Commit Graph

115 Commits

Author SHA1 Message Date
sdong 66b5613d0c row_cache to share entry for recent snapshots (#5600)
Summary:
Right now, users cannot take advantage of row cache, unless no snapshot is used, or Get() is repeated for the same snapshots. This limits the usage of row cache.
This change eliminate this restriction in some cases. If the snapshot used is newer than the largest sequence number in the file, and write callback function is not registered, the same row cache key is used as no snapshot is given. We still need the callback function restriction for now because the callback function may filter out different keys for different snapshots even if the snapshots are new.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5600

Test Plan: Add a unit test.

Differential Revision: D16386616

fbshipit-source-id: 6b7d214bd215d191b03ccf55926ad4b703ec2e53
2019-07-22 18:56:19 -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
Siying Dong 4e0f2aadb0 DB::Close() to fail when there are unreleased snapshots (#5272)
Summary:
Sometimes, users might make mistake of not releasing snapshots before closing the DB. This is undocumented use of RocksDB and the behavior is unknown. We return DB::Close() to provide a way to check it for the users. Aborted() will be returned to users when they call DB::Close().
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5272

Differential Revision: D15159713

Pulled By: siying

fbshipit-source-id: 39369def612398d9f239d83d396b5a28e5af65cd
2019-05-01 10:17:30 -07:00
Zhongyi Xie baa5302447 Avoid double-compacting data in bottom level in manual compactions (#5138)
Summary:
Depending on the config, manual compaction (leveled compaction style) does following compactions:
L0->L1
L1->L2
...
Ln-1 -> Ln
Ln -> Ln
The final Ln -> Ln compaction is partly unnecessary as it recompacts all the files that were just generated by the Ln-1 -> Ln. We should avoid recompacting such files. This rule should be applied to Lmax only.
Resolves issue https://github.com/facebook/rocksdb/issues/4995
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5138

Differential Revision: D14940106

Pulled By: miasantreble

fbshipit-source-id: 8d3cf5507a17e76f3333cfd4bac5256d005636e5
2019-04-16 23:32:20 -07:00
Siying Dong beb44ec3eb WriteBufferManager's dummy entry size to block cache 1MB -> 256KB (#5175)
Summary:
Dummy cache size of 1MB is too large for small block sizes. Our GetDefaultCacheShardBits() use min_shard_size = 512L * 1024L to determine number of shards, so 1MB will excceeds the size of the whole shard and make the cache excceeds the budget.
Change it to 256KB accordingly.
There shouldn't be obvious performance impact, since inserting a cache entry every 256KB of memtable inserts is still infrequently enough.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5175

Differential Revision: D14954289

Pulled By: siying

fbshipit-source-id: 2c275255c1ac3992174e06529e44c55538325c94
2019-04-16 12:03:07 -07:00
Siying Dong 85b2bde3dd Still implement StatisticsImpl::measureTime() (#5181)
Summary:
Since Statistics::measureTime() is deprecated, StatisticsImpl::measureTime() is not implemented. We realized that users might have a wrapped Statistics implementation in which measureTime() is implemented as forwarded to StatisticsImpl, and causes assert failure. In order to make the change less intrusive, we implement StatisticsImpl::measureTime(). We will revisit whether we need to remove it after several releases.

Also, add a test to make sure that a Statistics implementation using the old interface still works.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5181

Differential Revision: D14907089

Pulled By: siying

fbshipit-source-id: 29b6202fd04e30ed6f6adcaeb1000e87f10d1e1a
2019-04-12 11:00:35 -07:00
Siying Dong ed9f5e21aa Change OptimizeForPointLookup() and OptimizeForSmallDb() (#5165)
Summary:
Change the behavior of OptimizeForSmallDb() so that it is less likely to go out of memory.
Change the behavior of OptimizeForPointLookup() to take advantage of the new memtable whole key filter, and move away from prefix extractor as well as hash-based indexing, as they are prone to misuse.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5165

Differential Revision: D14880709

Pulled By: siying

fbshipit-source-id: 9af30e3c9e151eceea6d6b38701a58f1f9fb692d
2019-04-11 10:45:36 -07:00
Zhichao Cao ebb9b2ed16 Fix the potential DB crash caused by call EndTrace before StartTrace (#5130)
Summary:
Although user should first call StartTrace to begin the RocksDB tracing function and call EndTrace to stop the tracing process, user can accidentally call EndTrace first. It will cause segment fault and crash the DB instance. The issue is fixed by checking the pointer first.

Test case added in db_test2.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5130

Differential Revision: D14691420

Pulled By: zhichao-cao

fbshipit-source-id: 3be13d2f944bc453728ef8eef67b68d7ad0939c8
2019-04-03 13:26:34 -07:00
Maysam Yabandeh 14b3f683a1 WriteUnPrepared: less virtual in iterator callback (#5049)
Summary:
WriteUnPrepared adds a virtual function, MaxUnpreparedSequenceNumber, to ReadCallback, which returns 0 unless WriteUnPrepared is enabled and the transaction has uncommitted data written to the DB. Together with snapshot sequence number, this determines the last sequence that is visible to reads.
The patch clarifies the guarantees of the GetIterator API in WriteUnPrepared transactions and make use of that to statically initialize the read callback and thus avoid the virtual call.
Furthermore it increases the minimum value for min_uncommitted from 0 to 1 as seq 0 is used only for last level keys that are committed in all snapshots.

The following benchmark shows +0.26% higher throughput in seekrandom benchmark.

Benchmark:
./db_bench --benchmarks=fillrandom --use_existing_db=0 --num=1000000 --db=/dev/shm/dbbench

./db_bench --benchmarks=seekrandom[X10] --use_existing_db=1 --db=/dev/shm/dbbench --num=1000000 --duration=60 --seek_nexts=100
seekrandom [AVG    10 runs] : 20355 ops/sec;  225.2 MB/sec
seekrandom [MEDIAN 10 runs] : 20425 ops/sec;  225.9 MB/sec

./db_bench_lessvirtual3 --benchmarks=seekrandom[X10] --use_existing_db=1 --db=/dev/shm/dbbench --num=1000000 --duration=60 --seek_nexts=100
seekrandom [AVG    10 runs] : 20409 ops/sec;  225.8 MB/sec
seekrandom [MEDIAN 10 runs] : 20487 ops/sec;  226.6 MB/sec
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5049

Differential Revision: D14366459

Pulled By: maysamyabandeh

fbshipit-source-id: ebaff8908332a5ae9af7defeadabcb624be660ef
2019-04-02 14:47:16 -07:00
Shi Feng 01e6badbb6 Introduce CPU timers for iterator seek and next (#5076)
Summary:
Introduce CPU timers for iterator seek and next operations. Seek
counter includes SeekToFirst, SeekToLast and SeekForPrev, w/ the
caveat that SeekToLast timer doesn't include some post processing
time if upper bound is defined.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5076

Differential Revision: D14525218

Pulled By: fredfsh

fbshipit-source-id: 03ba25df3b22b06c072621e4de0eacfa1445f0d9
2019-03-26 16:32:13 -07:00
Wenjie Yang 36c2a7cfb1 Add an option to filter traces (#5082)
Summary:
Add an option to filter out READ or WRITE operations while tracing.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5082

Differential Revision: D14515083

Pulled By: mrmiywj

fbshipit-source-id: 2504c89a9abf1dd629cad44b4104092702d77610
2019-03-19 14:36:51 -07:00
Maysam Yabandeh a661c0d208 WritePrepared: optimize read path by avoiding virtual (#5018)
Summary:
The read path includes a callback function, ReadCallback, which would eventually calls IsInSnapshot to figure if a particular seq is in the reading snapshot or not. This callback is virtual, which adds the cost of multiple virtual function call to each read. The first few checks in IsInSnapshot, however, are quite trivial and take care of majority of the cases. The patch moves those to a non-virtual function in the the parent class, ReadCallback, to lower the virtual callback cost.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5018

Differential Revision: D14226562

Pulled By: maysamyabandeh

fbshipit-source-id: 6feed5b34f3b082e52092c5ef143e29b49c46b44
2019-02-26 16:56:19 -08:00
Siying Dong 93f7e7a450 Temporarily Disable DBTest2.PresetCompressionDict (#5003)
Summary:
DBTest2.PresetCompressionDict is flaky. Temparily disable it for now.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5003

Differential Revision: D14139505

Pulled By: siying

fbshipit-source-id: ebf1872d364b76b2cb021b489ea2f17ee997116a
2019-02-19 14:44:12 -08:00
Michael Liu ca89ac2ba9 Apply modernize-use-override (2nd iteration)
Summary:
Use C++11’s override and remove virtual where applicable.
Change are automatically generated.

Reviewed By: Orvid

Differential Revision: D14090024

fbshipit-source-id: 1e9432e87d2657e1ff0028e15370a85d1739ba2a
2019-02-14 14:41:36 -08:00
Andrew Kryczka 62f70f6d14 Reduce scope of compression dictionary to single SST (#4952)
Summary:
Our previous approach was to train one compression dictionary per compaction, using the first output SST to train a dictionary, and then applying it on subsequent SSTs in the same compaction. While this was great for minimizing CPU/memory/I/O overhead, it did not achieve good compression ratios in practice. In our most promising potential use case, moderate reductions in a dictionary's scope make a major difference on compression ratio.

So, this PR changes compression dictionary to be scoped per-SST. It accepts the tradeoff during table building to use more memory and CPU. Important changes include:

- The `BlockBasedTableBuilder` has a new state when dictionary compression is in-use: `kBuffered`. In that state it accumulates uncompressed data in-memory whenever `Add` is called.
- After accumulating target file size bytes or calling `BlockBasedTableBuilder::Finish`, a `BlockBasedTableBuilder` moves to the `kUnbuffered` state. The transition (`EnterUnbuffered()`) involves sampling the buffered data, training a dictionary, and compressing/writing out all buffered data. In the `kUnbuffered` state, a `BlockBasedTableBuilder` behaves the same as before -- blocks are compressed/written out as soon as they fill up.
- Samples are now whole uncompressed data blocks, except the final sample may be a partial data block so we don't breach the user's configured `max_dict_bytes` or `zstd_max_train_bytes`. The dictionary trainer is supposed to work better when we pass it real units of compression. Previously we were passing 64-byte KV samples which was not realistic.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4952

Differential Revision: D13967980

Pulled By: ajkr

fbshipit-source-id: 82bea6f7537e1529c7a1a4cdee84585f5949300f
2019-02-11 19:47:32 -08:00
tang-jianfeng 08809f5e6c Implement trace sampling (#4963)
Summary:
Implement trace sampling to allow user to specify the sampling frequency, i.e. save one per how many requests, so that a user does not need to log all if he/she is interested in only a sampled set.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4963

Differential Revision: D14011190

Pulled By: tang-jianfeng

fbshipit-source-id: 078b631d9319b67cb089dd2c30e21d0df8dc406a
2019-02-08 18:08:18 -08:00
Alexander Zinoviev 32a6dd9a41 Add a new CPU time counter to compaction report (#4889)
Summary:
Measure CPU time consumed for a compaction and report it in the stats report
Enable NowCPUNanos() to work for MacOS
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4889

Differential Revision: D13701276

Pulled By: zinoale

fbshipit-source-id: 5024e5bbccd4dd10fd90d947870237f436445055
2019-01-29 17:24:00 -08:00
Andrew Kryczka 01013ae766 Digest ZSTD compression dictionary once when writing SST file (#4849)
Summary:
This is essentially a re-submission of #4251 with a few improvements:

- Split `CompressionDict` into two separate classes: `CompressionDict` and `UncompressionDict`
- Eliminated `Init` functions. Instead do all initialization work in constructors.
- Added test case for parallel DB open, which is the scenario where #4251 failed under TSAN.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4849

Differential Revision: D13606039

Pulled By: ajkr

fbshipit-source-id: 08c236059798c710db9cbf545fce0f371232d447
2019-01-18 19:12:57 -08:00
Maysam Yabandeh d56ac22b44 Remove duplicates from SnapshotList::GetAll (#4860)
Summary:
The vector returned by SnapshotList::GetAll could have duplicate entries if two separate snapshots have the same sequence number. However, when this vector is used in compaction the duplicate entires are of no use and could be safely ignored. Moreover not having duplicate entires simplifies reasoning in the compaction_iterator.cc code. For example when searching for the previous_snap we currently use the snapshot before the current one but the way the code uses that it expects it to be also less than the current snapshot, which would be simpler to read if there is no duplicate entry in the snapshot list.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4860

Differential Revision: D13615502

Pulled By: maysamyabandeh

fbshipit-source-id: d45bf01213ead5f39db811f951802da6fcc3332b
2019-01-09 16:25:42 -08:00
Siying Dong 8641e9adf7 Non-initial file preloading should always prefetch index and filter (#4852)
Summary:
https://github.com/facebook/rocksdb/pull/3340 introduces preloading when max_open_files != -1.
It doesn't preload index and filter in non-initial file loading case. This is a little bit too
complicated to understand. We observed in one MyRocks use case where the filter is expected to be
preloaded but is not. To simplify the use case, we simply always prefetch the index and filter.
They anyway is expected to be loaded in the file verification phase anyway.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4852

Differential Revision: D13595402

Pulled By: siying

fbshipit-source-id: d4d8624eb3e849e20aeb990df2100502d85aff31
2019-01-08 12:47:34 -08:00
Siying Dong f0dda35d7d Preload some files even if options.max_open_files (#3340)
Summary:
Choose to preload some files if options.max_open_files != -1. This can slightly narrow the gap of performance between options.max_open_files is -1 and a large number. To avoid a significant regression to DB reopen speed if options.max_open_files != -1. Limit the files to preload in DB open time to 16.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3340

Differential Revision: D6686945

Pulled By: siying

fbshipit-source-id: 8ec11bbdb46e3d0cdee7b6ad5897a09c5a07869f
2018-12-28 18:02:28 -08:00
Siying Dong da1c64b6e7 Introduce a CPU time counter in perf_context (#4741)
Summary:
Introduce the first CPU timing counter, perf_context.get_cpu_nanos. This opens a door to more CPU counters in the future.
Only Posix Env has it implemented using clock_gettime() with CLOCK_THREAD_CPUTIME_ID. How accurate the counter is depends on the platform.
Make PerfStepTimer to take an Env as an argument, and sometimes pass it in. The direct reason is to make the unit tests to use SpecialEnv where we can ingest logic there. But in long term, this is a good change.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4741

Differential Revision: D13287798

Pulled By: siying

fbshipit-source-id: 090361049d9d5095d1d1a369fe1338d2e2e1c73f
2018-12-20 12:03:44 -08:00
Zhichao Cao 7125e24619 Add the max trace file size limitation option to Tracing (#4610)
Summary:
If user do not end the trace manually, the tracing will continue which can potential use up all the storage space and cause problem. In this PR, the max trace file size is added to the TraceOptions and user can set the value if they need or the default is 64GB.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4610

Differential Revision: D12893400

Pulled By: zhichao-cao

fbshipit-source-id: acf4b5a6076bb691778bdfbac4864e1006758953
2018-11-27 14:27:05 -08:00
Siying Dong 13579e8c5a WriteBufferManger doens't cost to cache if no limit is set (#4695)
Summary:
WriteBufferManger is not invoked when allocating memory for memtable if the limit is not set even if a cache is passed. It is inconsistent from the comment syas. Fix it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4695

Differential Revision: D13112722

Pulled By: siying

fbshipit-source-id: 0b27eef63867f679cd06033ea56907c0569597f4
2018-11-18 16:55:43 -08:00
Siying Dong abb1a8fc23 Add a unit test to assert number of preads (#4657)
Summary:
We used to have a bug, which caused every block to be read twice, and none of our tests caught it. Add a very simply unit test to make sure that when reading a data block, we only issue one pread against the SST file.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4657

Differential Revision: D13005260

Pulled By: siying

fbshipit-source-id: 03167b554ad2451192b1707415536d7d05e9026c
2018-11-13 12:52:19 -08:00
Sagar Vemuri 2993cd2002 Fix RocksDB Lite build (#4675)
Summary:
Our internal CI test caught RocksDB Lite build failures. The failures are due to a new test introduced in #4665 using `SSTFileWriter` and `IngestExternalFile`, but these is not exposed under lite mode. Fixed by #ifdef'ing out the test.

```
db/db_test2.cc: In member function ‘virtual void rocksdb::DBTest2_TestCompactFiles_Test::TestBody()’:
db/db_test2.cc:2907:3: error: ‘SstFileWriter’ is not a member of ‘rocksdb’
   rocksdb::SstFileWriter sst_file_writer{rocksdb::EnvOptions(), options};
   ^
In file included from ./util/testharness.h:15:0,
                 from ./table/mock_table.h:23,
                 from ./db/db_test_util.h:44,
                 from db/db_test2.cc:13:
db/db_test2.cc:2912:13: error: ‘sst_file_writer’ was not declared in this scope
   ASSERT_OK(sst_file_writer.Open(external_file1));
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4675

Differential Revision: D13035984

Pulled By: sagar0

fbshipit-source-id: c1ceac550dfac1a85eeea436693dc7dd467519a6
2018-11-12 19:01:37 -08:00
DorianZheng 0f88160f67 Fix `CompactFiles` bug (#4665)
Summary:
`CompactFiles` gets `SuperVersion` before `WaitForIngestFile`, while `IngestExternalFile` may add files that overlap with `input_file_names`

The timeline of execution flow is as follow:

Let's say that level N has two file [1,2] and [5,6]
```
timeline              user_thread1                             user_thread2
t0   |      CompactFiles([1, 2], [5, 6]) begin
t1   |         GetReferencedSuperVersion()
t2   |                                              IngestExternalFile([3,4]) to level N begin
t3   |             CompactFiles resume
     V
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4665

Differential Revision: D13030674

Pulled By: ajkr

fbshipit-source-id: 8be19477fd6e505032267a979d32f3097cc3be51
2018-11-12 14:32:18 -08:00
Sagar Vemuri dc3528077a Update all unique/shared_ptr instances to be qualified with namespace std (#4638)
Summary:
Ran the following commands to recursively change all the files under RocksDB:
```
find . -type f -name "*.cc" -exec sed -i 's/ unique_ptr/ std::unique_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/<unique_ptr/<std::unique_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/ shared_ptr/ std::shared_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/<shared_ptr/<std::shared_ptr/g' {} +
```
Running `make format` updated some formatting on the files touched.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4638

Differential Revision: D12934992

Pulled By: sagar0

fbshipit-source-id: 45a15d23c230cdd64c08f9c0243e5183934338a8
2018-11-09 11:19:58 -08:00
Peter Pei 09814f2cfc support OnCompactionBegin (#4431)
Summary:
fix #4288

Add `OnCompactionBegin` support to `rocksdb::EventListener`.

Currently, we only have these three callbacks:

- OnFlushBegin
- OnFlushCompleted
- OnCompactionCompleted

As paolococchi requested in #4288 , and ajkr agreed, we should also support `OnCompactionBegin`.

This PR is a try to implement the support of `OnCompactionBegin`.

Hope it is useful to you.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4431

Differential Revision: D10055515

Pulled By: yiwu-arbug

fbshipit-source-id: 39c0f95f8e9ff1c7ca3a10787502a17f258d2334
2018-10-10 17:32:27 -07:00
DorianZheng 27090ae8f6 Fix DBImpl::GetColumnFamilyHandleUnlocked race condition (#4391)
Summary:
- Fix DBImpl API race condition

The timeline of execution flow is as follow:
```
timeline              user_thread1                      user_thread2
t1   |     cfh = GetColumnFamilyHandleUnlocked(0)
t2   |     id1 = cfh->GetID()
t3   |                                                GetColumnFamilyHandleUnlocked(1)
t4   |     id2 = cfh->GetID()
     V
```
The original implementation return a pointer to a stateful variable, so that the return `ColumnFamilyHandle` will be changed when another thread calls `GetColumnFamilyHandleUnlocked` with different `column family id`

- Expose ColumnFamily ID to compaction event listener

- Fix the return status of `DBImpl::GetLatestSequenceForKey`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4391

Differential Revision: D10221243

Pulled By: yiwu-arbug

fbshipit-source-id: dec60ee9ff0c8261a2f2413a8506ec1063991993
2018-10-08 14:24:16 -07:00
Sagar Vemuri 3db584059c Remove sync point from Block destructor (#4370)
Summary:
AddressSanitizer: heap-use-after-free in std::__atomic_base<bool>::load(std::memory_order) const
==1798517==ABORTING
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4370

Differential Revision: D9844146

Pulled By: sagar0

fbshipit-source-id: 18a2970b1d504b4f6c8fb04857f26e0f32124dd1
2018-09-15 00:12:57 -07:00
Siying Dong f3d91a0b57 Add a unit test to verify iterators release data blocks after using them (#4170)
Summary:
Add a unit test to check that iterators release data blocks after it has moved away from it. Verify the same for compaction input iterators.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4170

Differential Revision: D8962513

Pulled By: siying

fbshipit-source-id: 05a5b604d7d29887fb488f2cda7286f554a14407
2018-08-13 17:43:14 -07:00
Zhichao Cao 6d75319d95 Add tracing function of Seek() and SeekForPrev() to trace_replay (#4228)
Summary:
In the current trace_and replay, Get an WriteBatch are traced. This pull request track down the Seek() and SeekForPrev() to the trace file. <target_key, timestamp, column_family_id> are write to the file.

Replay of Iterator is not supported in the current implementation.

Tested with trace_analyzer.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4228

Differential Revision: D9201381

Pulled By: zhichao-cao

fbshipit-source-id: 6f9cc9cb3c20260af741bee065ec35c5c96354ab
2018-08-10 17:57:40 -07:00
Sagar Vemuri 12b6cdeed3 Trace and Replay for RocksDB (#3837)
Summary:
A framework for tracing and replaying RocksDB operations.

A binary trace file is created by capturing the DB operations, and it can be replayed back at the same rate using db_bench.

- Column-families are supported
- Multi-threaded tracing is supported.
- TraceReader and TraceWriter are exposed to the user, so that tracing to various destinations can be enabled (say, to other messaging/logging services). By default, a FileTraceReader and FileTraceWriter are implemented to capture to a file and replay from it.
- This is not yet ideal to be enabled in production due to large performance overhead, but it can be safely tried out in a shadow setup, say, for analyzing RocksDB operations.

Currently supported DB operations:
- Writes:
-- Put
-- Merge
-- Delete
-- SingleDelete
-- DeleteRange
-- Write
- Reads:
-- Get (point lookups)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3837

Differential Revision: D7974837

Pulled By: sagar0

fbshipit-source-id: 8ec65aaf336504bc1f6ed0feae67f6ed5ef97a72
2018-08-01 00:27:08 -07:00
Siying Dong 8425c8bd4d BlockBasedTableReader: automatically adjust tail prefetch size (#4156)
Summary:
Right now we use one hard-coded prefetch size to prefetch data from the tail of the SST files. However, this may introduce a waste for some use cases, while not efficient for others.
Introduce a way to adjust this prefetch size by tracking 32 recent times, and pick a value with which the wasted read is less than 10%
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4156

Differential Revision: D8916847

Pulled By: siying

fbshipit-source-id: 8413f9eb3987e0033ed0bd910f83fc2eeaaf5758
2018-07-20 14:43:37 -07:00
Maysam Yabandeh 8581a93a6b Per-thread unique test db names (#4135)
Summary:
The patch makes sure that two parallel test threads will operate on different db paths. This enables using open source tools such as gtest-parallel to run the tests of a file in parallel.
Example: ``` ~/gtest-parallel/gtest-parallel ./table_test```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4135

Differential Revision: D8846653

Pulled By: maysamyabandeh

fbshipit-source-id: 799bad1abb260e3d346bcb680d2ae207a852ba84
2018-07-13 17:27:39 -07:00
Maysam Yabandeh 0a5b5d88b2 Remove ReadOnly part of PinnableSliceAndMmapReads from Lite (#4070)
Summary:
Lite does not support readonly DBs.
Closes https://github.com/facebook/rocksdb/pull/4070

Differential Revision: D8677858

Pulled By: maysamyabandeh

fbshipit-source-id: 536887d2363ee2f5d8e1ea9f1a511e643a1707fa
2018-06-28 08:42:17 -07:00
Maysam Yabandeh 235ab9dd32 Pin mmap files in ReadOnlyDB (#4053)
Summary:
https://github.com/facebook/rocksdb/pull/3881 fixed a bug where PinnableSlice pin mmap files which could be deleted with background compaction. This is however a non-issue for ReadOnlyDB when there is no compaction running and max_open_files is -1. This patch reenables the pinning feature for that case.
Closes https://github.com/facebook/rocksdb/pull/4053

Differential Revision: D8662546

Pulled By: maysamyabandeh

fbshipit-source-id: 402962602eb0f644e17822748332999c3af029fd
2018-06-27 17:13:34 -07:00
Manuel Ung a16e00b7b9 WriteUnPrepared Txn: Disable seek to snapshot optimization (#3955)
Summary:
This is implemented by extending ReadCallback with another function `MaxUnpreparedSequenceNumber` which returns the largest visible sequence number for the current transaction, if there is uncommitted data written to DB. Otherwise, it returns zero, indicating no uncommitted data.

There are the places where reads had to be modified.
- Get and Seek/Next was just updated to seek to max(snapshot_seq, MaxUnpreparedSequenceNumber()) instead, and iterate until a key was visible.
- Prev did not need need updates since it did not use the Seek to sequence number optimization. Assuming that locks were held when writing unprepared keys, and ValidateSnapshot runs, there should only be committed keys and unprepared keys of the current transaction, all of which are visible. Prev will simply iterate to get the last visible key.
- Reseeking to skip keys optimization was also disabled for write unprepared, since it's possible to hit the max_skip condition even while reseeking. There needs to be some way to resolve infinite looping in this case.
Closes https://github.com/facebook/rocksdb/pull/3955

Differential Revision: D8286688

Pulled By: lth

fbshipit-source-id: 25e42f47fdeb5f7accea0f4fd350ef35198caafe
2018-06-27 12:23:07 -07:00
Andrew Kryczka fea2b1dfb2 Copy Get() result when file reads use mmap
Summary:
For iterator reads, a `SuperVersion` is pinned to preserve a snapshot of SST files, and `Block`s are pinned to allow `key()` and `value()` to return pointers directly into a RocksDB memory region. This works for both non-mmap reads, where the block owns the memory region, and mmap reads, where the file owns the memory region.

For point reads with `PinnableSlice`, only the `Block` object is pinned. This works for non-mmap reads because the block owns the memory region, so even if the file is deleted after compaction, the memory region survives. However, for mmap reads, file deletion causes the memory region to which the `PinnableSlice` refers to be unmapped.   The result is usually a segfault upon accessing the `PinnableSlice`, although sometimes it returned wrong results (I repro'd this a bunch of times with `db_stress`).

This PR copies the value into the `PinnableSlice` when it comes from mmap'd memory. We can tell whether the `Block` owns its memory using `Block::cachable()`, which is unset when reads do not use the provided buffer as is the case with mmap file reads. When that is false we ensure the result of `Get()` is copied.

This feels like a short-term solution as ideally we'd have the `PinnableSlice` pin the mmap'd memory so we can do zero-copy reads. It seemed hard so I chose this approach to fix correctness in the meantime.
Closes https://github.com/facebook/rocksdb/pull/3881

Differential Revision: D8076288

Pulled By: ajkr

fbshipit-source-id: 31d78ec010198723522323dbc6ea325122a46b08
2018-06-01 16:57:58 -07:00
Andrew Kryczka 072ae671a7 Apply use_direct_io_for_flush_and_compaction to writes only
Summary:
Previously `DBOptions::use_direct_io_for_flush_and_compaction=true` combined with `DBOptions::use_direct_reads=false` could cause RocksDB to simultaneously read from two file descriptors for the same file, where background reads used direct I/O and foreground reads used buffered I/O. Our measurements found this mixed-mode I/O negatively impacted foreground read perf, compared to when only buffered I/O was used.

This PR makes the mixed-mode I/O situation impossible by repurposing `DBOptions::use_direct_io_for_flush_and_compaction` to only apply to background writes, and `DBOptions::use_direct_reads` to apply to all reads. There is no risk of direct background direct writes happening simultaneously with buffered reads since we never read from and write to the same file simultaneously.
Closes https://github.com/facebook/rocksdb/pull/3829

Differential Revision: D7915443

Pulled By: ajkr

fbshipit-source-id: 78bcbf276449b7e7766ab6b0db246f789fb1b279
2018-05-09 19:42:58 -07:00
David Lai 3be9b36453 comment unused parameters to turn on -Wunused-parameter flag
Summary:
This PR comments out the rest of the unused arguments which allow us to turn on the -Wunused-parameter flag. This is the second part of a codemod relating to https://github.com/facebook/rocksdb/pull/3557.
Closes https://github.com/facebook/rocksdb/pull/3662

Differential Revision: D7426121

Pulled By: Dayvedde

fbshipit-source-id: 223994923b42bd4953eb016a0129e47560f7e352
2018-04-12 17:59:16 -07:00
Phani Shekhar Mantripragada 446b32cfc3 Support for Column family specific paths.
Summary:
In this change, an option to set different paths for different column families is added.
This option is set via cf_paths setting of ColumnFamilyOptions. This option will work in a similar fashion to db_paths setting. Cf_paths is a vector of Dbpath values which contains a pair of the absolute path and target size. Multiple levels in a Column family can go to different paths if cf_paths has more than one path.
To maintain backward compatibility, if cf_paths is not specified for a column family, db_paths setting will be used. Note that, if db_paths setting is also not specified, RocksDB already has code to use db_name as the only path.

Changes :
1) A new member "cf_paths" is added to ImmutableCfOptions. This is set, based on cf_paths setting of ColumnFamilyOptions and db_paths setting of ImmutableDbOptions.  This member is used to identify the path information whenever files are accessed.
2) Validation checks are added for cf_paths setting based on existing checks for db_paths setting.
3) DestroyDB, PurgeObsoleteFiles etc. are edited to support multiple cf_paths.
4) Unit tests are added appropriately.
Closes https://github.com/facebook/rocksdb/pull/3102

Differential Revision: D6951697

Pulled By: ajkr

fbshipit-source-id: 60d2262862b0a8fd6605b09ccb0da32bb331787d
2018-04-05 19:58:20 -07:00
Dmitri Smirnov c364eb42b5 Windows cumulative patch
Summary:
This patch addressed several issues.
  Portability including db_test std::thread -> port::Thread Cc: @
  and %z to ROCKSDB portable macro. Cc: maysamyabandeh

  Implement Env::AreFilesSame

  Make the implementation of file unique number more robust

  Get rid of C-runtime and go directly to Windows API when dealing
  with file primitives.

  Implement GetSectorSize() and aling unbuffered read on the value if
  available.

  Adjust Windows Logger for the new interface, implement CloseImpl() Cc: anand1976

  Fix test running script issue where $status var was of incorrect scope
  so the failures were swallowed and not reported.

  DestroyDB() creates a logger and opens a LOG file in the directory
  being cleaned up. This holds a lock on the folder and the cleanup is
  prevented. This fails one of the checkpoin tests. We observe the same in production.
  We close the log file in this change.

 Fix DBTest2.ReadAmpBitmapLiveInCacheAfterDBClose failure where the test
 attempts to open a directory with NewRandomAccessFile which does not
 work on Windows.
  Fix DBTest.SoftLimit as it is dependent on thread timing. CC: yiwu-arbug
Closes https://github.com/facebook/rocksdb/pull/3552

Differential Revision: D7156304

Pulled By: siying

fbshipit-source-id: 43db0a757f1dfceffeb2b7988043156639173f5b
2018-03-06 11:57:43 -08:00
Andrew Kryczka 5d68243e61 Comment out unused variables
Summary:
Submitting on behalf of another employee.
Closes https://github.com/facebook/rocksdb/pull/3557

Differential Revision: D7146025

Pulled By: ajkr

fbshipit-source-id: 495ca5db5beec3789e671e26f78170957704e77e
2018-03-05 13:13:41 -08:00
Igor Sugak aba3409740 Back out "[codemod] - comment out unused parameters"
Reviewed By: igorsugak

fbshipit-source-id: 4a93675cc1931089ddd574cacdb15d228b1e5f37
2018-02-22 12:43:17 -08:00
David Lai f4a030ce81 - comment out unused parameters
Reviewed By: everiq, igorsugak

Differential Revision: D7046710

fbshipit-source-id: 8e10b1f1e2aecebbfb229c742e214db887e5a461
2018-02-22 09:44:23 -08:00
Andrew Kryczka ab5ab36ac2 fix DBTest2.ReadAmpBitmapLiveInCacheAfterDBClose file ID support check
Summary:
Updated the test case to handle tmpfs mounted at directories different from "/dev/shm/".
Closes https://github.com/facebook/rocksdb/pull/3440

Differential Revision: D6848213

Pulled By: ajkr

fbshipit-source-id: 465e9dbf0921d0930161f732db6b3766bb030589
2018-01-30 16:50:42 -08:00
Andrew Kryczka 46e599fc6b fix live WALs purged while file deletions disabled
Summary:
When calling `DisableFileDeletions` followed by `GetSortedWalFiles`, we guarantee the files returned by the latter call won't be deleted until after file deletions are re-enabled. However, `GetSortedWalFiles` didn't omit files already planned for deletion via `PurgeObsoleteFiles`, so the guarantee could be broken.

We fix it by making `GetSortedWalFiles` wait for the number of pending purges to hit zero if file deletions are disabled. This condition is eventually met since `PurgeObsoleteFiles` is guaranteed to be called for the existing pending purges, and new purges cannot be scheduled while file deletions are disabled. Once the condition is met, `GetSortedWalFiles` simply returns the content of DB and archive directories, which nobody can delete (except for deletion scheduler, for which I plan to fix this bug later) until deletions are re-enabled.
Closes https://github.com/facebook/rocksdb/pull/3341

Differential Revision: D6681131

Pulled By: ajkr

fbshipit-source-id: 90b1e2f2362ea9ef715623841c0826611a817634
2018-01-17 17:42:04 -08:00
Andrew Kryczka 93f69cb93a use bottommost compression when base level is bottommost
Summary:
The previous compression type selection caused unexpected behavior when the base level was also the bottommost level. The following sequence of events could happen:

- full compaction generates files with `bottommost_compression` type
- now base level is bottommost level since all files are in the same level
- any compaction causes files to be rewritten `compression_per_level` type since bottommost compression didn't apply to base level

I changed the code to make bottommost compression apply to base level.
Closes https://github.com/facebook/rocksdb/pull/3141

Differential Revision: D6264614

Pulled By: ajkr

fbshipit-source-id: d7aaa8675126896684154a1f2c9034d6214fde82
2017-11-09 17:42:00 -08:00