Summary: We keep checksum functions in util/, there is no reason for compression to be in port/
Test Plan: compiles
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D31281
Summary:
Create a benchmark for testing memtablereps. This diff is a bit rough, but it should do the trick until other bootcampers can clean it up.
Addressing comments
Removed the mutexes
Changed ReadWriteBenchmark to fix number of reads and count the number of writes we can perform in that time.
Test Plan:
Run it.
Below runs pass
./memtablerep_bench --benchmarks fillrandom,readrandom --memtablerep skiplist
./memtablerep_bench --benchmarks fillseq,readseq --memtablerep skiplist
./memtablerep_bench --benchmarks readwrite,seqreadwrite --memtablerep skiplist --num_operations 200 --num_threads 5
./memtablerep_bench --benchmarks fillrandom,readrandom --memtablerep hashskiplist
./memtablerep_bench --benchmarks fillseq,readseq --memtablerep hashskiplist
--num_scans 2
./memtablerep_bench --benchmarks fillseq,readseq --memtablerep vector
Reviewers: jpaton, ikabiljo, sdong
Reviewed By: sdong
Subscribers: dhruba, ameyag
Differential Revision: https://reviews.facebook.net/D22683
Summary: Add comments in db.h to help users discover their options.
Test Plan: Compile
Reviewers: rven, yhchiang, igor
Reviewed By: igor
Subscribers: MarkCallaghan, yoshinorim, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D31077
Summary: Add an extra assert to make sure current version is included in VersionSet::AddLiveFiles().
Test Plan: make all check
Reviewers: yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, hermanlee4, leveldb
Differential Revision: https://reviews.facebook.net/D30819
Summary: During recovery, VersionBuilder::Apply() was called multiple times. If the DB is open for long enough, most of files added earlier will be deleted by later deletes. In current solution, sorting added file happens first and then deletes are applied. In this patch, deletes are applied when possible inside Apply(), which can significantly reduce the sorting time in some cases.
Test Plan:
Add unit tests in version_builder
valgrind_check
Open a manifest of 50MB, with 9K live files. The manifest read time reduced from 1.6 seconds to 0.7 seconds.
Reviewers: rven, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30765
Summary:
This patch changes concurrency guarantees around ColumnFamilySet::column_families_ and ColumnFamilySet::column_families_data_.
Before:
* When mutating: lock DB mutex and spin lock
* When reading: lock DB mutex OR spin lock
After:
* When mutating: lock DB mutex and be in write thread
* When reading: lock DB mutex or be in write thread
That way, we eliminate the spin lock that protects these hash maps and simplify concurrency. That means we don't need to lock the spin lock during writing, since writing is mutually exclusive with column family create/drop (the only operations that mutate those hash maps).
With these new restrictions, I also needed to move column family create to the write thread (column family drop was already in the write thread).
Even though we don't need to lock the spin lock during write, impact on performance should be minimal -- the spin lock is almost never busy, so locking it is almost free.
This addresses task t5116919.
Test Plan:
make check
Stress test with lots and lots of column family drop and create:
time ./db_stress --threads=30 --ops_per_thread=5000000 --max_key=5000 --column_families=200 --clear_column_family_one_in=100000 --verify_before_write=0 --reopen=15 --max_background_compactions=10 --max_background_flushes=10 --db=/fast-rocksdb-tmp/db_stress/
Reviewers: yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30651
Summary: When trivial move commit is done, we log the summary of the input version instead of current. This is inconsistent with other log messages and confusing.
Test Plan: compiles
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30939
Summary:
A command line like this to run all the tests:
source benchmark.config.sh && nohup ./benchmark.sh 'bulkload,fillseq,overwrite,filluniquerandom,readrandom,readwhilewriting'
where
benchmark.config.sh is:
export DB_DIR=/data/mysql/rocksdata
export WAL_DIR=/txlogs/rockswal
export OUTPUT_DIR=/root/rocks_benchmarking/output
Will fail for the tests that need a new DB .
Also 1) set disable_data_sync=0 and 2) add debug mode to run through all the tests more quickly
Test Plan: run ./benchmark.sh 'debug,bulkload,fillseq,overwrite,filluniquerandom,readrandom,readwhilewriting' and verify that there are no complaints about WAL dir not being empty.
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D30909
Summary:
Since https://reviews.facebook.net/D16119, we ignore partial tailing writes. Because of that, we no longer need skip_log_error_on_recovery.
The documentation says "Skip log corruption error on recovery (If client is ok with losing most recent changes)", while the option actually ignores any corruption of the WAL (not only just the most recent changes). This is very dangerous and can lead to DB inconsistencies. This was originally set up to ignore partial tailing writes, which we now do automatically (after D16119). I have digged up old task t2416297 which confirms my findings.
Test Plan: There was actually no tests that verified correct behavior of skip_log_error_on_recovery.
Reviewers: yhchiang, rven, dhruba, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30603
Summary:
This is a serious bug. If paranod_check == true and WAL is corrupted, we don't fail DB::Open(). I tried going into history and it seems we've been doing this for a long long time.
I found this when investigating t5852041.
Test Plan: Added unit test to verify correct behavior.
Reviewers: yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30597
Summary: CLANG was broken for a recent change in db_ench. Fix it.
Test Plan: Build db_bench using CLANG.
Reviewers: rven, igor, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30801
Summary:
Add structures for exposing events and operations. Event describes
high-level action about a thread such as doing compaciton or
doing flush, while an operation describes lower-level action
of a thread such as reading / writing a SST table, waiting for
mutex. Events and operations are designed to be independent.
One thread would typically involve in one event and one operation.
Code instrument will be in a separate diff.
Test Plan:
Add unit-tests in thread_list_test
make dbg -j32
./thread_list_test
export ROCKSDB_TESTS=ThreadList
./db_test
Reviewers: ljin, igor, sdong
Reviewed By: sdong
Subscribers: rven, jonahcohen, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29781
Summary: Having --num_hot_column_families default on fails some existing regression tests. By default turn it off
Test Plan: Run db_bench to make sure it is default off.
Reviewers: yhchiang, rven, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D30705
Summary:
Add option --num_hot_column_families in db_bench. If it is set, write options will first write to that number of column families, and then move on to next set of hot column families. The working set of column families can be smaller than total number of CFs.
It is to test how RocksDB can handle cold column families
Test Plan: Run db_bench with --num_hot_column_families set and not set.
Reviewers: yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30663
Dike out the body of VerifyCompactionResult. With assert() compiled out, the
loop index variable in the inner loop was unused, breaking the build when
-Werror is enabled.
Summary:
GetThreadList() feature depends on the thread creation and destruction, which is currently handled under Env.
This patch moves GetThreadList() feature under Env to better manage the dependency of GetThreadList() feature
on thread creation and destruction.
Renamed ThreadStatusImpl to ThreadStatusUpdater. Add ThreadStatusUtil, which is a static class contains
utility functions for ThreadStatusUpdater.
Test Plan: run db_test, thread_list_test and db_bench and verify the life cycle of Env and ThreadStatusUpdater is properly managed.
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: ljin, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30057
Summary: As title. We shouldn't need to execute flush from compaction if there are dedicated threads doing flushes.
Test Plan: make check
Reviewers: rven, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30579
Summary:
There are two versions of FindObsoleteFiles():
* full scan, which is executed every 6 hours (and it's terribly slow)
* no full scan, which is executed every time a background process finishes and iterator is deleted
This diff is optimizing the second case (no full scan). Here's what we do before the diff:
* Get the list of obsolete files (files with ref==0). Some files in obsolete_files set might actually be live.
* Get the list of live files to avoid deleting files that are live.
* Delete files that are in obsolete_files and not in live_files.
After this diff:
* The only files with ref==0 that are still live are files that have been part of move compaction. Don't include moved files in obsolete_files.
* Get the list of obsolete files (which exclude moved files).
* No need to get the list of live files, since all files in obsolete_files need to be deleted.
I'll post the benchmark results, but you can get the feel of it here: https://reviews.facebook.net/D30123
This depends on D30123.
P.S. We should do full scan only in failure scenarios, not every 6 hours. I'll do this in a follow-up diff.
Test Plan:
One new unit test. Made sure that unit test fails if we don't have a `if (!f->moved)` safeguard in ~Version.
make check
Big number of compactions and flushes:
./db_stress --threads=30 --ops_per_thread=20000000 --max_key=10000 --column_families=20 --clear_column_family_one_in=10000000 --verify_before_write=0 --reopen=15 --max_background_compactions=10 --max_background_flushes=10 --db=/fast-rocksdb-tmp/db_stress --prefixpercent=0 --iterpercent=0 --writepercent=75 --db_write_buffer_size=2000000
Reviewers: yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30249
Summary:
This one wasn't easy to find :)
What happens is we go through all cfds on flush_queue_ and find no cfds to flush, *but* the cfd is set to the last CF we looped through and following code assumes we want it flushed.
BTW @sdong do you think we should also make BackgroundFlush() only check a single cfd for flushing instead of doing this `while (!flush_queue_.empty())`?
Test Plan: regression test no longer fails
Reviewers: sdong, rven, yhchiang
Reviewed By: yhchiang
Subscribers: sdong, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30591
Summary:
When scaling to higher number of column families, the worst bottleneck was MaybeScheduleFlushOrCompaction(), which did a for loop over all column families while holding a mutex. This patch addresses the issue.
The approach is similar to our earlier efforts: instead of a pull-model, where we do something for every column family, we can do a push-based model -- when we detect that column family is ready to be flushed/compacted, we add it to the flush_queue_/compaction_queue_. That way we don't need to loop over every column family in MaybeScheduleFlushOrCompaction.
Here are the performance results:
Command:
./db_bench --write_buffer_size=268435456 --db_write_buffer_size=268435456 --db=/fast-rocksdb-tmp/rocks_lots_of_cf --use_existing_db=0 --open_files=55000 --statistics=1 --histogram=1 --disable_data_sync=1 --max_write_buffer_number=2 --sync=0 --benchmarks=fillrandom --threads=16 --num_column_families=5000 --disable_wal=1 --max_background_flushes=16 --max_background_compactions=16 --level0_file_num_compaction_trigger=2 --level0_slowdown_writes_trigger=2 --level0_stop_writes_trigger=3 --hard_rate_limit=1 --num=33333333 --writes=33333333
Before the patch:
fillrandom : 26.950 micros/op 37105 ops/sec; 4.1 MB/s
After the patch:
fillrandom : 17.404 micros/op 57456 ops/sec; 6.4 MB/s
Next bottleneck is VersionSet::AddLiveFiles, which is painfully slow when we have a lot of files. This is coming in the next patch, but when I removed that code, here's what I got:
fillrandom : 7.590 micros/op 131758 ops/sec; 14.6 MB/s
Test Plan:
make check
two stress tests:
Big number of compactions and flushes:
./db_stress --threads=30 --ops_per_thread=20000000 --max_key=10000 --column_families=20 --clear_column_family_one_in=10000000 --verify_before_write=0 --reopen=15 --max_background_compactions=10 --max_background_flushes=10 --db=/fast-rocksdb-tmp/db_stress --prefixpercent=0 --iterpercent=0 --writepercent=75 --db_write_buffer_size=2000000
max_background_flushes=0, to verify that this case also works correctly
./db_stress --threads=30 --ops_per_thread=2000000 --max_key=10000 --column_families=20 --clear_column_family_one_in=10000000 --verify_before_write=0 --reopen=3 --max_background_compactions=3 --max_background_flushes=0 --db=/fast-rocksdb-tmp/db_stress --prefixpercent=0 --iterpercent=0 --writepercent=75 --db_write_buffer_size=2000000
Reviewers: ljin, rven, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30123
Summary: Avoid unnecessary unlock and lock mutex when notifying events.
Test Plan: ./listener_test
Reviewers: igor
Reviewed By: igor
Subscribers: sdong, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30267
Summary:
We now release the mutex before copying the files in the case
of the trivial move. This path does not use the compaction job.
Test Plan: DBTest.LevelCompactionThirdPath
Reviewers: yhchiang, igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30381
Summary:
Allow Level-style compaction to place files in different paths
This diff provides the code for task 4854591. We now support level-compaction
to place files in different paths by specifying them in db_paths along with
the minimum level for files to store in that path.
Test Plan: ManualLevelCompactionOutputPathId in db_test.cc
Reviewers: yhchiang, MarkCallaghan, dhruba, yoshinorim, sdong
Reviewed By: sdong
Subscribers: yoshinorim, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29799
Summary:
ASAN build fails once for this error:
14:04:52 ==== Test DBTest.CompactFilesOnLevelCompaction
14:04:52 db_test: db/version_set.cc:1062: void rocksdb::VersionStorageInfo::AddFile(int, rocksdb::FileMetaData*): Assertion `level <= 0 || level_files->empty() || internal_comparator_->Compare( (*level_files)[level_files->size() - 1]->largest, f->smallest) < 0' failed.
Not abling figure out reason. We use std:vector for sorting for save and add one more assert to help figure out whether it is the sorting's problem.
Test Plan: make all check
Reviewers: yhchiang, rven, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D30117
Summary: Now DB::GetSnapshot() doesn't scale to more column families, as it needs to go through all the column families to find whether snapshot is supported. This patch optimizes it.
Test Plan:
Add unit tests to cover negative cases.
make all check
Reviewers: yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D30093
Summary: Set operations in VerisonBuilder is shown as a performance bottleneck of restarting DB when there are lots of files. Make both of added_files and deleted_files use unordered set or map. Only when adding the files, sort the added files.
Test Plan: make all check
Reviewers: yhchiang, rven, igor
Reviewed By: igor
Subscribers: hermanlee4, leveldb, dhruba, ljin
Differential Revision: https://reviews.facebook.net/D30051
Summary: This is a regression bug introduced by https://reviews.facebook.net/D24729 . max_total_wal_size would be off the target it should be more and more in the case that the a user holds the current super version after flush or compaction. This patch fixes it
Test Plan: make all check
Reviewers: yhchiang, rven, igor
Reviewed By: igor
Subscribers: ljin, yoshinorim, MarkCallaghan, hermanlee4, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29961
Summary: When wal_dir is used, DestroyDB is not passed the wal_dir option and so we get a Corruption exception.
Test Plan:
Verified manually that the following command line works now:
./db_bench --db=/mnt/db/rocksdb ... --disable_wal=0 --wal_dir=/data/users/rocksdb/WAL... --benchmarks=filluniquerandom --use_existing_db=0...
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29859
Summary:
Add a counter in SnapshotList to show number of snapshots. Also a unix timestamp in every snapshot.
Add two DB Properties to return number of snapshots and timestamp of the oldest one.
Test Plan: Add unit test checking
Reviewers: yhchiang, rven, igor
Reviewed By: igor
Subscribers: leveldb, dhruba, MarkCallaghan
Differential Revision: https://reviews.facebook.net/D29919
Summary:
Remove the use of exception in WriteBatch::Handler. Now the default
implementations of Put, Merge, and Delete in WriteBatch::Handler are no-op.
Test Plan:
Add three test cases in write_batch_test
./write_batch_test
Reviewers: sdong, igor
Reviewed By: sdong, igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29835
Summary: Replace exception by setting valid_ = false in DBIter::MergeValuesNewToOld().
Test Plan:
Not sure if I am right at this, but it seems we currently don't have a good
way to test that code path as it requires dynamically set merge_operator = nullptr
at the time while Merge() is calling.
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29811
Summary:
Introduces a new class for managing write buffer memory across column
families. We supplement ColumnFamilyOptions::write_buffer_size with
ColumnFamilyOptions::write_buffer, a shared pointer to a WriteBuffer
instance that enforces memory limits before flushing out to disk.
Test Plan: Added SharedWriteBuffer unit test to db_test.cc
Reviewers: sdong, rven, ljin, igor
Reviewed By: igor
Subscribers: tnovak, yhchiang, dhruba, xjin, MarkCallaghan, yoshinorim
Differential Revision: https://reviews.facebook.net/D22581
Summary:
Two fixes:
1. if cpplint is not present on the system, don't return a confusing error in the linter
2. Add include_alpha, which means our includes should be sorted lexicographically
Test Plan: Tried unsorting our includes, lint complained
Reviewers: rven, ljin, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28845
Summary: Block Universal and FIFO compactions in ROCKSDB_LITE
Test Plan:
make shared_lib -j32
make OPT=-DROCKSDB_LITE shared_lib
Reviewers: ljin, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29589
Summary:
db_imp_readonly.o is one of the big obj file. If it's not a necessary
feature, we should probably block it in ROCKSDB_LITE.
1322704 Nov 24 16:55 db/db_impl_readonly.o
Test Plan:
make shared_lib -j32
make ROCKSDB_LITE shared_lib -j32
Reviewers: ljin, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29583
Summary: Block internal_stats in ROCKSDB_LITE.
Test Plan: make OPT=-DROCKSDB_LITE shared_lib
Reviewers: ljin, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29541
Summary:
In some environment such as android, the c++ library does not have
std::to_string. This path adds rocksdb::ToString(), which wraps std::to_string
when std::to_string is not available, and implements std::to_string
in the other case.
Test Plan:
make dbg -j32
./db_test
make clean
make dbg OPT=-DOS_ANDROID -j32
./db_test
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29181
Summary:
This compaction trigger does not seem to test any thing specific to
cuckoo table. Remove it.
Test Plan: make all check
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29523
Summary:
Reported by bootcamper
This causes ldb tool to fail the assertion in ~ColumnFamilyData()
Test Plan:
./ldb --db=/tmp/test_db1 --create_if_missing put a1 b1
./ldb manifest_dump --path=/tmp/test_db1/MANIFEST-000001
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29517
Summary: Free checkpoint after its directory is removed.
Test Plan: Run valgrind with GetSnapshotLink.
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29493
Summary:
An entry of ConstantColumnFamilyInfo is created when:
1. DB::Open
2. CreateColumnFamily.
However, there are cases that DB::Open could also call CreateColumnFamily
when create_missing_column_families=true. As a result, it will create
duplicate ConstantColumnFamilyInfo and one of them would be leaked.
Test Plan: ./deletefile_test
Reviewers: igor, sdong, ljin
Reviewed By: ljin
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29307
Summary: "build all" breaks in Clang mode with db_bench. Fix it.
Test Plan: USE_CLANG=1 make all
Reviewers: ljin, rven, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D29379
Summary: Improve listener_test by ensuring flushes are completed before assert.
Test Plan: listener_test
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29319
Summary: stringSplit is not how we name our functions. Also, we had two StringSplit's in the codebase
Test Plan: make check
Reviewers: yhchiang, dhruba
Reviewed By: dhruba
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29361
Summary:
Add enable_thread_tracking to DBOptions to allow
tracking thread status related to the DB. Default is off.
Test Plan:
export ROCKSDB_TESTS=ThreadList
./db_test
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29289
Summary:
Add GetThreadList API, which allows developer to track the
status of each process. Currently, calling GetThreadList will
only get the list of background threads in RocksDB with their
thread-id and thread-type (priority) set. Will add more support
on this in the later diffs.
ThreadStatus currently has the following properties:
// An unique ID for the thread.
const uint64_t thread_id;
// The type of the thread, it could be ROCKSDB_HIGH_PRIORITY,
// ROCKSDB_LOW_PRIORITY, and USER_THREAD
const ThreadType thread_type;
// The name of the DB instance where the thread is currently
// involved with. It would be set to empty string if the thread
// does not involve in any DB operation.
const std::string db_name;
// The name of the column family where the thread is currently
// It would be set to empty string if the thread does not involve
// in any column family.
const std::string cf_name;
// The event that the current thread is involved.
// It would be set to empty string if the information about event
// is not currently available.
Test Plan:
./thread_list_test
export ROCKSDB_TESTS=GetThreadList
./db_test
Reviewers: rven, igor, sdong, ljin
Reviewed By: ljin
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D25047
Summary:
The very last reference happens in DBImpl::GetOptions()
I built with both DBImpl::GetOptions() and ColumnFamilyData::options() commented out
Test Plan: make all check
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D29073
Summary: Fixed a bug which could hide non-ok status in CompactionJob::Run()
Test Plan: make
Reviewers: sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28995
Summary: This way we can gurantee that old MemTables get destructed before DBImpl gets destructed, which might be useful if we want to make them depend on state from DBImpl.
Test Plan: make check with asserts in JobContext's destructor
Reviewers: ljin, sdong, yhchiang, rven, jonahcohen
Reviewed By: jonahcohen
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28959
Summary: Store links to live files in directory on same disk
Test Plan:
Take snapshot and open it. Added a test GetSnapshotLink in
db_test.
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28713
Summary:
This is just a simple test that passes two files though a compaction. It shows the framework so that people can continue building new compaction *unit* tests.
In the future we might want to move some Compaction* tests from DBTest here. For example, CompactBetweenSnapshot seems a good candidate.
Hopefully this test can be simpler when we mock out VersionSet.
Test Plan: this is a test
Reviewers: ljin, rven, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28449
Summary:
Make db_stress built for ROCKSDB_LITE.
The test doesn't pass tough. It seg fault quickly. But I took a look and it doesn't seem to be related to lite version. Likely to be a bug inside RocksDB.
Test Plan: make db_stress
Reviewers: yhchiang, rven, ljin, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D28797
Summary: Add a unit test in db_test to verify the behavior when both of merge operator and compaction filter apply to a key when merging.
Test Plan: Run the new test
Reviewers: ljin, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28455
Summary: As a short-term fix, let's go back to previous way of calculating NeedsCompaction(). SIGSEGV happens because NeedsCompaction() can happen before super_version (and thus MutableCFOptions) is initialized.
Test Plan: make check
Reviewers: ljin, sdong, rven, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28875
Summary:
Move NeedsCompaction() from VersionStorageInfo to CompactionPicker
to allow different compaction strategy to have their own way to
determine whether doing compaction is necessary.
When compaction style is set to kCompactionStyleNone, then
NeedsCompaction() will always return false.
Test Plan:
export ROCKSDB_TESTS=Compact
./db_test
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28719
Summary: So iOS size_t is 32-bit, so we need to static_cast<size_t> any uint64_t :(
Test Plan: TARGET_OS=IOS make static_lib
Reviewers: dhruba, ljin, yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28743
Summary: I found that db_stress sometimes segfault on my machine. Fix the bug.
Test Plan: make all check. Run db_stress
Reviewers: ljin, yhchiang, rven, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D28803
Summary:
Fixed a bug in GetEstimatedActiveKeys which does not normalized
the sampled information correctly.
Add a test in version_builder_test.
Test Plan: version_builder_test
Reviewers: ljin, igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28707
Summary:
We need to turn on -Wshorten-64-to-32 for mobile. See D1671432 (internal phabricator) for details.
This diff turns on the warning flag and fixes all the errors. There were also some interesting errors that I might call bugs, especially in plain table. Going forward, I think it makes sense to have this flag turned on and be very very careful when converting 64-bit to 32-bit variables.
Test Plan: compiles
Reviewers: ljin, rven, yhchiang, sdong
Reviewed By: yhchiang
Subscribers: bobbaldwin, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28689
Summary: I mistakenly changed the behavior to ++next_file_number_ instead of next_file_number_++, as it should have been: 344edbb044/db/version_set.h (L539)
Test Plan: none. not sure if this would break anything. It's just different behavior, so I'd rather not risk
Reviewers: ljin, rven, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28557
Summary:
In D19581 I made `ForwardIterator::status()` check all child iterators,
including immutable ones. It's, however, not necessary to do it every
time -- it'll suffice to check only when they're used and their status
could change.
This diff:
* introduces `immutable_status_` which is updated by `Seek()` and `Next()`
* removes special handling of `kIncomplete` status in those methods
Test Plan:
* `db_test`
* hacked ReadSequential in db_bench.cc to check `status()` in addition to
validity:
```
$ ./db_bench -use_existing_db -benchmarks readseq -disable_auto_compactions \
-use_tailing_iterator # without this patch
Keys: 16 bytes each
Values: 100 bytes each (50 bytes after compression)
Entries: 1000000
[...]
DB path: [/dev/shm/rocksdbtest/dbbench]
readseq : 0.562 micros/op 1778103 ops/sec; 98.4 MB/s
$ ./db_bench -use_existing_db -benchmarks readseq -disable_auto_compactions \
-use_tailing_iterator # with the patch
readseq : 0.433 micros/op 2311363 ops/sec; 127.8 MB/s
```
Reviewers: igor, sdong, ljin
Reviewed By: ljin
Subscribers: dhruba, leveldb, march, lovro
Differential Revision: https://reviews.facebook.net/D24063
Summary: Based on @sdong's feedback in the diff, we shouldn't keep db_mutex in CompactionJob's state. This diff removes db_mutex from CompactionJob state, by making next_file_number_ atomic. That way we only need to pass the lock to InstallCompactionResults() because of LogAndApply()
Test Plan: make check
Reviewers: ljin, yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: sdong, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28491
Summary: Previously I made `make check` work with -Wshadow, but there are some tools that are not compiled using `make check`.
Test Plan: make all
Reviewers: yhchiang, rven, ljin, sdong
Reviewed By: ljin, sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28497
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
Summary:
Here's a prototype of redesigning pending_outputs_. This way, we don't have to expose pending_outputs_ to other classes (CompactionJob, FlushJob, MemtableList). DBImpl takes care of it.
Still have to write some comments, but should be good enough to start the discussion.
Test Plan: make check, will also run stress test
Reviewers: ljin, sdong, rven, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28353
Summary:
Make PartialCompactionFailure Test more robust again by
blocking background compaction until we simulate the
file creation error.
Test Plan:
export ROCKSDB_TESTS=PartialCompactionFailure
./db_test
Reviewers: sdong, igor, ljin
Reviewed By: ljin
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28431
Summary:
TEST_WaitForFlush should wait until it sees error when parameter is set
to true so we don't need to loop and timeout
Test Plan: ROCKSDB_TESTS=DropWritesFlush ./db_test
Reviewers: sdong, igor
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28419
Summary: Make PartialCompactionFailure Test more robust.
Test Plan:
export ROCKSDB_TESTS=PartialCompactionFailure
./db_test
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28425
Summary: It turns out that -Wshadow has different rules for gcc than clang. Previous commit fixed clang. This commits fixes the rest of the warnings for gcc.
Test Plan: compiles
Reviewers: ljin, yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28131
Summary: In order to avoid random failure of DBTest.GroupCommitTest, artificially sleep 100 microseconds in each log writing.
Test Plan: Run the test in a machine where valgrind version of the test always fails multiple times and see it always succeed.
Reviewers: igor, yhchiang, rven, ljin
Reviewed By: ljin
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D28401
Summary: This patch makes it a contract that if an empty write batch is passed to DB::Write() and WriteOptions.sync = true, fsync is called to WAL.
Test Plan: A new unit test
Reviewers: ljin, rven, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba, MarkCallaghan, leveldb
Differential Revision: https://reviews.facebook.net/D28365
Summary:
1. fix possible overflow of the two stats by using uint64_t
2. use a similar source of data to calculate RecordDrop. Previous one is not correct.
Test Plan: See outputs of db_bench settings, and the results look reasonable
Reviewers: MarkCallaghan, ljin, igor
Reviewed By: igor
Subscribers: rven, leveldb, yhchiang, dhruba
Differential Revision: https://reviews.facebook.net/D28155
If a compaction filter implementation is simply filtering values, then
allocating the "changed values" bitmap is an extra memory allocation
that adds no value. Additionally, the compaction implementation has to
do marginally more work to calculate the offset into the bitmap
(vector<bool> specialization) for each record the filter did not mark
for deletion.
Explicitly handle the case where compact_->value_changed_buf_ is empty.
Summary: as title
Test Plan: ./db_test
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28269
Summary: as title
Test Plan: ran it
Reviewers: yhchiang, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28311
Summary: Replace some ASSERT_TRUE() to ASSERT_GT() and ASSERT_LT() so that in case the assert is triggered, the value is printed out.
Test Plan: Run the two tests
Reviewers: ljin, rven, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D28293
Summary:
Now DBTest.DynamicMemtableOptions sets background compaction to be 4, without actually increasing thread pool size (even before the feature of automatic increasing it). To make sure the behavior stays the same after the automatic thread pool increasing, set it back to 1.
Hopefully it can fix the occasional failure of the test.
Test Plan: Run the test
Reviewers: igor, ljin
Reviewed By: ljin
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D28281
Summary: Apply InfoLogLevel to the logs in db/compaction_job.cc
Test Plan: db_test
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: leveldb, MarkCallaghan, dhruba
Differential Revision: https://reviews.facebook.net/D28275
Summary: Apply InfoLogLevel to the logs in db/version_set.cc
Test Plan: make
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27879
Summary: Apply InfoLogLevel to the logs in db/wal_manager.cc
Test Plan: db_test
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28239
Summary: Apply InfoLogLevel to the logs in db/db_impl.cc
Test Plan:
db_test
db_bench
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: leveldb, MarkCallaghan, dhruba
Differential Revision: https://reviews.facebook.net/D28233
Summary: Enforce the accessier naming convention in functions in version_set.h
Test Plan: make all check
Reviewers: ljin, yhchiang, rven, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D28143
Summary:
With the patch, thread pool size will be automatically increased if DB's options ask for more parallelism of compactions or flushes.
Too many users have been confused by the API. Change it to make it harder for users to make mistakes
Test Plan: Add two unit tests to cover the function.
Reviewers: yhchiang, rven, igor, MarkCallaghan, ljin
Reviewed By: ljin
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27555
Summary: Move all the logic of VersionBuilder to a separate .cc file
Test Plan: make all check
Reviewers: ljin, yhchiang, rven, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D28083
Summary:
Long awaited CompactionJob class! Move most compaction-related things from DBImpl to CompactionJob, making CompactionJob easier to test and understand.
Currently this is just replicating exactly the same functionality with as little as change as possible. As future work, we should:
1. Add CompactionJob tests (I think I'll do that tomorrow)
2. Reduce CompactionJob's state that it inherits from DBImpl
3. Figure out how to do yielding to flush better. Currently I implemented a callback as we agreed yesterday, but I don't think it's a good long term solution.
This reduces db_impl.cc from 5000+ LOC to 3400!
Test Plan: make check, will add CompactionJob-specific tests, probably also move some tests from db_test to compaction_job_test
Reviewers: rven, yhchiang, sdong, ljin
Reviewed By: ljin
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27957
Summary:
TestMemEnv simulates all Env APIs using in-memory data structures.
We can use it to speed up db_test run, which is now reduced ~7mins when it is
enabled.
We can also add features to simulate power/disk failures in the next
step
TestMemEnv is derived from helper/mem_env
mem_env can not be used for rocksdb since some of its APIs do not give
the same results as env_posix. And its file read/write is not thread safe
Test Plan:
make all -j32
./db_test
./env_mem_test
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28035
Summary: as title
Test Plan: make release
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28053
Summary: as title
Test Plan: ./c_test
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28119
Summary: now we use %8d for RecordIn and %10d for RecordDrop, which is far too small for some use cases. Extend both of them to %12d.
Test Plan: run one test in db_test and see the LOG file.
Reviewers: igor, MarkCallaghan, ljin
Reviewed By: ljin
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D28041
Summary: BaseReferencedVersionBuilder now unreference version before destructing VersionBuilder, which is wrong. Fix it.
Test Plan:
make all check
valgrind test to tests that used to fail
Reviewers: igor, yhchiang, rven, ljin
Reviewed By: ljin
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D28101
Summary:
...and fix all the errors :)
Jim suggested turning on -Wshadow because it helped him fix number of critical bugs in fbcode. I think it's a good idea to be -Wshadow clean.
Test Plan: compiles
Reviewers: yhchiang, rven, sdong, ljin
Reviewed By: ljin
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27711
Summary:
Rename Version::Builder to VersionBuilder and expose its definition to a header.
Make VerisonBuilder not reference Version or ColumnFamilyData, only working with VersionStorageInfo.
Add version_builder_test which has a simple test.
Test Plan: make all check
Reviewers: rven, yhchiang, igor, ljin
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D27969
Summary: Apply InfoLogLevel to the logs in db/db_iter.cc
Test Plan: make
Reviewers: igor, ljin, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27861
Summary: CompactionPickerTest.Level1Trigger2 now depends on the STL implementation to be correct. Fix it.
Test Plan: Run the test
Reviewers: ljin, yhchiang, rven, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D27963
Summary: Decoupling code that deals with archived log files outside of DBImpl. That will make this code easier to reason about and test. It will also make the code easier to improve, because an improver doesn't have to understand DBImpl code in entirety.
Test Plan: added test
Reviewers: ljin, yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27873
Summary:
comparator_db_test now adds verification for three more comparators:
(1) one that store double as string
(2) one that cast uint64 to string
(3) one that concatenate two strings, prefixing their sizes.
(4) one that order by hash of the string
Test Plan:
Run ./comparator_db_test
Reviewers: ljin, yhchiang, rven, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D27927
Summary:
Increase the level size so that impact of a single file is smaller.
Also relax the bound
Test Plan: ran locally
Reviewers: sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27939
Summary: Add a new unit test in compaction_picker_test to make sure level-based compaction to pick up the level with the largest score.
Test Plan: Run the new test
Reviewers: ljin, yhchiang, rven, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D27933
Summary:
Add some helper functions to make sure DB works well for non-default comparators.
Add a test for SimpleSuffixReverseComparator.
Test Plan: Run the new test
Reviewers: ljin, rven, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D27831
Summary:
Make compaction picker easier to test.
The basic idea is to separate a minimum subcomponent of Version to VersionStorageInfo, which just responsible to LSM tree. A stub VersionStorageInfo can then be easily created and passed into compaction picker so that we can check the outputs.
It now passes most tests. Still two things need to be done:
(1) deal with the FIFO compaction's file size.
(2) write an example test to make sure the interface can do the job.
Add a compaction_picker_test to make sure compaction picker codes can be easily unit tested.
Test Plan:
Pass all unit tests and compaction_picker_test
Reviewers: yhchiang, rven, igor, ljin
Reviewed By: ljin
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D27639
Summary: Apply InfoLogLevel to the logs in db/transaction_log_impl.h
Test Plan: make
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27867
Summary: Apply InfoLogLevel to the logs in db/repair.cc
Test Plan: make
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27855
Summary: Apply InfoLogLevel to the logs in db/flush_job.cc
Test Plan: make
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27849
Summary: Apply InfoLogLevel to the logs in db/column_family.cc
Test Plan: make
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27843
Summary: Apply InfoLogLevel to the logs in db/compaction_picker.cc
Test Plan: make
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27837
Summary: Apply InfoLogLevel to the logs in db/db_filesnapshot.cc
Test Plan: make
Reviewers: ljin, sdong, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27813
Summary:
So now all open() in db_test should get options from callsite. And
destroy() always uses the last used options saved on open()
I will start to integrate env_mem in the next diff
Test Plan: make all check -j32
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27819
Summary: as title
Test Plan: as part 1
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27789
Summary: as title
Test Plan: same as part 1
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27705
Summary: as title
Test Plan: same as part 1
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27693
Summary:
DBTest has several functions (Reopen(), TryReopen(), ChangeOptins(), etc
that takes a pointer to options), depending on if it is nullptr, it uses
different options underneath. This makes it really hard to track what
options is used in different test case. We should just kill the default
value and make it being passed into explicitly. It is going to be very
hairy. I will start with simple ones.
Test Plan:
make db_test
stacked diffs, will run test with full stack
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27687
Summary:
This diff replaces BlockBasedTable in flush_job_test with TableMock, making it depend on less things and making it closer to an unit test than integration test.
It also introduces a framework to compile mock classes -- Any file named *mock.cc will not be compiled into the build. It will only get compiled into the tests. What way we can mock out most other classes, Version, VersionSet, DBImpl, etc.
Test Plan: flush_job_test
Reviewers: ljin, rven, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27681
Summary:
This diff has two fixes.
1. Fix the bug where compaction does not fail when RocksDB can't create a new file.
2. When NewWritableFiles() fails in OpenCompactionOutputFiles(), previously such fail-to-created file will be still be included as a compaction output. This patch also fixes this bug.
3. Allow VersionEdit::EncodeTo() to return Status and add basic check.
Test Plan:
./version_edit_test
export ROCKSDB_TESTS=FileCreationRandomFailure
./db_test
Reviewers: ljin, sdong, nkg-, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D25581
Summary:
Abstract out FlushProcess and take it out of DBImpl.
This also includes taking DeletionState outside of DBImpl.
Currently this diff is only doing the refactoring. Future work includes:
1. Decoupling flush_process.cc, make it depend on less state
2. Write flush_process_test, which will mock out everything that FlushProcess depends on and test it in isolation
Test Plan: make check
Reviewers: rven, yhchiang, sdong, ljin
Reviewed By: ljin
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27561
Summary: No need to expose them in .h
Test Plan: make release
Reviewers: igor, yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27645
Summary: as title
Test Plan:
make release
will run full test on all stacked diffs
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27597
Summary: as title
Test Plan:
make release
will run full test on all stacked diffs before committing
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27591
Summary:
We have several different types of data structures for file information.
FileLevel is kinda of confusing since it only contains file range and
fd. Rename it to LevelFilesBrief to make it clear.
Unfriend CompactedDBImpl as a by product
Test Plan:
make release / make all
will run full test with all stacked diffs
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27585
Summary: as title
Test Plan:
make release
I will run make all check for all stacked diffs before commit
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27573
Summary: as title
Test Plan: running make all check
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D27549
Summary: RocksDB already depends on C++11, so we might as well all the goodness that C++11 provides. This means that we don't need AtomicPointer anymore. The less things in port/, the easier it will be to port to other platforms.
Test Plan: make check + careful visual review verifying that NoBarried got memory_order_relaxed, while Acquire/Release methods got memory_order_acquire and memory_order_release
Reviewers: rven, yhchiang, ljin, sdong
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D27543
Summary:
Make inplace_update_support and inplace_update_num_locks dynamic.
inplace_callback becomes immutable
We are almost free of references to cfd->options() in db_impl
Test Plan: unit test
Reviewers: igor, yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D25293
Summary: D24513 introduced a bug that a variable is not initialized. It also causes valgrind issue.
Test Plan: Run tests used to fail valgrind and make sure it passes
Reviewers: yhchiang, ljin, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D25569
Summary:
Previously, the log for Universal Compaction does not include the current
number of files in case the compaction is triggered by the number of files.
This diff includes the number of files in the log.
Test Plan:
make
Summary: as title
Test Plan: unit test
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D25347
Summary: as title
Test Plan: n/a
Reviewers: yhchiang, sdong, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24963
Summary:
This is not a critical options. Making it dynamic so that we can remove
more reference to cfd->options()
Test Plan: unit test
Reviewers: yhchiang, sdong, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24957
Summary: Now --bench_size is only used in multireadrandom tests, although the codes allow it to run in all write tests. I don't see a reason why we can't enable it.
Test Plan:
Run
./db_bench -benchmarks multirandomwrite --threads=5 -batch_size=16
and see the stats printed out in LOG to make sure batching really happened.
Reviewers: ljin, yhchiang, rven, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D25509
Summary: It is useful to print out number of keys in DB Stats
Test Plan:
./db_bench --benchmarks fillrandom --num 1000000 -threads 16 -batch_size=16
and watch the outputs in LOG files
Reviewers: MarkCallaghan, ljin, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24513
Summary:
DeleteFile() call was broken for non-default column family. This fixes it. We might need this feature for mongo.
I also introduced a possibility of deleting oldest file in level 0.
Test Plan: added unit test to deletefile_test
Reviewers: ljin, yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24909
Summary:
Add a function as tittle.
Also use the same parameter to fillseekseq too.
Test Plan: Run seekrandom using the new parameter
Reviewers: ljin, MarkCallaghan
Reviewed By: MarkCallaghan
Subscribers: rven, igor, yhchiang, leveldb
Differential Revision: https://reviews.facebook.net/D25035
Summary:
This diff speeds up DB::Open() and Version creation by limiting the number of FileMetaData initialization. The behavior of Version::UpdateAccumulatedStats() is changed as follows:
* It only initializes the first 20 uninitialized FileMetaData from file. This guarantees the size of the latest 20 files will always be compensated when they have any deletion entries. Previously it may initialize all FileMetaData by loading all files at DB::Open().
* In case none the first 20 files has any data entry, UpdateAccumulatedStats() will initialize the FileMetaData of the oldest file.
Test Plan: db_test
Reviewers: igor, sdong, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24255
Summary:
Fix the following Mac compile error.
db/db_test.cc:8686:52: error: C++11 forbids default arguments for lambda expressions [-Werror,-Wlambda-extensions]
auto gen_l0_kb = [this](int start, int size, int stride = 1) {
^ ~
Test Plan:
db_test
Summary: as title
Test Plan: make release
Reviewers: igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D25029
Summary: Added one new counter for GetProperty
Test Plan: Not sure if needs a test case. compiles
Reviewers: sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D25023
Summary: as title
Test Plan: make release
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24903
Summary: as title
Test Plan:
unit test
I am only able to build the test case for hard_rate_limit.
soft_rate_limit is essentially the same thing as hard_rate_limit
Reviewers: igor, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24759
Summary: Add more tests as well
Test Plan: unit test
Reviewers: igor, sdong, yhchiang
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24747
Summary: as title
Test Plan: unit test
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24729
Summary:
Fixed the following compile error on Mac.
db/db_test.cc:8618:52: error: C++11 forbids default arguments for lambda expressions [-Werror,-Wlambda-extensions]
auto gen_l0_kb = [this](int start, int size, int stride = 1) {
^ ~
1 error generated.
Test Plan:
db_test
Summary: option max_background_flushes doesn't make sense if thread pool size is not set accordingly. Set the thread pool size as what we do for max_background_compactions.
Test Plan: Run db_bench with max_background_flushes > 1
Reviewers: yhchiang, igor, rven, ljin
Reviewed By: ljin
Subscribers: MarkCallaghan, leveldb
Differential Revision: https://reviews.facebook.net/D24717
Summary:
This diff introduces the `lookahead` argument to `SkipListFactory()`. This is an
optimization for the tailing use case which includes many seeks. E.g. consider
the following operations on a skip list iterator:
Seek(x), Next(), Next(), Seek(x+2), Next(), Seek(x+3), Next(), Next(), ...
If `lookahead` is positive, `SkipListRep` will return an iterator which also
keeps track of the previously visited node. Seek() then first does a linear
search starting from that node (up to `lookahead` steps). As in the tailing
example above, this may require fewer than ~log(n) comparisons as with regular
skip list search.
Test Plan:
Added a new benchmark (`fillseekseq`) which simulates the usage pattern. It
first writes N records (with consecutive keys), then measures how much time it
takes to read them by calling `Seek()` and `Next()`.
$ time ./db_bench -num 10000000 -benchmarks fillseekseq -prefix_size 1 \
-key_size 8 -write_buffer_size $[1024*1024*1024] -value_size 50 \
-seekseq_next 2 -skip_list_lookahead=0
[...]
DB path: [/dev/shm/rocksdbtest/dbbench]
fillseekseq : 0.389 micros/op 2569047 ops/sec;
real 0m21.806s
user 0m12.106s
sys 0m9.672s
$ time ./db_bench [...] -skip_list_lookahead=2
[...]
DB path: [/dev/shm/rocksdbtest/dbbench]
fillseekseq : 0.153 micros/op 6540684 ops/sec;
real 0m19.469s
user 0m10.192s
sys 0m9.252s
Reviewers: ljin, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb, march, lovro
Differential Revision: https://reviews.facebook.net/D23997
Summary: This will be much easier than reviewing git sha's we currently have in our LOGs
Test Plan: none
Reviewers: sdong, yhchiang, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24591
Summary:
The test only covers changing write_buffer_size. Other changable
parameters such bloom bits/probes are not obvious how to test.
Suggestions are welcome
Test Plan: db_test
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24429
Summary:
Fix a check in database shutdown or Column family drop during flush.
Special thanks to Maurice Barnum who spots the problem :)
Test Plan: db_test
Reviewers: ljin, igor, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24273
Summary:
Add two stats to compaction summary:
1. Total input records from previous level
2. Total number of records dropped after compaction
Test Plan: See outputs of printing when runnning locally
Reviewers: ljin, igor, MarkCallaghan
Reviewed By: MarkCallaghan
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24411
Summary: perf_context.get_from_output_files_time is now only set writable DB's DB::Get(). Extend it to MultiGet() and read only DB.
Test Plan:
make all check
Fix perf_context_test and extend it to cover MultiGet(), as long as read-only DB. Run it and watch the results
Reviewers: ljin, yhchiang, igor
Reviewed By: igor
Subscribers: rven, leveldb
Differential Revision: https://reviews.facebook.net/D24207
Summary:
Fixed signed-unsigned comparison warning in db_test.cc
db/db_test.cc:8606:3: note: in instantiation of function template specialization 'rocksdb::test::Tester::IsEq<int, unsigned long>' requested here
ASSERT_EQ(2, metadata.size());
^
Test Plan:
make db_test
Summary:
Fixed compile warning caused by unused variables.
./db/compaction_picker.h:118:7: error: private field 'max_grandparent_overlap_factor_' is not used [-Werror,-Wunused-private-field]
int max_grandparent_overlap_factor_;
^
./db/compaction_picker.h:119:7: error: private field 'expanded_compaction_factor_' is not used [-Werror,-Wunused-private-field]
int expanded_compaction_factor_;
^
2 errors generated.
Test Plan:
make db_test
Summary:
Since ForwardIterator is on a level below DBIter, the latter may call Next() on
it (e.g. in order to skip deletion markers). Since this also updates
`prev_key_`, it may prevent the Seek() optimization.
For example, assume that there's only one SST file and it contains the following
entries: 0101, 0201 (`ValueType::kTypeDeletion`, i.e. a tombstone record), 0201
(`kTypeValue`), 0202. Memtable is empty. `Seek(0102)` will result in `prev_key_`
being set to `0201` instead of `0102`, since `DBIter::Seek()` will call
`ForwardIterator::Next()` to skip record 0201. Therefore, when `Seek(0102)` is
called again, `NeedToSeekImmutable()` will return true.
This fix relies on `prefix_extractor_` to detect prefix changes. `prev_key_` is
only set to `current_->key()` as long as they have the same prefix.
I also made a small change to `NeedToSeekImmutable()` so it no longer returns
true when the db is empty (i.e. there's nothing but a memtable).
Test Plan:
$ TEST_TMPDIR=/dev/shm/rocksdbtest ROCKSDB_TESTS=TailingIterator ./db_test
Reviewers: sdong, igor, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23823
Summary:
make compaction related options changeable. Most of changes are tedious,
following the same convention: grabs MutableCFOptions at the beginning
of compaction under mutex, then pass it throughout the job and register
it in SuperVersion at the end.
Test Plan: make all check
Reviewers: igor, yhchiang, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23349
Fix for:
[db/version_set.cc:1219]: (style) Unsigned variable 'last_file'
can't be negative so it is unnecessary to test it.
[db/version_set.cc:1234]: (style) Unsigned variable 'first_file'
can't be negative so it is unnecessary to test it.
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Fix for:
[db/compaction_picker.cc:923]: (style) Unsigned variable
'start_index' can't be negative so it is unnecessary to test it.
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Fix for:
[db/db_impl.cc:4039]: (error) Instance of 'StopWatch' object is
destroyed immediately.
[db/db_impl.cc:4042]: (error) Instance of 'StopWatch' object is
destroyed immediately.
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Use empty() since it should be prefered as it has, following
the standard, a constant time complexity regardless of the
containter type. The same is not guaranteed for size().
Fix for:
[db/version_set.cc:2250]: (performance) Possible inefficient
checking for 'column_families_not_found' emptiness.
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Fix for:
[db/db_test.cc:6141]: (performance) Function parameter
'key' should be passed by reference.
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Fix for:
[db/corruption_test.cc:134]: (performance) Function parameter
'fname' should be passed by reference.
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
It seems that a FlushMemTable() call is needed in the
Uint64Comparator test after call Delete(). Otherwise the later
via Put() added keys get lost with the next FlushMemTable()
call before the check.
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Summary:
From this line there used to be one column (MB/sec) that includes reads and writes. This change splits it and for real workloads the rd and wr rates might not match when keys are dropped.
2014/09/29-17:31:01.213162 7f929fbff700 (Original Log Time 2014/09/29-17:31:01.180025) [default] compacted to: files[2 5 0 0 0 0 0], MB/sec: 14.0 rd, 14.0 wr, level 1, files in(4, 0) out(5) MB in(8.5, 0.0) out(8.5), read-write-amplify(2.0) write-amplify(1.0) OK
Test Plan:
make check, grepped LOG
- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -
Reviewers: igor
Differential Revision: https://reviews.facebook.net/D24237
Summary: Building master on OS X has some compile errors due to implicit type conversions which generate warnings which RocksDB's build settings raise as errors.
Test Plan: It compiles!
Reviewers: ljin, igor
Reviewed By: ljin
Differential Revision: https://reviews.facebook.net/D24135
Summary: see above
Test Plan:
make check, ran db_bench and looked at output
- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -
Reviewers: igor
Differential Revision: https://reviews.facebook.net/D24189
Summary:
info_log from supplied Options can be nullptr. Using the one from
db_impl. Also call flush after that since no more loggging will happen
and LOG can contain partial output
Test Plan: verified with db_bench
Reviewers: igor, yhchiang, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24183
Summary:
Intead of passing callback function pointer and its arg on Table::Get()
interface, passing GetContext. This makes the interface cleaner and
possible better perf. Also adding a fast pass for SaveValue()
Test Plan: make all check
Reviewers: igor, yhchiang, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D24057
Summary: There is a possible overflow case in universal compaction picker. Use double to make the logic straight-forward
Test Plan: make all check
Reviewers: yhchiang, igor, MarkCallaghan, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23817
Summary:
Add the MultiGet API to allow prefetching.
With file size of 1.5G, I configured it to have 0.9 hash ratio that can
fill With 115M keys and result in 2 hash functions, the lookup QPS is
~4.9M/s vs. 3M/s for Get().
It is tricky to set the parameters right. Since files size is determined
by power-of-two factor, that means # of keys is fixed in each file. With
big file size (thus smaller # of files), we will have more chance to
waste lot of space in the last file - lower space utilization as a
result. Using smaller file size can improve the situation, but that
harms lookup speed.
Test Plan: db_bench
Reviewers: yhchiang, sdong, igor
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23673
Summary:
Add a CompactedDBImpl that will enabled when calling OpenForReadOnly()
and the DB only has one level (>0) of files. As a performan comparison,
CuckooTable performs 2.1M/s with CompactedDBImpl vs. 1.78M/s with
ReadOnlyDBImpl.
Test Plan: db_bench
Reviewers: yhchiang, igor, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23553
Summary: While debugging clients compaction issues, I noticed bunch of delete bugs: P16329995. MakeTableName returns sst file with "/" prefix. We also need "/" prefix when we get the files though GetChildren(), so that we can properly dedup the files.
Test Plan: none
Reviewers: sdong, yhchiang, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23457
Summary:
Now the file summary is too small for printing. Enlarge it.
To enable it, allow to pass a size to log buffer.
Test Plan:
Add a unit test.
make all check
Reviewers: ljin, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D21723
Summary:
Previously, one single column family is given to WriteBatchWithIndex to index keys for all column families. An extra map from column family ID to comparator is maintained which can override the default comparator given in the constructor. A WriteBatchWithIndex::SetComparatorForCF() is added for user to add comparators per column family.
Also move more codes into anonymous namespace.
Test Plan: Add a unit test
Reviewers: ljin, igor
Reviewed By: igor
Subscribers: dhruba, leveldb, yhchiang
Differential Revision: https://reviews.facebook.net/D23355
Summary: It contrains the file size to be 4G max with int
Test Plan:
tried to grep instance and made sure other related variables are also
uint64
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23697
Summary:
Compaction creates backup_input iterator even though it only needed
when compaction filter v2 is enabled
Test Plan: make all check
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23769
Summary: Use PRIu64 to format uint64 in a portable manner
Test Plan: Run "make all check"
Reviewers: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23595
Summary: Those were introduced with 2fb1fea30f because the flushing behavior changed when max_background_flushes is > 0.
Test Plan: make check
Reviewers: ljin, yhchiang, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23577
Summary:
MurmurHash becomes expensive when we do millions Get() a second in one
thread. Add this option to allow the first hash function to use identity
function as hash function. It results in QPS increase from 3.7M/s to
~4.3M/s. I did not observe improvement for end to end RocksDB
performance. This may be caused by other bottlenecks that I will address
in a separate diff.
Test Plan:
```
[ljin@dev1964 rocksdb] ./cuckoo_table_reader_test --enable_perf --file_dir=/dev/shm --write --identity_as_first_hash=0
==== Test CuckooReaderTest.WhenKeyExists
==== Test CuckooReaderTest.WhenKeyExistsWithUint64Comparator
==== Test CuckooReaderTest.CheckIterator
==== Test CuckooReaderTest.CheckIteratorUint64
==== Test CuckooReaderTest.WhenKeyNotFound
==== Test CuckooReaderTest.TestReadPerformance
With 125829120 items, utilization is 93.75%, number of hash functions: 2.
Time taken per op is 0.272us (3.7 Mqps) with batch size of 0, # of found keys 125829120
With 125829120 items, utilization is 93.75%, number of hash functions: 2.
Time taken per op is 0.138us (7.2 Mqps) with batch size of 10, # of found keys 125829120
With 125829120 items, utilization is 93.75%, number of hash functions: 2.
Time taken per op is 0.142us (7.1 Mqps) with batch size of 25, # of found keys 125829120
With 125829120 items, utilization is 93.75%, number of hash functions: 2.
Time taken per op is 0.142us (7.0 Mqps) with batch size of 50, # of found keys 125829120
With 125829120 items, utilization is 93.75%, number of hash functions: 2.
Time taken per op is 0.144us (6.9 Mqps) with batch size of 100, # of found keys 125829120
With 104857600 items, utilization is 78.12%, number of hash functions: 2.
Time taken per op is 0.201us (5.0 Mqps) with batch size of 0, # of found keys 104857600
With 104857600 items, utilization is 78.12%, number of hash functions: 2.
Time taken per op is 0.121us (8.3 Mqps) with batch size of 10, # of found keys 104857600
With 104857600 items, utilization is 78.12%, number of hash functions: 2.
Time taken per op is 0.123us (8.1 Mqps) with batch size of 25, # of found keys 104857600
With 104857600 items, utilization is 78.12%, number of hash functions: 2.
Time taken per op is 0.121us (8.3 Mqps) with batch size of 50, # of found keys 104857600
With 104857600 items, utilization is 78.12%, number of hash functions: 2.
Time taken per op is 0.112us (8.9 Mqps) with batch size of 100, # of found keys 104857600
With 83886080 items, utilization is 62.50%, number of hash functions: 2.
Time taken per op is 0.251us (4.0 Mqps) with batch size of 0, # of found keys 83886080
With 83886080 items, utilization is 62.50%, number of hash functions: 2.
Time taken per op is 0.107us (9.4 Mqps) with batch size of 10, # of found keys 83886080
With 83886080 items, utilization is 62.50%, number of hash functions: 2.
Time taken per op is 0.099us (10.1 Mqps) with batch size of 25, # of found keys 83886080
With 83886080 items, utilization is 62.50%, number of hash functions: 2.
Time taken per op is 0.100us (10.0 Mqps) with batch size of 50, # of found keys 83886080
With 83886080 items, utilization is 62.50%, number of hash functions: 2.
Time taken per op is 0.116us (8.6 Mqps) with batch size of 100, # of found keys 83886080
With 73400320 items, utilization is 54.69%, number of hash functions: 2.
Time taken per op is 0.189us (5.3 Mqps) with batch size of 0, # of found keys 73400320
With 73400320 items, utilization is 54.69%, number of hash functions: 2.
Time taken per op is 0.095us (10.5 Mqps) with batch size of 10, # of found keys 73400320
With 73400320 items, utilization is 54.69%, number of hash functions: 2.
Time taken per op is 0.096us (10.4 Mqps) with batch size of 25, # of found keys 73400320
With 73400320 items, utilization is 54.69%, number of hash functions: 2.
Time taken per op is 0.098us (10.2 Mqps) with batch size of 50, # of found keys 73400320
With 73400320 items, utilization is 54.69%, number of hash functions: 2.
Time taken per op is 0.105us (9.5 Mqps) with batch size of 100, # of found keys 73400320
[ljin@dev1964 rocksdb] ./cuckoo_table_reader_test --enable_perf --file_dir=/dev/shm --write --identity_as_first_hash=1
==== Test CuckooReaderTest.WhenKeyExists
==== Test CuckooReaderTest.WhenKeyExistsWithUint64Comparator
==== Test CuckooReaderTest.CheckIterator
==== Test CuckooReaderTest.CheckIteratorUint64
==== Test CuckooReaderTest.WhenKeyNotFound
==== Test CuckooReaderTest.TestReadPerformance
With 125829120 items, utilization is 93.75%, number of hash functions: 2.
Time taken per op is 0.230us (4.3 Mqps) with batch size of 0, # of found keys 125829120
With 125829120 items, utilization is 93.75%, number of hash functions: 2.
Time taken per op is 0.086us (11.7 Mqps) with batch size of 10, # of found keys 125829120
With 125829120 items, utilization is 93.75%, number of hash functions: 2.
Time taken per op is 0.088us (11.3 Mqps) with batch size of 25, # of found keys 125829120
With 125829120 items, utilization is 93.75%, number of hash functions: 2.
Time taken per op is 0.083us (12.1 Mqps) with batch size of 50, # of found keys 125829120
With 125829120 items, utilization is 93.75%, number of hash functions: 2.
Time taken per op is 0.083us (12.1 Mqps) with batch size of 100, # of found keys 125829120
With 104857600 items, utilization is 78.12%, number of hash functions: 2.
Time taken per op is 0.159us (6.3 Mqps) with batch size of 0, # of found keys 104857600
With 104857600 items, utilization is 78.12%, number of hash functions: 2.
Time taken per op is 0.078us (12.8 Mqps) with batch size of 10, # of found keys 104857600
With 104857600 items, utilization is 78.12%, number of hash functions: 2.
Time taken per op is 0.080us (12.6 Mqps) with batch size of 25, # of found keys 104857600
With 104857600 items, utilization is 78.12%, number of hash functions: 2.
Time taken per op is 0.080us (12.5 Mqps) with batch size of 50, # of found keys 104857600
With 104857600 items, utilization is 78.12%, number of hash functions: 2.
Time taken per op is 0.082us (12.2 Mqps) with batch size of 100, # of found keys 104857600
With 83886080 items, utilization is 62.50%, number of hash functions: 2.
Time taken per op is 0.154us (6.5 Mqps) with batch size of 0, # of found keys 83886080
With 83886080 items, utilization is 62.50%, number of hash functions: 2.
Time taken per op is 0.077us (13.0 Mqps) with batch size of 10, # of found keys 83886080
With 83886080 items, utilization is 62.50%, number of hash functions: 2.
Time taken per op is 0.077us (12.9 Mqps) with batch size of 25, # of found keys 83886080
With 83886080 items, utilization is 62.50%, number of hash functions: 2.
Time taken per op is 0.078us (12.8 Mqps) with batch size of 50, # of found keys 83886080
With 83886080 items, utilization is 62.50%, number of hash functions: 2.
Time taken per op is 0.079us (12.6 Mqps) with batch size of 100, # of found keys 83886080
With 73400320 items, utilization is 54.69%, number of hash functions: 2.
Time taken per op is 0.218us (4.6 Mqps) with batch size of 0, # of found keys 73400320
With 73400320 items, utilization is 54.69%, number of hash functions: 2.
Time taken per op is 0.083us (12.0 Mqps) with batch size of 10, # of found keys 73400320
With 73400320 items, utilization is 54.69%, number of hash functions: 2.
Time taken per op is 0.085us (11.7 Mqps) with batch size of 25, # of found keys 73400320
With 73400320 items, utilization is 54.69%, number of hash functions: 2.
Time taken per op is 0.086us (11.6 Mqps) with batch size of 50, # of found keys 73400320
With 73400320 items, utilization is 54.69%, number of hash functions: 2.
Time taken per op is 0.078us (12.8 Mqps) with batch size of 100, # of found keys 73400320
```
Reviewers: sdong, igor, yhchiang
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23451
Summary: as title
Test Plan:
make all check
I will think a way to set up stress test for this
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23055
Summary: We currently don't test mmap reads as part of db_test. Piggyback it on kWalDir test config.
Test Plan: make check
Reviewers: ljin, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23337
Summary: This diff just moves the write thread control out of the DBImpl. I will need this as I will control column family data concurrency by only accessing some data in the write thread. That way, we won't have to lock our accesses to column family hash table (mappings from IDs to CFDs).
Test Plan: make check
Reviewers: sdong, yhchiang, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23301
Summary:
1. wrap a filter policy like what fbcode/multifeed/rocksdb/MultifeedRocksDbKey.h
to ensure that rocksdb works fine after filterpolicy interface change
Test Plan: 1. valgrind ./bloom_test
Reviewers: ljin, igor, yhchiang, dhruba, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23229
Summary:
If bg_error_ is set, that means that we mark DB read only. However, current behavior still continues the flushes and compactions, even though bg_error_ is set.
On the other hand, if bg_error_ is set, we will return Status::OK() from CompactRange(), although the compaction didn't actually succeed.
This is clearly not desired behavior. I found this when I was debugging t5132159, although I'm pretty sure these aren't related.
Also, when we're shutting down, it's dangerous to exit RunManualCompaction(), since that will destruct ManualCompaction object. Background compaction job might still hold a reference to manual_compaction_ and this will lead to undefined behavior. I changed the behavior so that we only exit RunManualCompaction when manual compaction job is marked done.
Test Plan: make check
Reviewers: sdong, ljin, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23223
Summary: Get valgrind to stop complaining about uninitialized value
Test Plan: valgrind not complaining anymore
Reviewers: sdong, yhchiang, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23289
Summary: The test makes sure that we don't call flush too often. For that, it's ok to check if we have less than 10 table files. Otherwise, the test is flaky because it's hard to estimate number of entries in the memtable before it gets flushed (any ideas?)
Test Plan: Still works, but hopefully less flaky.
Reviewers: ljin, sdong, yhchiang
Reviewed by: yhchiang
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23241
Summary:
When memtable is full it calls the registered callback. That callback then registers column family as needing the flush. Every write checks if there are some column families that need to be flushed. This completely eliminates the need for MakeRoomForWrite() function and simplifies our Write code-path.
There is some complexity with the concurrency when the column family is dropped. I made it a bit less complex by dropping the column family from the write thread in https://reviews.facebook.net/D22965. Let me know if you want to discuss this.
Test Plan: make check works. I'll also run db_stress with creating and dropping column families for a while.
Reviewers: yhchiang, sdong, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23067
Summary:
See t5106397.
Also, few more changes:
1. in unit tests, the assumption is that writes will be dropped when there is no space left on device. I changed the wording around it.
2. InvalidArgument() errors are only when user-provided arguments are invalid. When the file is corrupted, we need to return Status::Corruption
Test Plan: make check
Reviewers: sdong, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23145
Summary: Correct some comments and typos in RocksDB.
Test Plan: Inspection
Reviewers: sdong, igor
Reviewed By: igor
Differential Revision: https://reviews.facebook.net/D23133
Summary:
In column family's SanitizeOptions() [1], we make sure that min_write_buffer_number_to_merge is normal value. However, this test depended on the fact that setting min_write_buffer_number_to_merge to be bigger than max_write_buffer_number will cause a deadlock. I'm not sure how it worked before.
This diff fixes it by scheduling sleeping background task, which will actually block any attempts of flushing.
[1] https://github.com/facebook/rocksdb/blob/master/db/column_family.cc#L104
Test Plan: the test works now
Reviewers: yhchiang, sdong, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23103
Summary: To follow the coding convention and make sure when passing reference as a parameter it is also const, pass MergeContext as a pointer to mem tables.
Test Plan: make all check
Reviewers: ljin, igor
Reviewed By: igor
Subscribers: leveldb, dhruba, yhchiang
Differential Revision: https://reviews.facebook.net/D23085
Summary: Avoid creating unnecessary sst files while db opening
Test Plan: make all check
Reviewers: sdong, igor
Reviewed By: igor
Subscribers: zagfox, yhchiang, ljin, leveldb
Differential Revision: https://reviews.facebook.net/D20661
Summary: removed reference to options in WriteBatch and DBImpl::Get()
Test Plan: make all check
Reviewers: yhchiang, igor, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23049
Summary: as title
Test Plan: make release
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23007
Summary: ...
Test Plan: Can't repro the test failure, but let's see what jenkins says
Reviewers: zagfox, sdong, ljin
Reviewed By: sdong, ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23061
Summary:
all shared_ptrs are in immutable_options now. This will also make
options assignment a little cheaper
Test Plan: make release
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23001
Summary:
I found it is almost impossible to get rid of this function in a single
batch. I will take a step by step approach
Test Plan: make release
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22995
Summary:
When we have multiple column families, users can issue Flush() on every column families to make sure everything is flushes, even if some of them might be empty. By skipping the waiting for empty cases, it can be greatly speed up.
Still wait for people's comments before writing unit tests for it.
Test Plan: Will write a unit test to make sure it is correct.
Reviewers: ljin, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D22953
Summary:
Introducing WriteController, which is a source of truth about per-DB write delays. Let's define an DB epoch as a period where there are no flushes and compactions (i.e. new epoch is started when flush or compaction finishes). Each epoch can either:
* proceed with all writes without delay
* delay all writes by fixed time
* stop all writes
The three modes are recomputed at each epoch change (flush, compaction), rather than on every write (which is currently the case).
When we have a lot of column families, our current pull behavior adds a big overhead, since we need to loop over every column family for every write. With new push model, overhead on Write code-path is minimal.
This is just the start. Next step is to also take care of stalls introduced by slow memtable flushes. The final goal is to eliminate function MakeRoomForWrite(), which currently needs to be called for every column family by every write.
Test Plan: make check for now. I'll add some unit tests later. Also, perf test.
Reviewers: dhruba, yhchiang, MarkCallaghan, sdong, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22791
Summary:
1. Make filter_block.h a base class. Derive block_based_filter_block and full_filter_block. The previous one is the traditional filter block. The full_filter_block is newly added. It would generate a filter block that contain all the keys in SST file.
2. When querying a key, table would first check if full_filter is available. If not, it would go to the exact data block and check using block_based filter.
3. User could choose to use full_filter or tradional(block_based_filter). They would be stored in SST file with different meta index name. "filter.filter_policy" or "full_filter.filter_policy". Then, Table reader is able to know the fllter block type.
4. Some optimizations have been done for full_filter_block, thus it requires a different interface compared to the original one in filter_policy.h.
5. Actual implementation of filter bits coding/decoding is placed in util/bloom_impl.cc
Benchmark: base commit 1d23b5c470
Command:
db_bench --db=/dev/shm/rocksdb --num_levels=6 --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 --write_buffer_size=134217728 --max_write_buffer_number=2 --target_file_size_base=33554432 --max_bytes_for_level_base=1073741824 --verify_checksum=false --max_background_compactions=4 --use_plain_table=0 --memtablerep=prefix_hash --open_files=-1 --mmap_read=1 --mmap_write=0 --bloom_bits=10 --bloom_locality=1 --memtable_bloom_bits=500000 --compression_type=lz4 --num=393216000 --use_hash_search=1 --block_size=1024 --block_restart_interval=16 --use_existing_db=1 --threads=1 --benchmarks=readrandom —disable_auto_compactions=1
Read QPS increase for about 30% from 2230002 to 2991411.
Test Plan:
make all check
valgrind db_test
db_stress --use_block_based_filter = 0
./auto_sanity_test.sh
Reviewers: igor, yhchiang, ljin, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D20979
Summary: If we drop column family only from (single) write thread, we can be sure that nobody will drop the column family while we're writing (and our mutex is released). This greatly simplifies my patch that's getting rid of MakeRoomForWrite().
Test Plan: make check, but also running stress test
Reviewers: ljin, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22965
Summary:
That way we can see when this graph goes up and be happy.
Couple of changes:
1. title
2. fix db_bench to delete column families before deleting the DB. this was asserting when compiled in debug mode
3. don't sync manifest when disableDataSync. We discussed this offline. I can move it to separate diff if you'd like
Test Plan: ran it
Reviewers: sdong, yhchiang, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22815
Summary: as title
Test Plan: make release
Reviewers: sdong, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22935
Summary: Fix compaction bug in Cuckoo Table Builder. Use kvs_.size() instead of num_entries in FileSize() method. Also added tests.
Test Plan:
make check all
Also ran db_bench to generate multiple files.
Reviewers: sdong, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22743
Summary: fixed memory leak in unit test DBIteratorBoundTest
Test Plan: ran valgrind test on my unit test
Reviewers: sdong
Differential Revision: https://reviews.facebook.net/D22911
Summary:
PlainTable takes reference instead of a copy. Keep a copy in the test
code
Test Plan: make asan_check
Reviewers: sdong, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22899
Summary:
Simply code by removing code path which does not use Arena
from NewInternalIterator
Test Plan:
make all check
make valgrind_check
Reviewers: sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22395
Summary:
As a preparation to support updating some options dynamically, I'd like
to first introduce ImmutableOptions, which is a subset of Options that
cannot be changed during the course of a DB lifetime without restart.
ColumnFamily will keep both Options and ImmutableOptions. Any component
below ColumnFamily should only take ImmutableOptions in their
constructor. Other options should be taken from APIs, which will be
allowed to adjust dynamically.
I am yet to make changes to memtable and other related classes to take
ImmutableOptions in their ctor. That can be done in a seprate diff as
this one is already pretty big.
Test Plan: make all check
Reviewers: yhchiang, igor, sdong
Reviewed By: sdong
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D22545
1, const qualifiers on return types make no sense and will trigger a compile warning: warning: type qualifiers ignored on function return type [-Wignored-qualifiers]
2, class HistogramImpl has virtual functions and thus should have a virtual destructor
3, with some toolchain, the macro __STDC_FORMAT_MACROS is predefined and thus should be checked before define
Change-Id: I69747a03bfae88671bfbb2637c80d17600159c99
Signed-off-by: liuhuahang <liuhuahang@zerus.co>
Summary: It only covers Open() with default column family right now
Test Plan: make release
Reviewers: igor, yhchiang, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22467
Summary:
Before this diff, whenever we Write to non-existing column family, Write() would fail.
This diff adds an option to not fail a Write() when WriteBatch points to non-existing column family. MongoDB said this would be useful for them, since they might have a transaction updating an index that was dropped by another thread. This way, they don't have to worry about checking if all indexes are alive on every write. They don't care if they lose writes to dropped index.
Test Plan: added a small unit test
Reviewers: sdong, yhchiang, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22143
Summary: 1. db/db_impl.cc:2324 (DBImpl::BackgroundCompaction) should not raise bg_error_ when column family is dropped during compaction.
Test Plan: 1. db_stress
Reviewers: ljin, yhchiang, dhruba, igor, sdong
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22653
This eliminates the need to remember to call PERF_TIMER_STOP when a section has
been timed. This allows more useful design with the perf timers and enables
possible return value optimizations. Simplistic example:
class Foo {
public:
Foo(int v) : m_v(v);
private:
int m_v;
}
Foo makeFrobbedFoo(int *errno)
{
*errno = 0;
return Foo();
}
Foo bar(int *errno)
{
PERF_TIMER_GUARD(some_timer);
return makeFrobbedFoo(errno);
}
int main(int argc, char[] argv)
{
Foo f;
int errno;
f = bar(&errno);
if (errno)
return -1;
return 0;
}
After bar() is called, perf_context.some_timer would be incremented as if
Stop(&perf_context.some_timer) was called at the end, and the compiler is still
able to produce optimizations on the return value from makeFrobbedFoo() through
to main().
Summary: We need to set contbuild for this :)
Test Plan: compiles
Reviewers: sdong, yhchiang, ljin
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22701
Summary:
I have an application configured with 16 background threads. Write rates are high. L0->L1 compactions is very slow and it limits the concurrency of the system. While it's happening, other 15 threads are idle. However, when there is a need of a flush, that one thread busy with L0->L1 is doing flush, instead of any other 15 threads that are just sitting there.
This diff prevents that. If there are threads that are idle, we don't let flush preempt compaction.
Test Plan: Will run stress test
Reviewers: ljin, sdong, yhchiang
Reviewed By: sdong, yhchiang
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D22299
Summary:
When reading from kBlockCacheTier, ForwardIterator's internal child iterators
may end up in the incomplete state (read was unable to complete without doing
disk I/O). `ForwardIterator::status()` will correctly report that; however, the
iterator may be stuck in that state until all sub-iterators are rebuilt:
* `NeedToSeekImmutable()` may return false even if some sub-iterators are
incomplete
* one of the child iterators may be an empty iterator without any state other
that the kIncomplete status (created using `NewErrorIterator()`); seeking on
any such iterator has no effect -- we need to construct it again
Akin to rebuilding iterators after a superversion bump, this diff makes forward
iterator reset all incomplete child iterators when `Seek()` or `Next()` are
called.
Test Plan: TEST_TMPDIR=/dev/shm/rocksdbtest ROCKSDB_TESTS=TailingIterator ./db_test
Reviewers: igor, sdong, ljin
Reviewed By: ljin
Subscribers: lovro, march, leveldb
Differential Revision: https://reviews.facebook.net/D22575
Summary: It is too expensive to bump ticker to every key/vaue pair
Test Plan: make release
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22527
Summary:
1. remove class InternalFilterPolicy in db/dbformat.h
2. Transformation from internal key to user key is done in filter_block.cc
3. This is a preparation for patch D20979
Test Plan:
make all check
valgrind ./db_test
Reviewers: igor, yhchiang, ljin, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22509
Summary:
Based on discussions from t4982833. This is just a short-term fix, I plan to revamp manual compaction process as part of t4982812.
Also, I think we should schedule automatic compactions at the very end of manual compactions, not when we're done with one level. I made that change as part of this diff. Let me know if you disagree.
Test Plan: make check for now
Reviewers: sdong, tnovak, yhchiang, ljin
Reviewed By: yhchiang
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22401
Summary: No __thread for ios.
Test Plan: compile works for ios now
Reviewers: ljin, dhruba
Reviewed By: dhruba
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22491
Summary:
- New Uint64 comparator
- Modify Reader and Builder to take custom user comparators instead of bytewise comparator
- Modify logic for choosing unused user key in builder
- Modify iterator logic in reader
- test changes
Test Plan:
cuckoo_table_{builder,reader,db}_test
make check all
Reviewers: ljin, sdong
Reviewed By: ljin
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D22377
Summary: In DBImpl::Recover method, while loading memtables, also check if memtables are empty. Use this in DBImplReadonly to determine whether to lookup memtable or not.
Test Plan:
db_test
make check all
Reviewers: sdong, yhchiang, ljin, igor
Reviewed By: ljin
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22281
Summary: also fix HISTORY.md
Test Plan: make all check
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22437
Summary:
It was creating BlockBasedTableOptions object in a loop without calling
destroy()
Test Plan: valgrind ./c_test --leak-check=full --show-reachable=yes
Reviewers: sdong, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22431
Summary: Add a virtual function in table factory that will print table options
Test Plan: make release
Reviewers: igor, yhchiang, sdong
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D22149
Summary:
I will move compression related options in a separate diff since this
diff is already pretty lengthy.
I guess I will also need to change JNI accordingly :(
Test Plan: make all check
Reviewers: yhchiang, igor, sdong
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D21915
Igor Canadi