Commit Graph

723 Commits

Author SHA1 Message Date
Siying Dong
18df47b79a Avoid malloc in NotFound key status if no message is given.
Summary:
In some places we have NotFound status created with empty message, but it doesn't avoid a malloc. With this patch, the malloc is avoided for that case.

The motivation of it is that I found in db_bench readrandom test when all keys are not existing, about 4% of the total running time is spent on malloc of Status, plus a similar amount of CPU spent on free of them, which is not necessary.

Test Plan: make all check

Reviewers: dhruba, haobo, igor

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14691
2013-12-26 16:23:10 -08:00
kailiu
079a21ba99 Fix the unused variable warning message in mac os 2013-12-26 15:12:30 -08:00
Haobo Xu
bf4a48ccb3 [RocksDB] [Performance Branch] Revert previous patch.
Summary: The previous patch is wrong. rep_.resize(kHeader) just resets the header portion to zero, and should not cause a re-allocation if g++ does it right. I will go ahead and revert it.

Test Plan: make check

Reviewers: dhruba, sdong

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14793
2013-12-20 18:20:06 -08:00
Haobo Xu
e94eea4527 [RocksDB] [Performance Branch] Minor fix, Remove string resize from WriteBatch::Clear
Summary: tmp_batch_ will get re-allocated for every merged write batch because of the existing resize in WriteBatch::Clear. Note that in DBImpl::BuildBatchGroup, we have a hard coded upper limit of batch size 1<<20 = 1MB already.

Test Plan: make check

Reviewers: dhruba, sdong

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14787
2013-12-20 16:29:05 -08:00
Siying Dong
abaf26266d [RocksDB] [Performance Branch] Some Changes to PlainTable format
Summary:
Some changes to PlainTable format:
(1) support variable key length
(2) use user defined slice transformer to extract prefixes
(3) Run some test cases against PlainTable in db_test and table_test

Test Plan: test db_test

Reviewers: haobo, kailiu

CC: dhruba, igor, leveldb, nkg-

Differential Revision: https://reviews.facebook.net/D14457
2013-12-20 12:08:35 -08:00
Igor Canadi
1fdb3f7dc6 [RocksDB] Optimize locking for Get
Summary:
Instead of locking and saving a DB state, we can cache a DB state and update it only when it changes. This change reduces lock contention and speeds up read operations on the DB.

Performance improvements are substantial, although there is some cost in no-read workloads. I ran the regression tests on my devserver and here are the numbers:

  overwrite                    56345  ->   63001
  fillseq                      193730 ->  185296
  readrandom                   771301 -> 1219803 (58% improvement!)
  readrandom_smallblockcache   677609 ->  862850
  readrandom_memtable_sst      710440 -> 1109223
  readrandom_fillunique_random 221589 ->  247869
  memtablefillrandom           105286 ->   92643
  memtablereadrandom           763033 -> 1288862

Test Plan:
make asan_check
I am also running db_stress

Reviewers: dhruba, haobo, sdong, kailiu

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14679
2013-12-20 09:57:58 -08:00
Mark Callaghan
ca92068b12 Add 'readtocache' test
Summary:
For some tests I want to cache the database prior to running other tests on the same invocation
of db_bench. The readtocache test ignores --threads and --reads so those can be used by other tests
and it will still do a full read of --num rows with one thread. It might be invoked like:
  db_bench --benchmarks=readtocache,readrandom --reads 100 --num 10000 --threads 8

Task ID: #

Blame Rev:

Test Plan:
run db_bench

Revert Plan:

Database Impact:

Memcache Impact:

Other Notes:

EImportant:

- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14739
2013-12-18 16:54:53 -08:00
Igor Canadi
3b50b6213d Merge pull request #37 from mlin/more-c-bindings
C bindings: add a bunch of the newer options
2013-12-18 13:12:04 -08:00
Siying Dong
14995a8ff3 Move level0 sorting logic from Version::SaveTo() to Version::Finalize()
Summary: I realized that "D14409 Avoid sorting in Version::Get() by presorting them in VersionSet::Builder::SaveTo()" is not done in an optimized place. SaveTo() is usually inside mutex. Move it to Finalize(), which is called out of mutex.

Test Plan: make all check

Reviewers: dhruba, haobo, kailiu

Reviewed By: dhruba

CC: igor, leveldb

Differential Revision: https://reviews.facebook.net/D14607
2013-12-17 18:06:58 -08:00
Siying Dong
a8b8b11dc4 Get() Does Not Reserve space for to_delete memtables
Summary: It seems to be a decision tradeoff in current codes: we make a malloc for every Get() to reduce one malloc for a flush inside mutex. It takes about 5% of CPU time in readrandom tests. We might consider the tradeoff to be the other way around.

Test Plan: make all check

Reviewers: dhruba, haobo, igor

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14697
2013-12-17 17:16:16 -08:00
Mike Lin
2a2506b629 C bindings: add a bunch of the newer options 2013-12-15 13:47:06 -08:00
Kai Liu
2e9efcd6d8 Add the property block for the plain table
Summary:
This is the last diff that adds the property block to plain table.
The format resembles that of the block-based table: https://github.com/facebook/rocksdb/wiki/Rocksdb-table-format

  [data block]
  [meta block 1: stats block]
  [meta block 2: future extended block]
  ...
  [meta block K: future extended block]  (we may add more meta blocks in the future)
  [metaindex block]
  [index block: we only have the placeholder here, we can add persistent index block in the future]
  [Footer: contains magic number, handle to metaindex block and index block]
  <end_of_file>

Test Plan: extended existing property block test.

Reviewers: haobo, sdong, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14523
2013-12-13 17:18:14 -08:00
kailiu
0cd1521af5 Completely remove argv_ since no one use it
There are still warning in some other environment, just move that useless variable `argv_`
2013-12-12 16:36:38 -08:00
kailiu
0e24f97b9f Revert last commit and add "unused" attribute to suppress warning 2013-12-12 15:40:44 -08:00
kailiu
bc9b488e92 fix a warning in db_test when running make release 2013-12-12 15:35:02 -08:00
Mark Callaghan
e9e6b00d29 Add monitoring for universal compaction and add counters for compaction IO
Summary:
Adds these counters
{ WAL_FILE_SYNCED, "rocksdb.wal.synced" }
  number of writes that request a WAL sync
{ WAL_FILE_BYTES, "rocksdb.wal.bytes" },
  number of bytes written to the WAL
{ WRITE_DONE_BY_SELF, "rocksdb.write.self" },
  number of writes processed by the calling thread
{ WRITE_DONE_BY_OTHER, "rocksdb.write.other" },
  number of writes not processed by the calling thread. Instead these were
  processed by the current holder of the write lock
{ WRITE_WITH_WAL, "rocksdb.write.wal" },
  number of writes that request WAL logging
{ COMPACT_READ_BYTES, "rocksdb.compact.read.bytes" },
  number of bytes read during compaction
{ COMPACT_WRITE_BYTES, "rocksdb.compact.write.bytes" },
  number of bytes written during compaction

Per-interval stats output was updated with WAL stats and correct stats for universal compaction
including a correct value for write-amplification. It now looks like:
                               Compactions
Level  Files Size(MB) Score Time(sec)  Read(MB) Write(MB)    Rn(MB)  Rnp1(MB)  Wnew(MB) RW-Amplify Read(MB/s) Write(MB/s)      Rn     Rnp1     Wnp1     NewW    Count  Ln-stall Stall-cnt
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  0        7      464  46.4       281      3411      3875      3411         0      3875        2.1      12.1        13.8      621        0      240      240      628       0.0         0
Uptime(secs): 310.8 total, 2.0 interval
Writes cumulative: 9999999 total, 9999999 batches, 1.0 per batch, 1.22 ingest GB
WAL cumulative: 9999999 WAL writes, 9999999 WAL syncs, 1.00 writes per sync, 1.22 GB written
Compaction IO cumulative (GB): 1.22 new, 3.33 read, 3.78 write, 7.12 read+write
Compaction IO cumulative (MB/sec): 4.0 new, 11.0 read, 12.5 write, 23.4 read+write
Amplification cumulative: 4.1 write, 6.8 compaction
Writes interval: 100000 total, 100000 batches, 1.0 per batch, 12.5 ingest MB
WAL interval: 100000 WAL writes, 100000 WAL syncs, 1.00 writes per sync, 0.01 MB written
Compaction IO interval (MB): 12.49 new, 14.98 read, 21.50 write, 36.48 read+write
Compaction IO interval (MB/sec): 6.4 new, 7.6 read, 11.0 write, 18.6 read+write
Amplification interval: 101.7 write, 102.9 compaction
Stalls(secs): 142.924 level0_slowdown, 0.000 level0_numfiles, 0.805 memtable_compaction, 0.000 leveln_slowdown
Stalls(count): 132461 level0_slowdown, 0 level0_numfiles, 3 memtable_compaction, 0 leveln_slowdown

Task ID: #3329644, #3301695

Blame Rev:

Test Plan:
Revert Plan:

Database Impact:

Memcache Impact:

Other Notes:

EImportant:

- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14583
2013-12-12 13:27:43 -08:00
Siying Dong
e8ab1934d9 [RocksDB Performance Branch] DBImpl.NewInternalIterator() to reduce works inside mutex
Summary: To reduce mutex contention caused by DBImpl.NewInternalIterator(), in this function, move all the iteration creation works out of mutex, only leaving object ref and get.

Test Plan:
make all check
will run db_stress for a while too to make sure no problem.

Reviewers: haobo, dhruba, kailiu

Reviewed By: haobo

CC: igor, leveldb

Differential Revision: https://reviews.facebook.net/D14589
2013-12-12 11:30:00 -08:00
Siying Dong
aaf9c6203c [RocksDB][Performance Branch]Iterator Cleanup method only tries to find obsolete files if it has the last reference to a version
Summary: When deconstructing an iterator, no need to check obsolete file if it doesn't hold last reference of any version.

Test Plan: make all check

Reviewers: haobo, igor, dhruba, kailiu

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14595
2013-12-11 13:59:43 -08:00
Siying Dong
a8029fdc75 Introduce MergeContext to Lazily Initialize merge operand list
Summary: In get operations, merge_operands is only used in few cases. Lazily initialize it can reduce average latency in some cases

Test Plan: make all check

Reviewers: haobo, kailiu, dhruba

Reviewed By: haobo

CC: igor, nkg-, leveldb

Differential Revision: https://reviews.facebook.net/D14415

Conflicts:
	db/db_impl.cc
	db/memtable.cc
2013-12-11 11:37:28 -08:00
Siying Dong
bc5dd19b14 [RocksDB Performance Branch] Avoid sorting in Version::Get() by presorting them in VersionSet::Builder::SaveTo()
Summary: Pre-sort files in VersionSet::Builder::SaveTo() so that when getting the value, no need to sort them. It can avoid the costs of vector operations and sorting in Version::Get().

Test Plan: make all check

Reviewers: haobo, kailiu, dhruba

Reviewed By: dhruba

CC: nkg-, igor, leveldb

Differential Revision: https://reviews.facebook.net/D14409
2013-12-11 10:50:09 -08:00
Siying Dong
41349d9ef1 [RocksDB Performance Branch] Avoid sorting in Version::Get() by presorting them in VersionSet::Builder::SaveTo()
Summary: Pre-sort files in VersionSet::Builder::SaveTo() so that when getting the value, no need to sort them. It can avoid the costs of vector operations and sorting in Version::Get().

Test Plan: make all check

Reviewers: haobo, kailiu, dhruba

Reviewed By: dhruba

CC: nkg-, igor, leveldb

Differential Revision: https://reviews.facebook.net/D14409
2013-12-11 10:49:49 -08:00
Siying Dong
0304e3d2ff When flushing mem tables, create iterators out of mutex
Summary:
creating new iterators of mem tables can be expensive. Move them out of mutex.
DBImpl::WriteLevel0Table()'s mems seems to be a local vector and is only used by flushing. memtables to flush are also immutable, so it should be safe to do so.

Test Plan: make all check

Reviewers: haobo, dhruba, kailiu

Reviewed By: dhruba

CC: igor, leveldb

Differential Revision: https://reviews.facebook.net/D14577

Conflicts:
	db/db_impl.cc
2013-12-11 10:02:17 -08:00
Siying Dong
95a411d853 When flushing mem tables, create iterators out of mutex
Summary:
creating new iterators of mem tables can be expensive. Move them out of mutex.
DBImpl::WriteLevel0Table()'s mems seems to be a local vector and is only used by flushing. memtables to flush are also immutable, so it should be safe to do so.

Test Plan: make all check

Reviewers: haobo, dhruba, kailiu

Reviewed By: dhruba

CC: igor, leveldb

Differential Revision: https://reviews.facebook.net/D14577
2013-12-11 09:57:19 -08:00
Haobo Xu
3c02c363b3 [RocksDB] [Performance Branch] Added dynamic bloom, to be used for memable non-existing key filtering
Summary: as title

Test Plan: dynamic_bloom_test

Reviewers: dhruba, sdong, kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14385
2013-12-11 00:15:14 -08:00
kailiu
a82f42b765 rename db/memtablelist.{h,cc} 2013-12-10 19:03:13 -08:00
Igor Canadi
204bb9cffd Get rid of LogFlush() in InternalIterator 2013-12-10 10:59:00 -08:00
Igor Canadi
19f5463d3f Don't LogFlush() in foreground threads
Summary: So fflush() takes a lock which is heavyweight. I added flush_pending_, but more importantly, I removed LogFlush() from foreground threads.

Test Plan: ./db_test

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14535
2013-12-10 10:57:46 -08:00
Igor Canadi
a204dabb9d Merge pull request #31 from sepeth/c-api
Rename leveldb to rocksdb in C api
2013-12-10 09:18:47 -08:00
Doğan Çeçen
6c4e110c8c Rename leveldb to rocksdb in C api 2013-12-10 10:48:35 +02:00
Igor Canadi
fb9fce4fc3 [RocksDB] BackupableDB
Summary:
In this diff I present you BackupableDB v1. You can easily use it to backup your DB and it will do incremental snapshots for you.
Let's first describe how you would use BackupableDB. It's inheriting StackableDB interface so you can easily construct it with your DB object -- it will add a method RollTheSnapshot() to the DB object. When you call RollTheSnapshot(), current snapshot of the DB will be stored in the backup dir. To restore, you can just call RestoreDBFromBackup() on a BackupableDB (which is a static method) and it will restore all files from the backup dir. In the next version, it will even support automatic backuping every X minutes.

There are multiple things you can configure:
1. backup_env and db_env can be different, which is awesome because then you can easily backup to HDFS or wherever you feel like.
2. sync - if true, it *guarantees* backup consistency on machine reboot
3. number of snapshots to keep - this will keep last N snapshots around if you want, for some reason, be able to restore from an earlier snapshot. All the backuping is done in incremental fashion - if we already have 00010.sst, we will not copy it again. *IMPORTANT* -- This is based on assumption that 00010.sst never changes - two files named 00010.sst from the same DB will always be exactly the same. Is this true? I always copy manifest, current and log files.
4. You can decide if you want to flush the memtables before you backup, or you're fine with backing up the log files -- either way, you get a complete and consistent view of the database at a time of backup.
5. More things you can find in BackupableDBOptions

Here is the directory structure I use:

   backup_dir/CURRENT_SNAPSHOT - just 4 bytes holding the latest snapshot
               0, 1, 2, ... - files containing serialized version of each snapshot - containing a list of files
               files/*.sst - sst files shared between snapshots - if one snapshot references 00010.sst and another one needs to backup it from the DB, it will just reference the same file
               files/ 0/, 1/, 2/, ... - snapshot directories containing private snapshot files - current, manifest and log files

All the files are ref counted and deleted immediatelly when they get out of scope.

Some other stuff in this diff:
1. Added GetEnv() method to the DB. Discussed with @haobo and we agreed that it seems right thing to do.
2. Fixed StackableDB interface. The way it was set up before, I was not able to implement BackupableDB.

Test Plan:
I have a unittest, but please don't look at this yet. I just hacked it up to help me with debugging. I will write a lot of good tests and update the diff.

Also, `make asan_check`

Reviewers: dhruba, haobo, emayanke

Reviewed By: dhruba

CC: leveldb, haobo

Differential Revision: https://reviews.facebook.net/D14295
2013-12-09 14:06:52 -08:00
kailiu
551e9428ce Merge branch 'master' into performance 2013-12-06 14:15:42 -08:00
Siying Dong
ef2211a9ca [RocksDB Performance Branch] Introduce MergeContext to Lazily Initialize merge operand list
Summary: In get operations, merge_operands is only used in few cases. Lazily initialize it can reduce average latency in some cases

Test Plan: make all check

Reviewers: haobo, kailiu, dhruba

Reviewed By: haobo

CC: igor, nkg-, leveldb

Differential Revision: https://reviews.facebook.net/D14415
2013-12-06 10:28:59 -08:00
kailiu
b1d2de4a40 Fix #26 by putting the implementation of CreateDBStatistics() to a cc file 2013-12-05 22:29:03 -08:00
kailiu
90729f8b23 Extract metaindex block from block-based table
Summary: This change will allow other table to reuse the code for meta blocks.

Test Plan: all existing unit tests passed

Reviewers: dhruba, haobo, sdong

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14475
2013-12-05 16:34:16 -08:00
Mayank Agarwal
92e8316118 Make GetDbIdentity pure virtual and also implement it for StackableDB, DBWithTTL
Summary: As title

Test Plan: make clean and make

Reviewers: igor

Reviewed By: igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14469
2013-12-05 12:02:31 -08:00
Mayank Agarwal
18802689b8 Make an API to get database identity from the IDENTITY file
Summary: This would enable rocksdb users to get the db identity without depending on implementation details(storing that in IDENTITY file)

Test Plan: db/db_test (has identity checks)

Reviewers: dhruba, haobo, igor, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14463
2013-12-04 22:39:17 -08:00
Mark Callaghan
97aa401e2f Add compression options to db_bench
Summary:
This adds 2 options for compression to db_bench:
* universal_compression_size_percent
* compression_level - to set zlib compression level
It also logs compression_size_percent at startup in LOG

Task ID: #

Blame Rev:

Test Plan:
make check, run db_bench

Revert Plan:

Database Impact:

Memcache Impact:

Other Notes:

EImportant:

- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14439
2013-12-03 14:28:48 -08:00
Sajal Jain
28a1b9b95f [rocksdb] statistics counters for memtable hits and misses
Summary:
added counters
rocksdb.memtable.hit - for memtable hit
rocksdb.memtable.miss - for memtable miss

Test Plan: db_bench tests

Reviewers: igor, dhruba, haobo

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D14433
2013-12-03 12:59:53 -08:00
Igor Canadi
eb12e47e0e Killing Transform Rep
Summary:
Let's get rid of TransformRep and it's children. We have confirmed that HashSkipListRep works better with multifeed, so there is no benefit to keeping this around.

This diff is mostly just deleting references to obsoleted functions. I also have a diff for fbcode that we'll need to push when we switch to new release.

I had to expose HashSkipListRepFactory in the client header files because db_impl.cc needs access to GetTransform() function for SanitizeOptions.

Test Plan: make check

Reviewers: dhruba, haobo, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14397
2013-12-03 12:42:15 -08:00
Igor Canadi
043fc14c3e Get rid of some shared_ptrs
Summary:
I went through all remaining shared_ptrs and removed the ones that I found not-necessary. Only GenerateCachePrefix() is called fairly often, so don't expect much perf wins.

The ones that are left are accessed infrequently and I think we're fine with keeping them.

Test Plan: make asan_check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14427
2013-12-03 11:17:58 -08:00
Dhruba Borthakur
96bc3ec297 Memtables should be deleted appropriately in the unit test.
Summary:
Memtables should be deleted appropriately in the unit test.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-12-01 21:23:44 -08:00
Dhruba Borthakur
98968ba937 Free obsolete memtables outside the dbmutex had a memory leak.
Summary:
The commit at 27bbef1180 had a memory leak
that was detected by valgrind. The memtable that has a refcount decrement
in MemTableList::InstallMemtableFlushResults was not freed.

Test Plan: valgrind ./db_test --leak-check=full

Reviewers: igor

Reviewed By: igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14391
2013-11-28 10:25:22 -08:00
Igor Canadi
35ddf18367 Don't do compression tests if we don't have compression libs
Summary: These tests fail if compression libraries are not installed.

Test Plan: Manually disabled snappy, observed tests not ran.

Reviewers: dhruba, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14379
2013-11-27 13:32:56 -08:00
Kai Liu
1966b63137 Merge branch 'master' into perf 2013-11-27 11:47:40 -08:00
Haobo Xu
4e6463ea44 [RocksDB][Performance Branch] Make height and branching factor configurable for skiplist implementation
Summary: As title. Especially, HashSkipListRepFactory will be able to specify a relatively small height, to reduce the memory overhead of one skiplist per bucket.

Test Plan: make check and test it on leaf4

Reviewers: dhruba, sdong, kailiu

CC: reconnect.grayhat, leveldb

Differential Revision: https://reviews.facebook.net/D14307
2013-11-26 21:59:36 -08:00
Dhruba Borthakur
8478f380a0 During benchmarking, I see excessive use of vector.reserve().
Summary:
This code path can potentially accumulate multiple important_files for level 0.
But for other levels, it should have only one file in the
important_files, so it is ok not to reserve excessive space, is it not?

Test Plan: make check

Reviewers: haobo

Reviewed By: haobo

CC: reconnect.grayhat, leveldb

Differential Revision: https://reviews.facebook.net/D14349
2013-11-26 07:47:08 -08:00
Dhruba Borthakur
27bbef1180 Free obsolete memtables outside the dbmutex.
Summary:
Large memory allocations and frees are costly and best done outside the
db-mutex. The memtables are already allocated outside the db-mutex but
they were being freed while holding the db-mutex.
This patch frees obsolete memtables outside the db-mutex.

Test Plan:
make check
db_stress

Unit tests pass, I am in the process of running stress tests.

Reviewers: haobo, igor, emayanke

Reviewed By: haobo

CC: reconnect.grayhat, leveldb

Differential Revision: https://reviews.facebook.net/D14319
2013-11-25 21:04:48 -08:00
Igor Canadi
3ce3658411 DB::GetOptions()
Summary: We need access to options for BackupableDB

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, reconnect.grayhat

Differential Revision: https://reviews.facebook.net/D14331
2013-11-25 15:51:50 -08:00
Igor Canadi
11c26bd4a4 [RocksDB] Interface changes required for BackupableDB
Summary: This is part of https://reviews.facebook.net/D14295 -- smaller diff that is easier to review

Test Plan: make asan_check

Reviewers: dhruba, haobo, emayanke

Reviewed By: emayanke

CC: leveldb, kailiu, reconnect.grayhat

Differential Revision: https://reviews.facebook.net/D14301
2013-11-25 12:39:23 -08:00
Dhruba Borthakur
299f5c76bb Create new log file outside the dbmutex.
Summary:
All filesystem Io should be done outside the dbmutex. There was one place
when we have to roll the transaction log that we were creating the new log file
while holding the dbmutex.

I rearranged this code so that the act of creating the new transaction log
file is done without holding the dbmutex.  I also allocate the new memtable
outside the dbmutex, this is important because creating the memtable
could be heavyweight.

Test Plan: make check and dbstress

Reviewers: haobo, igor

Reviewed By: haobo

CC: leveldb, reconnect.grayhat

Differential Revision: https://reviews.facebook.net/D14283
2013-11-25 11:23:42 -08:00
Haobo Xu
5b825d6964 [RocksDB] Use raw pointer instead of shared pointer when passing Statistics object internally
Summary: liveness of the statistics object is already ensured by the shared pointer in DB options. There's no reason to pass again shared pointer among internal functions. Raw pointer is sufficient and efficient.

Test Plan: make check

Reviewers: dhruba, MarkCallaghan, igor

Reviewed By: dhruba

CC: leveldb, reconnect.grayhat

Differential Revision: https://reviews.facebook.net/D14289
2013-11-25 10:38:15 -08:00
Siying Dong
718488abc5 Add BloomFilter to PlainTableIterator::Seek()
Summary:
This patch adds a simple bloom filter in PlainTableIterator::Seek()

Test Plan: N/A

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-11-21 22:26:39 -08:00
kailiu
0c93df912e Improve the readability of the TableProperties::ToString() 2013-11-21 17:54:23 -08:00
Siying Dong
3e35aa6412 Revert "Allow users to profile a query and see bottleneck of the query"
This reverts commit 3d8ac31d71.
2013-11-21 17:40:39 -08:00
Siying Dong
b135d01e7b Allow users to profile a query and see bottleneck of the query
Summary:
Provide a framework to profile a query in detail to figure out latency bottleneck. Currently, in Get(), Put() and iterators, 2-3 simple timing is used. We can easily add more profile counters to the framework later.

Test Plan: Enable this profiling in seveal existing tests.

Reviewers: haobo, dhruba, kailiu, emayanke, vamsi, igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14001

Conflicts:
	table/merger.cc
2013-11-21 17:39:19 -08:00
Siying Dong
3d8ac31d71 Allow users to profile a query and see bottleneck of the query
Summary:
Provide a framework to profile a query in detail to figure out latency bottleneck. Currently, in Get(), Put() and iterators, 2-3 simple timing is used. We can easily add more profile counters to the framework later.

Test Plan: Enable this profiling in seveal existing tests.

Reviewers: haobo, dhruba, kailiu, emayanke, vamsi, igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14001
2013-11-21 16:29:57 -08:00
Siying Dong
58e1956d50 [Only for Performance Branch] A Hacky patch to lazily generate memtable key for prefix-hashed memtables.
Summary:
For prefix mem tables, encoding mem table key may be unnecessary if the prefix doesn't have any key. This patch is a little bit hacky but I want to try out the performance gain of removing this lazy initialization.

In longer term, we might want to revisit the way we abstract mem tables implementations.

Test Plan: make all check

Reviewers: haobo, igor, kailiu

Reviewed By: igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14265
2013-11-20 20:49:23 -08:00
Siying Dong
b59d4d5a50 A Simple Plain Table
Summary:
A Simple plain table format. No block structure. When creating the table reader, scanning the full table to create indexes.

Test Plan:Add unit test

Reviewers:haobo,dhruba,kailiu

CC:

Task ID: #

Blame Rev:
2013-11-20 18:44:22 -08:00
Siying Dong
071fb0d77b Inline a couple of functions and put one save lazily clearing
Summary:
Machine several functions inline.
Also, in DBIter.Seek() make value cleaning up lazily done.
These are for the use case that Seek() are called lots of times but few return values.

Test Plan: make all check

Differential Revision: https://reviews.facebook.net/D14217
2013-11-20 17:32:57 -08:00
Haobo Xu
37b459f0aa [RocksDB] Test diff on performance branch
Summary: trivia comment change

Test Plan: Go through the step ofs developing under the performance branch

Reviewers: dhruba, kailiu, sdong

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14259
2013-11-20 14:34:52 -08:00
Haobo Xu
a617227a36 [RocksDB] fix prefix_test
Summary: user comparator needs to work if either input is prefix only.

Test Plan: ./prefix_test --write_buffer_size=100000 --total_prefixes=10000 --items_per_prefix=10

Reviewers: dhruba, igor

Reviewed By: igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14241
2013-11-20 09:16:23 -08:00
kailiu
6eb5649800 Move flush_block_policy from Options to TableFactory
Summary:
Previously we introduce a `flush_block_policy_factory` in Options, however, that options is strongly releated to Table based tables.
It will make more sense to move it to block based table's own factory class.

Test Plan: make check to pass existing tests

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14211
2013-11-19 22:00:48 -08:00
kailiu
1415f8820d Improve the "table stats"
Summary:
The primary motivation of the changes is to make it easier to figure out the inside of the tables.

* rename "table stats" to "table properties" since now we have more than "integers" to store in the property block.
* Add filter block size to the basic table properties.
* Whenever a table is built, we'll log the table properties (the sample output is in Test Plan).
* Make an api to expose deleted keys.

Test Plan:
Passed all existing test. and the sample output of table stats:

    ==================================================================
        Basic Properties
    ------------------------------------------------------------------
                  # data blocks: 1
                      # entries: 1

                   raw key size: 9
           raw average key size: 9
                 raw value size: 9
         raw average value size: 0

                data block size: 25
               index block size: 27
              filter block size: 18
         (estimated) table size: 70

                  filter policy: rocksdb.BuiltinBloomFilter
    ==================================================================
        User collected properties: InternalKeyPropertiesCollector
    ------------------------------------------------------------------
                    kDeletedKeys: 1
    ==================================================================

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14187
2013-11-19 16:29:42 -08:00
Igor Canadi
fc61428288 Include <unistd.h> in db_test
Summary: This is the only compile issue in Ubuntu. It might be better to include <unistd.h> only in env_posix and add Truncate function to Env, but since we use truncate only in db_test, I don't think it makes much sense.

Test Plan: Rocksdb now compiles on Ubuntu!

Reviewers: dhruba, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14127
2013-11-17 21:58:16 -08:00
Igor Canadi
de9ce7d439 Upgrading compiler to gcc4.8.1
Summary:
Finally did it - the trick was in using --dynamic-linker option. This is first step to running ASAN.

All of our code seems to compile just fine on 4.8.1. However, I still left fbcode.471.sh in the 'build_tools/' just in case.

Test Plan: make clean; make

Reviewers: dhruba, haobo, kailiu, emayanke, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14109
2013-11-17 13:52:55 -08:00
Kai Liu
75df72f2a5 Change the logic in KeyMayExist()
Summary:
Previously in KeyMayExist(), if DB::Get() returns non-Status::OK(), we assumes key may not exist.
However, as if index block is not in block cache, Status::Incomplete() will return. Worse still, if
options::filter_delete is enabled, we may falsely ignore the "delete" operation:

  https://github.com/facebook/rocksdb/blob/master/db/write_batch.cc#L217-L220

This diff fixes this bug and will let crash-test pass.

Test Plan:
Ran:

  ./db_stress --test_batches_snapshots=1 --ops_per_thread=1000000 --threads=32 --write_buffer_size=4194304 --destroy_db_initially=1 --reopen=0 --readpercent=5 --prefixpercent=45 --writepercent=35 --delpercent=5 --iterpercent=10 --db=/home/kailiu/local/newer --max_key=100000000 --disable_seek_compaction=0 --mmap_read=0 --block_size=16384 --cache_size=1048576 --open_files=500000 --verify_checksum=1 --sync=0 --disable_wal=0 --disable_data_sync=0 --target_file_size_base=2097152
--target_file_size_multiplier=2 --max_write_buffer_number=3 --max_background_compactions=20 --max_bytes_for_level_base=10485760 --filter_deletes=1

Previously we'll see crash happens very soon.

Reviewers: igor, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14115
2013-11-17 01:00:34 -08:00
kailiu
97d8e573a6 make util/env_posix.cc work under mac
Summary: This diff invoves some more complicated issues in the posix environment.

Test Plan: works under mac os. will need to verify dev box.

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14061
2013-11-16 23:44:39 -08:00
Pascal Borreli
443e04e62d Fixed typos 2013-11-16 11:21:34 +00:00
Igor Canadi
21905dd4a8 Start DeleteFileTest with clean plate
Summary:
Remove all the files from the test dir before the test. The test failed when there were some old files still in the directory, since it checks the file counts.
This is what caused jenkins' test failures. It was running fine on my machine so it was hard to repro.

Test Plan:
1. create an extra 000001.log file in the test directory
2. run a ./deletefile_test - test failes
3. patch ./deletefile_test with this
4. test succeeds

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14097
2013-11-15 16:30:23 -08:00
Igor Canadi
29c931f70b Avoid populating live set if we don't need to
Summary: Also changed some comments

Test Plan: ./deletefile_test

Reviewers: haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14091
2013-11-14 22:42:02 -08:00
Igor Canadi
a0ce3fd00a PurgeObsoleteFiles() unittest
Summary:
Created a unittest that verifies that automatic deletion performed by PurgeObsoleteFiles() works correctly.

Also, few small fixes on the logic part -- call version_set_->GetObsoleteFiles() in FindObsoleteFiles() instead of on some arbitrary positions.

Test Plan: Created a unit test

Reviewers: dhruba, haobo, nkg-

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14079
2013-11-14 18:03:57 -08:00
Vamsi Ponnekanti
94dde686bb [Merge operand meant for key K is being applied on wrong key]
Summary:
We iterate until we find a different key than original key.
ikey is pointing to next key when we break out of loop.
After the loop we apply all merge operands meant for original key
on the next key!

Test Plan:
Need to give a build to Marcin to test out.

Revert Plan: OK

Task ID: #3181932

Reviewers: haobo, emayanke, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14073
2013-11-14 17:13:24 -08:00
Igor Canadi
fda8142f29 Delete log files in the correct dir
Summary: Log files are stored in wal_dir, not dbname_

Test Plan: deletfile_test

Reviewers: nkg-

Reviewed By: nkg-

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14067
2013-11-13 14:54:54 -08:00
Kai Liu
88ba331c1a Add the index/filter block cache
Summary: This diff leverage the existing block cache and extend it to cache index/filter block.

Test Plan:
Added new tests in db_test and table_test

The correctness is checked by:

1. make check
2. make valgrind_check

Performance is test by:

1. 10 times of build_tools/regression_build_test.sh on two versions of rocksdb before/after the code change. Test results suggests no significant difference between them. For the two key operatons `overwrite` and `readrandom`, the average iops are both 20k and ~260k, with very small variance).
2. db_stress.

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, haobo, xjin

Differential Revision: https://reviews.facebook.net/D13167
2013-11-12 22:46:51 -08:00
Kai Liu
35460ccb53 Fix the string format issue
Summary:

mac and our dev server has totally differnt definition of uint64_t, therefore fixing the warning in mac has actually made code in linux uncompileable.

Test Plan:

make clean && make -j32
2013-11-12 21:05:39 -08:00
Igor Canadi
d88d8ecf80 Fix deleting files
Summary: One more fix! In some cases, our filenames start with "/". Apparently, env_ can't handle filenames with double //

Test Plan:
deletefile_test does not include this line in the LOG anymore:
2013/11/12-18:11:43.150149 7fe4a6fff700 RenameFile logfile #3 FAILED -- IO error: /tmp/rocksdbtest-3574/deletefile_test//000003.log: No such file or directory

Reviewers: dhruba, haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14055
2013-11-12 20:32:07 -08:00
kailiu
21587760b9 Fixing the warning messages captured under mac os # Consider using git commit -m 'One line title' && arc diff. # You will save time by running lint and unit in the background.
Summary: The work to make sure mac os compiles rocksdb is not completed yet. But at least we can start cleaning some warnings captured only by g++ from mac os..

Test Plan: ran make in mac os

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14049
2013-11-12 20:05:28 -08:00
Igor Canadi
9df2b217e9 Move fast and break things
Summary:
Broke the compile when I removed purge_log_after_memtable_flush.

sorrybus

Test Plan: make db_bench works now

Reviewers: haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14037
2013-11-12 12:42:42 -08:00
Igor Canadi
9bc4a26f56 Small changes in Deleting obsolete files
Summary:
@haobo's suggestions from https://reviews.facebook.net/D13827

Renaming some variables, deprecating purge_log_after_flush, changing for loop into auto for loop.

I have not implemented deleting objects outside of mutex yet because it would require a big code change - we would delete object in db_impl, which currently does not know anything about object because it's defined in version_edit.h (FileMetaData). We should do it at some point, though.

Test Plan: Ran deletefile_test

Reviewers: haobo

Reviewed By: haobo

CC: leveldb, haobo

Differential Revision: https://reviews.facebook.net/D14025
2013-11-12 11:53:26 -08:00
Igor Canadi
dad425562f Move the comment
Summary: Moving the comment per @haobo suggestion.

Test Plan: No

Reviewers: haobo

Reviewed By: haobo

CC: leveldb, haobo

Differential Revision: https://reviews.facebook.net/D14019
2013-11-12 10:07:55 -08:00
Igor Canadi
4abd219cfc Combine two FindObsoleteFiles()
Summary: We don't need to call FindObsoleteFiles() twice

Test Plan: deletefile_test

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14007
2013-11-11 21:41:32 -08:00
Igor Canadi
94e139f94d Fixing failed delete file test
Summary: FindObsoleteFiles() has to be called before PurgeObsoleteFiles() because FindObsoleteFiles() sets manifest_file_number, log_number and prev_log_number to valid values.

Test Plan: deletefile_test now works

Reviewers: dhruba, emayanke, kailiu

Reviewed By: kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13995
2013-11-11 21:03:41 -08:00
Dhruba Borthakur
318a4919d2 Fix valgrind check by initialising DeletionState.
Summary:
The valgrind error was introduced by commit
1510339e52. Initialize DeletionState
in constructor.

Test Plan: valgrind --leak-check=yes ./deletefile_test

Reviewers: igor, kailiu

Reviewed By: kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13983
2013-11-11 16:01:13 -08:00
lovro
8a46ecd357 WriteBatch::Put() overload that gathers key and value from arrays of slices
Summary: In our project, when writing to the database, we want to form the value as the concatenation of a small header and a larger payload.  It's a shame to have to copy the payload just so we can give RocksDB API a linear view of the value.  Since RocksDB makes a copy internally, it's easy to support gather writes.

Test Plan: write_batch_test, new test case

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13947
2013-11-08 16:34:32 -08:00
Igor Canadi
1510339e52 Speed up FindObsoleteFiles
Summary:
Here's one solution we discussed on speeding up FindObsoleteFiles. Keep a set of all files in DBImpl and update the set every time we create a file. I probably missed few other spots where we create a file.

It might speed things up a bit, but makes code uglier. I don't really like it.

Much better approach would be to abstract all file handling to a separate class. Think of it as layer between DBImpl and Env. Having a separate class deal with file namings and deletion would benefit both code cleanliness (especially with huge DBImpl) and speed things up. It will take a huge effort to do this, though.

Let's discuss offline today.

Test Plan: Ran ./db_stress, verified that files are getting deleted

Reviewers: dhruba, haobo, kailiu, emayanke

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D13827
2013-11-08 15:23:46 -08:00
Igor Canadi
dd218bbc88 Forgot to change interface everywhere
Summary: Changed the name and interface for creating HashSkipListRep. Forgot to change it in db_test.

Test Plan: make db_test

Reviewers: haobo

Reviewed By: haobo

Differential Revision: https://reviews.facebook.net/D13965
2013-11-08 12:23:12 -08:00
Igor Canadi
8b3379dc0a Implementing DynamicIterator for TransformRepNoLock
Summary: What @haobo done with TransformRep, now in TransformRepNoLock. Similar implementation, except that I made DynamicIterator a subclass of Iterator which makes me have less iterator initializations.

Test Plan: ./prefix_test. Seeing huge savings vs. TransformRep again!

Reviewers: dhruba, haobo, sdong, kailiu

Reviewed By: haobo

CC: leveldb, haobo

Differential Revision: https://reviews.facebook.net/D13953
2013-11-08 00:31:09 -08:00
Kai Liu
fd075d6edd Provide mechanism to configure when to flush the block
Summary: Allow block based table to configure the way flushing the blocks. This feature will allow us to add support for prefix-aligned block.

Test Plan: make check

Reviewers: dhruba, haobo, sdong, igor

Reviewed By: sdong

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13875
2013-11-07 21:27:21 -08:00
Kai Liu
bba6595b1f Fix the valgrind error
Summary: I this bug from valgrind report and found a place that may potentially leak memory.

Test Plan: re-ran the valgrind and no error any more

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13959
2013-11-07 15:46:48 -08:00
Igor Canadi
444cf88a56 Flush the log outside of lock
Summary:
Added a new call LogFlush() that flushes the log contents to the OS buffers. We never call it with lock held.

We call it once for every Read/Write and often in compaction/flush process so the frequency should not be a problem.

Test Plan: db_test

Reviewers: dhruba, haobo, kailiu, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13935
2013-11-07 11:31:56 -08:00
Haobo Xu
fd2044883a [RocksDB] Generalize prefix-aware iterator to be used for more than one Seek
Summary: Added a prefix_seek flag in ReadOptions to indicate that Seek is prefix aware(might not return data with different prefix), and also not bound to a specific prefix. Multiple Seeks and range scans can be invoked on the same iterator. If a specific prefix is specified, this flag will be ignored. Just a quick prototype that works for PrefixHashRep, the new lockless memtable could be easily extended with this support too.

Test Plan: test it on Leaf

Reviewers: dhruba, kailiu, sdong, igor

Reviewed By: igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13929
2013-11-06 20:45:49 -08:00
shamdor
c2be2cba04 WAL log retention policy based on archive size.
Summary:
Archive cleaning will still happen every WAL_ttl seconds
but archived logs will be deleted only if archive size
is greater then a WAL_size_limit value.
Empty archived logs will be deleted evety WAL_ttl.

Test Plan:
1. Unit tests pass.
2. Benchmark.

Reviewers: emayanke, dhruba, haobo, sdong, kailiu, igor

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13869
2013-11-06 18:46:28 -08:00
Igor Canadi
be96f2498e TransformRep - use array instead of unordered_map
Summary:
I'm sending this diff together with https://reviews.facebook.net/D13881 because it didn't allow me to send only the array one.

Here I also replaced unordered_map with just an array of shared_ptrs. This elminated all the locks.

I will run the new benchmark and post the results here.

Test Plan: db_test

Reviewers: dhruba, haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13893
2013-11-06 11:55:43 -08:00
Haobo Xu
fe4a449472 [RocksDB] prefixhash memtable test
Summary: as title, half baked test for prefixhash memtable. Also contains deadlock test option

Test Plan: run it

Reviewers: igor, dhruba

Reviewed By: igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13887
2013-11-05 23:20:10 -08:00
Dhruba Borthakur
39190588e1 Fix failure in rocksdb unit test CompressedCache
Summary:
The problem was that there was only a single key-value in a block
and its compressibility was less than 88%. Rocksdb refuses to
compress a block unless its compresses to lesser than 88% of its
original size. If a block is not compressed, it does nto get inserted
into the compressed block cache.

Create the test data so that multiple records fit into the same
data block. This increases the compressibility of these data block.

Test Plan: ./db_test

Reviewers: kailiu, haobo

Reviewed By: kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13905
2013-11-05 16:11:34 -08:00
Dhruba Borthakur
7845fd9db9 Fixed valgrind error in DBTest.CompressedCache
Summary:
Fixed valgrind error in DBTest.CompressedCache.
This fixes the valgrind error (thanks to Haobo). I am still trying to reproduce the test-failure case deterministically.

Test Plan: db_test

Reviewers: haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13899
2013-11-05 11:12:39 -08:00
Mayank Agarwal
f837f5b1c9 Making the transaction log iterator more robust
Summary:
strict essentially means that we MUST find the startsequence. Thus we should return if starteSequence is not found in the first file in case strict is set. This will take care of ending the iterator in case of permanent gaps due to corruptions in the log files
Also created NextImpl function that will have internal variable to distinguish whether Next is being called from StartSequence or by application.
Set NotFoudn::gaps status to give an indication of gaps happeneing.
Polished the inline documentation at various places

Test Plan:
* db_repl_stress test
* db_test relating to transaction log iterator
* fbcode/wormhole/rocksdb/rocks_log_iterator
* sigma production machine sigmafio032.prn1

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13689
2013-11-04 20:49:03 -08:00
Dhruba Borthakur
b4ad5e89ae Implement a compressed block cache.
Summary:
Rocksdb can now support a uncompressed block cache, or a compressed
block cache or both. Lookups first look for a block in the
uncompressed cache, if it is not found only then it is looked up
in the compressed cache. If it is found in the compressed cache,
then it is uncompressed and inserted into the uncompressed cache.

It is possible that the same block resides in the compressed cache
as well as the uncompressed cache at the same time. Both caches
have their own individual LRU policy.

Test Plan: Unit test case attached.

Reviewers: kailiu, sdong, haobo, leveldb

Reviewed By: haobo

CC: xjin, haobo

Differential Revision: https://reviews.facebook.net/D12675
2013-11-01 14:31:35 -07:00
Igor Canadi
beeb74be6f Move I/O outside of lock
Summary:
I'm figuring out how Version[Set, Edit, ] classes work and I stumbled on this.

It doesn't seem that the comment is accurate anymore. What I read is when the manifest grows too big, create a new file (and not only when we call LogAndApply for the first time).

Test Plan: make check (currently running)

Reviewers: dhruba, haobo, kailiu, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13839
2013-11-01 12:32:27 -07:00
Haobo Xu
8cbe5bb56b [RocksDB] Add OnCompactionStart to CompactionFilter class
Summary: This is to give application compaction filter a chance to access context information of a specific compaction run. For example, depending on whether a compaction goes through all data files, the application could do things differently.

Test Plan: make check

Reviewers: dhruba, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13683
2013-10-31 13:36:43 -07:00
Naman Gupta
b4fab3be2a Merge branch 'master' of github.com:facebook/rocksdb into inplace 2013-10-31 11:51:03 -07:00
Naman Gupta
fe25070242 In-place updates for equal keys and similar sized values
Summary:
Currently for each put, a fresh memory is allocated, and a new entry is added to the memtable with a new sequence number irrespective of whether the key already exists in the memtable. This diff is an attempt to update the value inplace for existing keys. It currently handles a very simple case:
1. Key already exists in the current memtable. Does not inplace update values in immutable memtable or snapshot
2. Latest value type is a 'put' ie kTypeValue
3. New value size is less than existing value, to avoid reallocating memory

TODO: For a put of an existing key, deallocate memory take by values, for other value types till a kTypeValue is found, ie. remove kTypeMerge.
TODO: Update the transaction log, to allow consistent reload of the memtable.

Test Plan: Added a unit test verifying the inplace update. But some other unit tests broken due to invalid sequence number checks. WIll fix them next.

Reviewers: xinyaohu, sumeet, haobo, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12423

Automatic commit by arc
2013-10-31 11:27:12 -07:00
Siying Dong
f03b2df010 Follow-up Cleaning-up After D13521
Summary:
This patch is to address @haobo's comments on D13521:
1. rename Table to be TableReader and make its factory function to be GetTableReader
2. move the compression type selection logic out of TableBuilder but to compaction logic
3. more accurate comments
4. Move stat name constants into BlockBasedTable implementation.
5. remove some uncleaned codes in simple_table_db_test

Test Plan: pass test suites.

Reviewers: haobo, dhruba, kailiu

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13785
2013-10-30 10:52:33 -07:00
Siying Dong
068a819ac9 Fix valgrind_check problem of simple_table_db_test.cc
Summary: Two memory issues caused valgrind_check to fail on simple_table_db_test. Fix it

Test Plan: make -j32 valgrind_check

Reviewers: kailiu, haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13773
2013-10-29 14:29:03 -07:00
Siying Dong
d4eec30ed0 Make "Table" pluggable
Summary: This patch makes Table and TableBuilder a abstract class and make all the implementation of the current table into BlockedBasedTable and BlockedBasedTable Builder.

Test Plan: Make db_test.cc to work with block based table. Add a new test simple_table_db_test.cc where a different simple table format is implemented.

Reviewers: dhruba, haobo, kailiu, emayanke, vamsi

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13521
2013-10-28 17:54:09 -07:00
Kai Liu
994575c134 Support user-defined table stats collector
Summary:
1. Added a new option that support user-defined table stats collection.
2. Added a deleted key stats collector in `utilities`

Test Plan:
Added a unit test for newly added code.
Also ran make check to make sure other tests are not broken.

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13491
2013-10-28 15:45:14 -07:00
Kai Liu
7e91b86f4d Fix a valgrind warning
Summary:
A latest valgrind test found a recently added unit test has memory leak,
which is because DB is not closed at the end of the test.

Test Plan: re-run the valgrind locally and make sure there's no memory leakage any more.

Reviewers: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13725
2013-10-28 14:34:27 -07:00
Igor Canadi
100fa8e013 If a Put fails, fail all other puts
Summary:
When a Put fails, it can leave database in a messy state. We don't want to pretend that everything is OK when it may not be. We fail every write following the failed one.

I added checks for corruption to DBImpl::Write(). Is there anywhere else I need to add them?

Test Plan: Corruption unit test.

Reviewers: dhruba, haobo, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13671
2013-10-28 12:36:02 -07:00
Kai Liu
a1d38a41fd fix the error message in debug mode
Summary:

my fix patch introduced a new error in debug mode.

Test Plan:

`make` and `make release`
2013-10-27 23:11:13 -07:00
Kai Liu
39c14891b6 Fix the gcc warning for unused variable
Summary: Fix the unused variable warning for `first` when running `make release`

Test Plan:
make
make check

Reviewers: dhruba, igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13695
2013-10-27 22:57:45 -07:00
Mayank Agarwal
56305221c4 Unify DeleteFile and DeleteWalFiles
Summary:
This is to simplify rocksdb public APIs and improve the code quality.
Created an additional parameter to ParseFileName for log sub type and improved the code for deleting a wal file.
Wrote exhaustive unit-tests in delete_file_test
Unification of other redundant APIs can be taken up in a separate diff

Test Plan: Expanded delete_file test

Reviewers: dhruba, haobo, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13647
2013-10-25 08:32:14 -07:00
Kai Liu
c17607a251 Fix the log number bug when updating MANIFEST file
Summary:
Crash may occur during the flushes of more than two mem tables.

As the info log suggested, even when both were successfully flushed,
the recovery process still pick up one of the memtable's log for recovery.

This diff fix the problem by setting the correct "log number" in MANIFEST.

Test Plan: make test; deployed to leaf4 and make sure it doesn't result in crashes of this type.

Reviewers: haobo, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13659
2013-10-24 21:05:33 -07:00
Slobodan Predolac
e44976b199 Conversion of db_bench, db_stress and db_repl_stress to use gflags
Summary: Converted db_stress, db_repl_stress and db_bench to use gflags

Test Plan: I tested by printing out all the flags from old and new versions. Tried defaults, + various combinations with "interesting flags". Also, tested by running db_crashtest.py and db_crashtest2.py.

Reviewers: emayanke, dhruba, haobo, kailiu, sdong

Reviewed By: emayanke

CC: leveldb, xjin

Differential Revision: https://reviews.facebook.net/D13581
2013-10-24 07:43:14 -07:00
Haobo Xu
2fb361ad98 [RocksDB] Add perf_context.wal_write_time to track time spent on writing the recovery log.
Summary: as title

Test Plan: make check; ./perf_context_test

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13629
2013-10-23 13:38:39 -07:00
Mayank Agarwal
e56ce03691 Hardcoding temp file name for Identity file to 000000.dbtmp just like it's done for CURRENT file
Summary: as per Dhruba's suggestion

Test Plan: make all check; Seen the Id getting generated properly in db_repl_stress

Reviewers: dhruba, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13635
2013-10-23 11:34:22 -07:00
Mayank Agarwal
9b50106f9a Dbid feature
Summary:
Create a new type of file on startup if it doesn't already exist called DBID.
This will store a unique number generated from boost library's uuid header file.
The use-case is to identify the case of a db losing all its data and coming back up either empty or from an image(backup/live replica's recovery)
the key point to note is that DBID is not stored in a backup or db snapshot
It's preferable to use Boost for uuid because:
1) A non-standard way of generating uuid is not good
2) /proc/sys/kernel/random/uuid generates a uuid but only on linux environments and the solution would not be clean
3) c++ doesn't have any direct way to get a uuid
4) Boost is a very good library that was already having linkage in rocksdb from third-party
Note: I had to update the TOOLCHAIN_REV in build files to get latest verison of boost from third-party as the older version had a bug.
I had to put Wno-uninitialized in Makefile because boost-1.51 has an unitialized variable and rocksdb would not comiple otherwise. Latet open-source for boost is 1.54 but is not there in third-party. I have notified the concerned people in fbcode about it.
@kailiu : While releasing to third-party, an additional dependency will need to be created for boost in TARGETS file. I can help identify.

Test Plan:
Expand db_test to test 2 cases
1) Restarting db with Id file present - verify that no change to Id
2)Restarting db with Id file deleted - verify that a different Id is there after reopen
Also run make all check

Reviewers: dhruba, haobo, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13587
2013-10-22 12:23:34 -07:00
Mayank Agarwal
ae8e0770b4 Disallow transaction log iterator to skip sequences
Summary:
This is expected to solve the "gaps in transaction log iterator" problem.
* After a lot of observations on the gaps on the sigmafio machines I found that it is due to a race between log reader and writer always.
* So when we drop the wormhole subscription and refresh the iterator, the gaps are not there.
* It is NOT due to some boundary or corner case left unattended in the iterator logic because I checked many instances of the gaps against their log files with ldb. The log files are NOT corrupted also.
* The solution is to not allow the iterator to read incompletely written sequences and detect gaps inside itself and invalidate it which will cause the application to refresh the iterator normally and seek to the required sequence properly.
* Thus, the iterator can at least guarantee that it will not give any gaps.

Test Plan:
* db_test based log iterator tests
* db_repl_stress
* testing on sigmafio setup to see gaps go away

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13593
2013-10-22 11:45:35 -07:00
Siying Dong
65428b0c0a Fix Bug: iterator.Prev() or iterator.SeekToLast() might return the first element instead of the correct one
Summary:
Recent patch https://reviews.facebook.net/D11865 introduced a regression bug:

DBIter::FindPrevUserEntry(), which is called by DBIter::Prev() (and also implicitly if calling iterator.SeekToLast())  might do issue a seek when having skipped too many entries. If the skipped entry just before the seek() is a delete, the saved key is erased so that it seeks to the front, so Prev() would return the first element.

This patch fixes the bug by not doing seek() in DBIter::FindNextUserEntry() if saved key has been erased.

Test Plan: Add a test DBTest.IterPrevMaxSkip which would fail without the patch and would pass with the change.

Reviewers: dhruba, xjin, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13557
2013-10-17 18:33:18 -07:00
Siying Dong
9edda37027 Universal Compaction to Have a Size Percentage Threshold To Decide Whether to Compress
Summary:
This patch adds a option for universal compaction to allow us to only compress output files if the files compacted previously did not yet reach a specified ratio, to save CPU costs in some cases.

Compression is always skipped for flushing. This is because the size information is not easy to evaluate for flushing case. We can improve it later.

Test Plan:
add test
DBTest.UniversalCompactionCompressRatio1 and DBTest.UniversalCompactionCompressRatio12

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13467
2013-10-17 13:33:39 -07:00
Dhruba Borthakur
9cd221094c Add appropriate LICENSE and Copyright message.
Summary:
Add appropriate LICENSE and Copyright message.

Test Plan:
make check

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-10-16 17:48:41 -07:00
Siying Dong
073cbfc8f0 Enable background flush thread by default and fix issues related to it
Summary:
Enable background flush thread in this patch and fix unit tests with:
(1) After background flush, schedule a background compaction if condition satisfied;
(2) Fix a bug that if universal compaction is enabled and number of levels are set to be 0, compaction will not be automatically triggered
(3) Fix unit tests to wait for compaction to finish instead of flush, before checking the compaction results.

Test Plan: pass all unit tests

Reviewers: haobo, xjin, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13461
2013-10-16 13:32:53 -07:00
Mayank Agarwal
da2fd001a6 Fix rocksdb->levledb BytewiseComparator and inverted order of error in db/version_set.cc
Summary:
This is needed to make existing dbs be able to open and also because BytewiseComparator was not changed since leveldb.
The inverted order in the error message caused confusion prebiously

Test Plan: make; open existing db

Reviewers: leveldb, dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D13449
2013-10-14 18:16:54 -07:00
Mayank Agarwal
fe3713961e Features in Transaction log iterator
Summary:
* Logstore requests a valid change of reutrning an empty iterator and not an error in case of no log files.
* Changed the code to return the writebatch containing the sequence number requested from GetupdatesSince even if it lies in the middle. Earlier we used to return the next writebatch,. This also allows me oto guarantee that no files played upon by the iterator are redundant. I mean the starting log file has at least a sequence number >= the sequence number requested form GetupdatesSince.
* Cleaned up redundant logic in Iterator::Next and made a new function SeekToStartSequence for greater readability and maintainibilty.
* Modified a test in db_test accordingly
Please check the logic carefully and suggest improvements. I have a separate patch out for more improvements like restricting reader to read till written sequences.

Test Plan:
* transaction log iterator tests in db_test,
* db_repl_stress.
* rocks_log_iterator_test in fbcode/wormhole/rocksdb/test - 2 tests thriving on hacks till now can get simplified
* testing on the shadow setup for sigma with replication

Reviewers: dhruba, haobo, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13437
2013-10-14 18:16:21 -07:00
Kai Liu
86ef6c3f74 Add statistics to sst file
Summary:
So far we only have key/value pairs as well as bloom filter stored in the
sst file.  It will be great if we are able to store more metadata about
this table itself, for example, the entry size, bloom filter name, etc.

This diff is the first step of this effort. It allows table to keep the
basic statistics mentioned in http://fburl.com/14995441, as well as
allowing writing user-collected stats to stats block.

After this diff, we will figure out the interface of how to allow user to collect their interested statistics.

Test Plan:
1. Added several unit tests.
2. Ran `make check` to ensure it doesn't break other tests.

Reviewers: dhruba, haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13419
2013-10-14 15:56:13 -07:00
Siying Dong
88f2f89068 Change Function names from Compaction->Flush When they really mean Flush
Summary: When I debug the unit test failures when enabling background flush thread, I feel the function names can be made clearer for people to understand. Also, if the names are fixed, in many places, some tests' bugs are obvious (and some of those tests are failing). This patch is to clean it up for future maintenance.

Test Plan: Run test suites.

Reviewers: haobo, dhruba, xjin

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13431
2013-10-14 15:12:15 -07:00
sdong
f8509653ba LRUCache to try to clean entries not referenced first.
Summary:
With this patch, when LRUCache.Insert() is called and the cache is full, it will first try to free up entries whose reference counter is 1 (would become 0 after remo\
ving from the cache). We do it in two passes, in the first pass, we only try to release those unreferenced entries. If we cannot free enough space after traversing t\
he first remove_scan_cnt_ entries, we start from the beginning again and remove those entries being used.

Test Plan: add two unit tests to cover the codes

Reviewers: dhruba, haobo, emayanke

Reviewed By: emayanke

CC: leveldb, emayanke, xjin

Differential Revision: https://reviews.facebook.net/D13377
2013-10-11 09:26:21 -07:00
Dhruba Borthakur
c0ce562c32 Bad nfs file checked in a long time back.
Summary:
Bad nfs file checked in a long time back.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-10-10 22:00:49 -07:00
Mayank Agarwal
a8b4a69de0 Fixing error in ParseFileName causing DestroyDB to fail on archive directory
Summary:
This careless error was causing ASSERT_OK(DestroyDB) to fail in db_test.
Basically .. was being returned as a child of db/archive and ParseFileName returned false on that,
but 'type' was set to LogFile from earlier and not reset. The return of ParseFileName was not being checked to delete the log file or not.

Test Plan: make all check

Reviewers: dhruba, haobo, xjin, kailiu, nkg-

Reviewed By: nkg-

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13413
2013-10-10 18:18:31 -07:00
Naman Gupta
cbf4a06427 Add option for storing transaction logs in a separate dir
Summary: In some cases, you might not want to store the data log (write ahead log) files in the same dir as the sst files. An example use case is leaf, which stores sst files in tmpfs. And would like to save the log files in a separate dir (disk) to save memory.

Test Plan: make all. Ran db_test test. A few test failing. P2785018. If you guys don't see an obvious problem with the code, maybe somebody from the rocksdb team could help me debug the issue here. Running this on leaf worked well. I could see logs stored on disk, and deleted appropriately after compactions. Obviously this is only one set of options. The unit tests cover different options. Seems like I'm missing some edge cases.

Reviewers: dhruba, haobo, leveldb

CC: xinyaohu, sumeet

Differential Revision: https://reviews.facebook.net/D13239
2013-10-08 17:40:27 -07:00
Naman Gupta
116071411b Make db_test more robust
Summary: While working on D13239, I noticed that the same options are not used for opening and destroying at db. So adding that. Also added asserts for successful DestroyDB calls.

Test Plan: Ran unit tests. Atleast 1 unit test is failing. They failures are a result of some past logic change. I'm not really planning to fix those. But I would like to check this in. And hopefully the respective unit test owners can fix the broken tests

Reviewers: leveldb, haobo

CC: xinyaohu, sumeet, dhruba

Differential Revision: https://reviews.facebook.net/D13329
2013-10-08 13:19:31 -07:00
Dhruba Borthakur
1a8c1b0817 Unit test failure in DBTest.NumImmutableMemTable.
Summary:
Previous patch introduced a unit test failure in
DBTest.NumImmutableMemTable because of change in property names.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-10-06 01:12:02 -07:00
Dhruba Borthakur
4463b11cad Migrate names of properties from 'leveldb' prefix to 'rocksdb' prefix.
Summary: Migrate names of properties from 'leveldb' prefix to 'rocksdb' prefix.

Test Plan: make check

Reviewers: emayanke, haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13311
2013-10-06 00:14:26 -07:00
Haobo Xu
bf89edf78b [RocksDB] Added a property "leveldb.num-immutable-mem-table" so that Flush can be called without blocking, and application still has a way to check when it's done also without blocking.
Summary: as title

Test Plan: DBTest.NumImmutableMemTable

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13305
2013-10-05 11:54:08 -07:00
Dhruba Borthakur
0a9f873f4b Removed scribe, thrift and java modules.
Summary: Removed scribe, thrift and java modules.

Test Plan:
make release
make check

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13293
2013-10-04 15:36:00 -07:00
Dhruba Borthakur
a143ef9b38 Change namespace from leveldb to rocksdb
Summary:
Change namespace from leveldb to rocksdb. This allows a single
application to link in open-source leveldb code as well as
rocksdb code into the same process.

Test Plan: compile rocksdb

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13287
2013-10-04 11:59:26 -07:00
Mayank Agarwal
b3ed08129b Add a statistic to count the number of calls to GetUpdatesSince
Summary: This is useful to keep track of refreshes in transaction log iterator

Test Plan: make; db_stress --statistics=1 shows it

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13281
2013-10-04 10:47:20 -07:00
Mayank Agarwal
854d236361 Add backward compatible option in GetLiveFiles to choose whether to not Flush first
Summary:
As explained in comments in GetLiveFiles in db.h, this option will cause flush to be skipped in GetLiveFiles because some use-cases use GetSortedWalFiles after GetLiveFiles to generate more complete snapshots.
Using GetSortedWalFiles after GetLiveFiles allows us to not Flush in GetLiveFiles first because wals have everything.
Note: file deletions will be disabled before calling GLF or GSWF so live logs will not move to archive logs or get delted.
Note: Manifest file is truncated to a proper value in GLF, so it will always reply from the proper wal files on a restart

Test Plan: make

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13257
2013-10-04 10:20:10 -07:00
Haobo Xu
200c05a23f [RocksDB] Still honor DisableFileDeletions when purge_log_after_memtable_flush is on
Summary: as title

Test Plan: make check

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13263
2013-10-03 16:12:43 -07:00
Haobo Xu
fa798e9e28 [Rocksdb] Submit mem table flush job in a different thread pool
Summary: As title. This is just a quick hack and not ready for commit. fails a lot of unit test. I will test/debug it directly in ViewState shadow .

Test Plan: Try it in shadow test.

Reviewers: dhruba, xjin

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12933
2013-10-03 14:37:19 -07:00
Xing Jin
658a3ce2fa Fix SIGSEGV issue in universal compaction
Summary:
We saw SIGSEGV when set options.num_levels=1 in universal compaction
style. Dug into this issue for a while, and finally found the root cause (thank Haobo for discussion).

Test Plan: Add new unit test. It throws SIGSEGV without this change. Also run "make all check".

Reviewers: haobo, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13251
2013-10-02 17:33:31 -07:00
Haobo Xu
71046971f0 [RocksDB] Added perf counters to track skipped internal keys during iteration
Summary: as title. unit test not polished. this is for a quick live test

Test Plan: live

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13221
2013-10-02 10:48:41 -07:00
Xing Jin
8eb552bf4d New unit test for iterator with snapshot
Summary:
I played with the reported bug about iterator with snapshot:
https://code.google.com/p/leveldb/issues/detail?id=200.

I turned the original test program
(https://code.google.com/p/leveldb/issues/attachmentText?id=200&aid=2000000000&name=test.cc&token=7uOUQW-HFlbAFMUm7EqtaAEy7Tw%3A1378320724136)
into a new unit test, but I cannot reproduce the problem. Notice lines
31-34 in above link. I have ran the new test with and without such Put()
operations. Both succeed.

So this diff simply adds the test, without changing any source codes.

Test Plan: run new test.

Reviewers: dhruba, haobo, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12735
2013-09-28 11:39:08 -07:00
Haobo Xu
0c4040681a [RocksDB] Move last_sequence and last_flushed_sequence_ update back into lock protected area
Summary: A previous diff moved these outside of lock protected area. Moved back in now. Also moved tmp_batch_ update outside of lock protected area, as only the single write thread can access it.

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13137
2013-09-26 20:43:11 -07:00
Haobo Xu
08740b15a4 [RocksDB] Fix skiplist sequential insertion optimization
Summary: The original optimization missed updating links other than the lowest level.

Test Plan: make check; perf_context_test

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, adsharma

Differential Revision: https://reviews.facebook.net/D13119
2013-09-26 15:17:03 -07:00
Haobo Xu
e0aa19a94e [RocbsDB] Add an option to enable set based memtable for perf_context_test
Summary:
as title.
Some result:

-- Sequential insertion of 1M key/value with stock skip list (all in on memtable)
time ./perf_context_test  --total_keys=1000000  --use_set_based_memetable=0
Inserting 1000000 key/value pairs
...
Put uesr key comparison:
Count: 1000000  Average: 8.0179  StdDev: 176.34
Min: 0.0000  Median: 2.5555  Max: 88933.0000
Percentiles: P50: 2.56 P75: 2.83 P99: 58.21 P99.9: 133.62 P99.99: 987.50
Get uesr key comparison:
Count: 1000000  Average: 43.4465  StdDev: 379.03
Min: 2.0000  Median: 36.0195  Max: 88939.0000
Percentiles: P50: 36.02 P75: 43.66 P99: 112.98 P99.9: 824.84 P99.99: 7615.38
real	0m21.345s
user	0m14.723s
sys	0m5.677s

-- Sequential insertion of 1M key/value with set based memtable (all in on memtable)
time ./perf_context_test  --total_keys=1000000  --use_set_based_memetable=1
Inserting 1000000 key/value pairs
...
Put uesr key comparison:
Count: 1000000  Average: 61.5022  StdDev: 6.49
Min: 0.0000  Median: 62.4295  Max: 71.0000
Percentiles: P50: 62.43 P75: 66.61 P99: 71.00 P99.9: 71.00 P99.99: 71.00
Get uesr key comparison:
Count: 1000000  Average: 29.3810  StdDev: 3.20
Min: 1.0000  Median: 29.1801  Max: 34.0000
Percentiles: P50: 29.18 P75: 32.06 P99: 34.00 P99.9: 34.00 P99.99: 34.00
real	0m28.875s
user	0m21.699s
sys	0m5.749s

Worst case comparison for a Put is 88933 (skiplist) vs 71 (set based memetable)

Of course, there's other in-efficiency in set based memtable implementation, which lead to the overall worst performance. However, P99 behavior advantage is very very obvious.

Test Plan: ./perf_context_test and viewstate shadow testing

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13095
2013-09-25 22:49:18 -07:00
Dhruba Borthakur
f1a60e5c3e The vector rep implementation was segfaulting because of incorrect initialization of vector.
Summary:
The constructor for Vector memtable has a parameter called 'count'
that specifies the capacity of the vector to be reserved at allocation
time. It was incorrectly used to initialize the size of the vector.

Test Plan: Enhanced db_test.

Reviewers: haobo, xjin, emayanke

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13083
2013-09-25 11:33:52 -07:00
Dhruba Borthakur
5e9f3a9aa7 Better locking in vectorrep that increases throughput to match speed of storage.
Summary:
There is a use-case where we want to insert data into rocksdb as
fast as possible. Vector rep is used for this purpose.

The background flush thread needs to flush the vectorrep to
storage. It acquires the dblock then sorts the vector, releases
the dblock and then writes the sorted vector to storage. This is
suboptimal because the lock is held during the sort, which
prevents new writes for occuring.

This patch moves the sorting of the vector rep to outside the
db mutex. Performance is now as fastas the underlying storage
system. If you are doing buffered writes to rocksdb files, then
you can observe throughput upwards of 200 MB/sec writes.

This is an early draft and not yet ready to be reviewed.

Test Plan:
make check

Task ID: #

Blame Rev:

Reviewers: haobo

Reviewed By: haobo

CC: leveldb, haobo

Differential Revision: https://reviews.facebook.net/D12987
2013-09-19 21:48:10 -07:00
Haobo Xu
4734dbb742 [RocksDB] Unit test to show Seek key comparison number
Summary: Added SeekKeyComparison to show the uer key comparison incurred by Seek.

Test Plan:
make perf_context_test
export LEVELDB_TESTS=DBTest.SeekKeyComparison
./perf_context_test --write_buffer_size=500000 --total_keys=10000
./perf_context_test --write_buffer_size=250000 --total_keys=10000

Reviewers: dhruba, xjin

Reviewed By: xjin

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12843
2013-09-18 21:43:41 -07:00
Haobo Xu
72fcbf055d [RocksDB] Fix DBTest.UniversalCompactionSizeAmplification too
Summary: as title

Test Plan: make db_test; ./db_test

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13005
2013-09-17 21:29:33 -07:00
Haobo Xu
5b76338c01 [RocksDB] Fix DBTest.UniversalCompactionTrigger to reflect the correct compaction trigger condition.
Summary: as title

Test Plan: make db_test; ./db_test

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12981
2013-09-17 14:17:48 -07:00
Rajat Goel
11c65021fb Revert "Minor fixes found while trying to compile it using clang on Mac OS X"
This reverts commit 5f2c136c32.
2013-09-15 23:01:26 -07:00
Haobo Xu
1d8c57db23 [RocksDB] Universal compaction trigger condition minor fix
Summary: Currently, when total number of files reaches level0_file_num_compaction_trigger, universal compaction will schedule a compaction job, but the job will not honor the compaction until the total number of files is level0_file_num_compaction_trigger+1. Fixed the condition for consistent behavior (start compaction on reaching level0_file_num_compaction_trigger).

Test Plan: make check; db_stress

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12945
2013-09-15 22:35:59 -07:00
Rajat Goel
5f2c136c32 Minor fixes found while trying to compile it using clang on Mac OS X 2013-09-15 22:06:14 -07:00
Dhruba Borthakur
4012ca1c7b Added a parameter to limit the maximum space amplification for universal compaction.
Summary:
Added a new field called max_size_amplification_ratio in the
CompactionOptionsUniversal structure. This determines the maximum
percentage overhead of space amplification.

The size amplification is defined to be the ratio between the size of
the oldest file to the sum of the sizes of all other files. If the
size amplification exceeds the specified value, then min_merge_width
and max_merge_width are ignored and a full compaction of all files is done.
A value of 10 means that the size a database that stores 100 bytes
of user data could occupy 110 bytes of physical storage.

Test Plan: Unit test DBTest.UniversalCompactionSpaceAmplification added.

Reviewers: haobo, emayanke, xjin

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12825
2013-09-13 16:27:18 -07:00
Haobo Xu
0e422308aa [RocksDB] Remove Log file immediately after memtable flush
Summary: As title. The DB log file life cycle is tied up with the memtable it backs. Once the memtable is flushed to sst and committed, we should be able to delete the log file, without holding the mutex. This is part of the bigger change to avoid FindObsoleteFiles at runtime. It deals with log files. sst files will be dealt with later.

Test Plan: make check; db_bench

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11709
2013-09-12 11:54:44 -07:00
Haobo Xu
f2f4c8072f [RocksDB] Added nano second stopwatch and new perf counters to track block read cost
Summary: The pupose of this diff is to expose per user-call level precise timing of block read, so that we can answer questions like: a Get() costs me 100ms, is that somehow related to loading blocks from file system, or sth else? We will answer that with EXACTLY how many blocks have been read, how much time was spent on transfering the bytes from os, how much time was spent on checksum verification and how much time was spent on block decompression, just for that one Get. A nano second stopwatch was introduced to track time with higher precision. The cost/precision of the stopwatch is also measured in unit-test. On my dev box, retrieving one time instance costs about 30ns, on average. The deviation of timing results is good enough to track 100ns-1us level events. And the overhead could be safely ignored for 100us level events (10000 instances/s), for example, a viewstate thrift call.

Test Plan: perf_context_test, also testing with viewstate shadow traffic.

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, xjin

Differential Revision: https://reviews.facebook.net/D12351
2013-09-07 21:14:54 -07:00
Dhruba Borthakur
32c965d417 Flush was hanging because the configured options specified that more than 1 memtable need to be merged.
Summary:
There is an config option called Options.min_write_buffer_number_to_merge
that specifies the minimum number of write buffers to merge in memory
before flushing to a file in L0. But in the the case when the db is
being closed, we should not be using this config, instead we should
flush whatever write buffers were available at that time.

Test Plan: Unit test attached.

Reviewers: haobo, emayanke

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12717
2013-09-06 16:28:33 -07:00
Dhruba Borthakur
197034e4c3 An iterator may automatically invoke reseeks.
Summary:
An iterator invokes reseek if the number of sequential skips over the
same userkey exceeds a configured number. This makes iter->Next()
faster (bacause of fewer key compares) if a large number of
adjacent internal keys in a table (sst or memtable) have the
same userkey.

Test Plan: Unit test DBTest.IterReseek.

Reviewers: emayanke, haobo, xjin

Reviewed By: xjin

CC: leveldb, xjin

Differential Revision: https://reviews.facebook.net/D11865
2013-09-06 11:50:53 -07:00
Mayank Agarwal
aa5c897d42 Return pathname relative to db dir in LogFile and cleanup AppendSortedWalsOfType
Summary: So that replication can just download from wherever LogFile.Pathname is pointing them.

Test Plan: make all check;./db_repl_stress

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12609
2013-09-04 13:44:43 -07:00
Xing Jin
42c109cc2e New ldb command to convert compaction style
Summary:
Add new command "change_compaction_style" to ldb tool. For
universal->level, it shows "nothing to do". For level->universal, it
compacts all files into a single one and moves the file to level 0.

Also add check for number of files at level 1+ when opening db with
universal compaction style.

Test Plan:
'make all check'. New unit test for internal convertion function. Also manully test various
cmd like:

./ldb change_compaction_style --old_compaction_style=0
--new_compaction_style=1 --db=/tmp/leveldbtest-3088/db_test

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: vamsi, emayanke

Differential Revision: https://reviews.facebook.net/D12603
2013-09-04 13:13:08 -07:00
Mayank Agarwal
c34271a5a5 Fix bug in Counters and record Sequencenumber using only TickerCount
Summary:
The way counters/statistics are implemented in rocksdb demands that enum Tickers and TickerNameMap follow the same order, otherwise statistics exposed from fbcode/rocks get out-of-sync. 2 counters for prefix had violated this order and when I built counters for fbcode/mcrocksdb, statistics for sequence number were appearing out-of-sync.
The other change is to record sequence-number using setTickerCount only and not recordTick. This is because of difference in statistics as understood by rocks/utils which uses ServiceData::statistics function and rocksdb statistics. In rocksdb there is just 1 counter for a countername. But in ServiceData there are 4 independent buckets for every countername-Count, Sum, Average and Rate. SetTickerCount and RecordTick update the same variable in rocksdb but different buckets in ServiceData. Therefore, I had to choose one consistent function from RecordTick or SetTickerCount for sequence number in rocksdb. I chose SetTickerCount because the statistics object in options passed during rocksdb-open is user-dependent and SetTickerCount makes sense there.
There will be a corresponding diff to mcorcksdb in fbcode shortly.

Test Plan: make all check; check ticker value using fprintfs

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12669
2013-09-01 17:59:32 -07:00
Mayank Agarwal
ab5c5c28fe Fix build caused by DeleteFile not tolerating / at the beginning
Summary: db->DeleteFile calls ParseFileName to check name that was returned for sst file. Now, sst filename is returned using TableFileName which uses MakeFileName. This puts a / at the front of the name and ParseFileName doesn't like that. Changed ParseFileName to tolerate /s at the beginning. The test delet_file_test used to pass earlier because this behaviour of MakeFileName had been changed a while back to not return a / during which delete_file_test was checked in. But MakeFileName had to be reverted to add / at the front because GetLiveFiles used at many places outside rocksdb used the previous behaviour of MakeFileName.

Test Plan: make;./delete_filetest;make all check

Reviewers: dhruba, haobo, vamsi

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12663
2013-09-01 17:59:13 -07:00
Mayank Agarwal
46dcf51ca5 Return a '/' before names of all files through MakeFileName
Summary: // won't hurt but a missing / hurts sometimes

Test Plan: make all check; ./db_repl_stress

Reviewers: vamsi

Reviewed By: vamsi

CC: dhruba

Differential Revision: https://reviews.facebook.net/D12621
2013-08-30 14:25:22 -07:00
Dhruba Borthakur
59de2dbad7 Cleanup DeleteFile API
Summary:
The DeleteFile API was removing files inside the db-lock. This
is now changed to remove files outside the db-lock.
The GetLiveFilesMetadata() returns the smallest and largest
seqnuence number of each file as well.

Test Plan: deletefile_test

Reviewers: emayanke, haobo

Reviewed By: haobo

CC: leveldb

Maniphest Tasks: T63

Differential Revision: https://reviews.facebook.net/D12567
2013-08-28 21:18:58 -07:00
Haobo Xu
48e5ea0c34 [RocksDB] Fix TransformRepFactory related valgrind problem
Summary: Let TransformRepFactory own the passed in transform. Also make it better encapsulated.

Test Plan: make valgrind_check;

Reviewers: dhruba, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12591
2013-08-28 19:27:54 -07:00
Dhruba Borthakur
fc0c399d2e Introduced a new flag non_blocking_io in ReadOptions.
Summary:
If ReadOptions.non_blocking_io is set to true, then KeyMayExists
and Iterators will return data that is cached in RAM.
If the Iterator needs to do IO from storage to serve the data,
then the Iterator.status() will return Status::IsRetry().

Test Plan:
Enhanced unit test DBTest.KeyMayExist to detect if there were are IOs
issues from storage. Added DBTest.NonBlockingIteration to verify
nonblocking Iterations.

Reviewers: emayanke, haobo

Reviewed By: haobo

CC: leveldb

Maniphest Tasks: T63

Differential Revision: https://reviews.facebook.net/D12531
2013-08-28 10:49:14 -07:00
Haobo Xu
43eef52001 [RocksDB] move stats counting outside of mutex protected region for DB::Get()
Summary:
As title. This is possible as tickers are atomic now.
db_bench on high qps in-memory muti-thread random get workload, showed ~5% throughput improvement.

Test Plan: make check; db_bench; db_stress

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12555
2013-08-27 13:36:10 -07:00
Mayank Agarwal
dad2731729 Fix bug in KeyMayExist
Summary: In KeyMayExist.db_test we do a Flush which causes sst file to be written and added as open file in TableCache, but block cache for the file is not populated. So value_found should have been false where it was true and KeyMayExist.db_test should not have passed earlier. But it passed because BlockReader in table/table.cc takes 2 default arguments at the end called for_compaction and no_io. Although I passed no_io=true from InternalGet to BlockReader, but it understood for_compaction=true and defaulted no_io to false. This is a bug and although will be removed by Dhruba's new patch to incorporate no_io in readoptions, I'm submitting this patch to fix this bug independently of that patch.

Test Plan: make all check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12537
2013-08-26 08:45:58 -07:00
Mayank Agarwal
b1074ac24f Use initializer list for VersionSet
Summary: initialiszer list is fasteri/preferable because it can straightaway call the constructor for this object, otherwise it will be created first and then again initialized. Although gain may not be much in this case because files_ is just a pointer and not a complex object, this is recommended practice.

Test Plan: make all check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12519
2013-08-24 18:16:01 -07:00
Deon Nicholas
573844807c Fix for no_io
Summary: Oops. My bad.

Test Plan: Make all check

Reviewers: emayanke

Reviewed By: emayanke

CC: haobo, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D12525
2013-08-23 16:36:01 -07:00
Tyler Harter
4504c99030 Internal/user key bug fix.
Summary: Fix code so that the filter_block layer only assumes keys are internal when prefix_extractor is set.

Test Plan: ./filter_block_test

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12501
2013-08-23 14:49:57 -07:00
Dhruba Borthakur
1186192ed1 Replace include/leveldb with include/rocksdb.
Summary: Replace include/leveldb with include/rocksdb.

Test Plan:
make clean; make check
make clean; make release

Differential Revision: https://reviews.facebook.net/D12489
2013-08-23 10:51:00 -07:00
Jim Paton
74781a0c49 Add three new MemTableRep's
Summary:
This patch adds three new MemTableRep's: UnsortedRep, PrefixHashRep, and VectorRep.

UnsortedRep stores keys in an std::unordered_map of std::sets. When an iterator is requested, it dumps the keys into an std::set and iterates over that.

VectorRep stores keys in an std::vector. When an iterator is requested, it creates a copy of the vector and sorts it using std::sort. The iterator accesses that new vector.

PrefixHashRep stores keys in an unordered_map mapping prefixes to ordered sets.

I also added one API change. I added a function MemTableRep::MarkImmutable. This function is called when the rep is added to the immutable list. It doesn't do anything yet, but it seems like that could be useful. In particular, for the vectorrep, it means we could elide the extra copy and just sort in place. The only reason I haven't done that yet is because the use of the ArenaAllocator complicates things (I can elaborate on this if needed).

Test Plan:
make -j32 check
./db_stress --memtablerep=vector
./db_stress --memtablerep=unsorted
./db_stress --memtablerep=prefixhash --prefix_size=10

Reviewers: dhruba, haobo, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12117
2013-08-22 23:10:02 -07:00
Xing Jin
17dc128048 Pull from https://reviews.facebook.net/D10917
Summary: Pull Mark's patch and slightly revise it. I revised another place in db_impl.cc with similar new formula.

Test Plan:
make all check. Also run "time ./db_bench --num=2500000000 --numdistinct=2200000000". It has run for 20+ hours and hasn't finished. Looks good so far:

Installed stack trace handler for SIGILL SIGSEGV SIGBUS SIGABRT
LevelDB:    version 2.0
Date:       Tue Aug 20 23:11:55 2013
CPU:        32 * Intel(R) Xeon(R) CPU E5-2660 0 @ 2.20GHz
CPUCache:   20480 KB
Keys:       16 bytes each
Values:     100 bytes each (50 bytes after compression)
Entries:    2500000000
RawSize:    276565.6 MB (estimated)
FileSize:   157356.3 MB (estimated)
Write rate limit: 0
Compression: snappy
WARNING: Assertions are enabled; benchmarks unnecessarily slow
------------------------------------------------
DB path: [/tmp/leveldbtest-3088/dbbench]
fillseq      :    7202.000 micros/op 138 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
fillsync     :    7148.000 micros/op 139 ops/sec; (2500000 ops)
DB path: [/tmp/leveldbtest-3088/dbbench]
fillrandom   :    7105.000 micros/op 140 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
overwrite    :    6930.000 micros/op 144 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
readrandom   :       1.020 micros/op 980507 ops/sec; (0 of 2500000000 found)
DB path: [/tmp/leveldbtest-3088/dbbench]
readrandom   :       1.021 micros/op 979620 ops/sec; (0 of 2500000000 found)
DB path: [/tmp/leveldbtest-3088/dbbench]
readseq      :     113.000 micros/op 8849 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
readreverse  :     102.000 micros/op 9803 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
Created bg thread 0x7f0ac17f7700
compact      :  111701.000 micros/op 8 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
readrandom   :       1.020 micros/op 980376 ops/sec; (0 of 2500000000 found)
DB path: [/tmp/leveldbtest-3088/dbbench]
readseq      :     120.000 micros/op 8333 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
readreverse  :      29.000 micros/op 34482 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
... finished 618100000 ops

Reviewers: MarkCallaghan, haobo, dhruba, chip

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D12441
2013-08-22 22:37:13 -07:00
Tyler Harter
94cf218720 Revert "Prefix scan: db_bench and bug fixes"
This reverts commit c2bd8f4824.
2013-08-22 18:01:11 -07:00
Tyler Harter
c2bd8f4824 Prefix scan: db_bench and bug fixes
Summary: If use_prefix_filters is set and read_range>1, then the random seeks will set a the prefix filter to be the prefix of the key which was randomly selected as the target.  Still need to add statistics (perhaps in a separate diff).

Test Plan: ./db_bench --benchmarks=fillseq,prefixscanrandom --num=10000000 --statistics=1 --use_prefix_blooms=1 --use_prefix_api=1 --bloom_bits=10

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, haobo

Differential Revision: https://reviews.facebook.net/D12273
2013-08-22 16:06:50 -07:00
Simha Venkataramaiah
60bf2b7d4a Add APIs to query SST file metadata and to delete specific SST files
Summary: An api to query the level, key ranges, size etc for each SST file and an api to delete a specific file from the db and all associated state in the bookkeeping datastructures.

Notes: Editing the manifest version does not release the obsolete files right away. However deleting the file directly will mess up the iterator. We may need a more aggressive/timely file deletion api.

I have used std::unique_ptr - will switch to boost:: since this is external. thoughts?

Unit test is fragile right now as it expects the compaction at certain levels.

Test Plan: unittest

Reviewers: dhruba, vamsi, emayanke

CC: zshao, leveldb, haobo

Task ID: #

Blame Rev:
2013-08-22 15:27:19 -07:00
Jim Paton
cb703c9d03 Allow WriteBatch::Handler to abort iteration
Summary:
Sometimes you don't need to iterate through the whole WriteBatch. This diff makes the Handler member functions return a bool that indicates whether to abort or not. If they return true, the iteration stops.

One thing I just thought of is that this will break backwards-compability. Maybe it would be better to add a virtual member function WriteBatch::Handler::ShouldAbort() that returns false by default. Comments requested.

I still have to add a new unit test for the abort code, but let's finalize the API first.

Test Plan: make -j32 check

Reviewers: dhruba, haobo, vamsi, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12339
2013-08-21 18:27:48 -07:00
Haobo Xu
f9e2decf7c [RocksDB] Minor iterator cleanup
Summary: Was going through the iterator related code, did some cleanup along the way. Basically replaced array with vector and adopted range based loop where applicable.

Test Plan: make check; make valgrind_check

Reviewers: dhruba, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12435
2013-08-21 16:54:48 -07:00
Deon Nicholas
b87dcae1a3 Made merge_oprator a shared_ptr; and added TTL unit tests
Test Plan:
- make all check;
- make release;
- make stringappend_test; ./stringappend_test

Reviewers: haobo, emayanke

Reviewed By: haobo

CC: leveldb, kailiu

Differential Revision: https://reviews.facebook.net/D12381
2013-08-20 13:35:28 -07:00
Mayank Agarwal
8a3547d38e API for getting archived log files
Summary: Also expanded class LogFile to have startSequene and FileSize and exposed it publicly

Test Plan: make all check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12087
2013-08-19 13:37:04 -07:00
Deon Nicholas
e1346968d8 Merge operator fixes part 1.
Summary:
-Added null checks and revisions to DBIter::MergeValuesNewToOld()
-Added DBIter test to stringappend_test
-Major fix with Merge and TTL
More plans for fixes later.

Test Plan:
-make clean; make stringappend_test -j 32; ./stringappend_test
-make all check;

Reviewers: haobo, emayanke, vamsi, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12315
2013-08-19 11:42:47 -07:00
Mayank Agarwal
387ac0f1e1 Expose statistic for sequence number and implement setTickerCount
Summary: statistic for sequence number is needed by wormhole. setTickerCount is demanded for this statistic. I can't simply recordTick(max_sequence) when db recovers because the statistic iobject is owned by client and may/may not be reset during reopen. Eg. statistic is reset in mcrocksdb whereas it is not in db_stress. Therefore it is best to go with setTickerCount

Test Plan: ./db_stress ... --statistics=1 and observed expected sequence number

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12327
2013-08-15 23:00:20 -07:00
Deon Nicholas
d1d3d15eb7 Tiny fix to db_bench for make release.
Summary:
In release, "found variable assigned but not used anywhere". Changed it to work with
assert. Someone accept this :).

Test Plan: make release -j 32

Reviewers: haobo, dhruba, emayanke

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12309
2013-08-15 17:50:12 -07:00
Deon Nicholas
ad48c3c262 Benchmarking for Merge Operator
Summary:
Updated db_bench and utilities/merge_operators.h to allow for dynamic benchmarking
of merge operators in db_bench. Added a new test (--benchmarks=mergerandom), which performs
a bunch of random Merge() operations over random keys. Also added a "--merge_operator=" flag
so that the tester can easily benchmark different merge operators. Currently supports
the PutOperator and UInt64Add operator. Support for stringappend or list append may come later.

Test Plan:
	1. make db_bench
	2. Test the PutOperator (simulating Put) as follows:
./db_bench --benchmarks=fillrandom,readrandom,updaterandom,readrandom,mergerandom,readrandom --merge_operator=put
--threads=2

3. Test the UInt64AddOperator (simulating numeric addition) similarly:
./db_bench --value_size=8 --benchmarks=fillrandom,readrandom,updaterandom,readrandom,mergerandom,readrandom
--merge_operator=uint64add --threads=2

Reviewers: haobo, dhruba, zshao, MarkCallaghan

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11535
2013-08-15 17:13:07 -07:00
Xing Jin
0a5afd1afc Minor fix to current codes
Summary:
Minor fix to current codes, including: coding style, output format,
comments. No major logic change. There are only 2 real changes, please see my inline comments.

Test Plan: make all check

Reviewers: haobo, dhruba, emayanke

Differential Revision: https://reviews.facebook.net/D12297
2013-08-14 23:03:57 -07:00
Jim Paton
0307c5fe3a Implement log blobs
Summary:
This patch adds the ability for the user to add sequences of arbitrary data (blobs) to write batches. These blobs are saved to the log along with everything else in the write batch. You can add multiple blobs per WriteBatch and the ordering of blobs, puts, merges, and deletes are preserved.

Blobs are not saves to SST files. RocksDB ignores blobs in every way except for writing them to the log.

Before committing this patch, I need to add some test code. But I'm submitting it now so people can comment on the API.

Test Plan: make -j32 check

Reviewers: dhruba, haobo, vamsi

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12195
2013-08-14 16:32:46 -07:00
Haobo Xu
d9dd2a1926 [RocksDB] Expose thread local perf counter for low overhead, per call level performance statistics.
Summary:
As title. No locking/atomic is needed due to thread local. There is also no need to modify the existing client interface, in order to expose related counters.

perf_context_test shows a simple example of retrieving the number of user key comparison done for each put and get call. More counters could be added later.

Sample output
./perf_context_test 1000000
==== Test PerfContextTest.KeyComparisonCount
Inserting 1000000 key/value pairs
...
total user key comparison get: 43446523
total user key comparison put: 8017877
max user key comparison get: 88939
avg user key comparison get:43

Basically, the current skiplist does well on average, but could perform poorly in extreme cases.

Test Plan: run perf_context_test <total number of entries to put/get>

Reviewers: dhruba

Differential Revision: https://reviews.facebook.net/D12225
2013-08-14 15:24:06 -07:00
Mayank Agarwal
f1bf169484 Counter for merge failure
Summary:
With Merge returning bool, it can keep failing silently(eg. While faling to fetch timestamp in TTL). We need to detect this through a rocksdb counter which can get bumped whenever Merge returns false. This will also be super-useful for the mcrocksdb-counter service where Merge may fail.
Added a counter NUMBER_MERGE_FAILURES and appropriately updated db/merge_helper.cc

I felt that it would be better to directly add counter-bumping in Merge as a default function of MergeOperator class but user should not be aware of this, so this approach seems better to me.

Test Plan: make all check

Reviewers: dnicholas, haobo, dhruba, vamsi

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12129
2013-08-13 14:25:42 -07:00
Tyler Harter
f5f1842282 Prefix filters for scans (v4)
Summary: Similar to v2 (db and table code understands prefixes), but use ReadOptions as in v3.  Also, make the CreateFilter code faster and cleaner.

Test Plan: make db_test; export LEVELDB_TESTS=PrefixScan; ./db_test

Reviewers: dhruba

Reviewed By: dhruba

CC: haobo, emayanke

Differential Revision: https://reviews.facebook.net/D12027
2013-08-13 14:04:56 -07:00
sumeet
3b81df34bd Separate compaction filter for each compaction
Summary:
If we have same compaction filter for each compaction,
application cannot know about the different compaction processes.
Later on, we can put in more details in compaction filter for the
application to consume and use it according to its needs. For e.g. In
the universal compaction, we have a compaction process involving all the
files while others don't involve all the files. Applications may want to
collect some stats only when during full compaction.

Test Plan: run existing unit tests

Reviewers: haobo, dhruba

Reviewed By: dhruba

CC: xinyaohu, leveldb

Differential Revision: https://reviews.facebook.net/D12057
2013-08-13 10:56:20 -07:00
Dhruba Borthakur
03bd4461ad Merge branch 'performance' of github.com:facebook/rocksdb into performance 2013-08-12 10:31:21 -07:00
Dhruba Borthakur
f3967a5132 Merge remote-tracking branch 'origin' into performance 2013-08-12 09:58:50 -07:00
Dhruba Borthakur
93d77a27d2 Universal Compaction should keep DeleteMarkers unless it is the earliest file.
Summary:
The pre-existing code was purging a DeleteMarker if thay key did not
exist in deeper levels.  But in the Universal Compaction Style, all
files are in Level0. For compaction runs that did not include the
earliest file, we were erroneously purging the DeleteMarkers.

The fix is to purge DeleteMarkers only if the compaction includes
the earlist file.

Test Plan: DBTest.Randomized triggers this code path.

Differential Revision: https://reviews.facebook.net/D12081
2013-08-09 14:03:57 -07:00
Xing Jin
8ae905ed63 Fix unit tests for universal compaction (step 2)
Summary:
Continue fixing existing unit tests for universal compaction. I have
tried to apply universal compaction to all unit tests those haven't
called ChangeOptions(). I left a few which are either apparently not
applicable to universal compaction (because they check files/keys/values
at level 1 or above levels), or apparently not related to compaction
(e.g., open a file, open a db).

I also add a new unit test for universal compaction.

Good news is I didn't see any bugs during this round.

Test Plan: Ran "make all check" yesterday. Has rebased and is rerunning

Reviewers: haobo, dhruba

Differential Revision: https://reviews.facebook.net/D12135
2013-08-09 13:35:44 -07:00
Haobo Xu
3a3b1c3e6c [RocksDB] Improve manifest dump to print internal keys in hex for version edits.
Summary: Currently, VersionEdit::DebugString always display internal keys in the original ascii format. This could cause manifest dump to be truncated if internal keys contain special charactors (like null). Also added an option --input_key_hex for ldb idump to indicate that the passed in user keys are in hex.

Test Plan: run ldb manifest_dump

Reviewers: dhruba, emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12111
2013-08-08 16:19:01 -07:00
Xing Jin
17b8f786a3 Fix unit tests/bugs for universal compaction (first step)
Summary:
This is the first step to fix unit tests and bugs for universal
compactiion. I added universal compaction option to ChangeOptions(), and
fixed all unit tests calling ChangeOptions(). Some of these tests
obviously assume more than 1 level and check file number/values in level
1 or above levels. I set kSkipUniversalCompaction for these tests.

The major bug I found is manual compaction with universal compaction never stops. I have put a fix for
it.

I have also set universal compaction as the default compaction and found
at least 20+ unit tests failing. I haven't looked into the details. The
next step is to check all unit tests without calling ChangeOptions().

Test Plan: make all check

Reviewers: dhruba, haobo

Differential Revision: https://reviews.facebook.net/D12051
2013-08-07 14:05:44 -07:00
Dhruba Borthakur
f5fa26b6a9 Merge branch 'performance' of github.com:facebook/rocksdb into performance
Conflicts:
	db/builder.cc
	db/db_impl.cc
	db/version_set.cc
	include/leveldb/statistics.h
2013-08-07 11:58:06 -07:00
Deon Nicholas
68a4cdf3f7 Build fix with merge_test and ttl 2013-08-06 11:42:21 -07:00
Deon Nicholas
c2d7826ced [RocksDB] [MergeOperator] The new Merge Interface! Uses merge sequences.
Summary:
Here are the major changes to the Merge Interface. It has been expanded
to handle cases where the MergeOperator is not associative. It does so by stacking
up merge operations while scanning through the key history (i.e.: during Get() or
Compaction), until a valid Put/Delete/end-of-history is encountered; it then
applies all of the merge operations in the correct sequence starting with the
base/sentinel value.

I have also introduced an "AssociativeMerge" function which allows the user to
take advantage of associative merge operations (such as in the case of counters).
The implementation will always attempt to merge the operations/operands themselves
together when they are encountered, and will resort to the "stacking" method if
and only if the "associative-merge" fails.

This implementation is conjectured to allow MergeOperator to handle the general
case, while still providing the user with the ability to take advantage of certain
efficiencies in their own merge-operator / data-structure.

NOTE: This is a preliminary diff. This must still go through a lot of review,
revision, and testing. Feedback welcome!

Test Plan:
  -This is a preliminary diff. I have only just begun testing/debugging it.
  -I will be testing this with the existing MergeOperator use-cases and unit-tests
(counters, string-append, and redis-lists)
  -I will be "desk-checking" and walking through the code with the help gdb.
  -I will find a way of stress-testing the new interface / implementation using
db_bench, db_test, merge_test, and/or db_stress.
  -I will ensure that my tests cover all cases: Get-Memtable,
Get-Immutable-Memtable, Get-from-Disk, Iterator-Range-Scan, Flush-Memtable-to-L0,
Compaction-L0-L1, Compaction-Ln-L(n+1), Put/Delete found, Put/Delete not-found,
end-of-history, end-of-file, etc.
  -A lot of feedback from the reviewers.

Reviewers: haobo, dhruba, zshao, emayanke

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11499
2013-08-05 20:14:32 -07:00
Jim Paton
8e792e5896 Add soft_rate_limit stats
Summary: This diff adds histogram stats for soft_rate_limit stalls. It also renames the old rate_limit stats to hard_rate_limit.

Test Plan: make -j32 check

Reviewers: dhruba, haobo, MarkCallaghan

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12021
2013-08-05 18:45:23 -07:00
Mayank Agarwal
1d7b4765c3 Expose base db object from ttl wrapper
Summary: rocksdb replicaiton will need this when writing value+TS from master to slave 'as is'

Test Plan: make

Reviewers: dhruba, vamsi, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11919
2013-08-05 18:44:14 -07:00
Jim Paton
1036537c94 Add soft and hard rate limit support
Summary:
This diff adds support for both soft and hard rate limiting. The following changes are included:

1) Options.rate_limit is renamed to Options.hard_rate_limit.
2) Options.rate_limit_delay_milliseconds is renamed to Options.rate_limit_delay_max_milliseconds.
3) Options.soft_rate_limit is added.
4) If the maximum compaction score is > hard_rate_limit and rate_limit_delay_max_milliseconds == 0, then writes are delayed by 1 ms at a time until the max compaction score falls below hard_rate_limit.
5) If the max compaction score is > soft_rate_limit but <= hard_rate_limit, then writes are delayed by 0-1 ms depending on how close we are to hard_rate_limit.
6) Users can disable 4 by setting hard_rate_limit = 0. They can add a limit to the maximum amount of time waited by setting rate_limit_delay_max_milliseconds > 0. Thus, the old behavior can be preserved by setting soft_rate_limit = 0, which is the default.

Test Plan:
make -j32 check
./db_stress

Reviewers: dhruba, haobo, MarkCallaghan

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12003
2013-08-05 15:43:49 -07:00
Dhruba Borthakur
711a30cb30 Merge branch 'master' into performance
Conflicts:
	include/leveldb/options.h
	include/leveldb/statistics.h
	util/options.cc
2013-08-02 10:22:08 -07:00
Mayank Agarwal
c42485f67c Merge operator for ttl
Summary: Implemented a TtlMergeOperator class which inherits from MergeOperator and is TTL aware. It strips out timestamp from existing_value and attaches timestamp to new_value, calling user-provided-Merge in between.

Test Plan: make all check

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11775
2013-08-01 09:27:17 -07:00
Mayank Agarwal
59d0b02f8b Expand KeyMayExist to return the proper value if it can be found in memory and also check block_cache
Summary: Removed KeyMayExistImpl because KeyMayExist demanded Get like semantics now. Removed no_io from memtable and imm because we need the proper value now and shouldn't just stop when we see Merge in memtable. Added checks to block_cache. Updated documentation and unit-test

Test Plan: make all check;db_stress for 1 hour

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11853
2013-08-01 09:07:46 -07:00
Jim Paton
9700677a2b Slow down writes gradually rather than suddenly
Summary:
Currently, when a certain number of level0 files (level0_slowdown_writes_trigger) are present, RocksDB will slow down each write by 1ms. There is a second limit of level0 files at which RocksDB will stop writes altogether (level0_stop_writes_trigger).

This patch enables the user to supply a third parameter specifying the number of files at which Rocks will start slowing down writes (level0_start_slowdown_writes). When this number is reached, Rocks will slow down writes as a quadratic function of level0_slowdown_writes_trigger - num_level0_files.

For some workloads, this improves latency and throughput. I will post some stats momentarily in https://our.intern.facebook.com/intern/tasks/?t=2613384.

Test Plan:
make -j32 check
./db_stress
./db_bench

Reviewers: dhruba, haobo, MarkCallaghan, xjin

Reviewed By: xjin

CC: leveldb, xjin, zshao

Differential Revision: https://reviews.facebook.net/D11859
2013-07-31 16:20:48 -07:00
Xing Jin
0f0a24e298 Make arena block size configurable
Summary:
Add an option for arena block size, default value 4096 bytes. Arena will allocate blocks with such size.

I am not sure about passing parameter to skiplist in the new virtualized framework, though I talked to Jim a bit. So add Jim as reviewer.

Test Plan:
new unit test, I am running db_test.

For passing paramter from configured option to Arena, I tried tests like:

  TEST(DBTest, Arena_Option) {
  std::string dbname = test::TmpDir() + "/db_arena_option_test";
  DestroyDB(dbname, Options());

  DB* db = nullptr;
  Options opts;
  opts.create_if_missing = true;
  opts.arena_block_size = 1000000; // tested 99, 999999
  Status s = DB::Open(opts, dbname, &db);
  db->Put(WriteOptions(), "a", "123");
  }

and printed some debug info. The results look good. Any suggestion for such a unit-test?

Reviewers: haobo, dhruba, emayanke, jpaton

Reviewed By: dhruba

CC: leveldb, zshao

Differential Revision: https://reviews.facebook.net/D11799
2013-07-31 12:42:23 -07:00
Jim Paton
6db52b525a Don't use redundant Env::NowMicros() calls
Summary: After my patch for stall histograms, there are redundant calls to NowMicros() by both the stop watches and DBImpl::MakeRoomForWrites. So I removed the redundant calls such that the information is gotten from the stopwatch.

Test Plan:
make clean
make -j32 check

Reviewers: dhruba, haobo, MarkCallaghan

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11883
2013-07-29 15:46:36 -07:00
Jim Paton
abc90b067c Use specific DB name in merge_test
Summary: Currently, merge_test uses /tmp/testdb for the test database. It should really use something more specific to merge_test. Most of the other tests use test::TmpDir() + "/<test name>db". This patch implements such behavior for merge_test; it makes merge_test use test::TmpDir() + "/merge_testdb"

Test Plan:
make clean
make -j32 merge_test
./merge_test

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11877
2013-07-29 13:26:38 -07:00
Jim Paton
18afff2e63 Add stall counts to statistics
Summary: Previously, statistics are kept on how much time is spent on stalls of different types. This patch adds support for keeping number of stalls of each type. For example, instead of just reporting how many microseconds are spent waiting for memtables to be compacted, it will also report how many times a write stalled for that to occur.

Test Plan:
make -j32 check
./db_stress

# Not really sure what else should be done...

Reviewers: dhruba, MarkCallaghan, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11841
2013-07-29 10:34:23 -07:00
Dhruba Borthakur
a91fdf1b99 The target file size for L0 files was incorrectly set to LLONG_MAX.
Summary:
The target file size should be valid value. Only if UniversalCompactionStyle
is enabled then set max file size to be LLONG_MAX.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-07-24 14:28:00 -07:00
Dhruba Borthakur
d7ba5bce37 Revert 6fbe4e981a: If disable wal is set, then batch commits are avoided
Summary:
Revert "If disable wal is set, then batch commits are avoided" because
keeping the mutex while inserting into the skiplist means that readers
and writes are all serialized on the mutex.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-07-24 10:01:13 -07:00
Jim Paton
52d7ecfc78 Virtualize SkipList Interface
Summary: This diff virtualizes the skiplist interface so that users can provide their own implementation of a backing store for MemTables. Eventually, the backing store will be responsible for its own synchronization, allowing users (and us) to experiment with different lockless implementations.

Test Plan:
make clean
make -j32 check
./db_stress

Reviewers: dhruba, emayanke, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11739
2013-07-23 14:42:27 -07:00
Dhruba Borthakur
6fbe4e981a If disable wal is set, then batch commits are avoided.
Summary:
rocksdb uses batch commit to write to transaction log. But if
disable wal is set, then writes to transaction log are anyways
avoided. In this case, there is not much value-add to batch things,
batching can cause unnecessary delays to Puts().
This patch avoids batching when disableWal is set.

Test Plan:
make check.

I am running db_stress now.

Reviewers: haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11763
2013-07-23 14:22:57 -07:00
Mayank Agarwal
bf66c10b13 Use KeyMayExist for WriteBatch-Deletes
Summary:
Introduced KeyMayExist checking during writebatch-delete and removed from Outer Delete API because it uses writebatch-delete.
Added code to skip getting Table from disk if not already present in table_cache.
Some renaming of variables.
Introduced KeyMayExistImpl which allows checking since specified sequence number in GetImpl useful to check partially written writebatch.
Changed KeyMayExist to not be pure virtual and provided a default implementation.
Expanded unit-tests in db_test to check appropriately.
Ran db_stress for 1 hour with ./db_stress --max_key=100000 --ops_per_thread=10000000 --delpercent=50 --filter_deletes=1 --statistics=1.

Test Plan: db_stress;make check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb, xjin

Differential Revision: https://reviews.facebook.net/D11745
2013-07-23 13:36:50 -07:00
Haobo Xu
d364eea1fc [RocksDB] Fix FindMinimumEmptyLevelFitting
Summary: as title

Test Plan: make check;

Reviewers: xjin

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11751
2013-07-22 12:31:43 -07:00
Haobo Xu
9ee68871dc [RocksDB] Enable manual compaction to move files back to an appropriate level.
Summary: As title. This diff added an option reduce_level to CompactRange. When set to true, it will try to move the files back to the minimum level sufficient to hold the data set. Note that the default is set to true now, just to excerise it in all existing tests. Will set the default to false before check-in, for backward compatibility.

Test Plan: make check;

Reviewers: dhruba, emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11553
2013-07-19 16:20:36 -07:00
Dhruba Borthakur
4a745a5666 Merge branch 'master' into performance
Conflicts:
	db/version_set.cc
	include/leveldb/options.h
	util/options.cc
2013-07-17 15:05:57 -07:00
Dhruba Borthakur
76a4923307 Make file-sizes and grandparentoverlap to be unsigned to avoid bad comparisions.
Summary:
The maxGrandParentOverlapBytes_ was signed which was causing
an erroneous comparision between signed and unsigned longs.
This, in turn, was causing compaction-created-output-files
to be very small in size.

Test Plan: make check

Differential Revision: https://reviews.facebook.net/D11727
2013-07-17 14:26:06 -07:00
Mayank Agarwal
e9b675bd94 Fix memory leak in KeyMayExist test part of db_test
Summary: NewBloomFilterPolicy call requires Delete to be called later on

Test Plan: make; valgrind ./db_test

Reviewers: haobo, dhruba, vamsi

Differential Revision: https://reviews.facebook.net/D11667
2013-07-12 16:58:57 -07:00
Mayank Agarwal
2a986919d6 Make rocksdb-deletes faster using bloom filter
Summary:
Wrote a new function in db_impl.c-CheckKeyMayExist that calls Get but with a new parameter turned on which makes Get return false only if bloom filters can guarantee that key is not in database. Delete calls this function and if the option- deletes_use_filter is turned on and CheckKeyMayExist returns false, the delete will be dropped saving:
1. Put of delete type
2. Space in the db,and
3. Compaction time

Test Plan:
make all check;
will run db_stress and db_bench and enhance unit-test once the basic design gets approved

Reviewers: dhruba, haobo, vamsi

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11607
2013-07-11 12:11:11 -07:00
Xing Jin
8a5341ec7d Newbie code question
Summary:
This diff is more about my question when reading compaction codes,
instead of a normal diff. I don't quite understand the logic here.

Test Plan: I didn't do any test. If this is a bug, I will continue doing some test.

Reviewers: haobo, dhruba, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11661
2013-07-11 09:03:40 -07:00
Dhruba Borthakur
289efe9922 Update statistics only if needed.
Summary:
Update statistics only if needed.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-07-09 16:17:00 -07:00
Dhruba Borthakur
7cb8d462d5 Rename PickCompactionHybrid to PickCompactionUniversal.
Summary:
Rename PickCompactionHybrid to PickCompactionUniversal.
Changed a few LOG message from "Hybrid:" to "Universal:".

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-07-09 16:08:54 -07:00
Haobo Xu
a8d5f8dde2 [RocksDB] Remove old readahead options
Summary: As title.

Test Plan: make check; db_bench

Reviewers: dhruba, MarkCallaghan

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11643
2013-07-09 11:22:33 -07:00
Haobo Xu
9ba82786ce [RocksDB] Provide contiguous sequence number even in case of write failure
Summary: Replication logic would be simplifeid if we can guarantee that write sequence number is always contiguous, even if write failure occurs. Dhruba and I looked at the sequence number generation part of the code. It seems fixable. Note that if WAL was successful and insert into memtable was not, we would be in an unfortunate state. The approach in this diff is : IO error is expected and error status will be returned to client, sequence number will not be advanced; In-mem error is not expected and we panic.

Test Plan: make check; db_stress

Reviewers: dhruba, sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11439
2013-07-08 15:31:09 -07:00
Dhruba Borthakur
116ec527f2 Renamed 'hybrid_compaction' tp be "Universal Compaction'.
Summary:
All the universal compaction parameters are encapsulated in
a new file universal_compaction.h

Test Plan:
make check
2013-07-03 15:47:53 -07:00
Dhruba Borthakur
47c4191fe8 Reduce write amplification by merging files in L0 back into L0
Summary:
There is a new option called hybrid_mode which, when switched on,
causes HBase style compactions.  Files from L0 are
compacted back into L0. This meat of this compaction algorithm
is in PickCompactionHybrid().

All files reside in L0. That means all files have overlapping
keys. Each file has a time-bound, i.e. each file contains a
range of keys that were inserted around the same time. The
start-seqno and the end-seqno refers to the timeframe when
these keys were inserted.  Files that have contiguous seqno
are compacted together into a larger file. All files are
ordered from most recent to the oldest.

The current compaction algorithm starts to look for
candidate files starting from the most recent file. It continues to
add more files to the same compaction run as long as the
sum of the files chosen till now is smaller than the next
candidate file size. This logic needs to be debated
and validated.

The above logic should reduce write amplification to a
large extent... will publish numbers shortly.

Test Plan: dbstress runs for 6 hours with no data corruption (tested so far).

Differential Revision: https://reviews.facebook.net/D11289
2013-06-30 20:07:04 -07:00
Haobo Xu
71e0f695c1 [RocksDB] Expose count for WriteBatch
Summary: As title. Exposed a Count function that returns the number of updates in a batch. Could be handy for replication sequence number check.

Test Plan: make check;

Reviewers: emayanke, sheki, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11523
2013-06-26 15:13:21 -07:00
Abhishek Kona
5ef6bb8c37 [rocksdb][refactor] statistic printing code to one place
Summary: $title

Test Plan: db_bench --statistics=1

Reviewers: haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11373
2013-06-18 20:28:41 -07:00
Haobo Xu
3cc1af2062 [RocksDB] Option for incremental sync
Summary: This diff added an option to control the incremenal sync frequency. db_bench has a new flag bytes_per_sync for easy tuning exercise.

Test Plan: make check; db_bench

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11295
2013-06-18 15:00:32 -07:00
Abhishek Kona
79f4fd2b62 [Rocksdb] Simplify Printing code in db_bench
Summary:
simplify the printing code in db_bench
         use TickersMap and HistogramsNameMap introduced in previous diffs.

Test Plan: ./db_bench --statistics=1 and see if all the statistics are printed

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11355
2013-06-18 14:58:00 -07:00
Dhruba Borthakur
6acbe0fc45 Compact multiple memtables before flushing to storage.
Summary:
Merge multiple multiple memtables in memory before writing it
out to a file in L0.

There is a new config parameter min_write_buffer_number_to_merge
that specifies the number of write buffers that should be merged
together to a single file in storage. The system will not flush
wrte buffers to storage unless at least these many buffers have
accumulated in memory.
The default value of this new parameter is 1, which means that
a write buffer will be immediately flushed to disk as soon it is
ready.

Test Plan: make check

Differential Revision: https://reviews.facebook.net/D11241
2013-06-18 14:28:04 -07:00
Abhishek Kona
00124683de [rocksdb] do not trim range for level0 in manual compaction
Summary:
https://code.google.com/p/leveldb/issues/detail?can=1&q=178&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary&id=178

Ported the solution as is to RocksDB.

Test Plan: moved the unit test as manual_compaction_test

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11331
2013-06-17 13:58:17 -07:00
Abhishek Kona
bff718d81c [Rocksdb] Implement filluniquerandom
Summary:
Use a bit set to keep track of which random number is generated.
        Currently only supports single-threaded. All our perf tests are run with threads=1
        Copied over bitset implementation from common/datastructures

Test Plan: printed the generated keys, and verified all keys were present.

Reviewers: MarkCallaghan, haobo, dhruba

Reviewed By: MarkCallaghan

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11247
2013-06-14 16:17:56 -07:00
Deon Nicholas
2a52e1dcb6 Fix db_bench for release build.
Test Plan: make release

Reviewers: haobo, dhruba, jpaton

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11307
2013-06-14 16:00:47 -07:00
Haobo Xu
1afdf28701 [RocksDB] Compaction Filter Cleanup
Summary: This hopefully gives the right semantics to compaction filter. Will write a small wiki to explain the ideas.

Test Plan: make check; db_stress

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11121
2013-06-14 14:23:08 -07:00
Abhishek Kona
7a5f71d19a [Rocksdb] measure table open io in a histogram
Summary: Table is setup for compaction using Table::SetupForCompaction. So read block calls can be differentiated b/w Gets/Compaction. Use this and measure times.

Test Plan: db_bench --statistics=1

Reviewers: dhruba, haobo

Reviewed By: haobo

CC: leveldb, MarkCallaghan

Differential Revision: https://reviews.facebook.net/D11217
2013-06-13 17:25:09 -07:00
Deon Nicholas
4985a9f73b [Rocksdb] [Multiget] Introduced multiget into db_bench
Summary:
Preliminary! Introduced the --use_multiget=1 and --keys_per_multiget=n
flags for db_bench. Also updated and tested the ReadRandom() method
to include an option to use multiget. By default,
keys_per_multiget=100.

Preliminary tests imply that multiget is at least 1.25x faster per
key than regular get.

Will continue adding Multiget for ReadMissing, ReadHot,
RandomWithVerify, ReadRandomWriteRandom; soon. Will also think
about ways to better verify benchmarks.

Test Plan:
1. make db_bench
2. ./db_bench --benchmarks=fillrandom
3. ./db_bench --benchmarks=readrandom --use_existing_db=1
	      --use_multiget=1 --threads=4 --keys_per_multiget=100
4. ./db_bench --benchmarks=readrandom --use_existing_db=1
	      --threads=4
5. Verify ops/sec (and 1000000 of 1000000 keys found)

Reviewers: haobo, MarkCallaghan, dhruba

Reviewed By: MarkCallaghan

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11127
2013-06-12 12:42:21 -07:00
Haobo Xu
bdf1085944 [RocksDB] cleanup EnvOptions
Summary:
This diff simplifies EnvOptions by treating it as POD, similar to Options.
- virtual functions are removed and member fields are accessed directly.
- StorageOptions is removed.
- Options.allow_readahead and Options.allow_readahead_compactions are deprecated.
- Unused global variables are removed: useOsBuffer, useFsReadAhead, useMmapRead, useMmapWrite

Test Plan: make check; db_stress

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11175
2013-06-12 11:17:19 -07:00
Dhruba Borthakur
e673d5d26d Do not submit multiple simultaneous seek-compaction requests.
Summary:
The code was such that if multi-threaded-compactions as well
as seek compaction are enabled then it submits multiple
compaction request for the same range of keys. This causes
extraneous sst-files to accumulate at various levels.

Test Plan:
I am not able to write a very good unit test for this one
but can easily reproduce this bug with 'dbstress' with the
following options.

batch=1;maxk=100000000;ops=100000000;ro=0;fm=2;bpl=10485760;of=500000; wbn=3; mbc=20; mb=2097152; wbs=4194304; dds=1; sync=0;  t=32; bs=16384; cs=1048576; of=500000; ./db_stress --disable_seek_compaction=0 --mmap_read=0 --threads=$t --block_size=$bs --cache_size=$cs --open_files=$of --verify_checksum=1 --db=/data/mysql/leveldb/dbstress.dir --sync=$sync --disable_wal=1 --disable_data_sync=$dds --write_buffer_size=$wbs --target_file_size_base=$mb --target_file_size_multiplier=$fm --max_write_buffer_number=$wbn --max_background_compactions=$mbc --max_bytes_for_level_base=$bpl --reopen=$ro --ops_per_thread=$ops --max_key=$maxk --test_batches_snapshots=$batch

Reviewers: leveldb, emayanke

Reviewed By: emayanke

Differential Revision: https://reviews.facebook.net/D11055
2013-06-10 15:49:19 -07:00
Dhruba Borthakur
1b69f1e584 Fix refering freed memory in earlier commit.
Summary: Fix refering freed memory in earlier commit by https://reviews.facebook.net/D11181

Test Plan: make check

Reviewers: haobo, sheki

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11193
2013-06-10 15:08:13 -07:00
Dhruba Borthakur
c5de1b9391 Print name of user comparator in LOG.
Summary:
The current code prints the name of the InternalKeyComparator
in the log file. We would also like to print the name of the
user-specified comparator for easier debugging.

Test Plan: make check

Reviewers: sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11181
2013-06-10 12:11:55 -07:00
Mayank Agarwal
184343a061 Max_mem_compaction_level can have maximum value of num_levels-1
Summary:
Without this files could be written out to a level greater than the maximum level possible and is the source of the segfaults that wormhole awas getting. The sequence of steps that was followed:
1. WriteLevel0Table was called when memtable was to be flushed for a file.
2. PickLevelForMemTableOutput was called to determine the level to which this file should be pushed.
3. PickLevelForMemTableOutput returned a wrong result because max_mem_compaction_level was equal to 2 even when num_levels was equal to 0.
The fix to re-initialize max_mem_compaction_level based on num_levels passed seems correct.

Test Plan: make all check; Also made a dummy file to mimic the wormhole-file behaviour which was causing the segfaults and found that the same segfault occurs without this change and not with this.

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11157
2013-06-09 10:38:55 -07:00
Abhishek Kona
e982b5a489 [Rocksdb] measure table open io in a histogram
Summary: as title

Test Plan: db_bench --statistics=1 check for statistic.

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11109
2013-06-07 10:02:28 -07:00
Deon Nicholas
db1f0cddf3 Fixed valgrind errors 2013-06-05 17:25:16 -07:00
Deon Nicholas
d8c7c45ea0 Very basic Multiget and simple test cases.
Summary:
Implemented the MultiGet operator which takes in a list of keys
and returns their associated values. Currently uses std::vector as its
container data structure. Otherwise, it works identically to "Get".

Test Plan:
 1. make db_test      ; compile it
 2. ./db_test         ; test it
 3. make all check    ; regress / run all tests
 4. make release      ; (optional) compile with release settings

Reviewers: haobo, MarkCallaghan, dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10875
2013-06-05 11:22:38 -07:00
Abhishek Kona
d91b42ee27 [Rocksdb] Measure all FSYNC/SYNC times
Summary: Add stop watches around all sync calls.

Test Plan: db_bench check if respective histograms are printed

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11073
2013-06-05 11:06:21 -07:00
Abhishek Kona
ee522d0032 [Rocksdb] Log on disable/enable file deletions
Summary: as title

Test Plan: compile

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11085
2013-06-05 10:48:24 -07:00