, db/db_impl_open.cc and db/db_impl_write.cc.
Closes https://github.com/facebook/rocksdb/pull/2095
Differential Revision: D4838188
Pulled By: siying
fbshipit-source-id: c5f3059
Summary:
I've needed Env timing measurements a few times now, so finally built something for it.
Closes https://github.com/facebook/rocksdb/pull/2073
Differential Revision: D4811231
Pulled By: ajkr
fbshipit-source-id: 218a249
Summary:
It is confusing to have auto_roll_logger to stay under db/, which has nothing to do with database. Move filename together as it is a dependency.
Closes https://github.com/facebook/rocksdb/pull/2080
Differential Revision: D4821141
Pulled By: siying
fbshipit-source-id: ca7d768
Summary:
This adds almost all missing options to RocksJava
Closes https://github.com/facebook/rocksdb/pull/2039
Differential Revision: D4779991
Pulled By: siying
fbshipit-source-id: 4a1bf28
Summary:
Separate the platform dependent tests from external_sst_file_test. Only those tests need to run on platforms like OSX
Closes https://github.com/facebook/rocksdb/pull/1923
Differential Revision: D4622461
Pulled By: siying
fbshipit-source-id: d2d6f04
Summary:
Separate a smal subset of tests in DBTest to DBBasicTest. Tests in DBTest don't have to run in CI tests on platforms like OSX, as long as they are covered by Linux.
Closes https://github.com/facebook/rocksdb/pull/1924
Differential Revision: D4616702
Pulled By: siying
fbshipit-source-id: 13e6549
Summary:
merger.h was always a confusing name for me, simply give the file a better name
Closes https://github.com/facebook/rocksdb/pull/1836
Differential Revision: D4505357
Pulled By: IslamAbdelRahman
fbshipit-source-id: 07b28d8
Summary:
The Env registration framework supports registering client Envs and selecting which one to instantiate according to a text field. This enabled things like adding the -env_uri argument to db_bench, so the same binary could be reused with different Envs just by changing CLI config.
Now this problem has come up again in a non-Env context, as I want to instantiate a client Statistics implementation from db_bench, which is configured entirely via text parameters. Also, in the future we may wish to use it for deserializing client objects when loading OPTIONS file.
This diff generalizes the Env registration logic to work with arbitrary types.
- Generalized registration and instantiation code by templating them
- The entire implementation is in a header file as that's Google style guide's recommendation for template definitions
- Pattern match with std::regex_match rather than checking prefix, which was the previous behavior
- Rename functions/files to be non-Env-specific
Closes https://github.com/facebook/rocksdb/pull/1776
Differential Revision: D4421933
Pulled By: ajkr
fbshipit-source-id: 34647d1
Summary:
Iterator should be in corrupted status if merge operator return false.
Also add test to make sure if max_successive_merges is hit during write,
data will not be lost.
Closes https://github.com/facebook/rocksdb/pull/1665
Differential Revision: D4322695
Pulled By: yiwu-arbug
fbshipit-source-id: b327b05
Summary:
Now that we have userspace persisted cache, we don't need flashcache anymore.
Closes https://github.com/facebook/rocksdb/pull/1588
Differential Revision: D4245114
Pulled By: igorcanadi
fbshipit-source-id: e2c1c72
Summary:
Changes in the diff
API changes:
- Introduce IngestExternalFile to replace AddFile (I think this make the API more clear)
- Introduce IngestExternalFileOptions (This struct will encapsulate the options for ingesting the external file)
- Deprecate AddFile() API
Logic changes:
- If our file overlap with the memtable we will flush the memtable
- We will find the first level in the LSM tree that our file key range overlap with the keys in it
- We will find the lowest level in the LSM tree above the the level we found in step 2 that our file can fit in and ingest our file in it
- We will assign a global sequence number to our new file
- Remove AddFile restrictions by using global sequence numbers
Other changes:
- Refactor all AddFile logic to be encapsulated in ExternalSstFileIngestionJob
Test Plan:
unit tests (still need to add more)
addfile_stress (https://reviews.facebook.net/D65037)
Reviewers: yiwu, andrewkr, lightmark, yhchiang, sdong
Reviewed By: sdong
Subscribers: jkedgar, hcz, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D65061
Summary:
This diff introduces RangeDelAggregator, which takes ownership of iterators
provided to it via AddTombstones(). The tombstones are organized in a two-level
map (snapshot stripe -> begin key -> tombstone). Tombstone creation avoids data
copy by holding Slices returned by the iterator, which remain valid thanks to pinning.
For compaction, we create a hierarchical range tombstone iterator with structure
matching the iterator over compaction input data. An aggregator based on that
iterator is used by CompactionIterator to determine which keys are covered by
range tombstones. In case of merge operand, the same aggregator is used by
MergeHelper. Upon finishing each file in the compaction, relevant range tombstones
are added to the output file's range tombstone metablock and file boundaries are
updated accordingly.
To check whether a key is covered by range tombstone, RangeDelAggregator::ShouldDelete()
considers tombstones in the key's snapshot stripe. When this function is used outside of
compaction, it also checks newer stripes, which can contain covering tombstones. Currently
the intra-stripe check involves a linear scan; however, in the future we plan to collapse ranges
within a stripe such that binary search can be used.
RangeDelAggregator::AddToBuilder() adds all range tombstones in the table's key-range
to a new table's range tombstone meta-block. Since range tombstones may fall in the gap
between files, we may need to extend some files' key-ranges. The strategy is (1) first file
extends as far left as possible and other files do not extend left, (2) all files extend right
until either the start of the next file or the end of the last range tombstone in the gap,
whichever comes first.
One other notable change is adding release/move semantics to ScopedArenaIterator
such that it can be used to transfer ownership of an arena-allocated iterator, similar to
how unique_ptr is used for malloc'd data.
Depends on D61473
Test Plan: compaction_iterator_test, mock_table, end-to-end tests in D63927
Reviewers: sdong, IslamAbdelRahman, wanning, yhchiang, lightmark
Reviewed By: lightmark
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D62205
Summary: Use ImmutableDBOptions/MutableDBOptions internally and DBOptions only for user-facing APIs. MutableDBOptions is barely a placeholder for now. I'll start to move options to MutableDBOptions in following diffs.
Test Plan:
make all check
Reviewers: yhchiang, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D64065
Summary: There's no reference to ImmutableCFOptions elsewhere in /include/rocksdb. ImmutableCFOptions was introduced in this commit (5665e5e285) but later its reference in /include/rocksdb/table.h is removed.
Test Plan:
make all check
Reviewers: IslamAbdelRahman, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: yhchiang, andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D63177
Summary:
This diff split ThreadPool to
-ThreadPool (abstract interface exposed in include/rocksdb/threadpool.h)
-ThreadPoolImpl (actual implementation in util/threadpool_imp.h)
This allow us to expose ThreadPool to the user so we can use it as an option later
Test Plan: existing unit tests
Reviewers: andrewkr, yiwu, yhchiang, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D62085
Summary:
Clock-based cache implemenetation aim to have better concurreny than
default LRU cache. See inline comments for implementation details.
Test Plan:
Update cache_test to run on both LRUCache and ClockCache. Adding some
new tests to catch some of the bugs that I fixed while implementing the
cache.
Reviewers: kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D61647
Summary:
This is a proof of concept of a RocksDB blob log file. The actual value of the Put() is appended to a blob log using normal data block format, and the handle of the block is written as the value of the key in RocksDB.
The prototype only supports Put() and Get(). It doesn't support DB restart, garbage collection, Write() call, iterator, snapshots, etc.
Test Plan: Add unit tests.
Reviewers: arahut
Reviewed By: arahut
Subscribers: kradhakrishnan, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D61485
Summary: Implement a time series database that supports DateTieredCompactionStrategy. It wraps a db object and separate SST files in different column families (time windows).
Test Plan: Add `date_tiered_test`.
Reviewers: dhruba, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D61653
Summary: Add a utility function that trigger necessary full compaction and put output to the correct level by looking at new options and old options.
Test Plan: Add unit tests for it.
Reviewers: andrewkr, igor, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: muthu, sumeet, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D60783
Summary:
Experiments on column-aware encodings. Supported features: 1) extract data blocks from SST file and encode with specified encodings; 2) Decode encoded data back into row format; 3) Directly extract data blocks and write in row format (without prefix encoding); 4) Get column distribution statistics for column format; 5) Dump data blocks separated by columns in human-readable format.
There is still on-going work on this diff. More refactoring is necessary.
Test Plan: Wrote tests in `column_aware_encoding_test.cc`. More tests should be added.
Reviewers: sdong
Reviewed By: sdong
Subscribers: arahut, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D60027
Summary:
The patch is a continuation of part 5. It glues the abstraction for
file layout and metadata, and flush out the implementation of the API. It
adds unit tests for the implementation.
Test Plan: Run unit tests
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D57549
Summary:
TickersNameMap is not consistent with Tickers enum.
this cause us to report wrong statistics and sometimes to access TickersNameMap outside it's boundary causing crashes (in Fb303 statistics)
Test Plan: added new unit test
Reviewers: sdong, kradhakrishnan
Reviewed By: kradhakrishnan
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D61083
Summary:
Fix flush not being commit while writing manifest, which is a recent bug introduced by D60075.
The issue:
# Options.max_background_flushes > 1
# Background thread A pick up a flush job, flush, then commit to manifest. (Note that mutex is released before writing manifest.)
# Background thread B pick up another flush job, flush. When it gets to `MemTableList::InstallMemtableFlushResults`, it notices another thread is commiting, so it quit.
# After the first commit, thread A doesn't double check if there are more flush result need to commit, leaving the second flush uncommitted.
Test Plan: run the test. Also verify the new test hit deadlock without the fix.
Reviewers: sdong, igor, lightmark
Reviewed By: lightmark
Subscribers: andrewkr, omegaga, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D60969
Summary:
Persistent cache tier is the tier abstraction that can work for any block
device based device mounted on a file system. The design/implementation can
handle any generic block device.
Any generic block support is achieved by generalizing the access patten as
{io-size, q-depth, direct-io/buffered}.
We have specifically tested and adapted the IO path for NVM and SSD.
Persistent cache tier consists of there parts :
1) File layout
Provides the implementation for handling IO path for reading and writing data
(key/value pair).
2) Meta-data
Provides the implementation for handling the index for persistent read cache.
3) Implementation
It binds (1) and (2) and flushed out the PersistentCacheTier interface
This patch provides implementation for (1)(2). Follow up patch will provide (3)
and tests.
Test Plan: Compile and run check
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D57117
Summary: Refactor cache.cc so that I can plugin clock cache (D55581). Mainly move `ShardedCache` to separate file, move `LRUHandle` back to cache.cc and rename it lru_cache.cc.
Test Plan:
make check -j64
Reviewers: lightmark, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D59655
Summary:
When write stalls because of auto compaction is disabled, or stop write trigger is reached,
user may change these two options to unblock writes. Unfortunately we had issue where the write
thread will block the attempt to persist the options, thus creating a deadlock. This diff
fix the issue and add two test cases to detect such deadlock.
Test Plan:
Run unit tests.
Also, revert db_impl.cc to master (but don't revert `DBImpl::BackgroundCompaction:Finish` sync point) and run db_options_test. Both tests should hit deadlock.
Reviewers: sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D60627
Summary: In D33849 we updated Makefile to generate .d files for all .cc sources. Since we have more types of source files now, this needs to be updated so that this mechanism can work for new files.
Test Plan: change a dependent .h file, re-make and see if .o file is recompiled.
Reviewers: sdong, andrewkr
Reviewed By: andrewkr
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D60591
Summary:
DB::AddFile() right now always add the ingested file to L0
update the logic to add the file to the lowest possible level
Test Plan: unit tests
Reviewers: jkedgar, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, yoshinorim
Differential Revision: https://reviews.facebook.net/D59637
Summary: It confuses some compilers to have slice.cc under multiple directories. Merge them.
Test Plan: Run existing tests
Reviewers: andrewkr, yhchiang, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D59409
Summary: AFIK, options builder is not used by anyone. Remove it.
Test Plan: Run all existing tests.
Reviewers: IslamAbdelRahman, andrewkr, igor
Reviewed By: igor
Subscribers: leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D59319
Summary:
This provides provides an implementation of PersistentCacheTier that is
specialized for RAM. This tier does not persist data though.
Why do we need this tier ?
This is ideal as tier 0. This tier can host data that is too hot.
Why can't we use Cache variants ?
Yes you can use them instead. This tier can potentially outperform BlockCache
in RAW mode by virtue of compression and compressed cache in block cache doesn't
seem very popular. Potentially this tier can be modified to under stand the
disadvantage of the tier below and retain data that the tier below is bad at
handling (for example index and bloom data that is huge in size)
Test Plan: Run unit tests added
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D57069
Summary:
This diff provides the basic interface definitions of persistent read
cache system
PersistentCacheOptions captures the persistent read cache options used to
configure and control the system
PersistentCacheTier provides the basic building block for constructing tiered
cache
PersistentTieredCache provides a logical abstraction of tiers of cache layered
over one another
Test Plan: Compile
Reviewers: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D57051
Summary:
Extracted basic Env-related tests from mock_env_test and memenv_test into a
parameterized test for Envs: env_basic_test.
Depends on D58449. (The dependency is here only so I can keep this series of
diffs in a chain -- there is no dependency on that diff's code.)
Test Plan: ran tests
Reviewers: IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D58635
Summary:
This enables configurable Envs without recompiling. For example, my
next diff will make env_test test an Env created by NewEnvFromUri(). Then,
users can determine which Env is tested simply by providing the URI for
NewEnvFromUri() (e.g., through a CLI argument or environment variable).
The registration process allows us to register any Env that is linked with the
RocksDB library, so we can register our internal Envs as well.
The registration code is inspired by our internal InitRegistry.
Test Plan: new unit test
Reviewers: IslamAbdelRahman, lightmark, ldemailly, sdong
Reviewed By: sdong
Subscribers: leveldb, dhruba, andrewkr
Differential Revision: https://reviews.facebook.net/D58449
Summary:
This patch allows db_bench to initialize it's RocksDB Options via a
options file, specified by the --options_file flag. Note that if
--options_file flag is set, then it has higher priority than the
command-line argument.
Test Plan: db_bench_tool_test
Reviewers: sdong, IslamAbdelRahman, kradhakrishnan, yiwu, andrewkr
Reviewed By: andrewkr
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D58533
Summary: Deprecate this one option and delete code and tests that are now superfluous.
Test Plan: all tests pass
Reviewers: igor, yhchiang, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: msalib, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D55317
Summary:
Introduce MaxOperator a simple merge operator that return the max of all operands.
This merge operand help me in benchmarking
Test Plan: Add new unitttests
Reviewers: sdong, andrewkr, yhchiang
Reviewed By: yhchiang
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D57873
Summary:
This is a part of effort to reduce the size of db_test.cc. We move the following tests to a separate file `db_io_failure_test.cc`:
* DropWrites
* DropWritesFlush
* NoSpaceCompactRange
* NonWritableFileSystem
* ManifestWriteError
* PutFailsParanoid
Test Plan: Run `make check` to see if the tests are working properly.
Reviewers: sdong, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D58341
Summary:
Added a new abstraction to cache page to RocksDB designed for the read
cache use.
RocksDB current block cache is more of an object cache. For the persistent read cache
project, what we need is a page cache equivalent. This changes adds a cache
abstraction to RocksDB to cache pages called PersistentCache. PersistentCache can cache
uncompressed pages or raw pages (content as in filesystem). The user can
choose to operate PersistentCache either in COMPRESSED or UNCOMPRESSED mode.
Blame Rev:
Test Plan: Run unit tests
Reviewers: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D55707
Conditionally retrofit thread_posix for use with std::thread
and reuse the same logic. Posix users continue using Posix interfaces.
Enable XPRESS compression in test runs.
Fix master introduced signed/unsigned mismatch.
Summary:
Consider the following WAL with 4 batch entries prefixed with their sequence at time of memtable insert.
[1: BEGIN_PREPARE, PUT, PUT, PUT, PUT, END_PREPARE(a)]
[1: BEGIN_PREPARE, PUT, PUT, PUT, PUT, END_PREPARE(b)]
[4: COMMIT(a)]
[7: COMMIT(b)]
The first two batches do not consume any sequence numbers so are both prefixed with seq=1.
For 2pc commit, memtable insertion takes place before COMMIT batch is written to WAL.
We can see that sequence number consumption takes place between WAL entries giving us the seemingly sparse sequence prefix for WAL entries.
This is a valid WAL.
Because with 2PC markers one WriteBatch points to another batch containing its inserts a writebatch can consume more or less sequence numbers than the number of sequence consuming entries that it contains.
We can see that, given the entries in the WAL, 6 sequence ids were consumed. Yet on recovery the maximum sequence consumed would be 7 + 3 (the number of sequence numbers consumed by COMMIT(b))
So, now upon recovery we must track the actual consumption of sequence numbers.
In the provided scenario there will be no sequence gaps, but it is possible to produce a sequence gap. This should not be a problem though. correct?
Test Plan: provided test.
Reviewers: sdong
Subscribers: andrewkr, leveldb, dhruba, hermanlee4
Differential Revision: https://reviews.facebook.net/D57645
Summary:
For testing backups, we needed an Env that is fully isolated from other
Envs on the same machine. Our in-memory Envs (MockEnv and InMemoryEnv) were
insufficient because they don't implement most directory operations.
This diff introduces a new Env, "ChrootEnv", that translates paths such that the
chroot directory appears to be the root directory. This way, multiple Envs can
be isolated in the filesystem by using different chroot directories. Since we
use the filesystem, all directory operations are trivially supported.
Test Plan:
I parameterized the existing EnvPosixTest so it runs tests on ChrootEnv
except the ioctl-related cases.
Reviewers: sdong, lightmark, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D57543
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
Summary: similar to D52809 add option to exclude zero counters.
Test Plan:
[yiwu@dev4504.prn1 ~/rocksdb] ./iostats_context_test
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from IOStatsContextTest
[ RUN ] IOStatsContextTest.ToString
[ OK ] IOStatsContextTest.ToString (0 ms)
[----------] 1 test from IOStatsContextTest (0 ms total)
[----------] Global test environment tear-down
[==========] 1 test from 1 test case ran. (0 ms total)
[ PASSED ] 1 test.
Reviewers: anthony, yhchiang, andrewkr, IslamAbdelRahman, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D54591
Summary:
Remove obolete references to files in src.mk
Fix incorrect path for reference in source.mk
Test Plan: Ran build to ensure changes do not break anything.
Reviewers: leveldb, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D53733
Summary:
Add a new class SstFileTracker that will be notified whenever a DB add/delete/move and sst file, it will also replace DeleteScheduler
SstFileTracker can be used later to abort writes when we exceed a specific size
Test Plan: unit tests
Reviewers: rven, anthony, yhchiang, sdong
Reviewed By: sdong
Subscribers: igor, lovro, march, dhruba
Differential Revision: https://reviews.facebook.net/D50469
Summary:
I split the db-specific test points out into a separate file under db/
directory. There were also a few bugs to fix in xfunc.{h,cc} that prevented it
from compiling previously; see https://reviews.facebook.net/D36825.
Test Plan:
compilation works now, below command works, will also run "make xfunc".
$ make check ROCKSDB_XFUNC_TEST='managed_new' tests-regexp='DBTest' -j32
Reviewers: sdong, yhchiang
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D53343
Summary:
This diff adds support for concurrent adds to the skiplist memtable
implementations. Memory allocation is made thread-safe by the addition of
a spinlock, with small per-core buffers to avoid contention. Concurrent
memtable writes are made via an additional method and don't impose a
performance overhead on the non-concurrent case, so parallelism can be
selected on a per-batch basis.
Write thread synchronization is an increasing bottleneck for higher levels
of concurrency, so this diff adds --enable_write_thread_adaptive_yield
(default off). This feature causes threads joining a write batch
group to spin for a short time (default 100 usec) using sched_yield,
rather than going to sleep on a mutex. If the timing of the yield calls
indicates that another thread has actually run during the yield then
spinning is avoided. This option improves performance for concurrent
situations even without parallel adds, although it has the potential to
increase CPU usage (and the heuristic adaptation is not yet mature).
Parallel writes are not currently compatible with
inplace updates, update callbacks, or delete filtering.
Enable it with --allow_concurrent_memtable_write (and
--enable_write_thread_adaptive_yield). Parallel memtable writes
are performance neutral when there is no actual parallelism, and in
my experiments (SSD server-class Linux and varying contention and key
sizes for fillrandom) they are always a performance win when there is
more than one thread.
Statistics are updated earlier in the write path, dropping the number
of DB mutex acquisitions from 2 to 1 for almost all cases.
This diff was motivated and inspired by Yahoo's cLSM work. It is more
conservative than cLSM: RocksDB's write batch group leader role is
preserved (along with all of the existing flush and write throttling
logic) and concurrent writers are blocked until all memtable insertions
have completed and the sequence number has been advanced, to preserve
linearizability.
My test config is "db_bench -benchmarks=fillrandom -threads=$T
-batch_size=1 -memtablerep=skip_list -value_size=100 --num=1000000/$T
-level0_slowdown_writes_trigger=9999 -level0_stop_writes_trigger=9999
-disable_auto_compactions --max_write_buffer_number=8
-max_background_flushes=8 --disable_wal --write_buffer_size=160000000
--block_size=16384 --allow_concurrent_memtable_write" on a two-socket
Xeon E5-2660 @ 2.2Ghz with lots of memory and an SSD hard drive. With 1
thread I get ~440Kops/sec. Peak performance for 1 socket (numactl
-N1) is slightly more than 1Mops/sec, at 16 threads. Peak performance
across both sockets happens at 30 threads, and is ~900Kops/sec, although
with fewer threads there is less performance loss when the system has
background work.
Test Plan:
1. concurrent stress tests for InlineSkipList and DynamicBloom
2. make clean; make check
3. make clean; DISABLE_JEMALLOC=1 make valgrind_check; valgrind db_bench
4. make clean; COMPILE_WITH_TSAN=1 make all check; db_bench
5. make clean; COMPILE_WITH_ASAN=1 make all check; db_bench
6. make clean; OPT=-DROCKSDB_LITE make check
7. verify no perf regressions when disabled
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, IslamAbdelRahman, anthony, yhchiang, rven, sdong, guyg8, kradhakrishnan, dhruba
Differential Revision: https://reviews.facebook.net/D50589
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>
Summary: This patch moves all posix thread logic to a separate library.
The motivation is to allow another environments to easily reuse posix
threads. HDFS wraps already posix threads; this split would simplify
this code.
Test Plan: No new functionality is added to posix Env or the threading
library, thus the current tests should suffice.
Summary:
This diff is 1/3 in a sequence that introduces a skip list optimized for
a key that is a freshly-allocated const char*. The diff is broken into
pieces to make it easier to review. This piece only introduces the new
type by copying the existing SkipList, with mechanical naming changes
and reformatting.
Test Plan: new unit test
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D51279
Summary: forward_iterator_bench is not stable enough for build. Remove it for now.
Test Plan: Build it with both of CLANG and non-CLANG and make sure it builds.
Reviewers: rven, kradhakrishnan, anthony, yhchiang, igor, IslamAbdelRahman
Reviewed By: igor, IslamAbdelRahman
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D50991
Summary:
Under a tailing workload, there were increased block cache
misses when a memtable was flushed because we were rebuilding iterators
in that case since the version set changed. This was exacerbated in the
case of iterate_upper_bound, since file iterators which were over the
iterate_upper_bound would have been deleted and are now brought back as
part of the Rebuild, only to be deleted again. We now renew the iterators
and only build iterators for files which are added and delete file
iterators for files which are deleted.
Refer to https://reviews.facebook.net/D50463 for previous version
Test Plan: DBTestTailingIterator.TailingIteratorTrimSeekToNext
Reviewers: anthony, IslamAbdelRahman, igor, tnovak, yhchiang, sdong
Reviewed By: sdong
Subscribers: yhchiang, march, dhruba, leveldb, lovro
Differential Revision: https://reviews.facebook.net/D50679
Summary:
This patch adds OptionsUtil::LoadOptionsFromFile() and
OptionsUtil::LoadLatestOptionsFromDB(), which allow developers
to construct DBOptions and ColumnFamilyOptions from a RocksDB
options file. Note that most pointer-typed options such as
merge_operator will not be constructed.
With this API, developers no longer need to remember all the
options in order to reopen an existing rocksdb instance like
the following:
DBOptions db_options;
std::vector<std::string> cf_names;
std::vector<ColumnFamilyOptions> cf_opts;
// Load primitive-typed options from an existing DB
OptionsUtil::LoadLatestOptionsFromDB(
dbname, &db_options, &cf_names, &cf_opts);
// Initialize necessary pointer-typed options
cf_opts[0].merge_operator.reset(new MyMergeOperator());
...
// Construct the vector of ColumnFamilyDescriptor
std::vector<ColumnFamilyDescriptor> cf_descs;
for (size_t i = 0; i < cf_opts.size(); ++i) {
cf_descs.emplace_back(cf_names[i], cf_opts[i]);
}
// Open the DB
DB* db = nullptr;
std::vector<ColumnFamilyHandle*> cf_handles;
auto s = DB::Open(db_options, dbname, cf_descs,
&handles, &db);
Test Plan:
Augment existing tests in column_family_test
options_test
db_test
Reviewers: igor, IslamAbdelRahman, sdong, anthony
Reviewed By: anthony
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D49095
Summary:
This patch allows rocksdb to persist options into a file on
DB::Open, SetOptions, and Create / Drop ColumnFamily.
Options files are created under the same directory as the rocksdb
instance.
In addition, this patch also adds a fail_if_missing_options_file in DBOptions
that makes any function call return non-ok status when it is not able to
persist options properly.
// If true, then DB::Open / CreateColumnFamily / DropColumnFamily
// / SetOptions will fail if options file is not detected or properly
// persisted.
//
// DEFAULT: false
bool fail_if_missing_options_file;
Options file names are formatted as OPTIONS-<number>, and RocksDB
will always keep the latest two options files.
Test Plan:
Add options_file_test.
options_test
column_family_test
Reviewers: igor, IslamAbdelRahman, sdong, anthony
Reviewed By: anthony
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48285
Summary:
Using a TLS random instance for skiplist makes it smaller
(useful for hash_skiplist_rep) and prepares skiplist for concurrent
adds. This diff also modifies the branching factor math to avoid an
unnecessary division.
This diff has the effect of changing the sequence of skip list node
height choices made by tests, so it has the potential to cause unit
test failures for tests that implicitly rely on the exact structure
of the skip list. Tests that try to exactly trigger a compaction are
likely suspects for this problem (these tests have always been brittle to
changes in the skiplist details). I've minimizes this risk by reseeding
the main thread's Random at the beginning of each test, increasing the
universal compaction size_ratio limit from 101% to 105% for some tests,
and verifying that the tests pass many times.
Test Plan: for i in `seq 0 9`; do make check; done
Reviewers: sdong, igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D50439
Summary:
This patch introduces OptionsSanityCheckLevel internally to enable
sanity check rocksdb options.
Utilities API will be added in the follow-up diffs.
Test Plan: Added more tests in options_test
Reviewers: igor, IslamAbdelRahman, sdong, anthony
Reviewed By: anthony
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D49515
Summary:
This patch introduces utilities/memory, which currently includes
GetApproximateMemoryUsageByType that reports different types of
rocksdb memory usage given a list of input DBs.
The API also take care of the case where Cache could be shared
across multiple column families / multiple db instances.
Currently, it reports memory usage of memtable, table-readers
and cache.
Test Plan: utilities/memory/memory_test.cc
Reviewers: igor, anthony, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D49257
Summary: This patch splits the posix storage backend into Env and
the actual *File implementations. The motivation is to allow other Envs
to use posix as a library. This enables a storage backend different from
posix to split its secondary storage between a normal file system
partition managed by posix, and it own media.
Test Plan: No new functionality is added to posix Env or the library,
thus the current tests should suffice.
Summary: In MyRocks, it is sometimes important to get propeties only for the subset of the database. This diff implements the API in RocksDB.
Test Plan: ran the GetPropertiesOfTablesInRange
Reviewers: rven, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48651
Summary:
We are cleaning up dependencies.
This diff takes a first step at moving memtable files to their own
directory called memtable. In future diffs, we will move other memtable
files from db to memtable.
Test Plan: make check
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D48915
Summary: As part of cleaning up dependencies for tech debt week, we are moving ldb and sst_dump tools from util to tools, since they are tools.
Test Plan: make check
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48747
Summary: manual_compaction_test.cc incorrectly in util. Moved to db.
Test Plan: make check
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48687
Summary:
As part of tech debt week, we are cleaning up dependencies.
This diff moves db_test_util.[h,cc] from util to db directory.
Test Plan: make check
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D48543
Summary:
Refactor dump_tool and undump_tool so that it's possible to use them with customized options
for example setting a specific comparator similar to what Dragon is doing with the LdbTool
https://phabricator.fb.com/diffusion/FBCODE/browse/master/dragon/tools/Ldb.cpp
Test Plan:
compiles
used it to dump / undump a dragon shard
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba, adsharma
Differential Revision: https://reviews.facebook.net/D47853
This commit adds two new targets to the Makefile: rocksdb.cc and rocksdb.h
These files, when combined with the c.h header, are a self-contained RocksDB
source distribution called an amalgamation. (The name comes from SQLite's, which
is similar in concept.)
The main benefit of an amalgamation is that it's very easy to drop into a
new project. It also compiles faster compared to compiling individual source
files and potentially gives the compiler more opportunity to make optimizations
since it can see all functions at once.
rocksdb.cc and rocksdb.h are generated by a new script, amalgamate.py.
A detailed description of how amalgamate.py works is in a comment at the top of
the file.
There are also some small changes to existing files to enable the amalgamation:
* Use quotes for includes in unity build
* Fix an old header inclusion in util/xfunc.cc
* Move some includes outside ifdef in util/env_hdfs.cc
* Separate out tool sources in Makefile so they won't be included in unity.cc
* Unity build now produces a static library
Closes#733
Summary:
This patch defines the format of RocksDB options file, which
follows the INI file format, and implements functions for its
serialization and deserialization. An example RocksDB options
file can be found in examples/rocksdb_option_file_example.ini.
A typical RocksDB options file has three sections, which are
Version, DBOptions, and more than one CFOptions. The RocksDB
options file in general follows the basic INI file format
with the following extensions / modifications:
* Escaped characters
We escaped the following characters:
- \n -- line feed - new line
- \r -- carriage return
- \\ -- backslash \
- \: -- colon symbol :
- \# -- hash tag #
* Comments
We support # style comments. Comments can appear at the ending
part of a line.
* Statements
A statement is of the form option_name = value.
Each statement contains a '=', where extra white-spaces
are supported. However, we don't support multi-lined statement.
Furthermore, each line can only contain at most one statement.
* Section
Sections are of the form [SecitonTitle "SectionArgument"],
where section argument is optional.
* List
We use colon-separated string to represent a list.
For instance, n1:n2:n3:n4 is a list containing four values.
Below is an example of a RocksDB options file:
[Version]
rocksdb_version=4.0.0
options_file_version=1.0
[DBOptions]
max_open_files=12345
max_background_flushes=301
[CFOptions "default"]
[CFOptions "the second column family"]
[CFOptions "the third column family"]
Test Plan: Added many tests in options_test.cc
Reviewers: igor, IslamAbdelRahman, sdong, anthony
Reviewed By: anthony
Subscribers: maykov, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D46059
Summary:
Fix hex2String performance issues by removing sscanf dependency.
Also fixed some edge case handling (odd length, bad input).
Test Plan: Created a test file which called old and new implementation, and validated results are the same. I'll paste results in the phabricator diff.
Reviewers: igor, rven, anthony, IslamAbdelRahman, kradhakrishnan, yhchiang, sdong
Reviewed By: sdong
Subscribers: thatsafunnyname, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D46785
Summary:
This is an initial version of bulk load feature
This diff allow us to create sst files, and then bulk load them later, right now the restrictions for loading an sst file are
(1) Memtables are empty
(2) Added sst files have sequence number = 0, and existing values in database have sequence number = 0
(3) Added sst files values are not overlapping
Test Plan: unit testing
Reviewers: igor, ott, sdong
Reviewed By: sdong
Subscribers: leveldb, ott, dhruba
Differential Revision: https://reviews.facebook.net/D39081
Summary:
Builder and CompactionJob share a lot of fairly complex code. This patch
refactors this code into a separate class, the CompactionIterator. Because the
shared code is fairly complex, this patch hopefully improves maintainability.
While there are is a lot of potential for further improvements, the patch is
intentionally pretty close to the original structure because the change is
already complex enough.
Test Plan: make clean all check && ./db_stress
Reviewers: rven, anthony, yhchiang, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D46197
Summary:
Prototype of API to allow MyRocks to override default Mutex/CondVar used by transactions with their own implementations. They would simply need to pass their own implementations of Mutex/CondVar to the templated TransactionDB::Open().
Default implementation of TransactionDBMutex/TransactionDBCondVar provided (but the code is not currently changed to use this).
Let me know if this API makes sense or if it should be changed
Test Plan: n/a
Reviewers: yhchiang, rven, igor, sdong, spetrunia
Reviewed By: spetrunia
Subscribers: maykov, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D43761
Summary: Provide a way to specify a detailed static error message for a Status without incurring a memcpy. Let me know what people think of this approach.
Test Plan: added simple test
Reviewers: igor, yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D44259
Summary:
As I keep adding new features to transactions, I keep creating more duplicate code. This diff cleans this up by creating a base implementation class for Transaction and OptimisticTransaction to inherit from.
The code in TransactionBase.h/.cc is all just copied from elsewhere. The only entertaining part of this class worth looking at is the virtual TryLock method which allows OptimisticTransactions and Transactions to share the same common code for Put/Get/etc.
The rest of this diff is mostly red and easy on the eyes.
Test Plan: No functionality change. existing tests pass.
Reviewers: sdong, jkedgar, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D45135
Summary:
Initial implementation of Pessimistic Transactions. This diff contains the api changes discussed in D38913. This diff is pretty large, so let me know if people would prefer to meet up to discuss it.
MyRocks folks: please take a look at the API in include/rocksdb/utilities/transaction[_db].h and let me know if you have any issues.
Also, you'll notice a couple of TODOs in the implementation of RollbackToSavePoint(). After chatting with Siying, I'm going to send out a separate diff for an alternate implementation of this feature that implements the rollback inside of WriteBatch/WriteBatchWithIndex. We can then decide which route is preferable.
Next, I'm planning on doing some perf testing and then integrating this diff into MongoRocks for further testing.
Test Plan: Unit tests, db_bench parallel testing.
Reviewers: igor, rven, sdong, yhchiang, yoshinorim
Reviewed By: sdong
Subscribers: hermanlee4, maykov, spetrunia, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D40869
Summary: Implemented this simple wrapper for something else I was working on. Seemed like it makes sense to expose it instead of burying it in some random code.
Test Plan: added test
Reviewers: rven, kradhakrishnan, sdong, yhchiang
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D43293
Summary: The list of info log files of a db can be obtained using the new function.
Test Plan: New test in db_test.cc passed.
Reviewers: yhchiang, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: IslamAbdelRahman, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D41715
Summary:
Add two unit tests for SyncWAL(). One makes sure SyncWAL() doesn't block writes in the other thread. Another one makes sure SyncWAL() doesn't wait ongoing writes to finish before being executed.
Create a new test file db_wal_test and move two WAL related tests from db_test to here.
Test Plan: Run the new tests
Reviewers: IslamAbdelRahman, rven, kradhakrishnan, kolmike, tnovak, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D43605
Summary:
Introduce DeleteScheduler that allow enforcing a rate limit on file deletion
Instead of deleting files immediately, files are moved to trash directory and deleted in a background thread that apply sleep penalty between deletes if needed.
I have updated PurgeObsoleteFiles and PurgeObsoleteWALFiles to use the delete_scheduler instead of env_->DeleteFile
Test Plan:
added delete_scheduler_test
existing unit tests
Reviewers: kradhakrishnan, anthony, rven, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D43221
Summary:
Merge pull request #665 by adamretter
Exposes BackupEngine from C++ to the Java API. Previously only BackupableDB was available
Test Plan: BackupEngineTest.java
Reviewers: fyrz, igor, ankgup87, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D42873
Summary:
This diff adds CompactOnDeletionCollector in utilities/table_properties_collectors,
which applies a sliding window to a sst file and mark this file as need-compaction
when it observe enough deletion entries within the consecutive keys covered by
the sliding window.
Test Plan: compact_on_deletion_collector_test
Reviewers: igor, anthony, IslamAbdelRahman, kradhakrishnan, yoshinorim, sdong
Reviewed By: sdong
Subscribers: maykov, dhruba
Differential Revision: https://reviews.facebook.net/D41175
Summary: Move general compaction tests from db_test.cc to db_compaction_test.cc
Test Plan:
db_test
db_compaction_test
Reviewers: igor, sdong, IslamAbdelRahman, anthony
Reviewed By: anthony
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42651
Summary: We want to keep Env a think layer for better portability. Less platform dependent codes should be moved out of Env. In this patch, I create a wrapper of file readers and writers, and put rate limiting, write buffering, as well as most perf context instrumentation and random kill out of Env. It will make it easier to maintain multiple Env in the future.
Test Plan: Run all existing unit tests.
Reviewers: anthony, kradhakrishnan, IslamAbdelRahman, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D42321
Summary: Moved convenience.h out of utilities to remove a dependency on utilities in db.
Test Plan: unit tests. Also compiled a link to the old location to verify the _Pragma works.
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42201
Summary: Move UniversalCompaction related db-tests to db_universal_compaction_test.cc
Test Plan:
db_test
db_universal_compaction_test
Reviewers: igor, sdong, IslamAbdelRahman, anthony
Reviewed By: anthony
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42225
Summary: Make TransactionLogIterator related tests from db_test.cc to db_log_iter_test.cc
Test Plan:
db_test
db_log_iter_test
Reviewers: sdong, IslamAbdelRahman, igor, anthony
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42045
Summary: Seems like the cleanest way to resolve this is to move CompactedDBImpl into db/. CompactedDBImpl should probably live in the same place as DBImplReadonly since Opening the latter could end up instantiating the former. Both DBImplReadonly and CompactedDBImpl inherit from DBImpl access protected members of DBImpl( and the latter access friendly private methods).
Test Plan: unit tests
Reviewers: sdong, yhchiang, kradhakrishnan, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42027
Summary:
Move reusable part of db_test.cc to util/db_test_util.h.
This makes it more possible to partition db_test.cc into
multiple smaller test files.
Also, fixed many old lint errors in db_test.
Test Plan: db_test
Reviewers: igor, anthony, IslamAbdelRahman, sdong, kradhakrishnan
Reviewed By: sdong, kradhakrishnan
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D41973
Summary:
When there are multiple column families, the flush in
GetLiveFiles is not atomic, so that there are entries in the wal files
which are needed to get a consisten RocksDB. We now add the log files to
the checkpoint.
Test Plan:
CheckpointCF - This test forces more data to be written to
the other column families after the flush of the first column family but
before the second.
Reviewers: igor, yhchiang, IslamAbdelRahman, anthony, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D40323
Summary:
Allow EventListener::OnCompactionCompleted to return CompactionJobStats,
which contains useful information about a compaction.
Example CompactionJobStats returned by OnCompactionCompleted():
smallest_output_key_prefix 05000000
largest_output_key_prefix 06990000
elapsed_time 42419
num_input_records 300
num_input_files 3
num_input_files_at_output_level 2
num_output_records 200
num_output_files 1
actual_bytes_input 167200
actual_bytes_output 110688
total_input_raw_key_bytes 5400
total_input_raw_value_bytes 300000
num_records_replaced 100
is_manual_compaction 1
Test Plan: Developed a mega test in db_test which covers 20 variables in CompactionJobStats.
Reviewers: rven, igor, anthony, sdong
Reviewed By: sdong
Subscribers: tnovak, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D38463
Summary:
We occasionally get write stalls (>1s Write() calls) on HDD under read load. The following timers explain almost all of the stalls:
- perf_context.db_mutex_lock_nanos
- perf_context.db_condition_wait_nanos
- iostats_context.open_time
- iostats_context.allocate_time
- iostats_context.write_time
- iostats_context.range_sync_time
- iostats_context.logger_time
In my experiments each of these occasionally takes >1s on write path under some workload. There are rare cases when Write() takes long but none of these takes long.
Test Plan: Added code to our application to write the listed timings to log for slow writes. They usually add up to almost exactly the time Write() call took.
Reviewers: rven, yhchiang, sdong
Reviewed By: sdong
Subscribers: march, dhruba, tnovak
Differential Revision: https://reviews.facebook.net/D39177
Summary: Optimistic transactions supporting begin/commit/rollback semantics. Currently relies on checking the memtable to determine if there are any collisions at commit time. Not yet implemented would be a way of enuring the memtable has some minimum amount of history so that we won't fail to commit when the memtable is empty. You should probably start with transaction.h to get an overview of what is currently supported.
Test Plan: Added a new test, but still need to look into stress testing.
Reviewers: yhchiang, igor, rven, sdong
Reviewed By: sdong
Subscribers: adamretter, MarkCallaghan, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D33435
Summary:
Rename EventLoggerHelpers EventHelpers, as it's going to include
all event-related helper functions instead of EventLogger only stuffs.
Test Plan: make
Reviewers: sdong, rven, anthony
Reviewed By: anthony
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D39093
Summary:
Added a couple functions to WriteBatchWithIndex to make it easier to query the value of a key including reading pending writes from a batch. (This is needed for transactions).
I created write_batch_with_index_internal.h to use to store an internal-only helper function since there wasn't a good place in the existing class hierarchy to store this function (and it didn't seem right to stick this function inside WriteBatchInternal::Rep).
Since I needed to access the WriteBatchEntryComparator, I moved some helper classes from write_batch_with_index.cc into write_batch_with_index_internal.h/.cc. WriteBatchIndexEntry, ReadableWriteBatch, and WriteBatchEntryComparator are all unchanged (just moved to a different file(s)).
Test Plan: Added new unit tests.
Reviewers: rven, yhchiang, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D38037
Summary:
Some Mongo+Rocks datasets in Parse's environment are not doing compactions very frequently. During the quiet period (with no IO), we'd like to schedule compactions so that our reads become faster. Also, aggressively compacting during quiet periods helps when write bursts happen. In addition, we also want to compact files that are containing deleted key ranges (like old oplog keys).
All of this is currently not possible with CompactRange() because it's single-threaded and blocks all other compactions from happening. Running CompactRange() risks an issue of blocking writes because we generate too much Level 0 files before the compaction is over. Stopping writes is very dangerous because they hold transaction locks. We tried running manual compaction once on Mongo+Rocks and everything fell apart.
MarkForCompaction() solves all of those problems. This is very light-weight manual compaction. It is lower priority than automatic compactions, which means it shouldn't interfere with background process keeping the LSM tree clean. However, if no automatic compactions need to be run (or we have extra background threads available), we will start compacting files that are marked for compaction.
Test Plan: added a new unit test
Reviewers: yhchiang, rven, MarkCallaghan, sdong
Reviewed By: sdong
Subscribers: yoshinorim, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D37083
Summary: Make target for running all xfunc tests
Test Plan: make xfunc
Reviewers: igor, sdong, meyering
Reviewed By: meyering
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36873
Summary:
* src.mk (JNI_NATIVE_SOURCES): New variable, so we don't have to use
a glob in Makefile
* Makefile (JNI_NATIVE_SOURCES): Remove glob-using definition, now
that the explicit list of sources is in src.mk.
Test Plan:
Run this:
JAVA_HOME=/usr/local/jdk-7u67-64 PATH=$JAVA_HOME/bin:$PATH \
make rocksdbjava
Reviewers: yhchiang
Reviewed By: yhchiang
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36633
Summary:
Just couple of small changes:
1. removed signal_test, since it doesn't seem useful and we don't even run it as part of `make check`
2. moved perf_context_test to TESTS instead of PROGRAMS
3. `make release` probably shouldn't compile benchmarks. We currently rely on `make release` building db_bench (via Jenkins), so I left db_bench there.
This is just a minor cleanup. We need to rethink our targets since they are a bit messy right now. We can do this during our tech debt week.
Test Plan: make release
Reviewers: anthony, rven, yhchiang, sdong, meyering
Reviewed By: meyering
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36171
Summary: Most of the approach is copied from WebSQL's MySQL branch. It's nice that we can do this without touching core RocksDB code.
Test Plan: Compiles and runs. Didn't test flashback code, as I don't have flashback device and most if it is c/p
Reviewers: MarkCallaghan, sdong
Reviewed By: sdong
Subscribers: rven, lgalanis, kradhakrishnan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D35391
Summary: WriteBatch and WriteBatchWithIndex now both inherit from a common abstract base class. This makes it easier to write code that is agnostic toward the implementation of the particular write batch. In particular, I plan on utilizing this abstraction to allow transactions to support using either implementation of a write batch.
Test Plan: modified existing WriteBatchWithIndex tests to test new functions. Running all tests.
Reviewers: igor, rven, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D34017
Summary:
Adds gtest fused source code into `third-party` directory. No manual changes.
gtest latest released 1.7 has clang dev compilation errors. Trunk version requires only one disabled warning (-Wno-missing-field-initializers)
Fused code is made as described here https://fburl.com/90806322
Details about why we need gtest source code instead of precompiled library https://fburl.com/90805763
Source used from http://googletest.googlecode.com/svn/trunk
Test Plan:
Build and notice no errors. Also check in logs that gtest-all.o being compiled gtest-all.o.
```lang=bash
% USE_CLANG=1 make all
```
Reviewers: lgalanis, yufei.zhu, rven, sdong, igor, meyering
Reviewed By: meyering
Subscribers: meyering, yhchiang, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D33345
Summary:
Here's my proposal for making our LOGs easier to read by machines.
The idea is to dump all events as JSON objects. JSON is easy to read by humans, but more importantly, it's easy to read by machines. That way, we can parse this, load into SQLite/mongo and then query or visualize.
I started with table_create and table_delete events, but if everybody agrees, I'll continue by adding more events (flush/compaction/etc etc)
Test Plan:
Ran db_bench. Observed:
2015/01/15-14:13:25.788019 1105ef000 EVENT_LOG_v1 {"time_micros": 1421360005788015, "event": "table_file_creation", "file_number": 12, "file_size": 1909699}
2015/01/15-14:13:25.956500 110740000 EVENT_LOG_v1 {"time_micros": 1421360005956498, "event": "table_file_deletion", "file_number": 12}
Reviewers: yhchiang, rven, dhruba, MarkCallaghan, lgalanis, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D31647
Summary:
The build process now requires new source files to be added to
src.mk. Adding convenience.cc to src.mk
Test Plan: Build rocksdb
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D34815
Summary:
* src.mk (LIB_SOURCES): Add this file:
utilities/document/json_document_builder.cc
to avoid link errors.
Blame Rev: D33849
Test Plan: run "make"
Reviewers: ljin, igor.sugak, rven, sdong, igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D34593
Summary:
Any time one would modify a dependent of any *test*.cc file,
"make" would fail to rebuild the affected test binaries,
e.g., db_test. That was due to the fact that we deliberately
excluded those test-related files from the definition of SOURCES
and only $(SOURCES) was used to create the automatically-generated
.d dependency files. The fix is to generate a .d file for every
source file.
* src.mk: New file. Defines LIB_SOURCES, MOCK_SOURCES
and TEST_BENCH_SOURCES.
* Makefile: Include src.mk.
Reflect s/SOURCES/LIB_SOURCES/ renaming.
* build_tools/build_detect_platform: Remove the code
that was used to generate SOURCES= and MOCK_SOURCES=
definitions in make_config.mk. Those lists of files
are now hard-coded in src.mk. Hard-coding this list of
sources is desirable, because without that, one risks
including stray .cc files in a build. Not reproducible.
Test Plan:
Touch a file used by db_test's dependent .o files and ensure that
they are all recompiled. Before, none would be:
$ touch db/db_impl.h && make db_test
CC db/db_test.o
CC db/column_family.o
CC db/db_filesnapshot.o
CC db/db_impl.o
CC db/db_impl_debug.o
CC db/db_impl_readonly.o
CC db/forward_iterator.o
CC db/internal_stats.o
CC db/managed_iterator.o
CC db/repair.o
CC db/write_batch.o
CC utilities/compacted_db/compacted_db_impl.o
CC utilities/ttl/db_ttl_impl.o
CC util/ldb_cmd.o
CC util/ldb_tool.o
CC util/sst_dump_tool.o
CC util/xfunc.o
CCLD db_test
Reviewers: ljin, igor.sugak, igor, rven, sdong
Reviewed By: sdong
Subscribers: yhchiang, adamretter, fyrz, dhruba
Differential Revision: https://reviews.facebook.net/D33849