Commit graph

86 commits

Author SHA1 Message Date
Jay Zhuang 69760b4d05 Introduce a global StatsDumpScheduler for stats dumping (#7223)
Summary:
Have a global StatsDumpScheduler for all DB instance stats dumping, including `DumpStats()` and `PersistStats()`. Before this, there're 2 dedicate threads for every DB instance, one for DumpStats() one for PersistStats(), which could create lots of threads if there're hundreds DB instances.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7223

Reviewed By: riversand963

Differential Revision: D23056737

Pulled By: jay-zhuang

fbshipit-source-id: 0faa2311142a73433ebb3317361db7cbf43faeba
2020-08-14 20:12:44 -07:00
Yanqin Jin d758273ceb Get() with timestamp should respect snapshot (#7227)
Summary:
If user-defined timestamp is enabled, current implementation can expose
newer data to queries even if an older sequence number is specified via
read_options.snapshot. This PR makes Get() respect sequence-number-based
snapshot.

Solution is simple. Besides using <ukey, ts, seq> to search the index for the key,
we also verify that the candidate result's seq is smaller than or equal to seq. This
requires passing a seq via `GetContext`, which results in the majority of code
change caused by this PR.

Also added a few unit tests to demonstrate standard visibility during point lookup
and range scan when timestamp and snapshot are both present.

Test plan (devserver):
```
make check
$./db_bench --benchmarks=fillseq,readrandom -cache_size=$[64*1024*1024]
```
Result
this PR: readrandom   :       4.827 micros/op 207180 ops/sec;   22.9 MB/s (1000000 of 1000000 found)
master:  readrandom   :       4.936 micros/op 202610 ops/sec;   22.4 MB/s (1000000 of 1000000 found)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7227

Reviewed By: ltamasi

Differential Revision: D23015242

Pulled By: riversand963

fbshipit-source-id: ea7b85a728654553ba357d2e6a207b5e40f7376a
2020-08-14 19:20:58 -07:00
Akanksha Mahajan 1f9f630b27 Store FileSystemPtr object that contains FileSystem ptr (#7180)
Summary:
As part of the IOTracing project, this PR
    1. Caches "FileSystemPtr" object(wrapper class that returns file system pointer based on tracing enabled) instead of "FileSystem" pointer.
    2. FileSystemPtr object is created using FileSystem pointer and IOTracer
    pointer.
    3. IOTracer shared_ptr is created in DBImpl and it is passed to different classes through constructor.
    4. When tracing is enabled through DB::StartIOTrace, FileSystemPtr
    returns FileSystemTracingWrapper pointer for tracing purpose and when
    it is disabled underlying FileSystem pointer is returned.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7180

Test Plan:
make check -j64
                COMPILE_WITH_TSAN=1 make check -j64

Reviewed By: anand1976

Differential Revision: D22987117

Pulled By: akankshamahajan15

fbshipit-source-id: 6073617e4c2d5bc363914f3a1f55ae3b0a58fbf1
2020-08-12 17:31:23 -07:00
anand76 832b056a30 Enable IO timeouts for iterators (#7161)
Summary:
Introduce io_timeout in ReadOptions and enabled deadline/io_timeout for
Iterators.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7161

Test Plan: New unit tests in db_basic_test

Reviewed By: riversand963

Differential Revision: D22687352

Pulled By: anand1976

fbshipit-source-id: 67bbb0e6d7ae80b256589244468494292538c6ec
2020-08-07 12:01:08 -07:00
Akanksha Mahajan 493f425e77 Add support to start and end IOTracing through DB APIs (#7203)
Summary:
1. Add support to start io tracing through DB::StartIOTrace(Env*, const TraceOptions&, std::unique_ptr<TraceWriter>&&) and end tracing through DB::EndIOTrace(). This doesn't trace DB::Open.

User side code:

//Open DB
DB::Open(options, dbname, &db);

/* Start tracing */
db->StartIOTrace(env, trace_opt, std::move(trace_writer));

/* Perform Operations */

/*End tracing*/
db->EndIOTrace();

2. Fix the build errors for Windows.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7203

Test Plan: make check -j64

Reviewed By: anand1976

Differential Revision: D22901947

Pulled By: akankshamahajan15

fbshipit-source-id: e59c0b785a802168e6f1aa028d99c224a35cb30c
2020-08-04 18:41:45 -07:00
Andrew Kryczka a4a4a2dabd dedup ReadOptions in iterator hierarchy (#7210)
Summary:
Previously, a `ReadOptions` object was stored in every `BlockBasedTableIterator`
and every `LevelIterator`. This redundancy consumes extra memory,
resulting in the `Arena` making more allocations, and iteration
observing worse cache performance.

This PR migrates callers of `NewInternalIterator()` and
`MakeInputIterator()` to provide a `ReadOptions` object guaranteed to
outlive the returned iterator. When the iterator's lifetime will be managed by the
user, this lifetime guarantee is achieved by storing the `ReadOptions`
value in `ArenaWrappedDBIter`. Then, sub-iterators of `NewInternalIterator()` and
`MakeInputIterator()` can hold a reference-to-const `ReadOptions`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7210

Test Plan:
- `make check` under ASAN and valgrind
- benchmark: on a DB with 2 L0 files and 3 L1+ levels, this PR reduced `Arena` allocation 4792 -> 4160 bytes.

Reviewed By: anand1976

Differential Revision: D22861323

Pulled By: ajkr

fbshipit-source-id: 54aebb3e89c872eeab0f5793b4b6e42878d093ce
2020-08-03 15:23:04 -07:00
sdong 9870704420 Fix a minor data race in stats dumping threads initialization (#7151)
Summary:
https://github.com/facebook/rocksdb/pull/7145 creates a minor data race against the stat creation counter. Turn it to atomic.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7151

Test Plan: Run the test.

Reviewed By: ajkr

Differential Revision: D22631014

fbshipit-source-id: c6fb69ac5b9df7139795dacea5ce9fb9fd3278d7
2020-07-20 12:12:43 -07:00
Andrew Kryczka 9a83fd21e6 stagger first DumpMallocStats after opening DB (#7145)
Summary:
Previously when running `db_bench` with large value for `num_multi_dbs` and enabled `Options::dump_malloc_stats`, we would see most CPU spent in jemalloc locking. After this PR that no longer shows up at the top of the profile.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7145

Reviewed By: riversand963

Differential Revision: D22593031

Pulled By: ajkr

fbshipit-source-id: 3b3fc91f93249c6afee53f59f34c487c3fc5add6
2020-07-17 16:13:26 -07:00
Jay Zhuang 00de699096 Replace reinterpret_cast with static_cast_with_check (#7067)
Summary:
Replace `reinterpret_cast` with `static_cast_with_check` for `DBImpl` and `ColumnFamilyHandleImpl`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7067

Reviewed By: siying

Differential Revision: D22361587

Pulled By: jay-zhuang

fbshipit-source-id: dfe9e8f3af39c3d27cc372c55ab9ad905eb0a5a1
2020-07-02 19:25:41 -07:00
Zitan Chen 373d5ac485 BackupEngine verifies table file checksums on creating new backups (#7015)
Summary:
When table file checksums are enabled and stored in the DB manifest by using the RocksDB default crc32c checksum function, BackupEngine will calculate the crc32c checksum of the file to be copied and compare the calculated result with the one stored in the DB manifest before copying the file to the backup directory.

After copying to the backup directory, BackupEngine will verify the checksum of the copied file with the one calculated before copying. This helps detect some rare corruption events such as bit-flips during the copying process.

No verification with checksums in DB manifest will be performed if the table file checksum function is not the RocksDB default crc32c checksum function.

In addition, If `share_table_files` and `share_files_with_checksum` are true, BackupEngine will compare the checksums computed before and after copying of the table files.

Corresponding tests are added.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7015

Test Plan: Passed make check

Reviewed By: pdillinger

Differential Revision: D22165732

Pulled By: gg814

fbshipit-source-id: ee0e8cc397c455eba64545c29380b9d9853588ec
2020-07-02 18:15:12 -07:00
Anand Ananthabhotla 9a5886bd8c Extend Get/MultiGet deadline support to table open (#6982)
Summary:
Current implementation of the ```read_options.deadline``` option only checks the deadline for random file reads during point lookups. This PR extends the checks to file opens, prefetches and preloads as part of table open.

The main changes are in the ```BlockBasedTable```, partitioned index and filter readers, and ```TableCache``` to take ReadOptions as an additional parameter. In ```BlockBasedTable::Open```, in order to retain existing behavior w.r.t checksum verification and block cache usage, we filter out most of the options in ```ReadOptions``` except ```deadline```. However, having the ```ReadOptions``` gives us more flexibility to honor other options like verify_checksums, fill_cache etc. in the future.

Additional changes in callsites due to function signature changes in ```NewTableReader()``` and ```FilePrefetchBuffer```.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6982

Test Plan: Add new unit tests in db_basic_test

Reviewed By: riversand963

Differential Revision: D22219515

Pulled By: anand1976

fbshipit-source-id: 8a3b92f4a889808013838603aa3ca35229cd501b
2020-06-29 14:53:17 -07:00
Zitan Chen be41c61f22 Add a new option for BackupEngine to store table files under shared_checksum using DB session id in the backup filenames (#6997)
Summary:
`BackupableDBOptions::new_naming_for_backup_files` is added. This option is false by default. When it is true, backup table filenames under directory shared_checksum are of the form `<file_number>_<crc32c>_<db_session_id>.sst`.

Note that when this option is true, it comes into effect only when both `share_files_with_checksum` and `share_table_files` are true.

Three new test cases are added.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6997

Test Plan: Passed make check.

Reviewed By: ajkr

Differential Revision: D22098895

Pulled By: gg814

fbshipit-source-id: a1d9145e7fe562d71cde7ac995e17cb24fd42e76
2020-06-24 19:31:25 -07:00
Yanqin Jin e66199d848 First step towards handling MANIFEST write error (#6949)
Summary:
This PR provides preliminary support for handling IO error during MANIFEST write.
File write/sync is not guaranteed to be atomic. If we encounter an IOError while writing/syncing to the MANIFEST file, we cannot be sure about the state of the MANIFEST file. The version edits may or may not have reached the file. During cleanup, if we delete the newly-generated SST files referenced by the pending version edit(s), but the version edit(s) actually are persistent in the MANIFEST, then next recovery attempt will process the version edits(s) and then fail since the SST files have already been deleted.
One approach is to truncate the MANIFEST after write/sync error, so that it is safe to delete the SST files. However, file truncation may not be supported on certain file systems. Therefore, we take the following approach.
If an IOError is detected during MANIFEST write/sync, we disable file deletions for the faulty database. Depending on whether the IOError is retryable (set by underlying file system), either RocksDB or application can call `DB::Resume()`, or simply shutdown and restart. During `Resume()`, RocksDB will try to switch to a new MANIFEST and write all existing in-memory version storage in the new file. If this succeeds, then RocksDB may proceed. If all recovery is completed, then file deletions will be re-enabled.
Note that multiple threads can call `LogAndApply()` at the same time, though only one of them will be going through the process MANIFEST write, possibly batching the version edits of other threads. When the leading MANIFEST writer finishes, all of the MANIFEST writing threads in this batch will have the same IOError. They will all call `ErrorHandler::SetBGError()` in which file deletion will be disabled.

Possible future directions:
- Add an `ErrorContext` structure so that it is easier to pass more info to `ErrorHandler`. Currently, as in this example, a new `BackgroundErrorReason` has to be added.

Test plan (dev server):
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6949

Reviewed By: anand1976

Differential Revision: D22026020

Pulled By: riversand963

fbshipit-source-id: f3c68a2ef45d9b505d0d625c7c5e0c88495b91c8
2020-06-24 19:07:08 -07:00
sdong d6b7b7712f Fix a bug that causes iterator to return wrong result in a rare data race (#6973)
Summary:
The bug fixed in https://github.com/facebook/rocksdb/pull/1816/ is now applicable to iterator too. This was not an issue but https://github.com/facebook/rocksdb/pull/2886 caused the regression. If a put and DB flush happens just between iterator to get latest sequence number and getting super version, empty result for the key or an older value can be returned, which is wrong.
Fix it in the same way as the fix in https://github.com/facebook/rocksdb/issues/1816, that is to get the sequence number after referencing the super version.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6973

Test Plan: Will run stress tests for a while to make sure there is no general regression.

Reviewed By: ajkr

Differential Revision: D22029348

fbshipit-source-id: 94390f93630906796d6e2fec321f44a920953fd1
2020-06-18 10:16:38 -07:00
Zitan Chen 88db97b06d Add a DB Session ID (#6959)
Summary:
Added DB::GetDbSessionId by using the same format and machinery as DB::GetDbIdentity.
The DB Session ID is generated (and therefore, updated) each time a DB object is opened. It is written to the LOG file right after the line of “DB SUMMARY”.
A test for the uniqueness, for different openings and during the same opening, is also added.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6959

Test Plan: Passed make check

Reviewed By: zhichao-cao

Differential Revision: D21951721

Pulled By: gg814

fbshipit-source-id: 958a48a612db49a39998ea703cded45987d3fa8b
2020-06-15 10:47:02 -07:00
Zhichao Cao b3585a11b4 Ingest SST files with checksum information (#6891)
Summary:
Application can ingest SST files with file checksum information, such that during ingestion, DB is able to check data integrity and identify of the SST file. The PR introduces generate_and_verify_file_checksum to IngestExternalFileOption to control if the ingested checksum information should be verified with the generated checksum.

    1. If generate_and_verify_file_checksum options is *FALSE*: *1)* if DB does not enable SST file checksum, the checksum information ingested will be ignored; *2)* if DB enables the SST file checksum and the checksum function name matches the checksum function name in DB, we trust the ingested checksum, store it in Manifest. If the checksum function name does not match, we treat that as an error and fail the IngestExternalFile() call.
    2. If generate_and_verify_file_checksum options is *TRUE*: *1)* if DB does not enable SST file checksum, the checksum information ingested will be ignored; *2)* if DB enable the SST file checksum, we will use the checksum generator from DB to calculate the checksum for each ingested SST files after they are copied or moved. Then, compare the checksum results with the ingested checksum information: _A)_ if the checksum function name does not match, _verification always report true_ and we store the DB generated checksum information in Manifest. _B)_ if the checksum function name mach, and checksum match, ingestion continues and stores the checksum information in the Manifest. Otherwise, terminate file ingestion and report file corruption.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6891

Test Plan: added unit test, pass make asan_check

Reviewed By: pdillinger

Differential Revision: D21935988

Pulled By: zhichao-cao

fbshipit-source-id: 7b55f486632db467e76d72602218d0658aa7f6ed
2020-06-11 14:27:36 -07:00
Akanksha Mahajan bcefc59e9f Allow MultiGet users to limit cumulative value size (#6826)
Summary:
1. Add a value_size in read options which limits the cumulative value size of keys read in batches. Once the size exceeds read_options.value_size, all the remaining keys are returned with status Abort without further fetching any key.
2. Add a unit test case MultiGetBatchedValueSizeSimple the reads keys from memory and sst files.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6826

Test Plan:
1. make check -j64
	   2. Add a new unit test case

Reviewed By: anand1976

Differential Revision: D21471483

Pulled By: akankshamahajan15

fbshipit-source-id: dea51b8e76d5d1df38ece8cdb29933b1d798b900
2020-05-27 13:07:14 -07:00
anand76 ab13d43e1d Pass a timeout to FileSystem for random reads (#6751)
Summary:
Calculate ```IOOptions::timeout``` using ```ReadOptions::deadline``` and pass it to ```FileSystem::Read/FileSystem::MultiRead```. This allows us to impose a tighter bound on the time taken by Get/MultiGet on FileSystem/Envs that support IO timeouts. Even on those that don't support, check in ```RandomAccessFileReader::Read``` and ```MultiRead``` and return ```Status::TimedOut()``` if the deadline is exceeded.

For now, TableReader creation, which might do file opens and reads, are not covered. It will be implemented in another PR.

Tests:
Update existing unit tests to verify the correct timeout value is being passed
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6751

Reviewed By: riversand963

Differential Revision: D21285631

Pulled By: anand1976

fbshipit-source-id: d89af843e5a91ece866e87aa29438b52a65a8567
2020-04-30 14:50:39 -07:00
Derrick Pallas 5272305437 Fix FilterBench when RTTI=0 (#6732)
Summary:
The dynamic_cast in the filter benchmark causes release mode to fail due to
no-rtti.  Replace with static_cast_with_check.

Signed-off-by: Derrick Pallas <derrick@pallas.us>

Addition by peterd: Remove unnecessary 2nd template arg on all static_cast_with_check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6732

Reviewed By: ltamasi

Differential Revision: D21304260

Pulled By: pdillinger

fbshipit-source-id: 6e8eb437c4ca5a16dbbfa4053d67c4ad55f1608c
2020-04-29 13:09:23 -07:00
Yanqin Jin d4398e08fc Fix timestamp support for MultiGet (#6748)
Summary:
1. Avoid nullptr dereference when passing timestamp to KeyContext creation.
2. Construct LookupKey correctly with timestamp when creating MultiGetContext.
3. Compare without timestamp when sorting KeyContexts.

Fixes https://github.com/facebook/rocksdb/issues/6745

Test plan (dev server):
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6748

Reviewed By: pdillinger

Differential Revision: D21258691

Pulled By: riversand963

fbshipit-source-id: 44e65b759c18b9986947783edf03be4f890bb004
2020-04-27 22:49:56 -07:00
anand76 c1ccd6b6af Implement deadline support for MultiGet (#6710)
Summary:
Initial implementation of ReadOptions.deadline for MultiGet. If the request takes longer than the deadline, the keys not yet found will be returned with Status::TimedOut(). This
implementation enforces the deadline in DBImpl, which is fairly high
level. Its best effort and may not check the deadline after every key
lookup, but may do so after a batch of keys.

In subsequent stages, we will extend this to passing a timeout down to the FileSystem.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6710

Test Plan: Add new unit tests

Reviewed By: riversand963

Differential Revision: D21149158

Pulled By: anand1976

fbshipit-source-id: 9f44eecffeb40873f5034ed59a66d21f9f88879e
2020-04-21 14:51:51 -07:00
Akanksha Mahajan 03a1d95db0 Set max_background_flushes dynamically (#6701)
Summary:
1. Add changes so that max_background_flushes can be set dynamically.
                   2. Add a testcase DBOptionsTest.SetBackgroundFlushThreads which set the
                        max_background_flushes dynamically using SetDBOptions.

TestPlan:  1. make -j64 check
                  2. Using new testcase DBOptionsTest.SetBackgroundFlushThreads
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6701

Reviewed By: ajkr

Differential Revision: D21028010

Pulled By: akankshamahajan15

fbshipit-source-id: 5f949e4a8fd3c32537b637947b7ee09a69cfc7c1
2020-04-20 16:19:02 -07:00
Mike Kolupaev e45673dece Properly report IO errors when IndexType::kBinarySearchWithFirstKey is used (#6621)
Summary:
Context: Index type `kBinarySearchWithFirstKey` added the ability for sst file iterator to sometimes report a key from index without reading the corresponding data block. This is useful when sst blocks are cut at some meaningful boundaries (e.g. one block per key prefix), and many seeks land between blocks (e.g. for each prefix, the ranges of keys in different sst files are nearly disjoint, so a typical seek needs to read a data block from only one file even if all files have the prefix). But this added a new error condition, which rocksdb code was really not equipped to deal with: `InternalIterator::value()` may fail with an IO error or Status::Incomplete, but it's just a method returning a Slice, with no way to report error instead. Before this PR, this type of error wasn't handled at all (an empty slice was returned), and kBinarySearchWithFirstKey implementation was considered a prototype.

Now that we (LogDevice) have experimented with kBinarySearchWithFirstKey for a while and confirmed that it's really useful, this PR is adding the missing error handling.

It's a pretty inconvenient situation implementation-wise. The error needs to be reported from InternalIterator when trying to access value. But there are ~700 call sites of `InternalIterator::value()`, most of which either can't hit the error condition (because the iterator is reading from memtable or from index or something) or wouldn't benefit from the deferred loading of the value (e.g. compaction iterator that reads all values anyway). Adding error handling to all these call sites would needlessly bloat the code. So instead I made the deferred value loading optional: only the call sites that may use deferred loading have to call the new method `PrepareValue()` before calling `value()`. The feature is enabled with a new bool argument `allow_unprepared_value` to a bunch of methods that create iterators (it wouldn't make sense to put it in ReadOptions because it's completely internal to iterators, with virtually no user-visible effect). Lmk if you have better ideas.

Note that the deferred value loading only happens for *internal* iterators. The user-visible iterator (DBIter) always prepares the value before returning from Seek/Next/etc. We could go further and add an API to defer that value loading too, but that's most likely not useful for LogDevice, so it doesn't seem worth the complexity for now.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6621

Test Plan: make -j5 check . Will also deploy to some logdevice test clusters and look at stats.

Reviewed By: siying

Differential Revision: D20786930

Pulled By: al13n321

fbshipit-source-id: 6da77d918bad3780522e918f17f4d5513d3e99ee
2020-04-15 17:40:44 -07:00
Cheng Chang ee50b8d499 Be able to decrease background thread's CPU priority when creating database backup (#6602)
Summary:
When creating a database backup, the background threads will not only consume IO resources by copying files, but also consuming CPU such as by computing checksums. During peak times, the CPU consumption by the background threads might affect online queries.

This PR makes it possible to decrease CPU priority of these threads when creating a new backup.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6602

Test Plan: make check

Reviewed By: siying, zhichao-cao

Differential Revision: D20683216

Pulled By: cheng-chang

fbshipit-source-id: 9978b9ed9488e8ce135e90ca083e5b4b7221fd84
2020-03-28 19:07:25 -07:00
Zhichao Cao 4246888101 Pass IOStatus to write path and set retryable IO Error as hard error in BG jobs (#6487)
Summary:
In the current code base, we use Status to get and store the returned status from the call. Specifically, for IO related functions, the current Status cannot reflect the IO Error details such as error scope, error retryable attribute, and others. With the implementation of https://github.com/facebook/rocksdb/issues/5761, we have the new Wrapper for IO, which returns IOStatus instead of Status. However, the IOStatus is purged at the lower level of write path and transferred to Status.

The first job of this PR is to pass the IOStatus to the write path (flush, WAL write, and Compaction). The second job is to identify the Retryable IO Error as HardError, and set the bg_error_ as HardError. In this case, the DB Instance becomes read only. User is informed of the Status and need to take actions to deal with it (e.g., call db->Resume()).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6487

Test Plan: Added the testing case to error_handler_fs_test. Pass make asan_check

Reviewed By: anand1976

Differential Revision: D20685017

Pulled By: zhichao-cao

fbshipit-source-id: ff85f042896243abcd6ef37877834e26f36b6eb0
2020-03-27 16:04:43 -07:00
Huisheng Liu a6ce5c823b multiget support for timestamps (#6483)
Summary:
Add timestamp support for MultiGet().
timestamp from readoptions is honored, and timestamps can be returned along with values.

MultiReadRandom perf test (10 minutes) on the same development machine ram drive with the same DB data shows no regression (within marge of error). The test is adapted from https://github.com/facebook/rocksdb/wiki/RocksDB-In-Memory-Workload-Performance-Benchmarks.
base line (commit 17bef7d3a):
  multireadrandom :     104.173 micros/op 307167 ops/sec; (5462999 of 5462999 found)
This PR:
  multireadrandom :     104.199 micros/op 307095 ops/sec; (5307999 of 5307999 found)

.\db_bench --db=r:\rocksdb.github --num_levels=6 --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 --cache_size=2147483648 --cache_numshardbits=6 --compression_type=none --compression_ratio=1 --min_level_to_compress=-1 --disable_seek_compaction=1 --hard_rate_limit=2 --write_buffer_size=134217728 --max_write_buffer_number=2 --level0_file_num_compaction_trigger=8 --target_file_size_base=134217728 --max_bytes_for_level_base=1073741824 --disable_wal=0 --wal_dir=r:\rocksdb.github\WAL_LOG --sync=0 --verify_checksum=1 --statistics=0 --stats_per_interval=0 --stats_interval=1048576 --histogram=0 --use_plain_table=1 --open_files=-1 --memtablerep=prefix_hash --bloom_bits=10 --bloom_locality=1 --duration=600 --benchmarks=multireadrandom --use_existing_db=1 --num=25000000 --threads=32 --allow_concurrent_memtable_write=0
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6483

Reviewed By: anand1976

Differential Revision: D20498373

Pulled By: riversand963

fbshipit-source-id: 8505f22bc40fd791bc7dd05e48d7e67c91edb627
2020-03-24 11:24:09 -07:00
anand76 a9d168cfd7 Simplify migration to FileSystem API (#6552)
Summary:
The current Env/FileSystem API separation has a couple of issues -
1. It requires the user to specify 2 options - ```Options::env``` and ```Options::file_system``` - which means they have to make code changes to benefit from the new APIs. Furthermore, there is a risk of accessing the same APIs in two different ways, through Env in the old way and through FileSystem in the new way. The two may not always match, for example, if env is ```PosixEnv``` and FileSystem is a custom implementation. Any stray RocksDB calls to env will use the ```PosixEnv``` implementation rather than the file_system implementation.
2. There needs to be a simple way for the FileSystem developer to instantiate an Env for backward compatibility purposes.

This PR solves the above issues and simplifies the migration in the following ways -
1. Embed a shared_ptr to the ```FileSystem``` in the ```Env```, and remove ```Options::file_system``` as a configurable option. This way, no code changes will be required in application code to benefit from the new API. The default Env constructor uses a ```LegacyFileSystemWrapper``` as the embedded ```FileSystem```.
1a. - This also makes it more robust by ensuring that even if RocksDB
  has some stray calls to Env APIs rather than FileSystem, they will go
  through the same object and thus there is no risk of getting out of
  sync.
2. Provide a ```NewCompositeEnv()``` API that can be used to construct a
PosixEnv with a custom FileSystem implementation. This eliminates an
indirection to call Env APIs, and relieves the FileSystem developer of
the burden of having to implement wrappers for the Env APIs.
3. Add a couple of missing FileSystem APIs - ```SanitizeEnvOptions()``` and
```NewLogger()```

Tests:
1. New unit tests
2. make check and make asan_check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6552

Reviewed By: riversand963

Differential Revision: D20592038

Pulled By: anand1976

fbshipit-source-id: c3801ad4153f96d21d5a3ae26c92ba454d1bf1f7
2020-03-23 21:54:21 -07:00
Cheng Chang 2d9efc9ab2 Cache result of GetLogicalBufferSize in Linux (#6457)
Summary:
In Linux, when reopening DB with many SST files, profiling shows that 100% system cpu time spent for a couple of seconds for `GetLogicalBufferSize`. This slows down MyRocks' recovery time when site is down.

This PR introduces two new APIs:
1. `Env::RegisterDbPaths` and `Env::UnregisterDbPaths` lets `DB` tell the env when it starts or stops using its database directories . The `PosixFileSystem` takes this opportunity to set up a cache from database directories to the corresponding logical block sizes.
2. `LogicalBlockSizeCache` is defined only for OS_LINUX to cache the logical block sizes.

Other modifications:
1. rename `logical buffer size` to `logical block size` to be consistent with Linux terms.
2. declare `GetLogicalBlockSize` in `PosixHelper` to expose it to `PosixFileSystem`.
3. change the functions `IOError` and `IOStatus` in `env/io_posix.h` to have external linkage since they are used in other translation units too.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6457

Test Plan:
1. A new unit test is added for `LogicalBlockSizeCache` in `env/io_posix_test.cc`.
2. A new integration test is added for `DB` operations related to the cache in `db/db_logical_block_size_cache_test.cc`.

`make check`

Differential Revision: D20131243

Pulled By: cheng-chang

fbshipit-source-id: 3077c50f8065c0bffb544d8f49fb10bba9408d04
2020-03-11 18:40:05 -07:00
sdong 17bef7d3a8 Fix data race of GetCreationTimeOfOldestFile() (#6473)
Summary:
When DBImpl::GetCreationTimeOfOldestFile() calls Version::GetCreationTimeOfOldestFile(), the version is not directly or indirectly referenced, so an event like compaction can race with the operation and cause DBImpl::GetCreationTimeOfOldestFile() to access delocated data. This was caught by an ASAN run:

==268==ERROR: AddressSanitizer: heap-use-after-free on address 0x612000b7d198 at pc 0x000018332913 bp 0x7f391510d310 sp 0x7f391510d308
READ of size 8 at 0x612000b7d198 thread T845 (store_load-33)
SCARINESS: 51 (8-byte-read-heap-use-after-free)
    #0 0x18332912 in rocksdb::Version::GetCreationTimeOfOldestFile(unsigned long*) rocksdb/src/db/version_set.cc:1488
    https://github.com/facebook/rocksdb/issues/1 0x1803ddaa in rocksdb::DBImpl::GetCreationTimeOfOldestFile(unsigned long*) rocksdb/src/db/db_impl/db_impl.cc:4499
    https://github.com/facebook/rocksdb/issues/2 0xe24ca09 in rocksdb::StackableDB::GetCreationTimeOfOldestFile(unsigned long*) rocksdb/utilities/stackable_db.h:392
    ......
0x612000b7d198 is located 216 bytes inside of 296-byte region [0x612000b7d0c0,0x612000b7d1e8)
freed by thread T28 here:
    ......
    https://github.com/facebook/rocksdb/issues/5 0x1832c73f in std::vector<rocksdb::FileMetaData*, std::allocator<rocksdb::FileMetaData*> >::~vector() third-party-buck/platform007/build/libgcc/include/c++/trunk/bits/stl_vector.h:435
    https://github.com/facebook/rocksdb/issues/6 0x1832c73f in rocksdb::VersionStorageInfo::~VersionStorageInfo() rocksdb/src/db/version_set.cc:734
    https://github.com/facebook/rocksdb/issues/7 0x1832cf42 in rocksdb::Version::~Version() rocksdb/src/db/version_set.cc:758
    https://github.com/facebook/rocksdb/issues/8 0x9d1bb5 in rocksdb::Version::Unref() rocksdb/src/db/version_set.cc:2869
    https://github.com/facebook/rocksdb/issues/9 0x183e7631 in rocksdb::Compaction::~Compaction() rocksdb/src/db/compaction/compaction.cc:275
    https://github.com/facebook/rocksdb/issues/10 0x9e6de6 in std::default_delete<rocksdb::Compaction>::operator()(rocksdb::Compaction*) const third-party-buck/platform007/build/libgcc/include/c++/trunk/bits/unique_ptr.h:78
    https://github.com/facebook/rocksdb/issues/11 0x9e6de6 in std::unique_ptr<rocksdb::Compaction, std::default_delete<rocksdb::Compaction> >::reset(rocksdb::Compaction*) third-party-buck/platform007/build/libgcc/include/c++/trunk/bits/unique_ptr.h:376
    https://github.com/facebook/rocksdb/issues/12 0x9e6de6 in rocksdb::DBImpl::BackgroundCompaction(bool*, rocksdb::JobContext*, rocksdb::LogBuffer*, rocksdb::DBImpl::PrepickedCompaction*, rocksdb::Env::Priority) rocksdb/src/db/db_impl/db_impl_compaction_flush.cc:2826
    https://github.com/facebook/rocksdb/issues/13 0x9ac3b8 in rocksdb::DBImpl::BackgroundCallCompaction(rocksdb::DBImpl::PrepickedCompaction*, rocksdb::Env::Priority) rocksdb/src/db/db_impl/db_impl_compaction_flush.cc:2320
    https://github.com/facebook/rocksdb/issues/14 0x9abff7 in rocksdb::DBImpl::BGWorkCompaction(void*) rocksdb/src/db/db_impl/db_impl_compaction_flush.cc:2096
    ......

Fix the issue by reference the super version and use the referenced version from it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6473

Test Plan: Run ASAN for all existing tests.

Differential Revision: D20196416

fbshipit-source-id: 5f4a7918110fc7b8dd7841932d376bc9d1e59d6f
2020-03-02 16:37:01 -08:00
Zhichao Cao 8d73137ae8 Replace Directory with FSDirectory in DB (#6468)
Summary:
In the current code base, we can use Directory from Env to manage directory (e.g, Fsync()). The PR https://github.com/facebook/rocksdb/issues/5761  introduce the File System as a new Env API. So we further replace the Directory class in DB with FSDirectory such that we can have more IO information from IOStatus returned by FSDirectory.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6468

Test Plan: pass make asan_check

Differential Revision: D20195261

Pulled By: zhichao-cao

fbshipit-source-id: 93962cb9436852bfcfb76e086d9e7babd461cbe1
2020-03-02 16:16:26 -08:00
Huisheng Liu 904a60ff63 return timestamp from get (#6409)
Summary:
Added new Get() methods that return timestamp. Dummy implementation is given so that classes derived from DB don't need to be touched to provide their implementation. MultiGet is not included.

ReadRandom perf test (10 minutes) on the same development machine ram drive with the same DB data shows no regression (within marge of error). The test is adapted from https://github.com/facebook/rocksdb/wiki/RocksDB-In-Memory-Workload-Performance-Benchmarks.
    base line (commit 72ee067b9):
        101.712 micros/op 314602 ops/sec;   36.0 MB/s (5658999 of 5658999 found)
    This PR:
        100.288 micros/op 319071 ops/sec;   36.5 MB/s (5674999 of 5674999 found)

./db_bench --db=r:\rocksdb.github --num_levels=6 --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 --cache_size=2147483648 --cache_numshardbits=6 --compression_type=none --compression_ratio=1 --min_level_to_compress=-1 --disable_seek_compaction=1 --hard_rate_limit=2 --write_buffer_size=134217728 --max_write_buffer_number=2 --level0_file_num_compaction_trigger=8 --target_file_size_base=134217728 --max_bytes_for_level_base=1073741824 --disable_wal=0 --wal_dir=r:\rocksdb.github\WAL_LOG --sync=0 --verify_checksum=1 --delete_obsolete_files_period_micros=314572800 --max_background_compactions=4 --max_background_flushes=0 --level0_slowdown_writes_trigger=16 --level0_stop_writes_trigger=24 --statistics=0 --stats_per_interval=0 --stats_interval=1048576 --histogram=0 --use_plain_table=1 --open_files=-1 --mmap_read=1 --mmap_write=0 --memtablerep=prefix_hash --bloom_bits=10 --bloom_locality=1 --duration=600 --benchmarks=readrandom --use_existing_db=1 --num=25000000 --threads=32
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6409

Differential Revision: D20200086

Pulled By: riversand963

fbshipit-source-id: 490edd74d924f62bd8ae9c29c2a6bbbb8410ca50
2020-03-02 16:01:00 -08:00
Yanqin Jin 890d87fadc Some minor fix-ups (#6440)
Summary:
Cleanup some code without any real change in functionality.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6440

Differential Revision: D20015891

Pulled By: riversand963

fbshipit-source-id: 33e18754b0f002006a6d4805e9aaf84c0c8ad25a
2020-02-21 15:09:56 -08:00
sdong fdf882ded2 Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433)
Summary:
When dynamically linking two binaries together, different builds of RocksDB from two sources might cause errors. To provide a tool for user to solve the problem, the RocksDB namespace is changed to a flag which can be overridden in build time.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6433

Test Plan: Build release, all and jtest. Try to build with ROCKSDB_NAMESPACE with another flag.

Differential Revision: D19977691

fbshipit-source-id: aa7f2d0972e1c31d75339ac48478f34f6cfcfb3e
2020-02-20 12:09:57 -08:00
Huisheng Liu 5138764eb5 Fix destroydb (#6308)
Summary:
It's observed on Windows DestroyDB failed to remove the log file because the logger is still alive in sst file manager and holding a handle to the log file. This fix makes sure the logger is released before attempt to clear the database directory.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6308

Differential Revision: D19818829

Pulled By: riversand963

fbshipit-source-id: 54c3e6859aadaaba4a49b3e851b73dc35ec7dc6a
2020-02-13 11:21:27 -08:00
Mike Kolupaev 637e64b9ac Add an option to prevent DB::Open() from querying sizes of all sst files (#6353)
Summary:
When paranoid_checks is on, DBImpl::CheckConsistency() iterates over all sst files and calls Env::GetFileSize() for each of them. As far as I could understand, this is pretty arbitrary and doesn't affect correctness - if filesystem doesn't corrupt fsynced files, the file sizes will always match; if it does, it may as well corrupt contents as well as sizes, and rocksdb doesn't check contents on open.

If there are thousands of sst files, getting all their sizes takes a while. If, on top of that, Env is overridden to use some remote storage instead of local filesystem, it can be *really* slow and overload the remote storage service. This PR adds an option to not do GetFileSize(); instead it does GetChildren() for parent directory to check that all the expected sst files are at least present, but doesn't check their sizes.

We can't just disable paranoid_checks instead because paranoid_checks do a few other important things: make the DB read-only on write errors, print error messages on read errors, etc.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6353

Test Plan: ran the added sanity check unit test. Will try it out in a LogDevice test cluster where the GetFileSize() calls are causing a lot of trouble.

Differential Revision: D19656425

Pulled By: al13n321

fbshipit-source-id: c2c421b367633033760d1f56747bad206d1fbf82
2020-02-04 01:27:26 -08:00
sdong f195d8d523 Use ReadFileToString() to get content from IDENTITY file (#6365)
Summary:
Right now when reading IDENTITY file, we use a very similar logic as ReadFileToString() while it does an extra file size check, which may be expensive in some file systems. There is no reason to duplicate the logic. Use ReadFileToString() instead.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6365

Test Plan: RUn all existing tests.

Differential Revision: D19709399

fbshipit-source-id: 3bac31f3b2471f98a0d2694278b41e9cd34040fe
2020-02-03 17:40:49 -08:00
sdong 36c504be17 Avoid create directory for every column families (#6358)
Summary:
A relatively recent regression causes for every CF, create and open directory is called for the DB directory, unless CF has a private directory. This doesn't scale well with large number of column families.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6358

Test Plan: Run all existing tests and see it pass. strace with db_bench --num_column_families and observe it doesn't open directory for number of column families.

Differential Revision: D19675141

fbshipit-source-id: da01d9216f1dae3f03d4064fbd88ce71245bd9be
2020-02-03 14:13:39 -08:00
Levi Tamasi 73f65b457e Adjust thread pool sizes when setting max_background_jobs dynamically (#6300)
Summary:
https://github.com/facebook/rocksdb/pull/2205 introduced a new
configuration option called `max_background_jobs`, superseding the
earlier options `max_background_flushes` and
`max_background_compactions`. However, unlike
`max_background_compactions`, setting `max_background_jobs` dynamically
through the `SetDBOptions` interface does not adjust the size of the
thread pools (see https://github.com/facebook/rocksdb/issues/6298). The
patch fixes this.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6300

Test Plan: Extended unit test.

Differential Revision: D19430899

Pulled By: ltamasi

fbshipit-source-id: 704006605b3c13c3d1b997ccc0831ee369721074
2020-01-16 14:35:10 -08:00
Mike Kolupaev ce63eda6f0 Fix use-after-free and double-deleting files in BackgroundCallPurge() (#6193)
Summary:
The bad code was:

```
mutex.Lock(); // `mutex` protects `container`
for (auto& x : container) {
  mutex.Unlock();
  // do stuff to x
  mutex.Lock();
}
```

It's incorrect because both `x` and the iterator may become invalid if another thread modifies the container while this thread is not holding the mutex.

Broken by https://github.com/facebook/rocksdb/pull/5796 - it replaced a `while (!container.empty())` loop with a `for (auto x : container)`.

(RocksDB code does a lot of such unlocking+re-locking of mutexes, and this type of bugs comes up a lot :/ )
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6193

Test Plan: Ran some logdevice integration tests that were crashing without this fix.

Differential Revision: D19116874

Pulled By: al13n321

fbshipit-source-id: 9672bc4227c1b68f46f7436db2b96811adb8c703
2019-12-17 20:08:56 -08:00
解轶伦 39fcaf8246 delete superversions in BackgroundCallPurge (#6146)
Summary:
I found that CleanupSuperVersion() may block Get() for 30ms+ (per MemTable is 256MB).

Then I found "delete sv" in ~SuperVersion() takes the time.

The backtrace looks like this

DBImpl::GetImpl() -> DBImpl::ReturnAndCleanupSuperVersion() ->
DBImpl::CleanupSuperVersion() : delete sv; -> ~SuperVersion()

I think it's better to delete in a background thread,  please review it。
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6146

Differential Revision: D18972066

fbshipit-source-id: 0f7b0b70b9bb1e27ad6fc1c8a408fbbf237ae08c
2019-12-17 13:22:57 -08:00
anand76 afa2420c2b Introduce a new storage specific Env API (#5761)
Summary:
The current Env API encompasses both storage/file operations, as well as OS related operations. Most of the APIs return a Status, which does not have enough metadata about an error, such as whether its retry-able or not, scope (i.e fault domain) of the error etc., that may be required in order to properly handle a storage error. The file APIs also do not provide enough control over the IO SLA, such as timeout, prioritization, hinting about placement and redundancy etc.

This PR separates out the file/storage APIs from Env into a new FileSystem class. The APIs are updated to return an IOStatus with metadata about the error, as well as to take an IOOptions structure as input in order to allow more control over the IO.

The user can set both ```options.env``` and ```options.file_system``` to specify that RocksDB should use the former for OS related operations and the latter for storage operations. Internally, a ```CompositeEnvWrapper``` has been introduced that inherits from ```Env``` and redirects individual methods to either an ```Env``` implementation or the ```FileSystem``` as appropriate. When options are sanitized during ```DB::Open```, ```options.env``` is replaced with a newly allocated ```CompositeEnvWrapper``` instance if both env and file_system have been specified. This way, the rest of the RocksDB code can continue to function as before.

This PR also ports PosixEnv to the new API by splitting it into two - PosixEnv and PosixFileSystem. PosixEnv is defined as a sub-class of CompositeEnvWrapper, and threading/time functions are overridden with Posix specific implementations in order to avoid an extra level of indirection.

The ```CompositeEnvWrapper``` translates ```IOStatus``` return code to ```Status```, and sets the severity to ```kSoftError``` if the io_status is retryable. The error handling code in RocksDB can then recover the DB automatically.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5761

Differential Revision: D18868376

Pulled By: anand1976

fbshipit-source-id: 39efe18a162ea746fabac6360ff529baba48486f
2019-12-13 14:48:41 -08:00
Jermy Li c2029f9716 Support concurrent CF iteration and drop (#6147)
Summary:
It's easy to cause coredump when closing ColumnFamilyHandle with unreleased iterators, especially iterators release is controlled by java GC when using JNI.

This patch fixed concurrent CF iteration and drop, we let iterators(actually SuperVersion) hold a ColumnFamilyData reference to prevent the CF from being released too early.

fixed https://github.com/facebook/rocksdb/issues/5982
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6147

Differential Revision: D18926378

fbshipit-source-id: 1dff6d068c603d012b81446812368bfee95a5e15
2019-12-12 19:04:48 -08:00
Connor a844591201 wait pending memtable writes on file ingestion or compact range (#6113)
Summary:
**Summary:**
This PR fixes two unordered_write related issues:
- ingestion job may skip the necessary memtable flush https://github.com/facebook/rocksdb/issues/6026
- compact range may cause memtable is flushed before pending unordered write finished
    1. `CompactRange` triggers memtable flush but doesn't wait for pending-writes
    2.  there are some pending writes but memtable is already flushed
    3.  the memtable related WAL is removed( note that the pending-writes were recorded in that WAL).
    4.  pending-writes write to newer created memtable
    5. there is a restart
    6. missing the previous pending-writes because WAL is removed but they aren't included in SST.

**How to solve:**
- Wait pending memtable writes before ingestion job check memtable key range
- Wait pending memtable writes before flush memtable.
**Note that: `CompactRange` calls `RangesOverlapWithMemtables` too without waiting for pending waits, but I'm not sure whether it affects the correctness.**

**Test Plan:**
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6113

Differential Revision: D18895674

Pulled By: maysamyabandeh

fbshipit-source-id: da22b4476fc7e06c176020e7cc171eb78189ecaf
2019-12-12 14:08:02 -08:00
Yi Wu 05a86318a7 Remove unused low_pri_write_rate_limiter_ (#6068)
Summary:
`low_pri_write_rate_limiter_` is not being used. Removing. `WriteController` has an internal low_pri rate limiter which is the real rate limiter for low-pri writes.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6068

Test Plan: make

Differential Revision: D18664120

fbshipit-source-id: dfe3e4de033cf3522b67781b383aad7d0936034c
2019-12-11 10:28:33 -08:00
Yanqin Jin 0ce0edbe12 Fix a data race between GetColumnFamilyMetaData and MarkFilesBeingCompacted (#6056)
Summary:
Use db mutex to protect the execution of Version::GetColumnFamilyMetaData()
called in DBImpl::GetColumnFamilyMetaData().
Without mutex, GetColumnFamilyMetaData() races with MarkFilesBeingCompacted()
for access to FileMetaData::being_compacted.
Other than mutex, there are several more alternatives.

- Make FileMetaData::being_compacted an atomic variable. This will make
  FileMetaData non-copy-able.

- Separate being_compacted from FileMetaData. This requires re-organizing data
  structures that are already used in many places.

Test Plan (dev server):
```
make check
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6056

Differential Revision: D18620488

Pulled By: riversand963

fbshipit-source-id: 87f89660b5d5e2ab4ef7962b7b2a7d00e346aa3b
2019-11-20 16:36:29 -08:00
sdong 27ec3b3466 Sanitize input in DB::MultiGet() API (#6054)
Summary:
The new DB::MultiGet() doesn't validate input for num_keys > 1 and GCC-9 complains about it. Fix it by directly return when num_keys == 0
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6054

Test Plan: Build with GCC-9 and see it passes.

Differential Revision: D18608958

fbshipit-source-id: 1c279aff3c7fe6e9d5a6d085ed02550ecea4fdb2
2019-11-20 10:38:01 -08:00
anand76 6c7b1a0cc7 Batched MultiGet API for multiple column families (#5816)
Summary:
Add a new API that allows a user to call MultiGet specifying multiple keys belonging to different column families. This is mainly useful for users who want to do a consistent read of keys across column families, with the added performance benefits of batching and returning values using PinnableSlice.

As part of this change, the code in the original multi-column family MultiGet for acquiring the super versions has been refactored into a separate function that can be used by both, the batching and the non-batching versions of MultiGet.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5816

Test Plan:
make check
make asan_check
asan_crash_test

Differential Revision: D18408676

Pulled By: anand1976

fbshipit-source-id: 933e7bec91dd70e7b633be4ff623a1116cc28c8d
2019-11-12 13:52:55 -08:00
Vijay Nadimpalli ec880436c1 API to get file_creation_time of the oldest file in the DB (#5948)
Summary:
Adding a new API to db.h that allows users to get file_creation_time of the oldest file in the DB.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5948

Test Plan: Added unit test.

Differential Revision: D18056151

Pulled By: vjnadimpalli

fbshipit-source-id: 448ec9d34cb6772e1e5a62db399ace00dcbfbb5d
2019-10-25 11:53:57 -07:00
Vijay Nadimpalli 4c49e38f15 MultiGet batching in memtable (#5818)
Summary:
RocksDB has a MultiGet() API that implements batched key lookup for higher performance (https://github.com/facebook/rocksdb/blob/master/include/rocksdb/db.h#L468). Currently, batching is implemented in BlockBasedTableReader::MultiGet() for SST file lookups. One of the ways it improves performance is by pipelining bloom filter lookups (by prefetching required cachelines for all the keys in the batch, and then doing the probe) and thus hiding the cache miss latency. The same concept can be extended to the memtable as well. This PR involves implementing a pipelined bloom filter lookup in DynamicBloom, and implementing MemTable::MultiGet() that can leverage it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5818

Test Plan:
Existing tests

Performance Test:
Ran the below command which fills up the memtable and makes sure there are no flushes and then call multiget. Ran it on master and on the new change and see atleast 1% performance improvement across all the test runs I did. Sometimes the improvement was upto 5%.

TEST_TMPDIR=/data/users/$USER/benchmarks/feature/ numactl -C 10 ./db_bench -benchmarks="fillseq,multireadrandom" -num=600000 -compression_type="none" -level_compaction_dynamic_level_bytes -write_buffer_size=200000000 -target_file_size_base=200000000 -max_bytes_for_level_base=16777216 -reads=90000 -threads=1 -compression_type=none -cache_size=4194304000 -batch_size=32 -disable_auto_compactions=true -bloom_bits=10 -cache_index_and_filter_blocks=true -pin_l0_filter_and_index_blocks_in_cache=true -multiread_batched=true -multiread_stride=4 -statistics -memtable_whole_key_filtering=true -memtable_bloom_size_ratio=10

Differential Revision: D17578869

Pulled By: vjnadimpalli

fbshipit-source-id: 23dc651d9bf49db11d22375bf435708875a1f192
2019-10-10 09:39:39 -07:00
Tomas Kolda e3a93c9ee1 Fix crash when background task fails (#5879)
Summary:
Fixing crash. Full story in issue: https://github.com/facebook/rocksdb/issues/5878
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5879

Differential Revision: D17812299

Pulled By: anand1976

fbshipit-source-id: 14e5a4fc502ade974583da9692d0ed6e5014613a
2019-10-08 14:20:01 -07:00