Commit Graph

3613 Commits

Author SHA1 Message Date
Maysam Yabandeh
ae05a83e19 Call ValidateOptions from SetOptions (#5368)
Summary:
Currently we validate options in DB::Open. However the validation step is missing when options are dynamically updated in ::SetOptions. The patch fixes that.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5368

Differential Revision: D15540101

Pulled By: maysamyabandeh

fbshipit-source-id: d27bbffd8f0252d1b50bcf59e0a70a278ed937f4
2019-06-03 19:49:57 -07:00
Siying Dong
5851cb7fdb Move util/trace_replay.* to trace_replay/ (#5376)
Summary:
util/ means for lower level libraries. trace_replay is highly integrated to DB and sometimes call DB. Move it out to a separate directory.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5376

Differential Revision: D15550938

Pulled By: siying

fbshipit-source-id: f46dce5ceffdc05a73f26379c7bb1b79ebe6c207
2019-06-03 13:25:26 -07:00
Siying Dong
000b9ec217 Move some logging related files to logging/ (#5387)
Summary:
Many logging related source files are under util/. It will be more structured if they are together.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5387

Differential Revision: D15579036

Pulled By: siying

fbshipit-source-id: 3850134ed50b8c0bb40a0c8ae1f184fa4081303f
2019-05-31 17:23:59 -07:00
Vijay Nadimpalli
cae22c53fb Make format
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5395

Differential Revision: D15581698

Pulled By: vjnadimpalli

fbshipit-source-id: f415972f16e784b1361714c202b97defcab46767
2019-05-31 15:24:43 -07:00
Vijay Nadimpalli
49c5a12dbe Organizing rocksdb/db directory
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5390

Differential Revision: D15579388

Pulled By: vjnadimpalli

fbshipit-source-id: 5bfc95e31554b8ff05b97b76d6534113f527f366
2019-05-31 11:57:01 -07:00
Zhongyi Xie
ab8f6c01a6 move LevelCompactionPicker to a separate file (#5369)
Summary:
In order to improve code readability, this PR moves LevelCompactionBuilder and LevelCompactionPicker to compaction_picker_level.h and .cc
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5369

Differential Revision: D15540172

Pulled By: miasantreble

fbshipit-source-id: c1a578b93f127cd63661b53f32b356e6edd349af
2019-05-30 21:38:24 -07:00
Sagar Vemuri
ff9d286877 Reorder DBImpl's private section (#5385)
Summary:
The methods and fields in the private section of DBImpl were all intermingled, making it hard to figure out where the fields/methods start and where they end. I cleaned up the code a little so that all the type declaration are at the beginning, followed by methods, and all the data fields are at the end. This follows
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5385

Differential Revision: D15566978

Pulled By: sagar0

fbshipit-source-id: 4618a7d819ad4e2d7cc9ae1af2c59f400140bb1b
2019-05-30 21:32:46 -07:00
Yanqin Jin
b9f5900658 Fix WAL replay by skipping old write batches (#5170)
Summary:
1. Fix a bug in WAL replay in which write batches with old sequence numbers are mistakenly inserted into memtables.
2. Add support for benchmarking secondary instance to db_bench_tool.
With changes made in this PR, we can start benchmarking secondary instance
using two processes. It is also possible to vary the frequency at which the
secondary instance tries to catch up with the primary. The info log of the
secondary can be found in a directory whose path can be specified with
'-secondary_path'.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5170

Differential Revision: D15564608

Pulled By: riversand963

fbshipit-source-id: ce97688ed3d33f69d3a0b9266ebbbbf887aa0ec8
2019-05-30 19:33:33 -07:00
Siying Dong
8843129ece Move some memory related files from util/ to memory/ (#5382)
Summary:
Move arena, allocator, and memory tools under util to a separate memory/ directory.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5382

Differential Revision: D15564655

Pulled By: siying

fbshipit-source-id: 9cd6b5d0d3d52b39606e19221fa154596e5852a5
2019-05-30 17:44:09 -07:00
Yanqin Jin
f1302ebab8 Add class-level comments to version-related classes (#5348)
Summary:
As title.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5348

Differential Revision: D15564595

Pulled By: riversand963

fbshipit-source-id: dd45aa86a70e0343c2e9ef702fad165163f548e6
2019-05-30 16:18:33 -07:00
Sagar Vemuri
1b59a490ef Fix flaky DBTest2.PresetCompressionDict test (#5378)
Summary:
Fix flaky DBTest2.PresetCompressionDict test.

This PR fixes two issues with the test:
1. Replaces `GetSstFiles` with `TotalSize`, which is based on `DB::GetColumnFamilyMetaData` so that only the size of the live SST files is taken into consideration when computing the total size of all sst files. Earlier, with `GetSstFiles`, even obsolete files were getting picked up.
1. In ZSTD compression, it is sometimes possible that using a trained dictionary is not better than using an untrained one. Using a trained dictionary performs well in 99% of the cases, but still in the remaining ~1% of the cases (out of 10000 runs) using an untrained dictionary gets better compression results.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5378

Differential Revision: D15559100

Pulled By: sagar0

fbshipit-source-id: c35adbf13871f520a2cec48f8bad9ff27ff7a0b4
2019-05-30 16:11:27 -07:00
Vijay Nadimpalli
50e470791d Organizing rocksdb/table directory by format
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5373

Differential Revision: D15559425

Pulled By: vjnadimpalli

fbshipit-source-id: 5d6d6d615582bedd96a4b879bb25d429a6de8b55
2019-05-30 14:51:11 -07:00
Sagar Vemuri
e62986260f Fix env_options_for_read spelling in CompactionJob
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5380

Differential Revision: D15563386

Pulled By: sagar0

fbshipit-source-id: 8b26aef47cfc40ff8016daf815582f21cdd40df2
2019-05-30 14:04:53 -07:00
Levi Tamasi
1e35584251 Move the index readers out of the block cache (#5298)
Summary:
Currently, when the block cache is used for index blocks as well, it is
not really the index block that is stored in the cache but an
IndexReader object. Since this object is not pure data (it has, for
instance, pointers that might dangle), it's not really sharable. To
avoid the issues around this, the current code uses a dummy unique cache
key for each TableReader to store the IndexReader, and erases the
IndexReader entry when the TableReader is closed. Instead of doing this,
the new code moves the IndexReader out of the cache altogether. In
particular, instead of the TableReader owning, or caching/pinning the
IndexReader based on the customer's settings, the TableReader
unconditionally owns the IndexReader, which in turn owns/caches/pins
the index block (which is itself sharable and thus can be safely put in
the cache without any hacks).

Note: the change has two side effects:
1) Partitions of partitioned indexes no longer affect the read
amplification statistics.
2) Eviction statistics for index blocks are temporarily broken. We plan to fix
this in a separate phase.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5298

Differential Revision: D15303203

Pulled By: ltamasi

fbshipit-source-id: 935a69ba59d87d5e44f42e2310619b790c366e47
2019-05-30 11:53:27 -07:00
Siying Dong
e9e0101ca4 Move test related files under util/ to test_util/ (#5377)
Summary:
There are too many types of files under util/. Some test related files don't belong to there or just are just loosely related. Mo
ve them to a new directory test_util/, so that util/ is cleaner.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5377

Differential Revision: D15551366

Pulled By: siying

fbshipit-source-id: 0f5c8653832354ef8caa31749c0143815d719e2c
2019-05-30 11:25:51 -07:00
anand76
a984040f0b Increase Trash/DB size ratio in DBSSTTest.RateLimitedWALDelete (#5366)
Summary:
By increasing the ratio, we ensure that all files go through background deletion and eliminate flakiness due to timing of deletions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5366

Differential Revision: D15549992

Pulled By: anand1976

fbshipit-source-id: d137375cd791fc1a802841412755d6e2b8fd7688
2019-05-30 11:12:59 -07:00
Zhongyi Xie
87fe4bcab8 Fix FIFO dynamic options sanitization (#5367)
Summary:
When dynamically setting options, we check the option type info and skip options that are marked deprecated. However this check is only done at top level, which results in bugs where SetOptions will corrupt option values and cause unexpected system behavior iff a deprecated second level option is set dynamically.
For exmaple, the following call:
```
dbfull()->SetOptions(
    {{"compaction_options_fifo",
        "{allow_compaction=true;max_table_files_size=1024;ttl=731;}"}});
```
was from pre 6.0 release when `ttl` was part of `compaction_options_fifo`. Now that it got moved out of `compaction_options_fifo`, this call will incorrectly set `compaction_options_fifo.max_table_files_size` to 731 (as `max_table_files_size` is the first one in `OptionsHelper::fifo_compaction_options_type_info` struct) and cause files to gett evicted much faster than expected.

This PR adds verification to second level options like `compaction_options_fifo.ttl` or `compaction_options_fifo.max_table_files_size` when set dynamically, and filter out those marked as deprecated.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5367

Differential Revision: D15530998

Pulled By: miasantreble

fbshipit-source-id: 818258be5c3abe09cd82d62f3c083572d70fecdd
2019-05-30 10:46:28 -07:00
Siying Dong
545d206040 Move some file related files outside util/ (#5375)
Summary:
util/ means for lower level libraries, so it's a good idea to move the files which requires knowledge to DB out. Create a file/ and move some files there.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5375

Differential Revision: D15550935

Pulled By: siying

fbshipit-source-id: 61a9715dcde5386eebfb43e93f847bba1ae0d3f2
2019-05-29 20:47:06 -07:00
Siying Dong
4d0c3b1f96 Add comments in compaction_picker.h
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5357

Differential Revision: D15522825

Pulled By: siying

fbshipit-source-id: d775386b9d10c7179f5d3af2c821ed213abfacdf
2019-05-28 12:24:38 -07:00
Zhongyi Xie
a466120cd5 improve comments in db_impl_secondary
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5360

Differential Revision: D15502973

Pulled By: miasantreble

fbshipit-source-id: 15b7f9d7928e771a6fac0643861173be8ba6b37a
2019-05-24 15:32:03 -07:00
anand76
029b98984e Add some comments in table_cache.h
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5343

Differential Revision: D15485831

Pulled By: anand1976

fbshipit-source-id: 8735ccfba90d7ecb3559e63f792e34527f04ed29
2019-05-24 14:26:43 -07:00
Siying Dong
6267ed251a Improve comment in db_impl.h (#5338)
Summary:
Add some comments in db_impl.h. Also reordered function order a little bit so that I can add a comment to flag the area of functions implementing DB interface.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5338

Differential Revision: D15498284

Pulled By: siying

fbshipit-source-id: 3d7c59c8303577fe44d13c74ae84c7ce05164f77
2019-05-24 13:09:55 -07:00
Siying Dong
f69e63dc5f Improve comments in compaction.h
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5356

Differential Revision: D15499033

Pulled By: siying

fbshipit-source-id: 069ae48669484beaf668dd90389b8743b3309dc3
2019-05-24 12:24:28 -07:00
Siying Dong
596cc1547a Update comments in column_family.h (#5347)
Summary:
Document relationships of data structures declared in column_family.h
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5347

Differential Revision: D15496941

Pulled By: siying

fbshipit-source-id: 47b37835abba26aa31a94fabea6b2775483e0ccb
2019-05-24 12:07:15 -07:00
Zhongyi Xie
767d1f3ff1 Improve comments for StatsHistoryIterator and InMemoryStatsHistoryIterator
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5346

Differential Revision: D15497679

Pulled By: miasantreble

fbshipit-source-id: c10caf10293c3d9663bfb398a0d331326d1e9e67
2019-05-24 11:40:05 -07:00
Zhongyi Xie
88ff80780b improve comment for WalManager (#5350)
Summary:
att
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5350

Differential Revision: D15496467

Pulled By: miasantreble

fbshipit-source-id: c29c0b143bf4df2040695a82be0feb9814ddb641
2019-05-24 10:40:30 -07:00
haoyuhuang
74a334a2eb Provide an option so that SST ingestion won't fall back to copy after hard linking fails (#5333)
Summary:
RocksDB always tries to perform a hard link operation on the external SST file to ingest. This operation can fail if the external SST resides on a different device/FS, or the underlying FS does not support hard link. Currently RocksDB assumes that if the link fails, the user is willing to perform file copy, which is not true according to the post. This commit provides an option named  'failed_move_fall_back_to_copy' for users to choose which behavior they want.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5333

Differential Revision: D15457597

Pulled By: HaoyuHuang

fbshipit-source-id: f3626e13f845db4f7ed970a53ec8a2b1f0d62214
2019-05-23 21:58:52 -07:00
Zhongyi Xie
09b534cc2f improve comments for CompactionJob (#5341)
Summary:
add class/function level comments to the header file
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5341

Differential Revision: D15485442

Pulled By: miasantreble

fbshipit-source-id: 9f11e2a1cd3ce0f4990f01353d0a6f4b050615cf
2019-05-23 16:57:46 -07:00
Siying Dong
02830a20f8 Add comments in db/dbformat.h
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5342

Differential Revision: D15485238

Pulled By: siying

fbshipit-source-id: a56b374584cb1d815c1173907a807d90b37d4dd6
2019-05-23 16:44:20 -07:00
Siying Dong
dc30a9b69b Add comments to db/db_iter.h (#5340)
Summary:
Add file comment in db/db_iter.h and minor changes in other parts.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5340

Differential Revision: D15484605

Pulled By: siying

fbshipit-source-id: 173771f9d5bd51303de5410ee5afd0a4af9d6572
2019-05-23 16:11:38 -07:00
Thomas Fersch
3d9d77d900 Restrict L0->L0 compaction according to max_compaction_bytes option (#5329)
Summary:
Modified FindIntraL0Compaction to stop picking more files if total
amount of compensated bytes would be larger than max_compaction_bytes
option.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5329

Differential Revision: D15435728

Pulled By: ThomasFersch

fbshipit-source-id: d118a6da88d5df8ee20944422ade37cf6b15d60c
2019-05-22 23:40:57 -07:00
haoyuhuang
518cd1a62a Use GetCurrentManifestPath to locate current MANIFEST file (#5331)
Summary:
In version_set.cc, there is a function GetCurrentManifestPath. The goal of this task is to refactor ListColumnFamilies function so that ListColumnFamilies calls GetCurrentManifestPath to search for MANIFEST.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5331

Differential Revision: D15444524

Pulled By: HaoyuHuang

fbshipit-source-id: 1dcbd030bc0f2e835695741f450bba150f2f2903
2019-05-22 09:21:56 -07:00
Siying Dong
b2274da0e5 LogWriter to only flush after finish generating whole record (#5328)
Summary:
Right now, in log writer, we call flush after writing each physical record. I don't see the necessarity of it. Right now, the underlying writer has a buffer, so there isn't a concern that the write request is too large either. On the other hand, in an Env where every flush is expensive, the current approach is significantly slower than only flushing after a whole record finishes, when the record is very large.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5328

Differential Revision: D15425032

Pulled By: siying

fbshipit-source-id: 440ebef002dfbb60c59d8388c9ddfc83d79700aa
2019-05-21 12:33:17 -07:00
Siying Dong
cd43446d01 Improve DBTablePropertiesTest.GetPropertiesOfTablesInRange (#5302)
Summary:
DBTablePropertiesTest.GetPropertiesOfTablesInRange sometimes hits the assert that generated LSM-tree doesn't have L1 file. Tighten the compaction triggering condition even further, hoping it goes away.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5302

Differential Revision: D15325971

Pulled By: siying

fbshipit-source-id: 3e032bdb16fe8d98d5fcfcd65dd8be9781f3d6ae
2019-05-20 13:50:53 -07:00
Vijay Nadimpalli
931c9df886 Use separate status code for column family drop and db shutdown in progress (#5275)
Summary:
Currently RocksDB uses Status::ShutdownInProgress to inform about column family drop. I would like to have a separate Status code for this event.
https://github.com/facebook/rocksdb/blob/master/include/rocksdb/status.h#L55
Comment on this:
abc4202e47/db/version_set.cc (L2742):L2743
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5275

Differential Revision: D15204583

Pulled By: vjnadimpalli

fbshipit-source-id: 95e99e34b27bc165b554ecb8a48a7f8e60f21e2a
2019-05-20 10:47:32 -07:00
Maysam Yabandeh
5c0e304170 WritePrepared: Clarify the need for two_write_queues in unordered_write (#5313)
Summary:
WritePrepared transactions when configured with two_write_queues=true offers higher throughput with unordered_write feature without however compromising the rocksdb guarantees. This is because it performs ordering among writes in a 2nd step that is not tied to memtable write speed. The 2nd step is naturally provided by 2PC when the commit phase does the ordering as well. Without 2PC, the 2nd step would only be provided when we use two_write_queues=true, where WritePrepared after performing the writes, in a 2nd step uses the 2nd queue to assign order to the writes.
The patch clarifies the need for two_write_queues=true in the HISTORY and inline comments of unordered_writes. Moreover it extends the stress tests of WritePrepared to unordred_write.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5313

Differential Revision: D15379977

Pulled By: maysamyabandeh

fbshipit-source-id: 5b6f05b9b59285dcbf3b0532215ba9fe7d926e00
2019-05-20 07:49:20 -07:00
Yanqin Jin
fb4c6a31ce Log replay integration for secondary instance (#5305)
Summary:
RocksDB secondary can replay both MANIFEST and WAL now.
On the one hand, the memory usage by memtables will grow after replaying WAL for sometime. On the other hand, replaying the MANIFEST can bring the database persistent data to a more recent point in time, giving us the opportunity to discard some memtables containing out-dated data.
This PR coordinates the MANIFEST and WAL replay, using the updates from MANIFEST replay to update the active memtable and immutable memtable list of each column family.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5305

Differential Revision: D15386512

Pulled By: riversand963

fbshipit-source-id: a3ea6fc415f8382d8cf624f52a71ebdcffa3e355
2019-05-17 19:19:51 -07:00
yiwu-arbug
f3a7847598 Reduce iterator key comparison for upper/lower bound check (#5111)
Summary:
Previously if iterator upper/lower bound presents, `DBIter` will check the bound for every key. This patch turns the check into per-file or per-data block check when applicable, by checking against either file largest/smallest key or block index key.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5111

Differential Revision: D15330061

Pulled By: siying

fbshipit-source-id: 8a653fe3cd50d94d81eb2d13b087326c58ee2024
2019-05-17 10:28:31 -07:00
Siying Dong
f82e693a31 RangeDelAggregator::StripeRep::Invalidate() to be skipped if empty (#5312)
Summary:
RangeDelAggregator::StripeRep::Invalidate() clears up several vectors. If we know there isn't anything to there, we can safe these small CPUs. Profiling shows that it sometimes take non-negligible amount of CPU. Worth a small optimization.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5312

Differential Revision: D15380511

Pulled By: siying

fbshipit-source-id: 53c5f34c33b4cb1e743643c6086ac56d0b84ec2e
2019-05-16 15:24:28 -07:00
Yanqin Jin
1583cb402e Fix a flaky test with test sync point (#5310)
Summary:
If DB is opened with `avoid_unnecessary_blocking_io` being true, then `~ColumnFamilyHandleImpl` enqueues a purge request and schedules a background thread to perform the deletion. Without test sync point, whether the SST file is purged or not at a later point in time is not deterministic. If the SST does not exist, it will cause an assertion failure.

How to reproduce:
```
$git checkout 6492430eaf
$make -j20 deletefile_test
$gtest-parallel --repeat 1000 --worker 16 ./deletefile_test --gtest_filter=DeleteFileTest.BackgroundPurgeCFDropTest
```
The test may fail a few times.
With changes made in this PR, repeat the above commands, and the test should not fail.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5310

Differential Revision: D15361136

Pulled By: riversand963

fbshipit-source-id: c4308d5f8da83472c893bf7f8ceed347fbfa850f
2019-05-15 15:17:55 -07:00
Maysam Yabandeh
f0e8216197 WritePrepared: Fix deadlock in WriteRecoverableState (#5306)
Summary:
The recent improvement in https://github.com/facebook/rocksdb/pull/3661 could cause a deadlock: When writing recoverable state, we also commit its sequence number to commit table, which could result into evicting existing commit entry, which could result into advancing max_evicted_seq_, which would need to get snapshots from database, which requires obtaining db mutex. The patch releases db_mutex before calling the callback in WriteRecoverableState to avoid the potential deadlock. It also improves the stress tests to let the issue be manifested in the tests.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5306

Differential Revision: D15341458

Pulled By: maysamyabandeh

fbshipit-source-id: 05dcbed7e21b789fd1e5fd5ee8eea08077162323
2019-05-15 13:53:54 -07:00
Thomas Fersch
a42757607d Use pre-increment instead of post-increment for iterators (#5296)
Summary:
Google C++ style guide indicates pre-increment should be used for iterators: https://google.github.io/styleguide/cppguide.html#Preincrement_and_Predecrement. Replaced all instances of ' it++' by ' ++it' (where type is iterator). So this covers the cases where iterators are named 'it'.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5296

Differential Revision: D15301256

Pulled By: tfersch

fbshipit-source-id: 2803483c1392504ad3b281d21db615429c71114b
2019-05-15 13:19:15 -07:00
Maysam Yabandeh
3c3252a06a Fix tsan complaint in ConcurrentMergeWrite test (#5308)
Summary:
The test was not using separate MemTablePostProcessInfo per memetable insert thread and thus tsan was complaining about data race.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5308

Differential Revision: D15356420

Pulled By: maysamyabandeh

fbshipit-source-id: 46c2f2d19fb02c3c775b587aa09ca9c0dae6ed04
2019-05-15 11:21:48 -07:00
anand76
6492430eaf Fix a bug in db_stress and an incorrect assertion in FilePickerMultiGet (#5301)
Summary:
This PR has two fixes for crash test failures -
1. Fix a bug in TestMultiGet() in db_stress that was passing list of key to MultiGet() in the wrong order, thus ensuring that actual values don't match expected values
2. Remove an incorrect assertion in FilePickerMultiGet::GetNextFileInLevelWithKeys() that checks that files in a level are in sorted order. This is not true with MultiGet(), especially if there are duplicate keys and we may have to go back one file for the next key. Furthermore, this assertion makes more sense when a new version is created, rather than at lookup time

Test -
asan_crash and ubsan_crash tests
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5301

Differential Revision: D15337383

Pulled By: anand1976

fbshipit-source-id: 35092cb15bbc1700e5e823cbe07bfa62f1e9e6c6
2019-05-14 11:58:04 -07:00
Maysam Yabandeh
f383641a1d Unordered Writes (#5218)
Summary:
Performing unordered writes in rocksdb when unordered_write option is set to true. When enabled the writes to memtable are done without joining any write thread. This offers much higher write throughput since the upcoming writes would not have to wait for the slowest memtable write to finish. The tradeoff is that the writes visible to a snapshot might change over time. If the application cannot tolerate that, it should implement its own mechanisms to work around that. Using TransactionDB with WRITE_PREPARED write policy is one way to achieve that. Doing so increases the max throughput by 2.2x without however compromising the snapshot guarantees.
The patch is prepared based on an original by siying
Existing unit tests are extended to include unordered_write option.

Benchmark Results:
```
TEST_TMPDIR=/dev/shm/ ./db_bench_unordered --benchmarks=fillrandom --threads=32 --num=10000000 -max_write_buffer_number=16 --max_background_jobs=64 --batch_size=8 --writes=3000000 -level0_file_num_compaction_trigger=99999 --level0_slowdown_writes_trigger=99999 --level0_stop_writes_trigger=99999 -enable_pipelined_write=false -disable_auto_compactions  --unordered_write=1
```
With WAL
- Vanilla RocksDB: 78.6 MB/s
- WRITER_PREPARED with unordered_write: 177.8 MB/s (2.2x)
- unordered_write: 368.9 MB/s (4.7x with relaxed snapshot guarantees)

Without WAL
- Vanilla RocksDB: 111.3 MB/s
- WRITER_PREPARED with unordered_write: 259.3 MB/s MB/s (2.3x)
- unordered_write: 645.6 MB/s (5.8x with relaxed snapshot guarantees)

- WRITER_PREPARED with unordered_write disable concurrency control: 185.3 MB/s MB/s (2.35x)

Limitations:
- The feature is not yet extended to `max_successive_merges` > 0. The feature is also incompatible with `enable_pipelined_write` = true as well as with `allow_concurrent_memtable_write` = false.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5218

Differential Revision: D15219029

Pulled By: maysamyabandeh

fbshipit-source-id: 38f2abc4af8780148c6128acdba2b3227bc81759
2019-05-13 17:47:21 -07:00
Yanqin Jin
e626016545 Fix a race condition caused by unlocking db mutex (#5294)
Summary:
Previous code may call `~ColumnFamilyData` in `DBImpl::AtomicFlushMemTablesToOutputFiles` if the column family is dropped or `cfd->IsFlushPending() == false`. In `~ColumnFamilyData`, the db mutex is released briefly and re-acquired. This can cause correctness issue. The reason is as follows.

Assume there are more bg flush threads. After bg_flush_thr1 releases the db mutex, bg_flush_thr2 can grab it and pop an element from the flush queue. This will cause bg_flush_thr2 to accidentally pick some memtables which should have been picked by bg_flush_thr1. To make the matter worse, bg_flush_thr2 can clear `flush_requested_` flag for the memtable list, causing a subsequent call to `MemTableList::IsFlushPending()` by bg_flush_thr1 to return false, which is wrong.

The fix is to delay `ColumnFamilyData::Unref` and `~ColumnFamilyData` for column families not selected for flush until `AtomicFlushMemTablesToOutputFiles` returns. Furthermore, a bg flush thread should not clear `MemTableList::flush_requested_` in `MemTableList::PickMemtablesToFlush` unless atomic flush is not used **or** the memtable list does not have unpicked memtables.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5294

Differential Revision: D15295297

Pulled By: riversand963

fbshipit-source-id: 03b101205ca22c242647cbf488bcf0ed80b2ecbd
2019-05-10 17:56:48 -07:00
Jelte Fennema
6451673f37 Add C bindings for LowerThreadPoolIO/CPUPriority (#5285)
Summary:
There were no C bindings for lowering thread pool priority. This adds those.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5285

Differential Revision: D15290050

Pulled By: siying

fbshipit-source-id: b2ed94d0c39d27434ace2204829a242b53d0d67a
2019-05-09 18:21:21 -07:00
Siying Dong
9fad3e21eb Merging iterator to avoid child iterator reseek for some cases (#5286)
Summary:
When reseek happens in merging iterator, reseeking a child iterator can be avoided if:
(1) the iterator represents imutable data
(2) reseek() to a larger key than the current key
(3) the current key of the child iterator is larger than the seek key
because it is guaranteed that the result will fall into the same position.

This optimization will be useful for use cases where users keep seeking to keys nearby in ascending order.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5286

Differential Revision: D15283635

Pulled By: siying

fbshipit-source-id: 35f79ffd5ce3609146faa8cd55f2bfd733502f83
2019-05-09 14:20:04 -07:00
anand76
181bb43f08 Fix bugs in FilePickerMultiGet (#5292)
Summary:
This PR fixes a couple of bugs in FilePickerMultiGet that were causing db_stress test failures. The failures were caused by -
1. Improper handling of a key that matches the user key portion of an L0 file's largest key. In this case, the curr_index_in_curr_level file index in L0 for that key was getting incremented, but batch_iter_ was not advanced. By design, all keys in a batch are supposed to be checked against an L0 file before advancing to the next L0 file. Not advancing to the next key in the batch was causing a double increment of curr_index_in_curr_level due to the same key being processed again
2. Improper handling of a key that matches the user key portion of the largest key in the last file of L1 and higher. This was resulting in a premature end to the processing of the batch for that level when the next key in the batch is a duplicate. Typically, the keys in MultiGet will not be duplicates, but its good to handle that case correctly

Test -
asan_crash
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5292

Differential Revision: D15282530

Pulled By: anand1976

fbshipit-source-id: d1a6a86e0af273169c3632db22a44d79c66a581f
2019-05-09 13:18:00 -07:00
Siying Dong
25d81e4577 DBIter::Next() can skip user key checking if previous entry's seqnum is 0 (#5244)
Summary:
Right now, DBIter::Next() always checks whether an entry is for the same user key as the previous entry to see whether the key should be hidden to the user. However, if previous entry's sequence number is 0, the check is not needed because 0 is the oldest possible sequence number.

We could extend it from seqnum 0 case to simply prev_seqno >= current_seqno. However, it is less robust with bug or unexpected situations, while the gain is relatively low. We can always extend it later when needed.

In a readseq benchmark with full formed LSM-tree, number of key comparisons called is reduced from 2.981 to 2.165. readseq against a fully compacted DB, no key comparison is called. Performance in this benchmark didn't show obvious improvement, which is expected because key comparisons only takes small percentage of CPU. But it may show up to be more effective if users have an expensive customized comparator.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5244

Differential Revision: D15067257

Pulled By: siying

fbshipit-source-id: b7e1ef3ec4fa928cba509683d2b3246e35d270d9
2019-05-09 12:24:04 -07:00