Commit Graph

1303 Commits

Author SHA1 Message Date
mrambacher
618bf638aa Add Functions to OptionTypeInfo (#6422)
Summary:
Added functions for parsing, serializing, and comparing elements to OptionTypeInfo.  These functions allow all of the special cases that could not be handled directly in the map of OptionTypeInfo to be moved into the map.  Using these functions, every type can be handled via the map rather than special cased.

By adding these functions, the code for handling options can become more standardized (fewer special cases) and (eventually) handled completely by common classes.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6422

Test Plan: pass make check

Reviewed By: siying

Differential Revision: D21269005

Pulled By: zhichao-cao

fbshipit-source-id: 9ba71c721a38ebf9ee88259d60bd81b3282b9077
2020-04-28 18:04:26 -07:00
Peter Dillinger
bae6f58696 Basic MultiGet support for partitioned filters (#6757)
Summary:
In MultiGet, access each applicable filter partition only once
per batch, rather than for each applicable key. Also,

* Fix Bloom stats for MultiGet
* Fix/refactor MultiGetContext::Range::KeysLeft, including
* Add efficient BitsSetToOne implementation
* Assert that MultiGetContext::Range does not go beyond shift range

Performance test: Generate db:

    $ ./db_bench --benchmarks=fillrandom --num=15000000 --cache_index_and_filter_blocks -bloom_bits=10 -partition_index_and_filters=true
    ...

Before (middle performing run of three; note some missing Bloom stats):

    $ ./db_bench --use-existing-db --benchmarks=multireadrandom --num=15000000 --cache_index_and_filter_blocks --bloom_bits=10 --threads=16 --cache_size=20000000 -partition_index_and_filters -batch_size=32 -multiread_batched -statistics --duration=20 2>&1 | egrep 'micros/op|block.cache.filter.hit|bloom.filter.(full|use)|number.multiget'
    multireadrandom :      26.403 micros/op 597517 ops/sec; (548427 of 671968 found)
    rocksdb.block.cache.filter.hit COUNT : 83443275
    rocksdb.bloom.filter.useful COUNT : 0
    rocksdb.bloom.filter.full.positive COUNT : 0
    rocksdb.bloom.filter.full.true.positive COUNT : 7931450
    rocksdb.number.multiget.get COUNT : 385984
    rocksdb.number.multiget.keys.read COUNT : 12351488
    rocksdb.number.multiget.bytes.read COUNT : 793145000
    rocksdb.number.multiget.keys.found COUNT : 7931450

After (middle performing run of three):

    $ ./db_bench_new --use-existing-db --benchmarks=multireadrandom --num=15000000 --cache_index_and_filter_blocks --bloom_bits=10 --threads=16 --cache_size=20000000 -partition_index_and_filters -batch_size=32 -multiread_batched -statistics --duration=20 2>&1 | egrep 'micros/op|block.cache.filter.hit|bloom.filter.(full|use)|number.multiget'
    multireadrandom :      21.024 micros/op 752963 ops/sec; (705188 of 863968 found)
    rocksdb.block.cache.filter.hit COUNT : 49856682
    rocksdb.bloom.filter.useful COUNT : 45684579
    rocksdb.bloom.filter.full.positive COUNT : 10395458
    rocksdb.bloom.filter.full.true.positive COUNT : 9908456
    rocksdb.number.multiget.get COUNT : 481984
    rocksdb.number.multiget.keys.read COUNT : 15423488
    rocksdb.number.multiget.bytes.read COUNT : 990845600
    rocksdb.number.multiget.keys.found COUNT : 9908456

So that's about 25% higher throughput even for random keys
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6757

Test Plan: unit test included

Reviewed By: anand1976

Differential Revision: D21243256

Pulled By: pdillinger

fbshipit-source-id: 5644a1468d9e8c8575be02f4e04bc5d62dbbb57f
2020-04-28 14:49:34 -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
Peter Dillinger
249eff0f30 Stats for redundant insertions into block cache (#6681)
Summary:
Since read threads do not coordinate on loading data into block
cache, two threads between Lookup and Insert can end up loading and
inserting the same data. This is particularly concerning with
cache_index_and_filter_blocks since those are hot and more likely to
be race targets if ejected from (or not pre-populated in) the cache.

Particularly with moves toward disaggregated / network storage, the cost
of redundant retrieval might be high, and we should at least have some
hard statistics from which we can estimate impact.

Example with full filter thrashing "cliff":

    $ ./db_bench --benchmarks=fillrandom --num=15000000 --cache_index_and_filter_blocks -bloom_bits=10
    ...
    $ ./db_bench --db=/tmp/rocksdbtest-172704/dbbench --use_existing_db --benchmarks=readrandom,stats --num=200000 --cache_index_and_filter_blocks --cache_size=$((130 * 1024 * 1024)) --bloom_bits=10 --threads=16 -statistics 2>&1 | egrep '^rocksdb.block.cache.(.*add|.*redundant)' | grep -v compress | sort
    rocksdb.block.cache.add COUNT : 14181
    rocksdb.block.cache.add.failures COUNT : 0
    rocksdb.block.cache.add.redundant COUNT : 476
    rocksdb.block.cache.data.add COUNT : 12749
    rocksdb.block.cache.data.add.redundant COUNT : 18
    rocksdb.block.cache.filter.add COUNT : 1003
    rocksdb.block.cache.filter.add.redundant COUNT : 217
    rocksdb.block.cache.index.add COUNT : 429
    rocksdb.block.cache.index.add.redundant COUNT : 241
    $ ./db_bench --db=/tmp/rocksdbtest-172704/dbbench --use_existing_db --benchmarks=readrandom,stats --num=200000 --cache_index_and_filter_blocks --cache_size=$((120 * 1024 * 1024)) --bloom_bits=10 --threads=16 -statistics 2>&1 | egrep '^rocksdb.block.cache.(.*add|.*redundant)' | grep -v compress | sort
    rocksdb.block.cache.add COUNT : 1182223
    rocksdb.block.cache.add.failures COUNT : 0
    rocksdb.block.cache.add.redundant COUNT : 302728
    rocksdb.block.cache.data.add COUNT : 31425
    rocksdb.block.cache.data.add.redundant COUNT : 12
    rocksdb.block.cache.filter.add COUNT : 795455
    rocksdb.block.cache.filter.add.redundant COUNT : 130238
    rocksdb.block.cache.index.add COUNT : 355343
    rocksdb.block.cache.index.add.redundant COUNT : 172478
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6681

Test Plan: Some manual testing (above) and unit test covering key metrics is included

Reviewed By: ltamasi

Differential Revision: D21134113

Pulled By: pdillinger

fbshipit-source-id: c11497b5f00f4ffdfe919823904e52d0a1a91d87
2020-04-27 13:20:27 -07:00
Cheng Chang
40497a875a Reduce memory copies when fetching and uncompressing blocks from SST files (#6689)
Summary:
In https://github.com/facebook/rocksdb/pull/6455, we modified the interface of `RandomAccessFileReader::Read` to be able to get rid of memcpy in direct IO mode.
This PR applies the new interface to `BlockFetcher` when reading blocks from SST files in direct IO mode.

Without this PR, in direct IO mode, when fetching and uncompressing compressed blocks, `BlockFetcher` will first copy the raw compressed block into `BlockFetcher::compressed_buf_` or `BlockFetcher::stack_buf_` inside `RandomAccessFileReader::Read` depending on the block size. then during uncompressing, it will copy the uncompressed block into `BlockFetcher::heap_buf_`.

In this PR, we get rid of the first memcpy and directly uncompress the block from `direct_io_buf_` to `heap_buf_`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6689

Test Plan: A new unit test `block_fetcher_test` is added.

Reviewed By: anand1976

Differential Revision: D21006729

Pulled By: cheng-chang

fbshipit-source-id: 2370b92c24075692423b81277415feb2aed5d980
2020-04-24 15:32:56 -07:00
anand76
9e7b7e2c08 Silence false alarms in db_stress fault injection (#6741)
Summary:
False alarms are caused by codepaths that intentionally swallow IO
errors.

Tests:
make crash_test
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6741

Reviewed By: ltamasi

Differential Revision: D21181138

Pulled By: anand1976

fbshipit-source-id: 5ccfbc68eb192033488de6269e59c00f2c65ce00
2020-04-24 13:06:12 -07:00
Ibrahim Jarif
ae77880223 Fix some typos in code comments (#6733)
Summary:
This PR fixes some typos in code comments.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6733

Reviewed By: siying

Differential Revision: D21209037

Pulled By: zhichao-cao

fbshipit-source-id: d9274611fab1f5e992998c8c4117b8078c4cbc69
2020-04-23 12:28:49 -07:00
mrambacher
4cbc19d2a1 Add a ConfigOptions for use in comparing objects and converting to/from strings (#6389)
Summary:
The methods in convenience.h are used to compare/convert objects to/from strings.  There is a mishmash of parameters in use here with more needed in the future.  This PR replaces those parameters with a single structure.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6389

Reviewed By: siying

Differential Revision: D21163707

Pulled By: zhichao-cao

fbshipit-source-id: f807b4cc7e2b0af3871536b69546b2604dfa81bd
2020-04-21 17:38:17 -07:00
Andrew Kryczka
f9155a3404 Prevent uninitialized load in IndexBlockIter (#6736)
Summary:
When index block is empty or an error happens while reading it,
`Invalidate()` is called rather than `Initialize()`. So `Seek()` must
not refer to member variables that are only initialized in
`Initialize()` until it is sure `Initialize()` has been called.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6736

Reviewed By: siying

Differential Revision: D21139641

Pulled By: ajkr

fbshipit-source-id: 71c58cc1adbd795dc3729dd5023bf7df1515ff32
2020-04-20 16:32:43 -07:00
Peter Dillinger
31da5e34c1 C++20 compatibility (#6697)
Summary:
Based on https://github.com/facebook/rocksdb/issues/6648 (CLA Signed), but heavily modified / extended:

* Implicit capture of this via [=] deprecated in C++20, and [=,this] not standard before C++20 -> now using explicit capture lists
* Implicit copy operator deprecated in gcc 9 -> add explicit '= default' definition
* std::random_shuffle deprecated in C++17 and removed in C++20 -> migrated to a replacement in RocksDB random.h API
* Add the ability to build with different std version though -DCMAKE_CXX_STANDARD=11/14/17/20 on the cmake command line
* Minimal rebuild flag of MSVC is deprecated and is forbidden with /std:c++latest (C++20)
* Added MSVC 2019 C++11 & MSVC 2019 C++20 in AppVeyor
* Added GCC 9 C++11 & GCC9 C++20 in Travis
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6697

Test Plan: make check and CI

Reviewed By: cheng-chang

Differential Revision: D21020318

Pulled By: pdillinger

fbshipit-source-id: 12311be5dbd8675a0e2c817f7ec50fa11c18ab91
2020-04-20 13:24:25 -07:00
Peter Dillinger
45d2b4efca Fix tabs and lint-ignores (#6734)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/6734

Reviewed By: cheng-chang

Differential Revision: D21134556

Pulled By: pdillinger

fbshipit-source-id: 3636cc1d1333137b70031f8277458781c21631fb
2020-04-20 11:39:31 -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
Ziyue Yang
41563b61db Fix data racing of BlockBasedTableBuilder::ParallelCompressionRep::first_block (#6640)
Summary:
BlockBasedTableBuilder::ParallelCompressionRep::first_block can be read in
Flush() and written in BGWorkWriteRawBlock() concurrently. This commit fixes
the issue by reading first_block out before pushing the block to compression
and write.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6640

Test Plan: Run all tests concurrently with TSAN.

Reviewed By: cheng-chang

Differential Revision: D20851370

fbshipit-source-id: 6f039222e8319d31e15f1b45e05c106527253f72
2020-04-13 16:24:57 -07:00
Andrew Kryczka
9eca6d651d fix comparison count for format_version=3 indexes (#6650)
Summary:
In index blocks since `format_version=3`, user keys are written
rather than internal keys. When reading such blocks, the comparator is
obtained via `InternalKeyComparator::user_comparator()`. That function
must not return an unwrapped result as the wrapper class provides
accounting logic to populate `PerfContext::user_key_comparison_count`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6650

Test Plan:
ran db_bench and verified
`PerfContext::user_key_comparison_count` became larger.

Reviewed By: cheng-chang

Differential Revision: D20866325

Pulled By: ajkr

fbshipit-source-id: ad755d46bda31157dacc5b66e532279f19ad538c
2020-04-13 11:18:37 -07:00
anand76
79c838eb0f Fix a few bugs in db_stress fault injection (#6693)
Summary:
Fix the following issues -
1. Output parsing error in db_crashtest.py
2. Memory leak on exit
3. False alarm on filter block read error
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6693

Test Plan: asan_crash

Reviewed By: cheng-chang

Differential Revision: D20990399

Pulled By: anand1976

fbshipit-source-id: 178ee0dd7c69a4bc5db698379db0dedb29281699
2020-04-13 11:01:03 -07:00
anand76
5c19a441c4 Fault injection in db_stress (#6538)
Summary:
This PR implements a fault injection mechanism for injecting errors in reads in db_stress. The FaultInjectionTestFS is used for this purpose. A thread local structure is used to track the errors, so that each db_stress thread can independently enable/disable error injection and verify observed errors against expected errors. This is initially enabled only for Get and MultiGet, but can be extended to iterator as well once its proven stable.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6538

Test Plan:
crash_test
make check

Reviewed By: riversand963

Differential Revision: D20714347

Pulled By: anand1976

fbshipit-source-id: d7598321d4a2d72bda0ced57411a337a91d87dc7
2020-04-10 17:21:26 -07:00
anand76
d600e5b0eb Fix a Centos build failure reported in #6651 (#6656)
Summary:
Fixes issue https://github.com/facebook/rocksdb/issues/6651

Tests:
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6656

Reviewed By: cheng-chang

Differential Revision: D20879084

Pulled By: anand1976

fbshipit-source-id: c2cc508ca2716fcf80dcf9d2ba31c32d211f941e
2020-04-10 11:47:46 -07:00
Yi Wu
eb287c72d7 Fix wrong key being read on ingested file with global seqno and delta encoding (#6669)
Summary:
On reading an ingested SST file, `DataBlockIter` will replace seqno encoded in a key with global seqno. However, if the original seqno was part of the prefix used for the next key, the global seqno is by mistake used as part of the prefix to construct the next key, causing wrong result being returned. Although at this point it is only software error while data in the file is not corrupted, the issue can further cause compaction output out of order and corrupted result when the ingested SST participated in compaction. Fixing the issue by save the actual seqno and restore it before the key being used as prefix to construct next key.

The unit test is by Little-Wallace from https://github.com/facebook/rocksdb/issues/6666. Fixing https://github.com/facebook/rocksdb/issues/6666.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6669

Test Plan:
New unit test

Signed-off-by: Yi Wu <yiwu@pingcap.com>

Reviewed By: cheng-chang

Differential Revision: D20931808

Pulled By: ajkr

fbshipit-source-id: f01959c35d6a493954dca981663766c7a5a9e8ab
2020-04-08 21:22:15 -07:00
anand76
fcd7bee925 Properly account block_decompress_time (#6658)
Summary:
It was incorrectly counting time even for blocks that didn't need decompression.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6658

Test Plan: make check

Reviewed By: ajkr

Differential Revision: D20883522

Pulled By: anand1976

fbshipit-source-id: 33c9c4683f54cad150ab260a69e3ef8aa9aff76a
2020-04-07 12:53:59 -07:00
sdong
00f8016b36 Fix clang anaylze warning caused by #6262 (#6641)
Summary:
https://github.com/facebook/rocksdb/pull/6262 causes CLANG analyze to complain. Add assertion to suppress the warning.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6641

Test Plan: Run "clang analyze" and make sure it passes.

Reviewed By: anand1976

Differential Revision: D20841722

fbshipit-source-id: 5fa6e0c5cfe7a822214c9b898a408df59d4fd2cd
2020-04-03 15:47:51 -07:00
mrambacher
259b6ec8da Move the OptionTypeMap code closer to home (#6198)
Summary:
This is a predecessor to the Configurable PR.  This change moves the OptionTypeInfo maps closer to where they will be used.

When the Configurable changes are adopted, these values will become static and not associated with the OptionsHelper.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6198

Reviewed By: siying

Differential Revision: D20778108

Pulled By: zhichao-cao

fbshipit-source-id: a9f85fc73bc53503656e1958ecc1e764052fd1aa
2020-04-03 10:52:38 -07:00
Burton Li
df62cd5b35 Fix msvc debug test failures (#6579)
Summary:
1. stats_history_test: one slice of stats history is 12526 Bytes, which is greater than original assumption.
![image](https://user-images.githubusercontent.com/17753898/77381970-5a611a80-6d3c-11ea-9d64-59d2e3c04f79.png)
2. table_test: in VerifyBlockAccessTrace function, release trace reader before delete trace file.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6579

Reviewed By: siying

Differential Revision: D20767373

Pulled By: pdillinger

fbshipit-source-id: e8647d665cbe83a3f5429639c6219b50c0912124
2020-04-03 09:54:25 -07:00
sdong
d0f3894cf1 In block based table builder, make variables for estimating file size atomic (#6636)
Summary:
With https://github.com/facebook/rocksdb/issues/6262, TSAN complains about data race of some variables. Those variables are used to estimate file size and are accessed in writer and background threads. Since file size estimation doesn't have to be 100% accurate, we make some variables atomic and use relaxed memory order.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6636

Test Plan: Run all tests with TSAN.

Reviewed By: anand1976

Differential Revision: D20820635

fbshipit-source-id: 1ea45ff38be15e33674ffe06b7d42fc9fe161ea5
2020-04-02 16:16:24 -07:00
Ziyue Yang
8088482dd6 Fix a division by zero after #6262 (#6633)
Summary:
With https://github.com/facebook/rocksdb/issues/6262, UBSAN fails with "division by zero":

[ RUN      ] Timestamp/DBBasicTestWithTimestampCompressionSettings.PutAndGetWithCompaction/3
internal_repo_rocksdb/repo/table/block_based/block_based_table_builder.cc:1066:39: runtime error: division by zero
    #0 0x7ffb3117b071 in rocksdb::BlockBasedTableBuilder::WriteRawBlock(rocksdb::Slice const&, rocksdb::CompressionType, rocksdb::BlockHandle*, bool) internal_repo_rocksdb/repo/table/block_based/block_based_table_builder.cc:1066
    https://github.com/facebook/rocksdb/issues/1 0x7ffb311775e1 in rocksdb::BlockBasedTableBuilder::WriteBlock(rocksdb::Slice const&, rocksdb::BlockHandle*, bool) internal_repo_rocksdb/repo/table/block_based/block_based_table_builder.cc:848
    https://github.com/facebook/rocksdb/issues/2 0x7ffb311771a2 in rocksdb::BlockBasedTableBuilder::WriteBlock(rocksdb::BlockBuilder*, rocksdb::BlockHandle*, bool) internal_repo_rocksdb/repo/table/block_based/block_based_table_builder.cc:832

This is caused by not returning immediately after CompressAndVerifyBlock call
in WriteBlock when rep_->status == kBuffered.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6633

Test Plan: Run all existing test.

Reviewed By: anand1976

Differential Revision: D20808366

fbshipit-source-id: 09f24b7c0fbaf4c7a8fc48cac61fa6fcb9b85811
2020-04-02 11:57:05 -07:00
Ziyue Yang
03a781a90c Add pipelined & parallel compression optimization (#6262)
Summary:
This PR adds support for pipelined & parallel compression optimization for `BlockBasedTableBuilder`. This optimization makes block building, block compression and block appending a pipeline, and uses multiple threads to accelerate block compression. Users can set `CompressionOptions::parallel_threads` greater than 1 to enable compression parallelism.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6262

Reviewed By: ajkr

Differential Revision: D20651306

fbshipit-source-id: 62125590a9c15b6d9071def9dc72589c1696a4cb
2020-04-01 16:40:18 -07:00
Levi Tamasi
e6f86cfb36 Revert the recent cache deleter change (#6620)
Summary:
Revert "Use function objects as deleters in the block cache (https://github.com/facebook/rocksdb/issues/6545)"

    This reverts commit 6301dbe7a7.

    Revert "Call out the cache deleter related interface change in HISTORY.md (https://github.com/facebook/rocksdb/issues/6606)"

    This reverts commit 3a35542f86.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6620

Test Plan: `make check`

Reviewed By: zhichao-cao

Differential Revision: D20773311

Pulled By: ltamasi

fbshipit-source-id: 7637a761f718f323ef0e7da959462e8fb06e7a2b
2020-03-31 16:11:06 -07:00
sdong
80979f81c7 Make options.bottommost_compression, compression_opts and bottommost_compression_opts dynamically changeable. (#6615)
Summary:
These three options should be made dynamically changeable. Simply add them to MutableCFOptions and made the change.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6615

Test Plan: Add a unit test to make sure that SetOptions() can change the options.

Reviewed By: riversand963

Differential Revision: D20755951

fbshipit-source-id: 8165f4fd7a7a665cc7fb049698935022a5d2e7ff
2020-03-31 12:11:42 -07:00
Zhichao Cao
2ae91c6097 Fix potential memory leak in table_test (#6611)
Summary:
The checksum generator should be released if file_writer fails to reset the pointer.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6611

Test Plan: pass make asan_check

Reviewed By: riversand963

Differential Revision: D20742964

Pulled By: zhichao-cao

fbshipit-source-id: cde41be2edb3d1e56083c2b93e1510fb32556146
2020-03-30 14:11:27 -07:00
Zhichao Cao
e8d332d97e Use FileChecksumGenFactory for SST file checksum (#6600)
Summary:
In the current implementation, sst file checksum is calculated by a shared checksum function object, which may make some checksum function hard to be applied here such as SHA1. In this implementation, each sst file will have its own checksum generator obejct, created by FileChecksumGenFactory. User needs to implement its own FilechecksumGenerator and Factory to plugin the in checksum calculation method.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6600

Test Plan: tested with make asan_check

Reviewed By: riversand963

Differential Revision: D20717670

Pulled By: zhichao-cao

fbshipit-source-id: 2a74c1c280ac11a07a1980185b43b671acaa71c6
2020-03-29 15:58:46 -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
Levi Tamasi
6301dbe7a7 Use function objects as deleters in the block cache (#6545)
Summary:
As the first step of reintroducing eviction statistics for the block
cache, the patch switches from using simple function pointers as deleters
to function objects implementing an interface. This will enable using
deleters that have state, like a smart pointer to the statistics object
that is to be updated when an entry is removed from the cache. For now,
the patch adds a deleter template class `SimpleDeleter`, which simply
casts the `value` pointer to its original type and calls `delete` or
`delete[]` on it as appropriate. Note: to prevent object lifecycle
issues, deleters must outlive the cache entries referring to them;
`SimpleDeleter` ensures this by using the ("leaky") Meyers singleton
pattern.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6545

Test Plan: `make asan_check`

Reviewed By: siying

Differential Revision: D20475823

Pulled By: ltamasi

fbshipit-source-id: fe354c33dd96d9bafc094605462352305449a22a
2020-03-26 16:19:58 -07:00
Mike Kolupaev
963af52f15 Fix iterator reading filter block despite read_tier == kBlockCacheTier (#6562)
Summary:
We're seeing iterators with `ReadOptions::read_tier == kBlockCacheTier` sometimes doing file reads. Stack trace:

```
rocksdb::RandomAccessFileReader::Read(unsigned long, unsigned long, rocksdb::Slice*, char*, bool) const
rocksdb::BlockFetcher::ReadBlockContents()
rocksdb::Status rocksdb::BlockBasedTable::MaybeReadBlockAndLoadToCache<rocksdb::ParsedFullFilterBlock>(rocksdb::FilePrefetchBuffer*, rocksdb::ReadOptions const&, rocksdb::BlockHandle const&, rocksdb::UncompressionDict const&, rocksdb::CachableEntry<rocksdb::ParsedFullFilterBlock>*, rocksdb::BlockType, rocksdb::GetContext*, rocksdb::BlockCacheLookupContext*, rocksdb::BlockContents*) const
rocksdb::Status rocksdb::BlockBasedTable::RetrieveBlock<rocksdb::ParsedFullFilterBlock>(rocksdb::FilePrefetchBuffer*, rocksdb::ReadOptions const&, rocksdb::BlockHandle const&, rocksdb::UncompressionDict const&, rocksdb::CachableEntry<rocksdb::ParsedFullFilterBlock>*, rocksdb::BlockType, rocksdb::GetContext*, rocksdb::BlockCacheLookupContext*, bool, bool) const
rocksdb::FilterBlockReaderCommon<rocksdb::ParsedFullFilterBlock>::ReadFilterBlock(rocksdb::BlockBasedTable const*, rocksdb::FilePrefetchBuffer*, rocksdb::ReadOptions const&, bool, rocksdb::GetContext*, rocksdb::BlockCacheLookupContext*, rocksdb::CachableEntry<rocksdb::ParsedFullFilterBlock>*)
rocksdb::FilterBlockReaderCommon<rocksdb::ParsedFullFilterBlock>::GetOrReadFilterBlock(bool, rocksdb::GetContext*, rocksdb::BlockCacheLookupContext*, rocksdb::CachableEntry<rocksdb::ParsedFullFilterBlock>*) const
rocksdb::FullFilterBlockReader::MayMatch(rocksdb::Slice const&, bool, rocksdb::GetContext*, rocksdb::BlockCacheLookupContext*) const
rocksdb::FullFilterBlockReader::RangeMayExist(rocksdb::Slice const*, rocksdb::Slice const&, rocksdb::SliceTransform const*, rocksdb::Comparator const*, rocksdb::Slice const*, bool*, bool, rocksdb::BlockCacheLookupContext*)
rocksdb::BlockBasedTable::PrefixMayMatch(rocksdb::Slice const&, rocksdb::ReadOptions const&, rocksdb::SliceTransform const*, bool, rocksdb::BlockCacheLookupContext*) const
rocksdb::BlockBasedTableIterator<rocksdb::DataBlockIter, rocksdb::Slice>::SeekImpl(rocksdb::Slice const*)
rocksdb::ForwardIterator::SeekInternal(rocksdb::Slice const&, bool)
rocksdb::DBIter::Seek(rocksdb::Slice const&)
```

`BlockBasedTableIterator::CheckPrefixMayMatch` was missing a check for `kBlockCacheTier`. This PR adds it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6562

Test Plan: deployed it to a logdevice test cluster and looked at logdevice's IO tracing.

Reviewed By: siying

Differential Revision: D20529368

Pulled By: al13n321

fbshipit-source-id: 65bf33964b1951464415c900336635fb20919611
2020-03-26 15:21:26 -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
Cheng Chang
4fc216649d Support direct IO in RandomAccessFileReader::MultiRead (#6446)
Summary:
By supporting direct IO in RandomAccessFileReader::MultiRead, the benefits of parallel IO (IO uring) and direct IO can be combined.

In direct IO mode, read requests are aligned and merged together before being issued to RandomAccessFile::MultiRead, so blocks in the original requests might share the same underlying buffer, the shared buffers are returned in `aligned_bufs`, which is a new parameter of the `MultiRead` API.

For example, suppose alignment requirement for direct IO is 4KB, one request is (offset: 1KB, len: 1KB), another request is (offset: 3KB, len: 1KB), then since they all belong to page (offset: 0, len: 4KB), `MultiRead` only reads the page with direct IO into a buffer on heap, and returns 2 Slices referencing regions in that same buffer. See `random_access_file_reader_test.cc` for more examples.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6446

Test Plan: Added a new test `random_access_file_reader_test.cc`.

Reviewed By: anand1976

Differential Revision: D20097518

Pulled By: cheng-chang

fbshipit-source-id: ca48a8faf9c3af146465c102ef6b266a363e78d1
2020-03-20 16:33:26 -07:00
sdong
712bc4b6a2 Fix regression bug in partitioned index reseek caused by #6531 (#6551)
Summary:
https://github.com/facebook/rocksdb/pull/6531 removed some code in partitioned index seek logic. By mistake the logic of storing previous index offset is removed, while the logic of using it is preserved, so that the code might use wrong value to determine reseeking condition.
This will trigger a bug, if following a Seek() not going to the last block, SeekToLast() is called, and then Seek() is called which should position the cursor to the block before SeekToLast().
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6551

Test Plan: Add a unit test that reproduces the bug. In the same unit test, also some reseek cases are covered to avoid regression.

Reviewed By: pdillinger

Differential Revision: D20493990

fbshipit-source-id: 3919aa4861c0481ec96844e053048da1a934b91d
2020-03-17 12:33:10 -07:00
akankshamahajan
a8149aef1e Allow table/sst_file_reader_test.cc to use custom Env (#6536)
Summary:
Allowing table/sst_file_reader_test.cc to use custom Env specified by TEST_ENV_URI.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6536

Reviewed By: riversand963

Differential Revision: D20448525

Pulled By: akankshamahajan15

fbshipit-source-id: 74e4d34c8ac4c2743741e78bf599571a4a465459
2020-03-17 11:02:13 -07:00
Yanqin Jin
098dce2d1a Fix compiler warning treated as error (#6547)
Summary:
Define a private member variable only in debug mode. Without fix, build will fail
```
In file included from table/block_based/partitioned_index_iterator.cc:9:
./table/block_based/partitioned_index_iterator.h:125:32: error: private field 'icomp_' is not used [-Werror,-Wunused-private-field]
  const InternalKeyComparator& icomp_;
```

Test plan (dev server)
1. make check
2. Make sure fixed in Travis
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6547

Reviewed By: siying

Differential Revision: D20480027

Pulled By: pdillinger

fbshipit-source-id: 288bc94280e240c3136335b6c73eb1ccb0db459d
2020-03-17 09:59:28 -07:00
sdong
d66908091d De-template block based table iterator (#6531)
Summary:
Right now block based table iterator is used as both of iterating data for block based table, and for the index iterator for partitioend index. This was initially convenient for introducing a new iterator and block type for new index format, while reducing code change. However, these two usage doesn't go with each other very well. For example, Prev() is never called for partitioned index iterator, and some other complexity is maintained in block based iterators, which is not needed for index iterator but maintainers will always need to reason about it. Furthermore, the template usage is not following Google C++ Style which we are following, and makes a large chunk of code tangled together. This commit separate the two iterators. Right now, here is what it is done:
1. Copy the block based iterator code into partitioned index iterator, and de-template them.
2. Remove some code not needed for partitioned index. The upper bound check and tricks are removed. We never tested performance for those tricks when partitioned index is enabled in the first place. It's unlikelyl to generate performance regression, as creating new partitioned index block is much rarer than data blocks.
3. Separate out the prefetch logic to a helper class and both classes call them.

This commit will enable future follow-ups. One direction is that we might separate index iterator interface for data blocks and index blocks, as they are quite different.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6531

Test Plan: build using make and cmake. And build release

Differential Revision: D20473108

fbshipit-source-id: e48011783b339a4257c204cc07507b171b834b0f
2020-03-16 12:20:50 -07:00
sdong
674cf41732 Divide block_based_table_reader.cc (#6527)
Summary:
block_based_table_reader.cc is a giant file, which makes it hard for users to navigate the code. Divide the files to multiple files.
Some class templates cannot be moved to .cc file. They are moved to .h files. It is still better than including them all in block_based_table_reader.cc.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6527

Test Plan: "make all check" and "make release". Also build using cmake.

Differential Revision: D20428455

fbshipit-source-id: ca713c698469f07f35bc0c271358c0874ed4eb28
2020-03-12 21:41:50 -07:00
Yanqin Jin
d93812c9ae Iterator with timestamp (#6255)
Summary:
Preliminary support for iterator with user timestamp. Current implementation does not consider merge operator and reverse iterator. Auto compaction is also disabled in unit tests.

Create an iterator with timestamp.
```
...
read_opts.timestamp = &ts;
auto* iter = db->NewIterator(read_opts);
// target is key without timestamp.
for (iter->Seek(target); iter->Valid(); iter->Next()) {}
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {}
delete iter;
read_opts.timestamp = &ts1;
// lower_bound and upper_bound are without timestamp.
read_opts.iterate_lower_bound = &lower_bound;
read_opts.iterate_upper_bound = &upper_bound;
auto* iter1 = db->NewIterator(read_opts);
// Do Seek or SeekToFirst()
delete iter1;
```

Test plan (dev server)
```
$make check
```

Simple benchmarking (dev server)
1. The overhead introduced by this PR even when timestamp is disabled.
key size: 16 bytes
value size: 100 bytes
Entries: 1000000
Data reside in main memory, and try to stress iterator.
Repeated three times on master and this PR.
- Seek without next
```
./db_bench -db=/dev/shm/rocksdbtest-1000 -benchmarks=fillseq,seekrandom -enable_pipelined_write=false -disable_wal=true -format_version=3
```
master: 159047.0 ops/sec
this PR: 158922.3 ops/sec (2% drop in throughput)
- Seek and next 10 times
```
./db_bench -db=/dev/shm/rocksdbtest-1000 -benchmarks=fillseq,seekrandom -enable_pipelined_write=false -disable_wal=true -format_version=3 -seek_nexts=10
```
master: 109539.3 ops/sec
this PR: 107519.7 ops/sec (2% drop in throughput)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6255

Differential Revision: D19438227

Pulled By: riversand963

fbshipit-source-id: b66b4979486f8474619f4aa6bdd88598870b0746
2020-03-06 16:24:27 -08:00
Cheng Chang
0a0151fb99 Remove memcpy from RandomAccessFileReader::Read in direct IO mode (#6455)
Summary:
In direct IO mode, RandomAccessFileReader::Read allocates an internal aligned buffer, and then copies the result into the scratch buffer. If the result is only temporarily used inside a function, there is no need to do the memcpy and just let the result Slice refer to the internally allocated buffer.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6455

Test Plan: make check

Differential Revision: D20106753

Pulled By: cheng-chang

fbshipit-source-id: 44f505843837bba47a56e3fa2c4dd3bd76486b58
2020-03-06 14:05:12 -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
Michael R. Crusoe
051696bf98 fix some spelling typos (#6464)
Summary:
Found from Debian's "Lintian" program
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6464

Differential Revision: D20162862

Pulled By: zhichao-cao

fbshipit-source-id: 06941ee2437b038b2b8045becbe9d2c6fbff3e12
2020-02-28 14:14:03 -08:00
Cheng Chang
741decfe37 Return early on failure when constructing CuckooTableReader (#6453)
Summary:
If file is not mmaped, CuckooTableReader should not try to read table properties from the file.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6453

Test Plan: Added a new unit test

Differential Revision: D20103334

Pulled By: cheng-chang

fbshipit-source-id: 48539f14d93f6c1ebe12c3df5a14719e9d7b8726
2020-02-25 16:48:28 -08:00
Andrew Kryczka
69679e7375 Fix range deletion tombstone ingestion with global seqno (#6429)
Summary:
Original author: jeffrey-xiao

If we are writing a global seqno for an ingested file, the range
tombstone metablock gets accessed and put into the cache during
ingestion preparation. At the time, the global seqno of the ingested
file has not yet been determined, so the cached block will not have a
global seqno. When the file is ingested and we read its range tombstone
metablock, it will be returned from the cache with no global seqno. In
that case, we use the actual seqnos stored in the range tombstones,
which are all zero, so the tombstones cover nothing.

This commit removes global_seqno_ variable from Block. When iterating
over a block, the global seqno for the block is determined by the
iterator instead of storing this mutable attribute in Block.
Additionally, this commit adds a regression test to check that keys are
deleted when ingesting a file with a global seqno and range deletion
tombstones.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6429

Differential Revision: D19961563

Pulled By: ajkr

fbshipit-source-id: 5cf777397fa3e452401f0bf0364b0750492487b7
2020-02-25 15:31:48 -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
Cheng Chang
152f8a8ffe Remove unnecessary computation of index (#6406)
Summary:
`index` can be replaced by  `iter`, saving the computation of `index++`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6406

Test Plan: make check

Differential Revision: D19905056

Pulled By: cheng-chang

fbshipit-source-id: add4638959c0d2e4e77a11f3fa04ffabaf0de790
2020-02-14 08:26:23 -08:00
anand76
3e49249d30 Ensure all MultiGet IO errors are propagated to user (#6403)
Summary:
Unrevert the previous fix to propagate error status, and an additional fix to not treat a memtable lookup MergeInProgress status as an error.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6403

Test Plan:
Unit tests
Tried running stress tests but couldn't repro the stress failure

Differential Revision: D19846721

Pulled By: anand1976

fbshipit-source-id: 7db10cccbdc863d9b559497f0a46b608d2488ca4
2020-02-11 17:27:22 -08:00
anand76
35ed530d2c Revert "Check KeyContext status in MultiGet (#6387)" (#6401)
Summary:
This reverts commit d70011bccc. The commit is causing some stress test failure due to unexpected Status::MergeInProgress() return for some keys.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6401

Differential Revision: D19826623

Pulled By: anand1976

fbshipit-source-id: edd634cede9cb7bdd2cb8f46e662ea709b16d2f1
2020-02-10 22:23:36 -08:00
Zhichao Cao
4369f2c7bb Checksum for each SST file and stores in MANIFEST (#6216)
Summary:
In the current code base, RocksDB generate the checksum for each block and verify the checksum at usage. Current PR enable SST file checksum. After a SST file is generated by Flush or Compaction, RocksDB generate the SST file checksum and store the checksum value and checksum method name in the vs_info and MANIFEST as part for the FileMetadata.

Added the enable_sst_file_checksum to Options to enable or disable file checksum. Added sst_file_checksum to Options such that user can plugin their own SST file checksum calculate method via overriding the SstFileChecksum class. The checksum information inlcuding uint32_t checksum value and a checksum name (string).  A new tool is added to LDB such that user can dump out a list of file checksum information from MANIFEST. If user enables the file checksum but does not provide the sst_file_checksum instance, RocksDB will use the default crc32checksum implemented in table/sst_file_checksum_crc32c.h
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6216

Test Plan: Added the testing case in table_test and ldb_cmd_test to verify checksum is correct in different level. Pass make asan_check.

Differential Revision: D19171461

Pulled By: zhichao-cao

fbshipit-source-id: b2e53479eefc5bb0437189eaa1941670e5ba8b87
2020-02-10 15:52:52 -08:00
anand76
d70011bccc Check KeyContext status in MultiGet (#6387)
Summary:
Currently, any IO errors and checksum mismatches while reading data
blocks, are being ignored by the batched MultiGet. Its only looking at
the GetContext state. Fix that.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6387

Test Plan: Add unit tests

Differential Revision: D19799819

Pulled By: anand1976

fbshipit-source-id: 46133dccbb04e64067b9fe6cda73e282203db969
2020-02-07 16:48:16 -08:00
sdong
8f2bee6747 Add ReadOptions.auto_prefix_mode (#6314)
Summary:
Add a new option ReadOptions.auto_prefix_mode. When set to true, iterator should return the same result as total order seek, but may choose to do prefix seek internally, based on iterator upper bounds. Also fix two previous bugs when handling prefix extrator changes: (1) reverse iterator should not rely on upper bound to determine prefix. Fix it with skipping prefix check. (2) block-based filter is not handled properly.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6314

Test Plan: (1) add a unit test; (2) add the check to stress test and run see whether it can pass at least one run.

Differential Revision: D19458717

fbshipit-source-id: 51c1bcc5cdd826c2469af201979a39600e779bce
2020-01-28 14:44:05 -08:00
sdong
f10f135938 Fix regression bug of hash index with iterator total order seek (#6328)
Summary:
https://github.com/facebook/rocksdb/pull/6028 introduces a bug for hash index in SST files. If a table reader is created when total order seek is used, prefix_extractor might be passed into table reader as null. While later when prefix seek is used, the same table reader used, hash index is checked but prefix extractor is null and the program would crash.
Fix the issue by fixing http://github.com/facebook/rocksdb/pull/6028 in the way that prefix_extractor is preserved but ReadOptions.total_order_seek is checked

Also, a null pointer check is added so that a bug like this won't cause segfault in the future.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6328

Test Plan: Add a unit test that would fail without the fix. Stress test that reproduces the crash would pass.

Differential Revision: D19586751

fbshipit-source-id: 8de77690167ddf5a77a01e167cf89430b1bfba42
2020-01-27 15:44:54 -08:00
Peter Dillinger
986df37135 Clean up PartitionedFilterBlockBuilder (#6299)
Summary:
Remove the redundant PartitionedFilterBlockBuilder::num_added_ and ::NumAdded since the parent class, FullFilterBlockBuilder, already provides them.
Also rename filters_in_partition_ and filters_per_partition_ to keys_added_to_partition_ and keys_per_partition_ to improve readability.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6299

Test Plan: make check

Differential Revision: D19413278

Pulled By: pdillinger

fbshipit-source-id: 04926ee7874477d659cb2b6ae03f2d995fb747e5
2020-01-27 13:15:14 -08:00
Peter Dillinger
8aa99fc71e Warn on excessive keys for legacy Bloom filter with 32-bit hash (#6317)
Summary:
With many millions of keys, the old Bloom filter implementation
for the block-based table (format_version <= 4) would have excessive FP
rate due to the limitations of feeding the Bloom filter with a 32-bit hash.
This change computes an estimated inflated FP rate due to this effect
and warns in the log whenever an SST filter is constructed (almost
certainly a "full" not "partitioned" filter) that exceeds 1.5x FP rate
due to this effect. The detailed condition is only checked if 3 million
keys or more have been added to a filter, as this should be a lower
bound for common bits/key settings (< 20).

Recommended remedies include smaller SST file size, using
format_version >= 5 (for new Bloom filter), or using partitioned
filters.

This does not change behavior other than generating warnings for some
constructed filters using the old implementation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6317

Test Plan:
Example with warning, 15M keys @ 15 bits / key: (working_mem_size_mb is just to stop after building one filter if it's large)

    $ ./filter_bench -quick -impl=0 -working_mem_size_mb=1 -bits_per_key=15 -average_keys_per_filter=15000000 2>&1 | grep 'FP rate'
    [WARN] [/block_based/filter_policy.cc:292] Using legacy SST/BBT Bloom filter with excessive key count (15.0M @ 15bpk), causing estimated 1.8x higher filter FP rate. Consider using new Bloom with format_version>=5, smaller SST file size, or partitioned filters.
    Predicted FP rate %: 0.766702
    Average FP rate %: 0.66846

Example without warning (150K keys):

    $ ./filter_bench -quick -impl=0 -working_mem_size_mb=1 -bits_per_key=15 -average_keys_per_filter=150000 2>&1 | grep 'FP rate'
    Predicted FP rate %: 0.422857
    Average FP rate %: 0.379301
    $

With more samples at 15 bits/key:
  150K keys -> no warning; actual: 0.379% FP rate (baseline)
  1M keys -> no warning; actual: 0.396% FP rate, 1.045x
  9M keys -> no warning; actual: 0.563% FP rate, 1.485x
  10M keys -> warning (1.5x); actual: 0.564% FP rate, 1.488x
  15M keys -> warning (1.8x); actual: 0.668% FP rate, 1.76x
  25M keys -> warning (2.4x); actual: 0.880% FP rate, 2.32x

At 10 bits/key:
  150K keys -> no warning; actual: 1.17% FP rate (baseline)
  1M keys -> no warning; actual: 1.16% FP rate
  10M keys -> no warning; actual: 1.32% FP rate, 1.13x
  25M keys -> no warning; actual: 1.63% FP rate, 1.39x
  35M keys -> warning (1.6x); actual: 1.81% FP rate, 1.55x

At 5 bits/key:
  150K keys -> no warning; actual: 9.32% FP rate (baseline)
  25M keys -> no warning; actual: 9.62% FP rate, 1.03x
  200M keys -> no warning; actual: 12.2% FP rate, 1.31x
  250M keys -> warning (1.5x); actual: 12.8% FP rate, 1.37x
  300M keys -> warning (1.6x); actual: 13.4% FP rate, 1.43x

The reason for the modest inaccuracy at low bits/key is that the assumption of independence between a collision between 32-hash values feeding the filter and an FP in the filter is not quite true for implementations using "simple" logic to compute indices from the stock hash result. There's math on this in my dissertation, but I don't think it's worth the effort just for these extreme cases (> 100 million keys and low-ish bits/key).

Differential Revision: D19471715

Pulled By: pdillinger

fbshipit-source-id: f80c96893a09bf1152630ff0b964e5cdd7e35c68
2020-01-20 21:31:47 -08:00
Peter Dillinger
4b86fe1123 Log warning for high bits/key in legacy Bloom filter (#6312)
Summary:
Help users that would benefit most from new Bloom filter
implementation by logging a warning that recommends the using
format_version >= 5.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6312

Test Plan:
$ (for BPK in 10 13 14 19 20 50; do ./filter_bench -quick -impl=0 -bits_per_key=$BPK -m_queries=1 2>&1; done) | grep 'its/key'
    Bits/key actual: 10.0647
    Bits/key actual: 13.0593
    [WARN] [/block_based/filter_policy.cc:546] Using legacy Bloom filter with high (14) bits/key. Significant filter space and/or accuracy improvement is available with format_verion>=5.
    Bits/key actual: 14.0581
    [WARN] [/block_based/filter_policy.cc:546] Using legacy Bloom filter with high (19) bits/key. Significant filter space and/or accuracy improvement is available with format_verion>=5.
    Bits/key actual: 19.0542
    [WARN] [/block_based/filter_policy.cc:546] Using legacy Bloom filter with high (20) bits/key. Dramatic filter space and/or accuracy improvement is available with format_verion>=5.
    Bits/key actual: 20.0584
    [WARN] [/block_based/filter_policy.cc:546] Using legacy Bloom filter with high (50) bits/key. Dramatic filter space and/or accuracy improvement is available with format_verion>=5.
    Bits/key actual: 50.0577

Differential Revision: D19457191

Pulled By: pdillinger

fbshipit-source-id: 073d94cde5c70e03a160f953e1100c15ea83eda4
2020-01-17 19:37:35 -08:00
sdong
d87cffaea4 Fix another bug caused by recent hash index fix (#6305)
Summary:
Recent bug fix related to hash index introduced a new bug: hash index can return NotFound but it is not handled by BlockBasedTable::Get(). The end result is that Get() stops being executed too early. Fix it by ignoring NotFound code in Get().
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6305

Test Plan: A problematic DB used to return NotFound incorrectly, and now able to return correct result. Will try to construct a unit test too.0

Differential Revision: D19438925

fbshipit-source-id: e751afa8c13728d56511cfeb1bc811ecb99f3217
2020-01-17 01:41:04 -08:00
sdong
f8b5ef85ec Fix a bug caused by recent fix of Prefix Hash (#6302)
Summary:
Recent fix to Prefix Hash https://github.com/facebook/rocksdb/pull/6292 caused a bug that the newly created NotFound status in hash index is never reset. This causes reseek or implict reseek to return wrong results sometimes.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6302

Test Plan:
Add a unit test that would fail. Not fix.
crash test with hash test would fail in several seconds. With the fix, it will run about several minutes before failing with another failure.

Differential Revision: D19424572

fbshipit-source-id: c5276f36a95fd0e2837e30190476d2fe21ed8566
2020-01-16 10:47:20 -08:00
sdong
d2b4d42d4b Fix kHashSearch bug with SeekForPrev (#6297)
Summary:
When prefix is enabled the expected behavior when the prefix of the target does not exist is for Seek is to seek to any key larger than target and SeekToPrev to any key less than the target.
Currently. the prefix index (kHashSearch) returns OK status but sets Invalid() to indicate two cases: a prefix of the searched key does not exist, ii) the key is beyond the range of the keys in SST file. The SeekForPrev implementation in BlockBasedTable thus does not have enough information to know when it should set the index key to first (to return a key smaller than target). The patch fixes that by returning NotFound status for cases that the prefix does not exist. SeekForPrev in BlockBasedTable accordingly SeekToFirst instead of SeekToLast on the index iterator.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6297

Test Plan: SeekForPrev of non-exsiting prefix is added to block_test.cc, and a test case is added in db_test2, which fails without the fix.

Differential Revision: D19404695

fbshipit-source-id: cafbbf95f8f60ff9ede9ccc99d25bfa1cf6fcdc3
2020-01-15 14:28:39 -08:00
Maysam Yabandeh
d4b7fbf0d5 kHashSearch incompatible with index_block_restart_interval>1 (#6294)
Summary:
kHashSearch index type is incompatible with index_block_restart_interval larger than 1. The patch asserts that and also resets index_block_restart_interval value if it is incompatible with kHashSearch.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6294

Differential Revision: D19394229

Pulled By: maysamyabandeh

fbshipit-source-id: 8a12712ab25e81094a7f71ecd43f773dd4fb6acd
2020-01-14 11:21:27 -08:00
Yanqin Jin
946c43a026 Improve error msg for SstFileWriter Merge (#6261)
Summary:
Reword the error message when keys are not added in strict ascending order.
Specifically, original error message is not clear when application tries to
call SstFileWriter::Merge() with duplicate keys.

Test plan (dev server)
```
make check
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6261

Differential Revision: D19290398

Pulled By: riversand963

fbshipit-source-id: 4dc30a701414e6894db2eb024e3734470c22b371
2020-01-06 10:57:22 -08:00
sdong
f295b099f6 BlockBasedTable::ApproximateSize() should use total order seek (#6222)
Summary:
Right now BlockBasedTable::ApproximateSize() uses default setting about whether to use total order seek. There is no reason for that. There is no reason to do any filtering for approximate size boundary key, and it may introduce bugs. Disable it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6222

Test Plan: Run existing tests

Differential Revision: D19184787

fbshipit-source-id: 64180660bd2800914fff75104172b61c06f0b1c9
2019-12-19 14:56:38 -08:00
Maysam Yabandeh
77d5ba7887 Revert "Add kHashSearch to stress tests (#6210)" (#6220)
Summary:
This reverts commit 54f9092b0c.
It making our daily stress tests fail. Revert it until the issues are fixed.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6220

Differential Revision: D19179881

Pulled By: maysamyabandeh

fbshipit-source-id: 99de0eaf776567fa81110b9ad2608234a16083ce
2019-12-19 10:46:55 -08:00
Maysam Yabandeh
54f9092b0c Add kHashSearch to stress tests (#6210)
Summary:
Beside extending index_type to kHashSearch, it clarifies in the code base that this feature is incompatible with index_block_restart_interval > 1.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6210

Test Plan:
```
make -j32 crash_test

Differential Revision: D19166567

Pulled By: maysamyabandeh

fbshipit-source-id: 3aaf75a70a8b462d372d43aac69dbd10df303ec7
2019-12-18 18:09:30 -08:00
sdong
02193ce406 Prevent file prefetch when mmap is enabled. (#6206)
Summary:
Right now, sometimes file prefetching is still on when mmap is enabled. This causes bug of reading wrong data. In this commit, we remove all those possible paths.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6206

Test Plan: make crash_test with compaction_readahead_size, which used to fail. RUn all existing tests.

Differential Revision: D19149429

fbshipit-source-id: 9e18ea8c566e416aac9647bdd05afe596634791b
2019-12-18 11:01:29 -08:00
Zhichao Cao
c399704c7a Fix: remove the potential dead store variable in block_based_table_reader.cc (#6204)
Summary:
buf_offset does not need to get the value from req.len for othe final block. It can cause test fail for clan_analyze. Remove it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6204

Test Plan: pass make asan_check

Differential Revision: D19145335

Pulled By: zhichao-cao

fbshipit-source-id: 8f6e74565746381b5c5ef598b97d746517b36e5b
2019-12-18 01:23:07 -08:00
Zhichao Cao
cddd637997 Merge adjacent file block reads in RocksDB MultiGet() and Add uncompressed block to cache (#6089)
Summary:
In the current MultiGet, if the KV-pairs do not belong to the data blocks in the block cache, multiple blocks are read from a SST. It will trigger one block read for each block request and read them in parallel. In some cases, if some data blocks are adjacent in the SST, the reads for these blocks can be combined to a single large read, which can reduce the system calls and reduce the read latency if possible.

Considering to fill the block cache, if multiple data blocks are in the same memory buffer, we need to copy them to the heap separately. Therefore, only in the case that 1) data block compression is enabled, and 2) compressed block cache is null, we can do combined read. Otherwise, extra memory copy is needed, which may cause extra overhead. In the current case, data blocks will be uncompressed to a new memory space.

Also, in the case that 1) data block compression is enabled, and 2) compressed block cache is null, it is possible the data block is actually not compressed. In the current logic, these data blocks will not be added to the uncompressed_cache. So if memory buffer is shared and the data block is not compressed, the data block are copied to the head and fill the cache.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6089

Test Plan: Added test case to ParallelIO.MultiGet. Pass make asan_check

Differential Revision: D18734668

Pulled By: zhichao-cao

fbshipit-source-id: 67c5615ed373e51e42635fd74b36f8f3a66d5da4
2019-12-16 16:26:03 -08:00
Peter Dillinger
a92bd0a183 Optimize memory and CPU for building new Bloom filter (#6175)
Summary:
The filter bits builder collects all the hashes to add in memory before adding them (because the number of keys is not known until we've walked over all the keys). Existing code uses a std::vector for this, which can mean up to 2x than necessary space allocated (and not freed) and up to ~2x write amplification in memory. Using std::deque uses close to minimal space (for large filters, the only time it matters), no write amplification, frees memory while building, and no need for large contiguous memory area. The only cost is more calls to allocator, which does not appear to matter, at least in benchmark test.

For now, this change only applies to the new (format_version=5) Bloom filter implementation, to ease before-and-after comparison downstream.

Temporary memory use during build is about the only way the new Bloom filter could regress vs. the old (because of upgrade to 64-bit hash) and that should only matter for full filters. This change should largely mitigate that potential regression.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6175

Test Plan:
Using filter_bench with -new_builder option and 6M keys per filter is like large full filter (improvement). 10k keys and no -new_builder is like partitioned filters (about the same). (Corresponding configurations run simultaneously on devserver.)

std::vector impl (before)

    $ /usr/bin/time -v ./filter_bench -impl=2 -quick -new_builder -working_mem_size_mb=1000 -
    average_keys_per_filter=6000000
    Build avg ns/key: 52.2027
    Maximum resident set size (kbytes): 1105016
    $ /usr/bin/time -v ./filter_bench -impl=2 -quick -working_mem_size_mb=1000 -
    average_keys_per_filter=10000
    Build avg ns/key: 30.5694
    Maximum resident set size (kbytes): 1208152

std::deque impl (after)

    $ /usr/bin/time -v ./filter_bench -impl=2 -quick -new_builder -working_mem_size_mb=1000 -
    average_keys_per_filter=6000000
    Build avg ns/key: 39.0697
    Maximum resident set size (kbytes): 1087196
    $ /usr/bin/time -v ./filter_bench -impl=2 -quick -working_mem_size_mb=1000 -
    average_keys_per_filter=10000
    Build avg ns/key: 30.9348
    Maximum resident set size (kbytes): 1207980

Differential Revision: D19053431

Pulled By: pdillinger

fbshipit-source-id: 2888e748723a19d9ea40403934f13cbb8483430c
2019-12-15 21:31:08 -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
sdong
a68dff5c35 Apply formatter to some recent commits (#6138)
Summary:
Formatter somehow complains some recent lines changed. Apply them to make the formatter happy.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6138

Test Plan: See CI passes.

Differential Revision: D18895950

fbshipit-source-id: 7d1696cf3e3a682bc10a30cdca748a23c6565255
2019-12-09 15:49:49 -08:00
Peter Dillinger
e43d2c4424 Fix & test rocksdb_filterpolicy_create_bloom_full (#6132)
Summary:
Add overrides needed in FilterPolicy wrapper to fix
rocksdb_filterpolicy_create_bloom_full (see issue https://github.com/facebook/rocksdb/issues/6129). Re-enabled
assertion in BloomFilterPolicy::CreateFilter that was being violated.
Expanded c_test to identify Bloom filter implementations by FP counts.
(Without the fix, updated test will trigger assertion and fail otherwise
without the assertion.)

Fixes https://github.com/facebook/rocksdb/issues/6129
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6132

Test Plan: updated c_test, also run under valgrind.

Differential Revision: D18864911

Pulled By: pdillinger

fbshipit-source-id: 08e81d7b5368b08e501cd402ef5583f2650c19fa
2019-12-09 12:21:14 -08:00
Ziyue Yang
7e2f831924 Fix wrong ExtractUserKey usage in BlockBasedTableBuilder::EnterUnbuff… (#6100)
Summary:
BlockBasedTableBuilder uses ExtractUserKey in EnterUnbuffered. This would
cause index filter building error, since user-provided timestamp is supported
by ExtractUserKeyAndStripTimestamp, and it's used in Add. This commit changes
ExtractUserKey to ExtractUserKeyAndStripTimestamp.

A test case is also added by modifying DBBasicTestWithTimestampWithParam_
PutAndGet test in db_basic_test to cover ExtractUserKeyAndStripTimestamp usage
in both kBuffered and kUnbuffered state of BlockBasedTableBuilder.

Before the ExtractUserKeyAndStripTimstamp fix:

```
$ ./db_basic_test --gtest_filter="*PutAndGet*"
Note: Google Test filter = *PutAndGet*
[==========] Running 2 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 2 tests from Timestamp/DBBasicTestWithTimestampWithParam
[ RUN      ] Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/0
db/db_basic_test.cc:2109: Failure
db_->Get(ropts, cfh, "key" + std::to_string(j), &value)
NotFound:
db/db_basic_test.cc:2109: Failure
db_->Get(ropts, cfh, "key" + std::to_string(j), &value)
NotFound:
db/db_basic_test.cc:2109: Failure
db_->Get(ropts, cfh, "key" + std::to_string(j), &value)
NotFound:
db/db_basic_test.cc:2109: Failure
db_->Get(ropts, cfh, "key" + std::to_string(j), &value)
NotFound:
db/db_basic_test.cc:2109: Failure
db_->Get(ropts, cfh, "key" + std::to_string(j), &value)
NotFound:
[  FAILED  ] Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/0, where GetParam() = false (1177 ms)
[ RUN      ] Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/1
[       OK ] Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/1 (1056 ms)
[----------] 2 tests from Timestamp/DBBasicTestWithTimestampWithParam (2233 ms total)

[----------] Global test environment tear-down
[==========] 2 tests from 1 test case ran. (2233 ms total)
[  PASSED  ] 1 test.
[  FAILED  ] 1 test, listed below:
[  FAILED  ] Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/0, where GetParam() = false

 1 FAILED TEST
```

After the ExtractUserKeyAndStripTimstamp fix:

```
$ ./db_basic_test --gtest_filter="*PutAndGet*"
Note: Google Test filter = *PutAndGet*
[==========] Running 2 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 2 tests from Timestamp/DBBasicTestWithTimestampWithParam
[ RUN      ] Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/0
[       OK ] Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/0 (1417 ms)
[ RUN      ] Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/1
[       OK ] Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/1 (1041 ms)
[----------] 2 tests from Timestamp/DBBasicTestWithTimestampWithParam (2458 ms total)

[----------] Global test environment tear-down
[==========] 2 tests from 1 test case ran. (2458 ms total)
[  PASSED  ] 2 tests.
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6100

Differential Revision: D18769654

Pulled By: riversand963

fbshipit-source-id: 76c2cf2c9a5e0d85db95d98e812e6af0c2a15c6b
2019-12-09 10:57:02 -08:00
Peter Dillinger
6db57bc37f Disable new Bloom filter assertion (#6128)
Summary:
A longstanding bug in our C interface can trigger this
assertion; see issue https://github.com/facebook/rocksdb/issues/6129. Disabling the assertion for now
(for 6.6.0) and will re-enable on fix of that bug.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6128

Differential Revision: D18854899

Pulled By: pdillinger

fbshipit-source-id: 9eb5294b9f11b208dc1a8cc148aaa31e47ff892b
2019-12-06 10:28:02 -08:00
Peter Dillinger
ca3b6c28c9 Expose and elaborate FilterBuildingContext (#6088)
Summary:
This change enables custom implementations of FilterPolicy to
wrap a variety of NewBloomFilterPolicy and select among them based on
contextual information such as table level and compaction style.

* Moves FilterBuildingContext to public API and elaborates it with more
useful data. (It would be nice to put more general options-like data,
but at the time this object is constructed, we are using internal APIs
ImmutableCFOptions and MutableCFOptions and don't have easy access to
ColumnFamilyOptions that I can tell.)

* Renames BloomFilterPolicy::GetFilterBitsBuilderInternal to
GetBuilderWithContext, because it's now public.

* Plumbs through the table's "level_at_creation" for filter building
context.

* Simplified some tests by adding GetBuilder() to
MockBlockBasedTableTester.

* Adds test as DBBloomFilterTest.ContextCustomFilterPolicy, including
sample wrapper class LevelAndStyleCustomFilterPolicy.

* Fixes a cross-test bug in DBBloomFilterTest.OptimizeFiltersForHits
where it does not reset perf context.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6088

Test Plan: make check, valgrind on db_bloom_filter_test

Differential Revision: D18697817

Pulled By: pdillinger

fbshipit-source-id: 5f987a2d7b07cc7a33670bc08ca6b4ca698c1cf4
2019-11-26 18:24:10 -08:00
Peter Dillinger
57f3032285 Allow fractional bits/key in BloomFilterPolicy (#6092)
Summary:
There's no technological impediment to allowing the Bloom
filter bits/key to be non-integer (fractional/decimal) values, and it
provides finer control over the memory vs. accuracy trade-off. This is
especially handy in using the format_version=5 Bloom filter in place
of the old one, because bits_per_key=9.55 provides the same accuracy as
the old bits_per_key=10.

This change not only requires refining the logic for choosing the best
num_probes for a given bits/key setting, it revealed a flaw in that logic.
As bits/key gets higher, the best num_probes for a cache-local Bloom
filter is closer to bpk / 2 than to bpk * 0.69, the best choice for a
standard Bloom filter. For example, at 16 bits per key, the best
num_probes is 9 (FP rate = 0.0843%) not 11 (FP rate = 0.0884%).
This change fixes and refines that logic (for the format_version=5
Bloom filter only, just in case) based on empirical tests to find
accuracy inflection points between each num_probes.

Although bits_per_key is now specified as a double, the new Bloom
filter converts/rounds this to "millibits / key" for predictable/precise
internal computations. Just in case of unforeseen compatibility
issues, we round to the nearest whole number bits / key for the
legacy Bloom filter, so as not to unlock new behaviors for it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6092

Test Plan: unit tests included

Differential Revision: D18711313

Pulled By: pdillinger

fbshipit-source-id: 1aa73295f152a995328cb846ef9157ae8a05522a
2019-11-26 15:59:34 -08:00
Peter Dillinger
ac498cdb86 Remove a few unnecessary includes
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/6046

Test Plan: make check, manual inspection

Differential Revision: D18573044

Pulled By: pdillinger

fbshipit-source-id: 7a5999fc08d798ce3157b56d4b36d24027409fc3
2019-11-19 08:20:42 -08:00
Peter Dillinger
f059c7d9b9 New Bloom filter implementation for full and partitioned filters (#6007)
Summary:
Adds an improved, replacement Bloom filter implementation (FastLocalBloom) for full and partitioned filters in the block-based table. This replacement is faster and more accurate, especially for high bits per key or millions of keys in a single filter.

Speed

The improved speed, at least on recent x86_64, comes from
* Using fastrange instead of modulo (%)
* Using our new hash function (XXH3 preview, added in a previous commit), which is much faster for large keys and only *slightly* slower on keys around 12 bytes if hashing the same size many thousands of times in a row.
* Optimizing the Bloom filter queries with AVX2 SIMD operations. (Added AVX2 to the USE_SSE=1 build.) Careful design was required to support (a) SIMD-optimized queries, (b) compatible non-SIMD code that's simple and efficient, (c) flexible choice of number of probes, and (d) essentially maximized accuracy for a cache-local Bloom filter. Probes are made eight at a time, so any number of probes up to 8 is the same speed, then up to 16, etc.
* Prefetching cache lines when building the filter. Although this optimization could be applied to the old structure as well, it seems to balance out the small added cost of accumulating 64 bit hashes for adding to the filter rather than 32 bit hashes.

Here's nominal speed data from filter_bench (200MB in filters, about 10k keys each, 10 bits filter data / key, 6 probes, avg key size 24 bytes, includes hashing time) on Skylake DE (relatively low clock speed):

$ ./filter_bench -quick -impl=2 -net_includes_hashing # New Bloom filter
Build avg ns/key: 47.7135
Mixed inside/outside queries...
  Single filter net ns/op: 26.2825
  Random filter net ns/op: 150.459
    Average FP rate %: 0.954651
$ ./filter_bench -quick -impl=0 -net_includes_hashing # Old Bloom filter
Build avg ns/key: 47.2245
Mixed inside/outside queries...
  Single filter net ns/op: 63.2978
  Random filter net ns/op: 188.038
    Average FP rate %: 1.13823

Similar build time but dramatically faster query times on hot data (63 ns to 26 ns), and somewhat faster on stale data (188 ns to 150 ns). Performance differences on batched and skewed query loads are between these extremes as expected.

The only other interesting thing about speed is "inside" (query key was added to filter) vs. "outside" (query key was not added to filter) query times. The non-SIMD implementations are substantially slower when most queries are "outside" vs. "inside". This goes against what one might expect or would have observed years ago, as "outside" queries only need about two probes on average, due to short-circuiting, while "inside" always have num_probes (say 6). The problem is probably the nastily unpredictable branch. The SIMD implementation has few branches (very predictable) and has pretty consistent running time regardless of query outcome.

Accuracy

The generally improved accuracy (re: Issue https://github.com/facebook/rocksdb/issues/5857) comes from a better design for probing indices
within a cache line (re: Issue https://github.com/facebook/rocksdb/issues/4120) and improved accuracy for millions of keys in a single filter from using a 64-bit hash function (XXH3p). Design details in code comments.

Accuracy data (generalizes, except old impl gets worse with millions of keys):
Memory bits per key: FP rate percent old impl -> FP rate percent new impl
6: 5.70953 -> 5.69888
8: 2.45766 -> 2.29709
10: 1.13977 -> 0.959254
12: 0.662498 -> 0.411593
16: 0.353023 -> 0.0873754
24: 0.261552 -> 0.0060971
50: 0.225453 -> ~0.00003 (less than 1 in a million queries are FP)

Fixes https://github.com/facebook/rocksdb/issues/5857
Fixes https://github.com/facebook/rocksdb/issues/4120

Unlike the old implementation, this implementation has a fixed cache line size (64 bytes). At 10 bits per key, the accuracy of this new implementation is very close to the old implementation with 128-byte cache line size. If there's sufficient demand, this implementation could be generalized.

Compatibility

Although old releases would see the new structure as corrupt filter data and read the table as if there's no filter, we've decided only to enable the new Bloom filter with new format_version=5. This provides a smooth path for automatic adoption over time, with an option for early opt-in.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6007

Test Plan: filter_bench has been used thoroughly to validate speed, accuracy, and correctness. Unit tests have been carefully updated to exercise new and old implementations, as well as the logic to select an implementation based on context (format_version).

Differential Revision: D18294749

Pulled By: pdillinger

fbshipit-source-id: d44c9db3696e4d0a17caaec47075b7755c262c5f
2019-11-13 16:44:01 -08:00
Peter Dillinger
42b5494ec8 Fix BloomFilterPolicy changes for unsigned char (ARM) (#6024)
Summary:
Bug in PR https://github.com/facebook/rocksdb/issues/5941 when char is unsigned that should only affect
assertion on unused/invalid filter metadata.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6024

Test Plan: on ARM: ./bloom_test && ./db_bloom_filter_test && ./block_based_filter_block_test && ./full_filter_block_test && ./partitioned_filter_block_test

Differential Revision: D18461206

Pulled By: pdillinger

fbshipit-source-id: 68a7c813a0b5791c05265edc03cdf52c78880e9a
2019-11-12 15:29:15 -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
anand76
03ce7fb292 Fix a buffer overrun problem in BlockBasedTable::MultiGet (#6014)
Summary:
The calculation in BlockBasedTable::MultiGet for the required buffer length for reading in compressed blocks is incorrect. It needs to take the 5-byte block trailer into account.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6014

Test Plan: Add a unit test DBBasicTest.MultiGetBufferOverrun that fails in asan_check before the fix, and passes after.

Differential Revision: D18412753

Pulled By: anand1976

fbshipit-source-id: 754dfb66be1d5f161a7efdf87be872198c7e3b72
2019-11-11 16:59:15 -08:00
anand76
9836a1fa33 Fix MultiGet crash when no_block_cache is set (#5991)
Summary:
This PR fixes https://github.com/facebook/rocksdb/issues/5975. In ```BlockBasedTable::RetrieveMultipleBlocks()```, we were calling ```MaybeReadBlocksAndLoadToCache()```, which is a no-op if neither uncompressed nor compressed block cache are configured.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5991

Test Plan:
1. Add unit tests that fail with the old code and pass with the new
2. make check and asan_check

Cc spetrunia

Differential Revision: D18272744

Pulled By: anand1976

fbshipit-source-id: e62fa6090d1a6adf84fcd51dfd6859b03c6aebfe
2019-11-07 12:02:21 -08:00
Yanqin Jin
67e735dbf9 Rename BlockBasedTable::ReadMetaBlock (#6009)
Summary:
According to
https://github.com/facebook/rocksdb/wiki/Rocksdb-BlockBasedTable-Format,
the block read by BlockBasedTable::ReadMetaBlock is actually the meta index
block. Therefore, it is better to rename the function to ReadMetaIndexBlock.

This PR also applies some format change to existing code.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6009

Test Plan: make check

Differential Revision: D18333238

Pulled By: riversand963

fbshipit-source-id: 2c4340a29b3edba53d19c132cbfd04caf6242aed
2019-11-05 17:19:11 -08:00
Peter Dillinger
18f57f5ef8 Add new persistent 64-bit hash (#5984)
Summary:
For upcoming new SST filter implementations, we will use a new
64-bit hash function (XXH3 preview, slightly modified). This change
updates hash.{h,cc} for that change, adds unit tests, and out-of-lines
the implementations to keep hash.h as clean/small as possible.

In developing the unit tests, I discovered that the XXH3 preview always
returns zero for the empty string. Zero is problematic for some
algorithms (including an upcoming SST filter implementation) if it
occurs more often than at the "natural" rate, so it should not be
returned from trivial values using trivial seeds. I modified our fork
of XXH3 to return a modest hash of the seed for the empty string.

With hash function details out-of-lines in hash.h, it makes sense to
enable XXH_INLINE_ALL, so that direct calls to XXH64/XXH32/XXH3p
are inlined. To fix array-bounds warnings on some inline calls, I
injected some casts to uintptr_t in xxhash.cc. (Issue reported to Yann.)
Revised: Reverted using XXH_INLINE_ALL for now.  Some Facebook
checks are unhappy about #include on xxhash.cc file. I would
fix that by rename to xxhash_cc.h, but to best preserve history I want
to do that in a separate commit (PR) from the uintptr casts.

Also updated filter_bench for this change, improving the performance
predictability of dry run hashing and adding support for 64-bit hash
(for upcoming new SST filter implementations, minor dead code in the
tool for now).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5984

Differential Revision: D18246567

Pulled By: pdillinger

fbshipit-source-id: 6162fbf6381d63c8cc611dd7ec70e1ddc883fbb8
2019-10-31 16:36:35 -07:00
Peter Dillinger
685e895652 Prepare filter tests for more implementations (#5967)
Summary:
This change sets up for alternate implementations underlying
BloomFilterPolicy:

* Refactor BloomFilterPolicy and expose in internal .h file so that it's easy to iterate over / select implementations for testing, regardless of what the best public interface will look like. Most notably updated db_bloom_filter_test to use this.
* Hide FullFilterBitsBuilder from unit tests (alternate derived classes planned); expose the part important for testing (CalculateSpace), as abstract class BuiltinFilterBitsBuilder. (Also cleaned up internally exposed interface to CalculateSpace.)
* Rename BloomTest -> BlockBasedBloomTest for clarity (despite ongoing confusion between block-based table and block-based filter)
* Assert that block-based filter construction interface is only used on BloomFilterPolicy appropriately constructed. (A couple of tests updated to add ", true".)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5967

Test Plan: make check

Differential Revision: D18138704

Pulled By: pdillinger

fbshipit-source-id: 55ef9273423b0696309e251f50b8c1b5e9ec7597
2019-10-31 14:12:33 -07:00
Peter Dillinger
013babc685 Clean up some filter tests and comments (#5960)
Summary:
Some filtering tests were unfriendly to new implementations of
FilterBitsBuilder because of dynamic_cast to FullFilterBitsBuilder. Most
of those have now been cleaned up, worked around, or at least changed
from crash on dynamic_cast failure to individual test failure.

Also put some clarifying comments on filter-related APIs.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5960

Test Plan: make check

Differential Revision: D18121223

Pulled By: pdillinger

fbshipit-source-id: e83827d9d5d96315d96f8e25a99cd70f497d802c
2019-10-24 18:48:16 -07:00
Peter Dillinger
ca7ccbe2ea Misc hashing updates / upgrades (#5909)
Summary:
- Updated our included xxhash implementation to version 0.7.2 (== the latest dev version as of 2019-10-09).
- Using XXH_NAMESPACE (like other fb projects) to avoid potential name collisions.
- Added fastrange64, and unit tests for it and fastrange32. These are faster alternatives to hash % range.
- Use preview version of XXH3 instead of MurmurHash64A for NPHash64
-- Had to update cache_test to increase probability of passing for any given hash function.
- Use fastrange64 instead of % with uses of NPHash64
-- Had to fix WritePreparedTransactionTest.CommitOfDelayedPrepared to avoid deadlock apparently caused by new hash collision.
- Set default seed for NPHash64 because specifying a seed rarely makes sense for it.
- Removed unnecessary include xxhash.h in a popular .h file
- Rename preview version of XXH3 to XXH3p for clarity and to ease backward compatibility in case final version of XXH3 is integrated.

Relying on existing unit tests for NPHash64-related changes. Each new implementation of fastrange64 passed unit tests when manipulating my local build to select it. I haven't done any integration performance tests, but I consider the improved performance of the pieces being swapped in to be well established.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5909

Differential Revision: D18125196

Pulled By: pdillinger

fbshipit-source-id: f6bf83d49d20cbb2549926adf454fd035f0ecc0d
2019-10-24 17:16:46 -07:00
Peter Dillinger
ec11eff3bc FilterPolicy consolidation, part 2/2 (#5966)
Summary:
The parts that are used to implement FilterPolicy /
NewBloomFilterPolicy and not used other than for the block-based table
should be consolidated under table/block_based/filter_policy*.

This change is step 2 of 2:
mv util/bloom.cc table/block_based/filter_policy.cc
This gets its own PR so that git has the best chance of following the
rename for blame purposes. Note that low-level shared implementation
details of Bloom filters remain in util/bloom_impl.h, and
util/bloom_test.cc remains where it is for now.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5966

Test Plan: make check

Differential Revision: D18124930

Pulled By: pdillinger

fbshipit-source-id: 823bc09025b3395f092ef46a46aa5ba92a914d84
2019-10-24 15:44:51 -07:00
Peter Dillinger
dd19014a7a FilterPolicy consolidation, part 1/2 (#5963)
Summary:
The parts that are used to implement FilterPolicy /
NewBloomFilterPolicy and not used other than for the block-based table
should be consolidated under table/block_based/filter_policy*. I don't
foresee sharing these APIs with e.g. the Plain Table because they don't
expose hashes for reuse in indexing.

This change is step 1 of 2:
(a) mv table/full_filter_bits_builder.h to
table/block_based/filter_policy_internal.h which I expect to expand
soon to internally reveal more implementation details for testing.
(b) consolidate eventual contents of table/block_based/filter_policy.cc
in util/bloom.cc, which has the most elaborate revision history
(see step 2 ...)

Step 2 soon to follow:
mv util/bloom.cc table/block_based/filter_policy.cc
This gets its own PR so that git has the best chance of following the
rename for blame purposes. Note that low-level shared implementation
details of Bloom filters are in util/bloom_impl.h.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5963

Test Plan: make check

Differential Revision: D18121199

Pulled By: pdillinger

fbshipit-source-id: 8f21732c3d8909777e3240e4ac3123d73140326a
2019-10-24 13:20:35 -07:00
Peter Dillinger
27a124571f Fix memory leak on error opening PlainTable (#5951)
Summary:
Several error paths in opening of a plain table would leak memory. PR https://github.com/facebook/rocksdb/issues/5940 opened the leak to one more error path, which happens to have been (mistakenly) exercised by CuckooTableDBTest.AdaptiveTable. That test has been fixed, and the exercising of
plain table error cases (more than before) has been added as BadOptions1 and BadOptions2
to PlainTableDBTest. This effectively moved the memory leak to plain_table_db_test.

Also here is a cheap fix for the memory leak, without (yet?) changing the signature of
ReadTableProperties. This fixes ASAN on unit tests.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5951

Test Plan: make COMPILE_WITH_ASAN=1 check

Differential Revision: D18051940

Pulled By: pdillinger

fbshipit-source-id: e2952930c09a2b46c4f1ff09818c5090426929de
2019-10-21 16:53:06 -07:00
sdong
30e2dc02f0 Fix VerifyChecksum readahead with mmap mode (#5945)
Summary:
A recent change introduced readahead inside VerifyChecksum(). However it is not compatible with mmap mode and generated wrong checksum verification failure. Fix it by not enabling readahead in mmap
 mode.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5945

Test Plan: Add a unit test that used to fail.

Differential Revision: D18021443

fbshipit-source-id: 6f2eb600f81b26edb02222563a4006869d576bff
2019-10-21 11:38:30 -07:00
Levi Tamasi
29ccf2075c Store the filter bits reader alongside the filter block contents (#5936)
Summary:
Amongst other things, PR https://github.com/facebook/rocksdb/issues/5504 refactored the filter block readers so that
only the filter block contents are stored in the block cache (as opposed to the
earlier design where the cache stored the filter block reader itself, leading to
potentially dangling pointers and concurrency bugs). However, this change
introduced a performance hit since with the new code, the metadata fields are
re-parsed upon every access. This patch reunites the block contents with the
filter bits reader to eliminate this overhead; since this is still a self-contained
pure data object, it is safe to store it in the cache. (Note: this is similar to how
the zstd digest is handled.)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5936

Test Plan:
make asan_check

filter_bench results for the old code:

```
$ ./filter_bench -quick
WARNING: Assertions are enabled; benchmarks unnecessarily slow
Building...
Build avg ns/key: 26.7153
Number of filters: 16669
Total memory (MB): 200.009
Bits/key actual: 10.0647
----------------------------
Inside queries...
  Dry run (46b) ns/op: 33.4258
  Single filter ns/op: 42.5974
  Random filter ns/op: 217.861
----------------------------
Outside queries...
  Dry run (25d) ns/op: 32.4217
  Single filter ns/op: 50.9855
  Random filter ns/op: 219.167
    Average FP rate %: 1.13993
----------------------------
Done. (For more info, run with -legend or -help.)

$ ./filter_bench -quick -use_full_block_reader
WARNING: Assertions are enabled; benchmarks unnecessarily slow
Building...
Build avg ns/key: 26.5172
Number of filters: 16669
Total memory (MB): 200.009
Bits/key actual: 10.0647
----------------------------
Inside queries...
  Dry run (46b) ns/op: 32.3556
  Single filter ns/op: 83.2239
  Random filter ns/op: 370.676
----------------------------
Outside queries...
  Dry run (25d) ns/op: 32.2265
  Single filter ns/op: 93.5651
  Random filter ns/op: 408.393
    Average FP rate %: 1.13993
----------------------------
Done. (For more info, run with -legend or -help.)
```

With the new code:

```
$ ./filter_bench -quick
WARNING: Assertions are enabled; benchmarks unnecessarily slow
Building...
Build avg ns/key: 25.4285
Number of filters: 16669
Total memory (MB): 200.009
Bits/key actual: 10.0647
----------------------------
Inside queries...
  Dry run (46b) ns/op: 31.0594
  Single filter ns/op: 43.8974
  Random filter ns/op: 226.075
----------------------------
Outside queries...
  Dry run (25d) ns/op: 31.0295
  Single filter ns/op: 50.3824
  Random filter ns/op: 226.805
    Average FP rate %: 1.13993
----------------------------
Done. (For more info, run with -legend or -help.)

$ ./filter_bench -quick -use_full_block_reader
WARNING: Assertions are enabled; benchmarks unnecessarily slow
Building...
Build avg ns/key: 26.5308
Number of filters: 16669
Total memory (MB): 200.009
Bits/key actual: 10.0647
----------------------------
Inside queries...
  Dry run (46b) ns/op: 33.2968
  Single filter ns/op: 58.6163
  Random filter ns/op: 291.434
----------------------------
Outside queries...
  Dry run (25d) ns/op: 32.1839
  Single filter ns/op: 66.9039
  Random filter ns/op: 292.828
    Average FP rate %: 1.13993
----------------------------
Done. (For more info, run with -legend or -help.)
```

Differential Revision: D17991712

Pulled By: ltamasi

fbshipit-source-id: 7ea205550217bfaaa1d5158ebd658e5832e60f29
2019-10-18 19:32:59 -07:00
Peter Dillinger
fe464bca5c Fix PlainTableReader not to crash sst_dump (#5940)
Summary:
Plain table SSTs could crash sst_dump because of a bug in
PlainTableReader that can leave table_properties_ as null. Even if it
was intended not to keep the table properties in some cases, they were
leaked on the offending code path.

Steps to reproduce:

    $ db_bench --benchmarks=fillrandom --num=2000000 --use_plain_table --prefix-size=12
    $ sst_dump --file=0000xx.sst --show_properties
    from [] to []
    Process /dev/shm/dbbench/000014.sst
    Sst file format: plain table
    Raw user collected properties
    ------------------------------
    Segmentation fault (core dumped)

Also added missing unit testing of plain table full_scan_mode, and
an assertion in NewIterator to check for regression.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5940

Test Plan: new unit test, manual, make check

Differential Revision: D18018145

Pulled By: pdillinger

fbshipit-source-id: 4310c755e824c4cd6f3f86a3abc20dfa417c5e07
2019-10-18 14:44:42 -07:00
Maysam Yabandeh
4e729f9095 Fix SeekForPrev bug with Partitioned Filters and Prefix (#5907)
Summary:
Partition Filters make use of a top-level index to find the partition that might have the bloom hash of the key. The index is with internal key format (before format version 3). Each partition contains the i) blooms of the keys in that range ii) bloom of prefixes of keys in that range, iii) the bloom of the prefix of the last key in the previous partition.
When ::SeekForPrev(key), we first perform a prefix bloom test on the SST file. The partition however is identified using the full internal key, rather than the prefix key. The reason is to be compatible with the internal key format of the top-level index. This creates a corner case. Example:
- SST k, Partition N: P1K1, P1K2
- SST k, top-level index: P1K2
- SST k+1, Partition 1: P2K1, P3K1
- SST k+1 top-level index: P3K1
When SeekForPrev(P1K3), it should point us to P1K2. However SST k top-level index would reject P1K3 since it is out of range.
One possible fix would be to search with the prefix P1 (instead of full internal key P1K3) however the details of properly comparing prefix with full internal key might get complicated. The fix we apply in this PR is to look into the last partition anyway even if the key is out of range.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5907

Differential Revision: D17889918

Pulled By: maysamyabandeh

fbshipit-source-id: 169fd7b3c71dbc08808eae5a8340611ebe5bdc1e
2019-10-11 20:30:00 -07:00
Andrew Kryczka
b00761eea6 Fix block cache ID uniqueness for Windows builds (#5844)
Summary:
Since we do not evict a file's blocks from block cache before that file
is deleted, we require a file's cache ID prefix is both unique and
non-reusable. However, the Windows functionality we were relying on only
guaranteed uniqueness. That meant a newly created file could be assigned
the same cache ID prefix as a deleted file. If the newly created file
had block offsets matching the deleted file, full cache keys could be
exactly the same, resulting in obsolete data blocks returned from cache
when trying to read from the new file.

We noticed this when running on FAT32 where compaction was writing out
of order keys due to reading obsolete blocks from its input files. The
functionality is documented as behaving the same on NTFS, although I
wasn't able to repro it there.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5844

Test Plan:
we had a reliable repro of out-of-order keys on FAT32 that
was fixed by this change

Differential Revision: D17752442

fbshipit-source-id: 95d983f9196cf415f269e19293b97341edbf7e00
2019-10-11 18:19:31 -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
Peter Dillinger
46ca51d430 filter_bench - a prelim tool for SST filter benchmarking (#5825)
Summary:
Example: using the tool before and after PR https://github.com/facebook/rocksdb/issues/5784 shows that
the refactoring, presumed performance-neutral, actually sped up SST
filters by about 3% to 8% (repeatable result):

Before:
-  Dry run ns/op: 22.4725
-  Single filter ns/op: 51.1078
-  Random filter ns/op: 120.133

After:
+  Dry run ns/op: 22.2301
+  Single filter run ns/op: 47.4313
+  Random filter ns/op: 115.9

Only tests filters for the block-based table (full filters and
partitioned filters - same implementation; not block-based filters),
which seems to be the recommended format/implementation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5825

Differential Revision: D17804987

Pulled By: pdillinger

fbshipit-source-id: 0f18a9c254c57f7866030d03e7fa4ba503bac3c5
2019-10-07 20:10:53 -07:00
anand76
19a97dd139 Fix data block upper bound checking for iterator reseek case (#5883)
Summary:
When an iterator reseek happens with the user specifying a new iterate_upper_bound in ReadOptions, and the new seek position is at the end of the same data block, the Seek() ends up using a stale value of data_block_within_upper_bound_ and may return incorrect results.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5883

Test Plan: Added a new test case DBIteratorTest.IterReseekNewUpperBound. Verified that it failed due to the assertion failure without the fix, and passes with the fix.

Differential Revision: D17752740

Pulled By: anand1976

fbshipit-source-id: f9b635ff5d6aeb0e1bef102cf8b2f900efd378e3
2019-10-03 20:53:29 -07:00
sdong
d783af1857 Fix a timer bug in MergingIterator::Seek() caused by #5871 (#5874)
Summary:
Conflict resolving in 846e05005d ("Revert "Merging iterator to avoid child iterator reseek for some cases") caused some timer misplaced. Fix it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5874

Test Plan: See it build.

Differential Revision: D17705073

fbshipit-source-id: 9bd3a8dc4901ac33c2c6fc5b1091ffbc56a8529f
2019-10-01 19:26:18 -07:00
Yanqin Jin
9f31df8679 Fix compilation error (#5872)
Summary:
Without this fix, compiler complains.
```
$ROCKSDB_NO_FBCODE=1 USE_CLANG=1 make ldb
table/block_based/full_filter_block.cc: In constructor ‘rocksdb::FullFilterBlockBuilder::FullFilterBlockBuilder(const rocksdb::SliceTransform*, bool, rocksdb::FilterBitsBuilder*)’:
table/block_based/full_filter_block.cc:20:43: error: declaration of ‘prefix_extractor’ shadows a member of 'this' [-Werror=shadow]
FilterBitsBuilder* filter_bits_builder)
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5872

Test Plan:
```
$ROCKSDB_NO_FBCODE=1 make all
```

Differential Revision: D17690058

Pulled By: riversand963

fbshipit-source-id: 19e3d9bd86e1123847095240e73d30da5d66240e
2019-10-01 14:07:13 -07:00
sdong
846e05005d Revert "Merging iterator to avoid child iterator reseek for some cases (#5286)" (#5871)
Summary:
This reverts commit 9fad3e21eb.

Iterator verification in stress tests sometimes fail for assertion
table/block_based/block_based_table_reader.cc:2973: void rocksdb::BlockBasedTableIterator<TBlockIter, TValue>::FindBlockForward() [with TBlockIter = rocksdb::DataBlockIter; TValue = rocksdb::Slice]: Assertion `!next_block_is_out_of_bound || user_comparator_.Compare(*read_options_.iterate_upper_bound, index_iter_->user_key()) <= 0' failed.

It is likely to be linked to https://github.com/facebook/rocksdb/pull/5286 together with https://github.com/facebook/rocksdb/pull/5468 as the former PR makes some child iterator's seek being avoided, so that upper bound condition fails to be updated there. Strictly speaking, the former PR was merged before the latter one, but the latter one feels a more important improvement so I choose to revert the former one for now.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5871

Differential Revision: D17689196

fbshipit-source-id: 4ded5be68f67bee2782d31a29cb72ea68f59dd8c
2019-10-01 11:22:41 -07:00
Maysam Yabandeh
6652c94f59 Fix a bug in format_version 3 + partition filters + prefix search (#5835)
Summary:
Partitioned filters make use of a top-level index to find the partition in which the filter resides. The top-level index has a key per partition. The key is guaranteed to be larger or equal than any key in that partition. When used with format_version 3, which excludes the sequence number form index keys, the separator key in the index could be equal to the prefix of the keys in the next partition. In this way, when searching for the key, the top-level index will lead us to the previous partition, which has no key with that prefix. The prefix bloom test thus returns false, although the prefix exists in the bloom of the next partition.
The patch fixes that by a hack: It always adds the prefix of the first key of the next partition to the bloom of the current partition. In this way, in the corner cases that the index will lead us to the previous partition, we still can find the bloom filter there.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5835

Differential Revision: D17513585

Pulled By: maysamyabandeh

fbshipit-source-id: e2d1ff26c759e6e03875c4d57f4228316ecf50e9
2019-09-24 14:00:11 -07:00
Levi Tamasi
c9932d18cc Add class comment for Block
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5832

Differential Revision: D17550773

Pulled By: ltamasi

fbshipit-source-id: 66972bb008516e55b6fbba58ddd10234346d5d11
2019-09-24 11:02:11 -07:00
sdong
e8263dbdaa Apply formatter to recent 200+ commits. (#5830)
Summary:
Further apply formatter to more recent commits.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5830

Test Plan: Run all existing tests.

Differential Revision: D17488031

fbshipit-source-id: 137458fd94d56dd271b8b40c522b03036943a2ab
2019-09-20 12:04:26 -07:00
Maysam Yabandeh
6ec6a4a9a4 Remove snap_refresh_nanos option (#5826)
Summary:
The snap_refresh_nanos option didn't bring much benefit. Remove the feature to simplify the code.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5826

Differential Revision: D17467147

Pulled By: maysamyabandeh

fbshipit-source-id: 4f950b046990d0d1292d7fc04c2ccafaf751c7f0
2019-09-18 20:26:04 -07:00
sdong
43a340bebe Merging iterator to disble reseek optimization in prefix seek (#5815)
Summary:
We are seeing a bug of wrong results with merging iterator's reseek avoidence feature and prefix extractor. Disable this optimization for now.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5815

Test Plan: Validated the same MyRocks case was fixed; run all existing tests.

Differential Revision: D17430776

fbshipit-source-id: aef664277ba0ab8a2e68331ff0db6ae682535371
2019-09-17 17:10:29 -07:00
Peter Dillinger
68626249c3 Refactor/consolidate legacy Bloom implementation details (#5784)
Summary:
Refactoring to consolidate implementation details of legacy
Bloom filters. This helps to organize and document some related,
obscure code.

Also added make/cpp var TEST_CACHE_LINE_SIZE so that it's easy to
compile and run unit tests for non-native cache line size. (Fixed a
related test failure in db_properties_test.)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5784

Test Plan:
make check, including Recently added Bloom schema unit tests
(in ./plain_table_db_test && ./bloom_test), and including with
TEST_CACHE_LINE_SIZE=128U and TEST_CACHE_LINE_SIZE=256U. Tested the
schema tests with temporary fault injection into new implementations.

Some performance testing with modified unit tests suggest a small to moderate
improvement in speed.

Differential Revision: D17381384

Pulled By: pdillinger

fbshipit-source-id: ee42586da996798910fc45ac0b6289147f16d8df
2019-09-16 16:17:09 -07:00
Maysam Yabandeh
638d239507 Charge block cache for cache internal usage (#5797)
Summary:
For our default block cache, each additional entry has extra memory overhead. It include LRUHandle (72 bytes currently) and the cache key (two varint64, file id and offset). The usage is not negligible. For example for block_size=4k, the overhead accounts for an extra 2% memory usage for the cache. The patch charging the cache for the extra usage, reducing untracked memory usage outside block cache. The feature is enabled by default and can be disabled by passing kDontChargeCacheMetadata to the cache constructor.
This PR builds up on https://github.com/facebook/rocksdb/issues/4258
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5797

Test Plan:
- Existing tests are updated to either disable the feature when the test has too much dependency on the old way of accounting the usage or increasing the cache capacity to account for the additional charge of metadata.
- The Usage tests in cache_test.cc are augmented to test the cache usage under kFullChargeCacheMetadata.

Differential Revision: D17396833

Pulled By: maysamyabandeh

fbshipit-source-id: 7684ccb9f8a40ca595e4f5efcdb03623afea0c6f
2019-09-16 15:26:21 -07:00
Peter Dillinger
d3a6726f02 Revert changes from PR#5784 accidentally in PR#5780 (#5810)
Summary:
This will allow us to fix history by having the code changes for PR#5784 properly attributed to it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5810

Differential Revision: D17400231

Pulled By: pdillinger

fbshipit-source-id: 2da8b1cdf2533cfedb35b5526eadefb38c291f09
2019-09-16 11:38:53 -07:00
sdong
b931f84e56 Divide file_reader_writer.h and .cc (#5803)
Summary:
file_reader_writer.h and .cc contain several files and helper function, and it's hard to navigate. Separate it to multiple files and put them under file/
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5803

Test Plan: Build whole project using make and cmake.

Differential Revision: D17374550

fbshipit-source-id: 10efca907721e7a78ed25bbf74dc5410dea05987
2019-09-16 10:33:51 -07:00
sdong
bf5dbc17e3 merging_iterator.cc: Small refactoring (#5793)
Summary:
1. Put the similar logic of adding valid iterator to heap and check invalid iterator's status code to the same helper functions.
2. Because of 1, in the changing direction case, move around the places where we check status a little bit so that we can call the helper function there too. The logic would only divert in the case where the iterator is valid but status is not OK, which is not expected to happen. Add an assertion for that.
3. Put the logic of changing direction from forward to backward to a separate function so the unlikely code path is not in Prev().
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5793

Test Plan: run all existing tests.

Differential Revision: D17374397

fbshipit-source-id: d595ffcf156095c4bd0f5532bacba854482a2332
2019-09-13 16:01:13 -07:00
Peter Dillinger
aa2486b23c Refactor some confusing logic in PlainTableReader
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5780

Test Plan: existing plain table unit test

Differential Revision: D17368629

Pulled By: pdillinger

fbshipit-source-id: f25409cdc2f39ebe8d5cbb599cf820270e6b5d26
2019-09-13 10:26:36 -07:00
Shylock Hg
9eb3e1f77d Use delete to disable automatic generated methods. (#5009)
Summary:
Use delete to disable automatic generated methods instead of private, and put the constructor together for more clear.This modification cause the unused field warning, so add unused attribute to disable this warning.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5009

Differential Revision: D17288733

fbshipit-source-id: 8a767ce096f185f1db01bd28fc88fef1cdd921f3
2019-09-11 18:09:00 -07:00
Wilfried Goesgens
fbab9913e2 upgrade gtest 1.7.0 => 1.8.1 for json result writing
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5332

Differential Revision: D17242232

fbshipit-source-id: c0d4646556a1335e51ac7382b986ca7f6ced7b64
2019-09-09 11:24:11 -07:00
Peter Dillinger
b55b2f45d0 Faster new DynamicBloom implementation (for memtable) (#5762)
Summary:
Since DynamicBloom is now only used in-memory, we're free to
change it without schema compatibility issues. The new implementation
is drawn from (with manifest permission)
303542a767/bloom_simulation_tests/foo.cc (L613)

This has several speed advantages over the prior implementation:
* Uses fastrange instead of %
* Minimum logic to determine first (and all) probed memory addresses
* (Major) Two probes per 64-bit memory fetch/write.
* Very fast and effective (murmur-like) hash expansion/re-mixing. (At
least on recent CPUs, integer multiplication is very cheap.)

While a Bloom filter with 512-bit cache locality has about a 1.15x FP
rate penalty (e.g. 0.84% to 0.97%), further restricting to two probes
per 64 bits incurs an additional 1.12x FP rate penalty (e.g. 0.97% to
1.09%). Nevertheless, the unit tests show no "mediocre" FP rate samples,
unlike the old implementation with more erratic FP rates.

Especially for the memtable, we expect speed to outweigh somewhat higher
FP rates. For example, a negative table query would have to be 1000x
slower than a BF query to justify doubling BF query time to shave 10% off
FP rate (working assumption around 1% FP rate). While that seems likely
for SSTs, my data suggests a speed factor of roughly 50x for the memtable
(vs. BF; ~1.5% lower write throughput when enabling memtable Bloom
filter, after this change).  Thus, it's probably not worth even 5% more
time in the Bloom filter to shave off 1/10th of the Bloom FP rate, or 0.1%
in absolute terms, and it's probably at least 20% slower to recoup that
much FP rate from this new implementation. Because of this, we do not see
a need for a 'locality' option that affects the MemTable Bloom filter
and have decoupled the MemTable Bloom filter from Options::bloom_locality.

Note that just 3% more memory to the Bloom filter (10.3 bits per key vs.
just 10) is able to make up for the ~12% FP rate drop in the new
implementation:

[] # Nearly "ideal" FP-wise but reasonably fast cache-local implementation
[~/wormhashing/bloom_simulation_tests] ./foo_gcc_IMPL_CACHE_WORM64_FROM32_any.out 10000000 6 10 $RANDOM 100000000
./foo_gcc_IMPL_CACHE_WORM64_FROM32_any.out time: 3.29372 sampled_fp_rate: 0.00985956 ...

[] # Close match to this new implementation
[~/wormhashing/bloom_simulation_tests] ./foo_gcc_IMPL_CACHE_MUL64_BLOCK_FROM32_any.out 10000000 6 10.3 $RANDOM 100000000
./foo_gcc_IMPL_CACHE_MUL64_BLOCK_FROM32_any.out time: 2.10072 sampled_fp_rate: 0.00985655 ...

[] # Old locality=1 implementation
[~/wormhashing/bloom_simulation_tests] ./foo_gcc_IMPL_CACHE_ROCKSDB_DYNAMIC_any.out 10000000 6 10 $RANDOM 100000000
./foo_gcc_IMPL_CACHE_ROCKSDB_DYNAMIC_any.out time: 3.95472 sampled_fp_rate: 0.00988943 ...

Also note the dramatic speed improvement vs. alternatives.

--

Performance unit test: DynamicBloomTest.concurrent_with_perf is updated
to report more precise timing data. (Measure running time of each
thread, not just longest running thread, etc.) Results averaged over
various sizes enabled with --enable_perf and 20 runs each; old dynamic
bloom refers to locality=1, the faster of the old:

old dynamic bloom, avg add latency = 65.6468
new dynamic bloom, avg add latency = 44.3809
old dynamic bloom, avg query latency = 50.6485
new dynamic bloom, avg query latency = 43.2186
old avg parallel add latency = 41.678
new avg parallel add latency = 24.5238
old avg parallel hit latency = 14.6322
new avg parallel hit latency = 12.3939
old avg parallel miss latency = 16.7289
new avg parallel miss latency = 12.2134

Tested on a dedicated 64-bit production machine at Facebook. Significant
improvement all around.

Despite now using std::atomic<uint64_t>, quick before-and-after test on
a 32-bit machine (Intel Atom N270, released 2008) shows no regression in
performance, in some cases modest improvement.

--

Performance integration test (synthetic): with DEBUG_LEVEL=0, used
TEST_TMPDIR=/dev/shm ./db_bench --benchmarks=fillrandom,readmissing,readrandom,stats --num=2000000
and optionally with -memtable_whole_key_filtering -memtable_bloom_size_ratio=0.01
300 runs each configuration.

Write throughput change by enabling memtable bloom:
Old locality=0: -3.06%
Old locality=1: -2.37%
New:            -1.50%
conclusion -> seems to substantially close the gap

Readmissing throughput change by enabling memtable bloom:
Old locality=0: +34.47%
Old locality=1: +34.80%
New:            +33.25%
conclusion -> maybe a small new penalty from FP rate

Readrandom throughput change by enabling memtable bloom:
Old locality=0: +31.54%
Old locality=1: +31.13%
New:            +30.60%
conclusion -> maybe also from FP rate (after memtable flush)

--

Another conclusion we can draw from this new implementation is that the
existing 32-bit hash function is not inherently crippling the Bloom
filter speed or accuracy, below about 5 million keys. For speed, the
implementation is essentially the same whether starting with 32-bits or
64-bits of hash; it just determines whether the first multiplication
after fastrange is a pseudorandom expansion or needed re-mix. Note that
this multiplication can occur while memory is fetching.

For accuracy, in a standard configuration, you need about 5 million
keys before you have about a 1.1x FP penalty due to using a
32-bit hash vs. 64-bit:

[~/wormhashing/bloom_simulation_tests] ./foo_gcc_IMPL_CACHE_MUL64_BLOCK_FROM32_any.out $((5 * 1000 * 1000 * 10)) 6 10 $RANDOM 100000000
./foo_gcc_IMPL_CACHE_MUL64_BLOCK_FROM32_any.out time: 2.52069 sampled_fp_rate: 0.0118267 ...
[~/wormhashing/bloom_simulation_tests] ./foo_gcc_IMPL_CACHE_MUL64_BLOCK_any.out $((5 * 1000 * 1000 * 10)) 6 10 $RANDOM 100000000
./foo_gcc_IMPL_CACHE_MUL64_BLOCK_any.out time: 2.43871 sampled_fp_rate: 0.0109059
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5762

Differential Revision: D17214194

Pulled By: pdillinger

fbshipit-source-id: ad9da031772e985fd6b62a0e1db8e81892520595
2019-09-05 14:59:25 -07:00
Peter Dillinger
20dec1401f Copy/split PlainTableBloomV1 from DynamicBloom (refactor) (#5767)
Summary:
DynamicBloom was being used both for memory-only and for on-disk filters, as part of the PlainTable format. To set up enhancements to the memtable Bloom filter, this splits the code into two copies and removes unused features from each copy. Adds test PlainTableDBTest.BloomSchema to ensure no accidental change to that format.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5767

Differential Revision: D17206963

Pulled By: pdillinger

fbshipit-source-id: 6cce8d55305ed0df051b4c58bdc98c8ad81d0553
2019-09-05 10:05:20 -07:00
Shafreeck Sea
ab0645a596 Fix comment of function NotifyCollectTableCollectorsOnFinish (#5738)
Summary:
Signed-off-by: Shafreeck Sea <shafreeck@gmail.com>
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5738

Differential Revision: D17097075

Pulled By: riversand963

fbshipit-source-id: ed01b5f59e8eed262a49abe1f96552842d364af1
2019-08-29 10:57:01 -07:00
anand76
e10570331d Support row cache with batched MultiGet (#5706)
Summary:
This PR adds support for row cache in ```rocksdb::TableCache::MultiGet```.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5706

Test Plan:
1. Unit tests in db_basic_test
2. db_bench results with batch size of 2 (```Get``` is faster than ```MultiGet``` for single key) -
Get -
readrandom   :       3.935 micros/op 254116 ops/sec;   28.1 MB/s (22870998 of 22870999 found)
MultiGet -
multireadrandom :       3.743 micros/op 267190 ops/sec; (24047998 of 24047998 found)

Command used -
TEST_TMPDIR=/dev/shm/multiget numactl -C 10  ./db_bench -use_existing_db=true -use_existing_keys=false -benchmarks="readtorowcache,[read|multiread]random" -write_buffer_size=16777216 -target_file_size_base=4194304 -max_bytes_for_level_base=16777216 -num=12000000 -reads=12000000 -duration=90 -threads=1 -compression_type=none -cache_size=4194304000 -row_cache_size=4194304000 -batch_size=2 -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=131072

Differential Revision: D17086297

Pulled By: anand1976

fbshipit-source-id: 85784378da913e05f1baf31ec1b4e7c9345e7f57
2019-08-28 16:11:56 -07:00
Zhongyi Xie
2f41ecfe75 Refactor trimming logic for immutable memtables (#5022)
Summary:
MyRocks currently sets `max_write_buffer_number_to_maintain` in order to maintain enough history for transaction conflict checking. The effectiveness of this approach depends on the size of memtables. When memtables are small, it may not keep enough history; when memtables are large, this may consume too much memory.
We are proposing a new way to configure memtable list history: by limiting the memory usage of immutable memtables. The new option is `max_write_buffer_size_to_maintain` and it will take precedence over the old `max_write_buffer_number_to_maintain` if they are both set to non-zero values. The new option accounts for the total memory usage of flushed immutable memtables and mutable memtable. When the total usage exceeds the limit, RocksDB may start dropping immutable memtables (which is also called trimming history), starting from the oldest one.
The semantics of the old option actually works both as an upper bound and lower bound. History trimming will start if number of immutable memtables exceeds the limit, but it will never go below (limit-1) due to history trimming.
In order the mimic the behavior with the new option, history trimming will stop if dropping the next immutable memtable causes the total memory usage go below the size limit. For example, assuming the size limit is set to 64MB, and there are 3 immutable memtables with sizes of 20, 30, 30. Although the total memory usage is 80MB > 64MB, dropping the oldest memtable will reduce the memory usage to 60MB < 64MB, so in this case no memtable will be dropped.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5022

Differential Revision: D14394062

Pulled By: miasantreble

fbshipit-source-id: 60457a509c6af89d0993f988c9b5c2aa9e45f5c5
2019-08-23 13:55:34 -07:00
Levi Tamasi
df8c307d63 Revert to storing UncompressionDicts in the cache (#5645)
Summary:
PR https://github.com/facebook/rocksdb/issues/5584 decoupled the uncompression dictionary object from the underlying block data; however, this defeats the purpose of the digested ZSTD dictionary, since the whole point
of the digest is to create it once and reuse it over and over again. This patch goes back to
storing the uncompression dictionary itself in the cache (which should be now safe to do,
since it no longer includes a Statistics pointer), while preserving the rest of the refactoring.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5645

Test Plan: make asan_check

Differential Revision: D16551864

Pulled By: ltamasi

fbshipit-source-id: 2a7e2d34bb16e70e3c816506d5afe1d842057800
2019-08-23 08:27:30 -07:00
Patrick Pei
202942b20c Fix local includes
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5722

Differential Revision: D16908380

fbshipit-source-id: 6a0e3cb2730b08d6012d3d7f31c937f01c399846
2019-08-22 16:21:47 -07:00
Maysam Yabandeh
244e6f2002 Refactor MultiGet names in BlockBasedTable (#5726)
Summary:
To improve code readability, since RetrieveBlock already calls MaybeReadBlockAndLoadToCache, we avoid name similarity of the functions that call RetrieveBlock with MaybeReadBlockAndLoadToCache. The patch thus renames MaybeLoadBlocksToCache to RetrieveMultipleBlock and deletes GetDataBlockFromCache, which contains only two lines.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5726

Differential Revision: D16962535

Pulled By: maysamyabandeh

fbshipit-source-id: 99e8946808ce4eb7857592b9003812e3004f92d6
2019-08-22 08:49:00 -07:00
anand76
9046bdc5d3 Fix MultiGet() bug when whole_key_filtering is disabled (#5665)
Summary:
The batched MultiGet() implementation was not correctly handling bloom filter lookups when whole_key_filtering is disabled. It was incorrectly skipping keys not in the prefix_extractor domain, and not calling transform for keys in domain. This PR fixes both problems by moving the domain check and transformation to the FilterBlockReader.

Tests:
Unit test (confirmed failed before the fix)
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5665

Differential Revision: D16902380

Pulled By: anand1976

fbshipit-source-id: a6be81ad68a6e37134a65246aec7a2c590eccf00
2019-08-21 10:23:23 -07:00
sdong
e1c468d16f Do readahead in VerifyChecksum() (#5713)
Summary:
Right now VerifyChecksum() doesn't do read-ahead. In some use cases, users won't be able to achieve good performance. With this change, by default, RocksDB will do a default readahead, and users will be able to overwrite the readahead size by passing in a ReadOptions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5713

Test Plan: Add a new unit test.

Differential Revision: D16860874

fbshipit-source-id: 0cff0fe79ac855d3d068e6ccd770770854a68413
2019-08-16 16:42:56 -07:00
Zhongyi Xie
e89b1c9c6e add missing check for hash index when calling BlockBasedTableIterator (#5712)
Summary:
Previous PR https://github.com/facebook/rocksdb/pull/3601 added support for making prefix_extractor dynamically mutable. However, there was a missing check for hash index when creating new BlockBasedTableIterator. While the check may be redundant because no other types of IndexReader makes uses of the flag, it is less error-prone to add the missing check so that future index reader implementation will not worry about violating the contract.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5712

Differential Revision: D16842052

Pulled By: miasantreble

fbshipit-source-id: aef11c0ff7a690ed248f5b8fe23481cac486b381
2019-08-16 16:39:49 -07:00
Eli Pozniansky
c2404d9928 Optimizing ApproximateSize to create index iterator just once (#5693)
Summary:
VersionSet::ApproximateSize doesn't need to create two separate index iterators and do binary search for each in BlockBasedTable. So BlockBasedTable::ApproximateSize was added that creates the iterator once and uses it to calculate the data size between start and end keys.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5693

Differential Revision: D16774056

Pulled By: elipoz

fbshipit-source-id: 53ce262e1a057788243bf30cd9b8aa6581df1a18
2019-08-16 14:18:28 -07:00
Levi Tamasi
d92a59b6f2 Fix regression affecting partitioned indexes/filters when cache_index_and_filter_blocks is false (#5705)
Summary:
PR https://github.com/facebook/rocksdb/issues/5298 (and subsequent related patches) unintentionally changed the
semantics of cache_index_and_filter_blocks: historically, this option
only affected the main index/filter block; with the changes, it affects
index/filter partitions as well. This can cause performance issues when
cache_index_and_filter_blocks is false since in this case, partitions are
neither cached nor preloaded (i.e. they are loaded on demand upon each
access). The patch reverts to the earlier behavior, that is, partitions
are cached similarly to data blocks regardless of the value of the above
option.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5705

Test Plan:
make check
./db_bench -benchmarks=fillrandom --statistics --stats_interval_seconds=1 --duration=30 --num=500000000 --bloom_bits=20 --partition_index_and_filters=true --cache_index_and_filter_blocks=false
./db_bench -benchmarks=readrandom --use_existing_db --statistics --stats_interval_seconds=1 --duration=10 --num=500000000 --bloom_bits=20 --partition_index_and_filters=true --cache_index_and_filter_blocks=false --cache_size=8000000000

Relevant statistics from the readrandom benchmark with the old code:

rocksdb.block.cache.index.miss COUNT : 0
rocksdb.block.cache.index.hit COUNT : 0
rocksdb.block.cache.index.add COUNT : 0
rocksdb.block.cache.index.bytes.insert COUNT : 0
rocksdb.block.cache.index.bytes.evict COUNT : 0
rocksdb.block.cache.filter.miss COUNT : 0
rocksdb.block.cache.filter.hit COUNT : 0
rocksdb.block.cache.filter.add COUNT : 0
rocksdb.block.cache.filter.bytes.insert COUNT : 0
rocksdb.block.cache.filter.bytes.evict COUNT : 0

With the new code:

rocksdb.block.cache.index.miss COUNT : 2500
rocksdb.block.cache.index.hit COUNT : 42696
rocksdb.block.cache.index.add COUNT : 2500
rocksdb.block.cache.index.bytes.insert COUNT : 4050048
rocksdb.block.cache.index.bytes.evict COUNT : 0
rocksdb.block.cache.filter.miss COUNT : 2500
rocksdb.block.cache.filter.hit COUNT : 4550493
rocksdb.block.cache.filter.add COUNT : 2500
rocksdb.block.cache.filter.bytes.insert COUNT : 10331040
rocksdb.block.cache.filter.bytes.evict COUNT : 0

Differential Revision: D16817382

Pulled By: ltamasi

fbshipit-source-id: 28a516b0da1f041a03313e0b70b28cf5cf205d00
2019-08-14 18:16:06 -07:00
Yi Zhang
04a849b7b4 Fix compiler error by deleting GetContext default ctor (#5685)
Summary:
When updating compiler version for MyRocks I'm seeing this error with rocksdb:

```
ome/yzha/mysql/mysql-fork2/rocksdb/table/get_context.h:91:3: error: explicitly defaulted default constructor is implicitly deleted
      [-Werror,-Wdefaulted-function-deleted]
  GetContext() = default;
  ^
/home/yzha/mysql/mysql-fork2/rocksdb/table/get_context.h:166:18: note: default constructor of 'GetContext' is implicitly deleted because field
      'tracing_get_id_' of const-qualified type 'const uint64_t' (aka 'const unsigned long') would not be initialized
  const uint64_t tracing_get_id_;
                 ^
```

The error itself is rather self explanatory and makes sense.

Given that no one seems to be using the default ctor (they shouldn't, anyway), I'm deleting it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5685

Differential Revision: D16747712

Pulled By: yizhang82

fbshipit-source-id: 95c0acb958a1ed41154c0047d2e6fce7644de53f
2019-08-12 16:42:10 -07:00
Vijay Nadimpalli
d150e01474 New API to get all merge operands for a Key (#5604)
Summary:
This is a new API added to db.h to allow for fetching all merge operands associated with a Key. The main motivation for this API is to support use cases where doing a full online merge is not necessary as it is performance sensitive. Example use-cases:
1. Update subset of columns and read subset of columns -
Imagine a SQL Table, a row is encoded as a K/V pair (as it is done in MyRocks). If there are many columns and users only updated one of them, we can use merge operator to reduce write amplification. While users only read one or two columns in the read query, this feature can avoid a full merging of the whole row, and save some CPU.
2. Updating very few attributes in a value which is a JSON-like document -
Updating one attribute can be done efficiently using merge operator, while reading back one attribute can be done more efficiently if we don't need to do a full merge.
----------------------------------------------------------------------------------------------------
API :
Status GetMergeOperands(
      const ReadOptions& options, ColumnFamilyHandle* column_family,
      const Slice& key, PinnableSlice* merge_operands,
      GetMergeOperandsOptions* get_merge_operands_options,
      int* number_of_operands)

Example usage :
int size = 100;
int number_of_operands = 0;
std::vector<PinnableSlice> values(size);
GetMergeOperandsOptions merge_operands_info;
db_->GetMergeOperands(ReadOptions(), db_->DefaultColumnFamily(), "k1", values.data(), merge_operands_info, &number_of_operands);

Description :
Returns all the merge operands corresponding to the key. If the number of merge operands in DB is greater than merge_operands_options.expected_max_number_of_operands no merge operands are returned and status is Incomplete. Merge operands returned are in the order of insertion.
merge_operands-> Points to an array of at-least merge_operands_options.expected_max_number_of_operands and the caller is responsible for allocating it. If the status returned is Incomplete then number_of_operands will contain the total number of merge operands found in DB for key.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5604

Test Plan:
Added unit test and perf test in db_bench that can be run using the command:
./db_bench -benchmarks=getmergeoperands --merge_operator=sortlist

Differential Revision: D16657366

Pulled By: vjnadimpalli

fbshipit-source-id: 0faadd752351745224ee12d4ae9ef3cb529951bf
2019-08-06 14:26:44 -07:00
Levi Tamasi
092f417037 Move the uncompression dictionary object out of the block cache (#5584)
Summary:
RocksDB has historically stored uncompression dictionary objects in the block
cache as opposed to storing just the block contents. This neccesitated
evicting the object upon table close. With the new code, only the raw blocks
are stored in the cache, eliminating the need for eviction.

In addition, the patch makes the following improvements:

1) Compression dictionary blocks are now prefetched/pinned similarly to
index/filter blocks.
2) A copy operation got eliminated when the uncompression dictionary is
retrieved.
3) Errors related to retrieving the uncompression dictionary are propagated as
opposed to silently ignored.

Note: the patch temporarily breaks the compression dictionary evicition stats.
They will be fixed in a separate phase.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5584

Test Plan: make asan_check

Differential Revision: D16344151

Pulled By: ltamasi

fbshipit-source-id: 2962b295f5b19628f9da88a3fcebbce5a5017a7b
2019-07-23 16:01:44 -07:00
Eli Pozniansky
6b7fcc0d5f Improve CPU Efficiency of ApproximateSize (part 1) (#5613)
Summary:
1. Avoid creating the iterator in order to call BlockBasedTable::ApproximateOffsetOf(). Instead, directly call into it.
2. Optimize BlockBasedTable::ApproximateOffsetOf() keeps the index block iterator in stack.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5613

Differential Revision: D16442660

Pulled By: elipoz

fbshipit-source-id: 9320be3e918c139b10e758cbbb684706d172e516
2019-07-23 15:34:33 -07:00
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
haoyuhuang
8a008d4170 Block access tracing: Trace referenced key for Get on non-data blocks. (#5548)
Summary:
This PR traces the referenced key for Get for all types of blocks. This is useful when evaluating hybrid row-block caches.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5548

Test Plan: make clean && USE_CLANG=1 make check -j32

Differential Revision: D16157979

Pulled By: HaoyuHuang

fbshipit-source-id: f6327411c9deb74e35e22a35f66cdbae09ab9d87
2019-07-17 13:05:58 -07:00
Levi Tamasi
3bde41b5a3 Move the filter readers out of the block cache (#5504)
Summary:
Currently, when the block cache is used for the filter block, it is not
really the block itself that is stored in the cache but a FilterBlockReader
object. Since this object is not pure data (it has, for instance, pointers that
might dangle, including in one case a back pointer to the TableReader), it's not
really sharable. To avoid the issues around this, the current code erases the
cache entries when the TableReader is closed (which, BTW, is not sufficient
since a concurrent TableReader might have picked up the object in the meantime).
Instead of doing this, the patch moves the FilterBlockReader out of the cache
altogether, and decouples the filter reader object from the filter block.
In particular, instead of the TableReader owning, or caching/pinning the
FilterBlockReader (based on the customer's settings), with the change the
TableReader unconditionally owns the FilterBlockReader, which in turn
owns/caches/pins the filter block. This change also enables us to reuse the code
paths historically used for data blocks for filters as well.

Note:
Eviction statistics for filter blocks are temporarily broken. We plan to fix this in a
separate phase.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5504

Test Plan: make asan_check

Differential Revision: D16036974

Pulled By: ltamasi

fbshipit-source-id: 770f543c5fb4ed126fd1e04bfd3809cf4ff9c091
2019-07-16 13:14:58 -07:00
haoyuhuang
6ca3feed5c Fix -Werror=shadow (#5546)
Summary:
This PR fixes shadow errors.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5546

Test Plan: make clean && make check -j32 && make clean && USE_CLANG=1 make check -j32 && make clean && COMPILE_WITH_ASAN=1 make check -j32

Differential Revision: D16147841

Pulled By: HaoyuHuang

fbshipit-source-id: 1043500d70c134185f537ab4c3900452752f1534
2019-07-08 00:12:43 -07:00
sdong
2de61d9129 Assert get_context not null in BlockBasedTable::Get() (#5542)
Summary:
clang analyze fails after https://github.com/facebook/rocksdb/pull/5514 for this failure:
table/block_based/block_based_table_reader.cc:3450:16: warning: Called C++ object pointer is null
          if (!get_context->SaveValue(
               ^~~~~~~~~~~~~~~~~~~~~~~
1 warning generated.

The reaon is that a branching is added earlier in the function on get_context is null or not, CLANG analyze thinks that it can be null and we make the function call withou the null checking.
Fix the issue by removing the branch and add an assert.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5542

Test Plan: "make all check" passes and CLANG analyze failure goes away.

Differential Revision: D16133988

fbshipit-source-id: d4627d03c4746254cc11926c523931086ccebcda
2019-07-05 12:34:13 -07:00
haoyuhuang
6edc5d0719 Block cache tracing: Associate a unique id with Get and MultiGet (#5514)
Summary:
This PR associates a unique id with Get and MultiGet. This enables us to track how many blocks a Get/MultiGet request accesses. We can also measure the impact of row cache vs block cache.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5514

Test Plan: make clean && COMPILE_WITH_ASAN=1 make check -j32

Differential Revision: D16032681

Pulled By: HaoyuHuang

fbshipit-source-id: 775b05f4440badd58de6667e3ec9f4fc87a0af4c
2019-07-03 19:35:41 -07:00
Yi Wu
662ce62044 Reduce iterator key comparison for upper/lower bound check (2nd attempt) (#5468)
Summary:
This is a second attempt for https://github.com/facebook/rocksdb/issues/5111, with the fix to redo iterate bounds check after `SeekXXX()`. This is because MyRocks may change iterate bounds between seek.

See https://github.com/facebook/rocksdb/issues/5111 for original benchmark result and discussion.

Closes https://github.com/facebook/rocksdb/issues/5463.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5468

Test Plan: Existing rocksdb tests, plus myrocks test `rocksdb.optimizer_loose_index_scans` and `rocksdb.group_min_max`.

Differential Revision: D15863332

fbshipit-source-id: ab4aba5899838591806b8673899bd465f3f53e18
2019-07-02 11:48:46 -07:00
anand76
7259e28d91 MultiGet parallel IO (#5464)
Summary:
Enhancement to MultiGet batching to read data blocks required for keys in a batch in parallel from disk. It uses Env::MultiRead() API to read multiple blocks and reduce latency.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5464

Test Plan:
1. make check
2. make asan_check
3. make asan_crash

Differential Revision: D15911771

Pulled By: anand1976

fbshipit-source-id: 605036b9af0f90ca0020dc87c3a86b4da6e83394
2019-06-30 20:56:04 -07:00
sdong
15fd3be07b LRU Cache to enable mid-point insertion by default (#5508)
Summary:
Mid-point insertion is a useful feature and is mature now. Make it default. Also changed cache_index_and_filter_blocks_with_high_priority=true as default accordingly, so that we won't evict index and filter blocks easier after the change, to avoid too many surprises to users.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5508

Test Plan: Run all existing tests.

Differential Revision: D16021179

fbshipit-source-id: ce8456e8d43b3bfb48df6c304b5290a9d19817eb
2019-06-27 10:20:57 -07:00
haoyuhuang
a8975b6245 Block cache tracer: Do not populate block cache trace record when tracing is disabled. (#5510)
Summary:
This PR makes sure that trace record is not populated when tracing is disabled.

Before this PR:
DB path: [/data/mysql/rocks_regression_tests/OPTIONS-myrocks-40-33-10000000/2019-06-26-13-04-41/db]
readwhilewriting :       9.803 micros/op 1550408 ops/sec;  107.9 MB/s (5000000 of 5000000 found)
Microseconds per read:
Count: 80000000 Average: 9.8045  StdDev: 12.64
Min: 1  Median: 7.5246  Max: 25343
Percentiles: P50: 7.52 P75: 12.10 P99: 37.44 P99.9: 75.07 P99.99: 133.60

After this PR:
DB path: [/data/mysql/rocks_regression_tests/OPTIONS-myrocks-40-33-10000000/2019-06-26-14-08-21/db]
readwhilewriting :       8.723 micros/op 1662882 ops/sec;  115.8 MB/s (5000000 of 5000000 found)
Microseconds per read:
Count: 80000000 Average: 8.7236  StdDev: 12.19
Min: 1  Median: 6.7262  Max: 25229
Percentiles: P50: 6.73 P75: 10.50 P99: 31.54 P99.9: 74.81 P99.99: 132.82
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5510

Differential Revision: D16016428

Pulled By: HaoyuHuang

fbshipit-source-id: 3b3d11e6accf207d18ec2545b802aa01ee65901f
2019-06-27 08:34:08 -07:00
Mike Kolupaev
9dbcda9e3b Fix uninitialized prev_block_offset_ in BlockBasedTableReader (#5507)
Summary:
Found by valgrind_check.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5507

Differential Revision: D16002612

Pulled By: miasantreble

fbshipit-source-id: 13c11c183190e0a0571844635457d434da3ac59a
2019-06-25 23:02:01 -07:00
Mike Kolupaev
b4d7209428 Add an option to put first key of each sst block in the index (#5289)
Summary:
The first key is used to defer reading the data block until this file gets to the top of merging iterator's heap. For short range scans, most files never make it to the top of the heap, so this change can reduce read amplification by a lot sometimes.

Consider the following workload. There are a few data streams (we'll be calling them "logs"), each stream consisting of a sequence of blobs (we'll be calling them "records"). Each record is identified by log ID and a sequence number within the log. RocksDB key is concatenation of log ID and sequence number (big endian). Reads are mostly relatively short range scans, each within a single log. Writes are mostly sequential for each log, but writes to different logs are randomly interleaved. Compactions are disabled; instead, when we accumulate a few tens of sst files, we create a new column family and start writing to it.

So, a typical sst file consists of a few ranges of blocks, each range corresponding to one log ID (we use FlushBlockPolicy to cut blocks at log boundaries). A typical read would go like this. First, iterator Seek() reads one block from each sst file. Then a series of Next()s move through one sst file (since writes to each log are mostly sequential) until the subiterator reaches the end of this log in this sst file; then Next() switches to the next sst file and reads sequentially from that, and so on. Often a range scan will only return records from a small number of blocks in small number of sst files; in this case, the cost of initial Seek() reading one block from each file may be bigger than the cost of reading the actually useful blocks.

Neither iterate_upper_bound nor bloom filters can prevent reading one block from each file in Seek(). But this PR can: if the index contains first key from each block, we don't have to read the block until this block actually makes it to the top of merging iterator's heap, so for short range scans we won't read any blocks from most of the sst files.

This PR does the deferred block loading inside value() call. This is not ideal: there's no good way to report an IO error from inside value(). As discussed with siying offline, it would probably be better to change InternalIterator's interface to explicitly fetch deferred value and get status. I'll do it in a separate PR.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5289

Differential Revision: D15256423

Pulled By: al13n321

fbshipit-source-id: 750e4c39ce88e8d41662f701cf6275d9388ba46a
2019-06-24 20:54:04 -07:00
haoyuhuang
705b8eecb4 Add more callers for table reader. (#5454)
Summary:
This PR adds more callers for table readers. These information are only used for block cache analysis so that we can know which caller accesses a block.
1. It renames the BlockCacheLookupCaller to TableReaderCaller as passing the caller from upstream requires changes to table_reader.h and TableReaderCaller is a more appropriate name.
2. It adds more table reader callers in table/table_reader_caller.h, e.g., kCompactionRefill, kExternalSSTIngestion, and kBuildTable.

This PR is long as it requires modification of interfaces in table_reader.h, e.g., NewIterator.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5454

Test Plan: make clean && COMPILE_WITH_ASAN=1 make check -j32.

Differential Revision: D15819451

Pulled By: HaoyuHuang

fbshipit-source-id: b6caa704c8fb96ddd15b9a934b7e7ea87f88092d
2019-06-20 14:31:48 -07:00
Zhongyi Xie
24f73436fb sanitize and limit block_size under 4GB (#5492)
Summary:
`Block::restart_index_`, `Block::restarts_`, and `Block::current_` are defined as uint32_t but  `BlockBasedTableOptions::block_size` is defined as a size_t so user might see corruption as in https://github.com/facebook/rocksdb/issues/5486.
This PR adds a check in `BlockBasedTableFactory::SanitizeOptions` to disallow such configurations.
yiwu-arbug
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5492

Differential Revision: D15914047

Pulled By: miasantreble

fbshipit-source-id: c943f153d967e15aee7f2795730ab8259e2be201
2019-06-20 11:45:08 -07:00
Vijay Nadimpalli
24b118ad98 Combine the read-ahead logic for user reads and compaction reads (#5431)
Summary:
Currently the read-ahead logic for user reads and compaction reads go through different code paths where compaction reads create new table readers and use `ReadaheadRandomAccessFile`. This change is to unify read-ahead logic to use read-ahead in BlockBasedTableReader::InitDataBlock(). As a result of the change  `ReadAheadRandomAccessFile` class and `new_table_reader_for_compaction_inputs` option will no longer be used.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5431

Test Plan:
make check

Here is the benchmarking - https://gist.github.com/vjnadimpalli/083cf423f7b6aa12dcdb14c858bc18a5

Differential Revision: D15772533

Pulled By: vjnadimpalli

fbshipit-source-id: b71dca710590471ede6fb37553388654e2e479b9
2019-06-19 14:10:46 -07:00
Levi Tamasi
5355e527d9 Make the 'block read count' performance counters consistent (#5484)
Summary:
The patch brings the semantics of per-block-type read performance
context counters in sync with the generic block_read_count by only
incrementing the counter if the block was actually read from the file.
It also fixes index_block_read_count, which fell victim to the
refactoring in PR https://github.com/facebook/rocksdb/issues/5298.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5484

Test Plan: Extended the unit tests.

Differential Revision: D15887431

Pulled By: ltamasi

fbshipit-source-id: a3889759d0ac5759d56625d692cd828d1b9207a6
2019-06-18 19:03:24 -07:00
Levi Tamasi
d0c6aea192 Revert to respecting only the read_tier read option for index blocks (#5481)
Summary:
PR https://github.com/facebook/rocksdb/issues/5298 subtly changed how read options are applied to the index block
during a Get, MultiGet, or iteration. Earlier, only the read_tier option
applied to the index block read; since PR https://github.com/facebook/rocksdb/issues/5298, fill_cache and
verify_checksums also have an effect. This patch restores the earlier
behavior to prevent surprise memory increases for clients due to the
index block not being cached.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5481

Test Plan: make check

Differential Revision: D15883082

Pulled By: ltamasi

fbshipit-source-id: 9a065ec3a6db5a365cf6dd5e95190a20c5756356
2019-06-18 15:02:09 -07:00
haoyuhuang
7a8d7358bb Integrate block cache tracer in block based table reader. (#5441)
Summary:
This PR integrates the block cache tracer into block based table reader. The tracer will write the block cache accesses using the trace_writer. The tracer is null in this PR so that nothing will be logged.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5441

Differential Revision: D15772029

Pulled By: HaoyuHuang

fbshipit-source-id: a64adb92642cd23222e0ba8b10d86bf522b42f9b
2019-06-14 17:40:31 -07:00
haoyuhuang
bb4178066d Integrate block cache tracer into db_impl (#5433)
Summary:
This PR integrates the block cache tracer class into db_impl.cc.
db_impl.cc contains a member variable of AtomicBlockCacheTraceWriter class and passes its reference to the block_based_table_reader.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5433

Differential Revision: D15728016

Pulled By: HaoyuHuang

fbshipit-source-id: 23d5659e8c82d556833dcc1a5558aac8c1f7db71
2019-06-13 15:43:10 -07:00
Levi Tamasi
ba64a4cf52 Revert "Reduce iterator key comparison for upper/lower bound check (#5111)" (#5440)
Summary:
This reverts commit f3a7847598.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5440

Differential Revision: D15765967

Pulled By: ltamasi

fbshipit-source-id: d027fe24132e3729289cd7c01857a7eb449d9dd0
2019-06-11 16:23:41 -07:00
haoyuhuang
5efa0d6b0d Create a BlockCacheLookupContext to enable fine-grained block cache tracing. (#5421)
Summary:
BlockCacheLookupContext only contains the caller for now.
We will trace block accesses at five places:
1. BlockBasedTable::GetFilter.
2. BlockBasedTable::GetUncompressedDict.
3. BlockBasedTable::MaybeReadAndLoadToCache. (To trace access on data, index, and range deletion block.)
4. BlockBasedTable::Get. (To trace the referenced key and whether the referenced key exists in a fetched data block.)
5. BlockBasedTable::MultiGet. (To trace the referenced key and whether the referenced key exists in a fetched data block.)

We create the context at:
1. BlockBasedTable::Get. (kUserGet)
2. BlockBasedTable::MultiGet. (kUserMGet)
3. BlockBasedTable::NewIterator. (either kUserIterator, kCompaction, or external SST ingestion calls this function.)
4. BlockBasedTable::Open. (kPrefetch)
5. Index/Filter::CacheDependencies. (kPrefetch)
6. BlockBasedTable::ApproximateOffsetOf. (kCompaction or kUserApproximateSize).

I loaded 1 million key-value pairs into the database and ran the readrandom benchmark with a single thread. I gave the block cache 10 GB to make sure all reads hit the block cache after warmup. The throughput is comparable.
Throughput of this PR: 231334 ops/s.
Throughput of the master branch: 238428 ops/s.

Experiment setup:
RocksDB:    version 6.2
Date:       Mon Jun 10 10:42:51 2019
CPU:        24 * Intel Core Processor (Skylake)
CPUCache:   16384 KB
Keys:       20 bytes each
Values:     100 bytes each (100 bytes after compression)
Entries:    1000000
Prefix:    20 bytes
Keys per prefix:    0
RawSize:    114.4 MB (estimated)
FileSize:   114.4 MB (estimated)
Write rate: 0 bytes/second
Read rate: 0 ops/second
Compression: NoCompression
Compression sampling rate: 0
Memtablerep: skip_list
Perf Level: 1

Load command: ./db_bench --benchmarks="fillseq" --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 --statistics --cache_index_and_filter_blocks --cache_size=10737418240 --disable_auto_compactions=1 --disable_wal=1 --compression_type=none --min_level_to_compress=-1 --compression_ratio=1 --num=1000000

Run command: ./db_bench --benchmarks="readrandom,stats" --use_existing_db --threads=1 --duration=120 --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 --statistics --cache_index_and_filter_blocks --cache_size=10737418240 --disable_auto_compactions=1 --disable_wal=1 --compression_type=none --min_level_to_compress=-1 --compression_ratio=1 --num=1000000 --duration=120

TODOs:
1. Create a caller for external SST file ingestion and differentiate the callers for iterator.
2. Integrate tracer to trace block cache accesses.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5421

Differential Revision: D15704258

Pulled By: HaoyuHuang

fbshipit-source-id: 4aa8a55f8cb1576ffb367bfa3186a91d8f06d93a
2019-06-10 15:33:27 -07:00
anand76
63ace8ef0e Reuse data block iterator in BlockBasedTableReader::MultiGet() (#5314)
Summary:
Instead of creating a new DataBlockIterator for every key in a MultiGet batch, reuse it if the next key is in the same block. This results in a small 1-2% cpu improvement.

TEST_TMPDIR=/dev/shm/multiget numactl -C 10  ./db_bench.tmp -use_existing_db=true -benchmarks="readseq,multireadrandom" -write_buffer_size=4194304 -target_file_size_base=4194304 -max_bytes_for_level_base=16777216 -num=12000000 -reads=12000000 -duration=90 -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

Without the change -
multireadrandom :       3.066 micros/op 326122 ops/sec; (29375968 of 29375968 found)

With the change -
multireadrandom :       3.003 micros/op 332945 ops/sec; (29983968 of 29983968 found)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5314

Differential Revision: D15742108

Pulled By: anand1976

fbshipit-source-id: 220fb0b8eea9a0d602ddeb371528f7af7936d771
2019-06-10 13:31:19 -07:00
Levi Tamasi
0f48e56f96 Revert to checking the upper bound on a per-key basis in BlockBasedTableIterator (#5428)
Summary:
PR #5111 reduced the number of key comparisons when iterating with
upper/lower bounds; however, this caused a regression for MyRocks.
Reverting to the previous behavior in BlockBasedTableIterator as a hotfix.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5428

Differential Revision: D15721038

Pulled By: ltamasi

fbshipit-source-id: 5450106442f1763bccd17f6cfd648697f2ae8b6c
2019-06-07 15:17:05 -07:00
Zhongyi Xie
d68f9f4580 simplify include directive involving inttypes (#5402)
Summary:
When using `PRIu64` type of printf specifier, current code base does the following:
```
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
```
However, this can be simplified to
```
#include <cinttypes>
```
as long as flag `-std=c++11` is used.
This should solve issues like https://github.com/facebook/rocksdb/issues/5159
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5402

Differential Revision: D15701195

Pulled By: miasantreble

fbshipit-source-id: 6dac0a05f52aadb55e9728038599d3d2e4b59d03
2019-06-06 13:56:07 -07:00
Levi Tamasi
bee2f48a66 Refactor the handling of cache related counters and statistics (#5408)
Summary:
The patch cleans up the handling of cache hit/miss/insertion related
performance counters, get context counters, and statistics by
eliminating some code duplication and factoring out the affected logic
into separate methods. In addition, it makes the semantics of cache hit
metrics more consistent by changing the code so that accessing a
partition of partitioned indexes/filters through a pinned reference no
longer counts as a cache hit.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5408

Differential Revision: D15610883

Pulled By: ltamasi

fbshipit-source-id: ee749c18965077aca971d8f8bee8b24ed8fa76f1
2019-06-06 11:36:40 -07:00
Yanqin Jin
340ed4fac7 Add support for timestamp in Get/Put (#5079)
Summary:
It's useful to be able to (optionally) associate key-value pairs with user-provided timestamps. This PR is an early effort towards this goal and continues the work of facebook#4942. A suite of new unit tests exist in DBBasicTestWithTimestampWithParam. Support for timestamp requires the user to provide timestamp as a slice in `ReadOptions` and `WriteOptions`. All timestamps of the same database must share the same length, format, etc. The format of the timestamp is the same throughout the same database, and the user is responsible for providing a comparator function (Comparator) to order the <key, timestamp> tuples. Once created, the format and length of the timestamp cannot change (at least for now).

Test plan (on devserver):
```
$COMPILE_WITH_ASAN=1 make -j32 all
$./db_basic_test --gtest_filter=Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/*
$make check
```
All tests must pass.

We also run the following db_bench tests to verify whether there is regression on Get/Put while timestamp is not enabled.
```
$TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillseq,readrandom -num=1000000
$TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillrandom -num=1000000
```
Repeat for 6 times for both versions.

Results are as follows:
```
|        | readrandom | fillrandom |
| master | 16.77 MB/s | 47.05 MB/s |
| PR5079 | 16.44 MB/s | 47.03 MB/s |
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5079

Differential Revision: D15132946

Pulled By: riversand963

fbshipit-source-id: 833a0d657eac21182f0f206c910a6438154c742c
2019-06-05 23:10:47 -07:00
haoyuhuang
349db90497 Make GetEntryFromCache a member function. (#5394)
Summary:
The commit makes GetEntryFromCache become a member function. It also makes all its callers become member functions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5394

Differential Revision: D15579222

Pulled By: HaoyuHuang

fbshipit-source-id: 07509c42ee9022dcded54950012bd3bd562aa1ae
2019-06-03 12:34:59 -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
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
Levi Tamasi
a3609b7dde Improve const correctness in BlockBasedTableReader (#5383)
Summary:
Many methods are passing around pointers to non-const objects when in fact
they do not/should not modify said objects. The patch makes the semantics
clearer and also helps from a thread safety point-of-view by changing some
pointers to pointers-to-const and marking some instance methods as const.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5383

Differential Revision: D15562770

Pulled By: ltamasi

fbshipit-source-id: 89361dadbb8b25bbe54d17e8da28fee24a2419af
2019-05-31 11:41:35 -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
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
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
eb7647ee6c Add comments t get_context.h
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5353

Differential Revision: D15497912

Pulled By: anand1976

fbshipit-source-id: 72cff2465ca342aa810f925be5a7016b938aa416
2019-05-24 13:31:05 -07:00
Vijay Nadimpalli
f66026c8c7 Comments for BlockBasedTable
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5352

Differential Revision: D15498477

Pulled By: vjnadimpalli

fbshipit-source-id: 08a981521848433362a56ac521c7fb83c7dd7b2a
2019-05-24 12:35:25 -07:00
Levi Tamasi
98094f6cac Add some comments for BlockContents
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5354

Differential Revision: D15496645

Pulled By: ltamasi

fbshipit-source-id: 1282b1ce11fbc412d3d87b2688fd0586e7bb6b85
2019-05-24 11:20:09 -07:00
Siying Dong
38a06aa225 Improve comments of classes for PlainTable (#5339)
Summary:
Simply add some comments.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5339

Differential Revision: D15485315

Pulled By: siying

fbshipit-source-id: 4594b1c4c967e6bd08aa7fa08a37df3481df1938
2019-05-23 16:51:44 -07:00
Levi Tamasi
40aa520a51 Add class comment for BlockFetcher
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5337

Differential Revision: D15482289

Pulled By: ltamasi

fbshipit-source-id: 8639ca78c1b8dfcc337a742d4d81d5752f12545f
2019-05-23 14:22:26 -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
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
Mike Kolupaev
6a6aef25c1 Fix crash in BlockBasedTableIterator::Seek() (#5291)
Summary:
https://github.com/facebook/rocksdb/pull/5256 broke it: `block_iter_.user_key()` may not be valid even if `block_iter_points_to_real_block_` is true. E.g. if there was an IO error or Status::Incomplete.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5291

Differential Revision: D15273324

Pulled By: al13n321

fbshipit-source-id: 442e5b09f9884a58f92a6ac1ca93af719c219886
2019-05-10 12:40:57 -07:00
Levi Tamasi
f0bf3bf34b Turn CachableEntry into a proper resource handle (#5252)
Summary:
CachableEntry is used in a variety of contexts: it may refer to a cached
object (i.e. an object in the block cache), an owned object, or an
unowned object; also, in some cases (most notably with iterators), the
responsibility of managing the pointed-to object gets handed off to
another object. Each of the above scenarios have different implications
for the lifecycle of the referenced object. For the most part, the patch
does not change the lifecycle of managed objects; however, it makes
these relationships explicit, and it also enables us to eliminate some
hacks and accident-prone code around releasing cache handles and
deleting/cleaning up objects. (The only places where the patch changes
how an objects are managed are the partitions of partitioned indexes and
filters.)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5252

Differential Revision: D15101358

Pulled By: ltamasi

fbshipit-source-id: 9eb59e9ae5a7230e3345789762d0ba1f189485be
2019-05-10 11:57:49 -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
Zhongyi Xie
eea1cad850 avoid updating index type during iterator creation (#5288)
Summary:
Right now there is a potential race condition where two threads are created to iterate through the DB (https://gist.github.com/miasantreble/88f5798a397ee7cb8e7baff9db2d9e85).  The problem is that in `BlockBasedTable::NewIndexIterator`, if both threads failed to find index_reader from block cache, they will call `CreateIndexReader->UpdateIndexType()` which creates a race to update `index_type` in the shared rep_ object. By checking the code, we realize the index type is always populated by `PrefetchIndexAndFilterBlocks` during the table `Open` call, so there is no need to update index type every time during iterator creation. This PR attempts to fix the race condition by removing the unnecessary call to `UpdateIndexType`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5288

Differential Revision: D15252509

Pulled By: miasantreble

fbshipit-source-id: 6e3258652121d5c76d267f7ac457e15c5e84756e
2019-05-07 20:20:40 -07:00
Maysam Yabandeh
6a40ee5eb1 Refresh snapshot list during long compactions (2nd attempt) (#5278)
Summary:
Part of compaction cpu goes to processing snapshot list, the larger the list the bigger the overhead. Although the lifetime of most of the snapshots is much shorter than the lifetime of compactions, the compaction conservatively operates on the list of snapshots that it initially obtained. This patch allows the snapshot list to be updated via a callback if the compaction is taking long. This should let the compaction to continue more efficiently with much smaller snapshot list.
For simplicity, to avoid the feature is disabled in two cases: i) When more than one sub-compaction are sharing the same snapshot list, ii) when Range Delete is used in which the range delete aggregator has its own copy of snapshot list.
This fixes the reverted https://github.com/facebook/rocksdb/pull/5099 issue with range deletes.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5278

Differential Revision: D15203291

Pulled By: maysamyabandeh

fbshipit-source-id: fa645611e606aa222c7ce53176dc5bb6f259c258
2019-05-03 17:30:22 -07:00
Zhongyi Xie
5d27d65bef multiget: fix memory issues due to vector auto resizing (#5279)
Summary:
This PR fixes three memory issues found by ASAN
* in db_stress, the key vector for MultiGet is created using `emplace_back` which could potentially invalidates references to the underlying storage (vector<string>) due to auto resizing. Fix by calling reserve in advance.
* Similar issue in construction of GetContext autovector in version_set.cc
* In multiget_context.h use T[] specialization for unique_ptr that holds a char array
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5279

Differential Revision: D15202893

Pulled By: miasantreble

fbshipit-source-id: 14cc2cda0ed64d29f2a1e264a6bfdaa4294ee75d
2019-05-03 15:58:43 -07:00
Siying Dong
4479dff208 Reduce binary search when reseek into the same data block (#5256)
Summary:
Right now, when Seek() is called again, RocksDB always does a binary search against the files and index blocks, even if they end up with the same file/block. Improve it as following:
1. in LevelIterator, reseek first try to check the boundary of the current file. If it falls into the same file, skip the binary search to find the file
2. in block based table iterator, reseek skip to reseek the iterator block if the seek key is larger than the current key and lower than the index key (boundary of the current block and the next block).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5256

Differential Revision: D15105072

Pulled By: siying

fbshipit-source-id: 39634bdb4a881082451fa39cecd7ecf12160bf80
2019-05-01 14:26:30 -07:00
Maysam Yabandeh
521d234bda Revert snap_refresh_nanos feature (#5269)
Summary:
Our daily stress tests are failing after this feature. Reverting temporarily until we figure the reason for test failures.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5269

Differential Revision: D15151285

Pulled By: maysamyabandeh

fbshipit-source-id: e4002b99690a97df30d4b4b58bf0f61e9591bc6e
2019-05-01 10:07:30 -07:00
Andrew Kryczka
b02d0c238d Init compression dict handle before reading meta-blocks (#5267)
Summary:
At least one of the meta-block loading functions (`ReadRangeDelBlock`)
uses the same block reading function (`NewDataBlockIterator`) as data
block reads, which means it uses the dictionary handle. However, the
dictionary handle was uninitialized while reading meta-blocks, causing
readers to receive an error. This situation was only noticed when
`cache_index_and_filter_blocks=true`.

This PR initializes the handle to null while reading meta-blocks to
prevent the error. It also adds support to `db_stress` /
`db_crashtest.py` for `cache_index_and_filter_blocks`.

Fixes #5263.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5267

Differential Revision: D15149264

Pulled By: maysamyabandeh

fbshipit-source-id: 991d38a306c62db5976778bfb050fa3cd4a0671b
2019-04-30 09:50:49 -07:00
Sagar Vemuri
3548e4220d Improve explicit user readahead performance (#5246)
Summary:
Improve the iterators performance when the user explicitly sets the readahead size via `ReadOptions.readahead_size`.

1. Stop creating new table readers when the user explicitly sets readahead size.
2. Make use of an internal buffer based on `FilePrefetchBuffer` instead of using `ReadaheadRandomAccessFileReader`, to handle the user readahead requests (for both buffered and direct io cases).
3. Add `readahead_size` to db_bench.

**Benchmarks:**
https://gist.github.com/sagar0/53693edc320a18abeaeca94ca32f5737

For 1 MB readahead, Buffered IO performance improves by 28% and Direct IO performance improves by 50%.
For 512KB readahead, Buffered IO performance improves by 30% and Direct IO performance improves by 67%.

**Test Plan:**
Updated `DBIteratorTest.ReadAhead` test to make sure that:
- no new table readers are created for iterators on setting ReadOptions.readahead_size
- At least "readahead" number of bytes are actually getting read on each iterator read.

TODO later:
- Use similar logic for compactions as well.
- This ties in nicely with #4052 and paves the way for removing ReadaheadRandomAcessFile later.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5246

Differential Revision: D15107946

Pulled By: sagar0

fbshipit-source-id: 2c1149729ca7d779e4e8b7710ba6f4e8cbfd3bea
2019-04-26 21:24:10 -07:00
Maysam Yabandeh
506e8448be Refresh snapshot list during long compactions (#5099)
Summary:
Part of compaction cpu goes to processing snapshot list, the larger the list the bigger the overhead. Although the lifetime of most of the snapshots is much shorter than the lifetime of compactions, the compaction conservatively operates on the list of snapshots that it initially obtained. This patch allows the snapshot list to be updated via a callback if the compaction is taking long. This should let the compaction to continue more efficiently with much smaller snapshot list.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5099

Differential Revision: D15086710

Pulled By: maysamyabandeh

fbshipit-source-id: 7649f56c3b6b2fb334962048150142a3bf9c1a12
2019-04-25 18:17:22 -07:00
Yuchi Chen
78a6e07c83 Fix compilation errors for 32bits/LITE/ios build. (#5220)
Summary:
When I build RocksDB for 32bits/LITE/iOS environment, some errors like the following.

`
table/block_based_table_reader.cc:971:44: error: implicit conversion loses integer precision: 'uint64_t'
      (aka 'unsigned long long') to 'size_t' (aka 'unsigned long') [-Werror,-Wshorten-64-to-32]
    size_t block_size = props_block_handle.size();
           ~~~~~~~~~~   ~~~~~~~~~~~~~~~~~~~^~~~~~

./util/file_reader_writer.h:177:8: error: private field 'env_' is not used [-Werror,-Wunused-private-field]
  Env* env_;
       ^
`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5220

Differential Revision: D15023481

Pulled By: siying

fbshipit-source-id: 1b5d121d3016f2b0a8a9a2cc1bd638479357f9f7
2019-04-22 16:02:16 -07:00
Mike Kolupaev
df38c1ce66 Add BlockBasedTableOptions::index_shortening (#5174)
Summary:
Introduce BlockBasedTableOptions::index_shortening to give users control on which key shortening techniques to be used in building index blocks. Before this patch, both separators and successor keys where shortened in indexes. With this patch, the default is set to kShortenSeparators to only shorten the separators. Since each index block has many separators and only one successor (last key), the change should not have negative impact on index block size. However it should prevent many unnecessary block loads where due to approximation introduced by shorted successor, seek would land us to the previous block and then fix it by moving to the next one.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5174

Differential Revision: D14884185

Pulled By: al13n321

fbshipit-source-id: 1b08bc8c03edcf09b6b8c16e9a7eea08ad4dd534
2019-04-22 08:20:35 -07:00
anand76
5265c5709e Remove a couple of non-public includes from public header file (#5219)
Summary:
Cleanup a couple of stray includes left by #5011.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5219

Differential Revision: D15007244

Pulled By: anand1976

fbshipit-source-id: 15ca1d4f977b5b60e99df3bfb8fc3db217d19bdd
2019-04-19 11:10:33 -07:00
Sagar Vemuri
efa948741c Use creation_time or mtime when file_creation_time=0 (#5184)
Summary:
We found an issue in Periodic Compactions (introduced in #5166) where files were not being picked up for compactions as all the SST files created with older versions of RocksDB have `file_creation_time` as 0. (Note that `file_creation_time` is a new table property introduced in #5166).

To address this, Periodic compactions now fall back to looking at the `creation_time` table property or the file's modification time (as given by the Env) when `file_creation_time` table property is found to be 0.

Here how the file's modification time (and, in turn, the file age) is computed now:
1. Use `file_creation_time` table property if it is > 0.
1. If not, then use `creation_time` table property if it is > 0.
1. If not, then use file's mtime stat metadata given by the underlying Env.
Don't consider the file at all for compaction if the modification time cannot be correctly determined based on the above conditions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5184

Differential Revision: D14907795

Pulled By: sagar0

fbshipit-source-id: 4bb2f3631f9a3e04470c674a1d13544584e1e56c
2019-04-18 22:39:34 -07:00
Siying Dong
992dfc7811 Introduce InternalIteratorBase::NextAndGetResult() (#5197)
Summary:
In long scans, virtual function calls of Next(), Valid(), key() and value() are not trivial. By introducing NextAndGetResult(), Some of the Next(), Valid() and key() calls are consolidated into one virtual function call to reduce CPU.
Also did some inline tricks and add some "final" randomly in some functions. Even without the "final" annotation, most Next() calls are inlined with -O3, but sometimes with a final it is inlined by O2 too. It doesn't hurt to add those final annotations.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5197

Differential Revision: D14945977

Pulled By: siying

fbshipit-source-id: 7003969f9a5f1d5717f0bda503b91d19ba75ed88
2019-04-18 11:12:39 -07:00
Fosco Marotto
6c2bf9e916 Add copyright headers per FB open-source checkup tool. (#5199)
Summary:
internal task: T35568575
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5199

Differential Revision: D14962794

Pulled By: gfosco

fbshipit-source-id: 93838ede6d0235eaecff90d200faed9a8515bbbe
2019-04-18 10:55:01 -07:00
Yanqin Jin
d9280ff2d2 Add back NewEmptyIterator (#5203)
Summary:
#4905 removed the implementation of `NewEmptyIterator` but kept its
declaration in the public header. This breaks some systems that depend on
RocksDB if the systems use `NewEmptyIterator`. Therefore, add it back to fix. cc maysamyabandeh please remind me if I miss anything here. Thanks
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5203

Differential Revision: D14968382

Pulled By: riversand963

fbshipit-source-id: 5fb86e99c8cfaf9f7a9473cdb1355d7558ff6e01
2019-04-16 20:28:05 -07:00
yiwu-arbug
f1239d5f10 Avoid per-key upper bound check in BlockBasedTableIterator (#5142)
Summary:
This is second attempt for #5101. Original commit message:
`BlockBasedTableIterator` avoid reading next block on `Next()` if it detects the iterator will be out of bound, by checking against index key. The optimization was added in #2239, and by the time it only check the bound per block. It seems later change make it a per-key check, which introduce unnecessary key comparisons.

This patch come with two fixes:

Fix 1: To optimize checking for bounds, we need comparing the bounds with index key as well. However BlockBasedTableIterator doesn't know whether its index iterator is internally using user keys or internal keys. The patch fixes that by extending InternalIterator with a user_key() function that is overridden by In IndexBlockIter.

Fix 2: In #5101 we return `IsOutOfBound()=true` when block index key is out of bound. But the index key can be larger than smallest key of the next file on the level. That file can be within upper bound and should not be filtered out.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5142

Differential Revision: D14907113

Pulled By: siying

fbshipit-source-id: ac95775c5b4e7b700f76ab43e39f45402c98fbfb
2019-04-16 11:37:47 -07:00
Yanqin Jin
3189398c00 Fix bugs detected by clang analyzer (#5185)
Summary:
as titled. False positive included, fixed anyway to make the check
pass.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5185

Differential Revision: D14909384

Pulled By: riversand963

fbshipit-source-id: dc5177e72b1929ccfd6175a60e2cd7bdb9bd80f3
2019-04-12 10:45:56 -07:00
anand76
fefd4b98c5 Introduce a new MultiGet batching implementation (#5011)
Summary:
This PR introduces a new MultiGet() API, with the underlying implementation grouping keys based on SST file and batching lookups in a file. The reason for the new API is twofold - the definition allows callers to allocate storage for status and values on stack instead of std::vector, as well as return values as PinnableSlices in order to avoid copying, and it keeps the original MultiGet() implementation intact while we experiment with batching.

Batching is useful when there is some spatial locality to the keys being queries, as well as larger batch sizes. The main benefits are due to -
1. Fewer function calls, especially to BlockBasedTableReader::MultiGet() and FullFilterBlockReader::KeysMayMatch()
2. Bloom filter cachelines can be prefetched, hiding the cache miss latency

The next step is to optimize the binary searches in the level_storage_info, index blocks and data blocks, since we could reduce the number of key comparisons if the keys are relatively close to each other. The batching optimizations also need to be extended to other formats, such as PlainTable and filter formats. This also needs to be added to db_stress.

Benchmark results from db_bench for various batch size/locality of reference combinations are given below. Locality was simulated by offsetting the keys in a batch by a stride length. Each SST file is about 8.6MB uncompressed and key/value size is 16/100 uncompressed. To focus on the cpu benefit of batching, the runs were single threaded and bound to the same cpu to eliminate interference from other system events. The results show a 10-25% improvement in micros/op from smaller to larger batch sizes (4 - 32).

Batch   Sizes

1        | 2        | 4         | 8      | 16  | 32

Random pattern (Stride length 0)
4.158 | 4.109 | 4.026 | 4.05 | 4.1 | 4.074        - Get
4.438 | 4.302 | 4.165 | 4.122 | 4.096 | 4.075 - MultiGet (no batching)
4.461 | 4.256 | 4.277 | 4.11 | 4.182 | 4.14        - MultiGet (w/ batching)

Good locality (Stride length 16)
4.048 | 3.659 | 3.248 | 2.99 | 2.84 | 2.753
4.429 | 3.728 | 3.406 | 3.053 | 2.911 | 2.781
4.452 | 3.45 | 2.833 | 2.451 | 2.233 | 2.135

Good locality (Stride length 256)
4.066 | 3.786 | 3.581 | 3.447 | 3.415 | 3.232
4.406 | 4.005 | 3.644 | 3.49 | 3.381 | 3.268
4.393 | 3.649 | 3.186 | 2.882 | 2.676 | 2.62

Medium locality (Stride length 4096)
4.012 | 3.922 | 3.768 | 3.61 | 3.582 | 3.555
4.364 | 4.057 | 3.791 | 3.65 | 3.57 | 3.465
4.479 | 3.758 | 3.316 | 3.077 | 2.959 | 2.891

dbbench command used (on a DB with 4 levels, 12 million keys)-
TEST_TMPDIR=/dev/shm numactl -C 10  ./db_bench.tmp -use_existing_db=true -benchmarks="readseq,multireadrandom" -write_buffer_size=4194304 -target_file_size_base=4194304 -max_bytes_for_level_base=16777216 -num=12000000 -reads=12000000 -duration=90 -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
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5011

Differential Revision: D14348703

Pulled By: anand1976

fbshipit-source-id: 774406dab3776d979c809522a67bedac6c17f84b
2019-04-11 14:28:26 -07:00
Sagar Vemuri
d3d20dcdca Periodic Compactions (#5166)
Summary:
Introducing Periodic Compactions.

This feature allows all the files in a CF to be periodically compacted. It could help in catching any corruptions that could creep into the DB proactively as every file is constantly getting re-compacted.  And also, of course, it helps to cleanup data older than certain threshold.

- Introduced a new option `periodic_compaction_time` to control how long a file can live without being compacted in a CF.
- This works across all levels.
- The files are put in the same level after going through the compaction. (Related files in the same level are picked up as `ExpandInputstoCleanCut` is used).
- Compaction filters, if any, are invoked as usual.
- A new table property, `file_creation_time`, is introduced to implement this feature. This property is set to the time at which the SST file was created (and that time is given by the underlying Env/OS).

This feature can be enabled on its own, or in conjunction with `ttl`. It is possible to set a different time threshold for the bottom level when used in conjunction with ttl. Since `ttl` works only on 0 to last but one levels, you could set `ttl` to, say, 1 day, and `periodic_compaction_time` to, say, 7 days. Since `ttl < periodic_compaction_time` all files in last but one levels keep getting picked up based on ttl, and almost never based on periodic_compaction_time. The files in the bottom level get picked up for compaction based on `periodic_compaction_time`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5166

Differential Revision: D14884441

Pulled By: sagar0

fbshipit-source-id: 408426cbacb409c06386a98632dcf90bfa1bda47
2019-04-10 19:31:18 -07:00
Levi Tamasi
59ef2ba559 Evict the uncompression dictionary from the block cache upon table close (#5150)
Summary:
The uncompression dictionary object has a Statistics pointer that might
dangle if the database closed. This patch evicts the dictionary from the
block cache when a table is closed, similarly to how index and filter
readers are handled.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5150

Differential Revision: D14782422

Pulled By: ltamasi

fbshipit-source-id: 0cec9336c742c479aa92206e04521767f1aa9622
2019-04-04 16:21:12 -07:00
Adam Simpkins
c06c4c01c5 Fix many bugs in log statement arguments (#5089)
Summary:
Annotate all of the logging functions to inform the compiler that these
use printf-style formatting arguments.  This allows the compiler to emit
warnings if the format arguments are incorrect.

This also fixes many problems reported now that format string checking
is enabled.  Many of these are simply mix-ups in the argument type (e.g,
int vs uint64_t), but in several cases the wrong number of arguments
were being passed in which can cause the code to crash.

The primary motivation for this was to fix the log message in
`DBImpl::SwitchMemtable()` which caused a segfault due to an extra %s
format parameter with no argument supplied.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5089

Differential Revision: D14574795

Pulled By: simpkins

fbshipit-source-id: 0921b03f0743652bf4ae21e414ff54b3bb65422a
2019-04-04 12:12:11 -07:00
Zhongyi Xie
26015f3b48 add compression options to table properties (#5081)
Summary:
Since we are planning to use dictionary compression and to use different compression level, it is quite useful to add compression options to TableProperties. For example, in MyRocks, if the feature is available, we can query from information_schema.rocksdb_sst_props to see if all sst files are converted to ZSTD dictionary compressions. Resolves https://github.com/facebook/rocksdb/issues/4992

With this PR, user can query table properties through `GetPropertiesOfAllTables` API and get compression options as std::string:
`window_bits=-14; level=32767; strategy=0; max_dict_bytes=0; zstd_max_train_bytes=0; enabled=0;`
or table_properties->ToString() will also contain it
`# data blocks=1; # entries=13; # deletions=0; # merge operands=0; # range deletions=0; raw key size=143; raw average key size=11.000000; raw value size=39; raw average value size=3.000000; data block size=120; index block size (user-key? 0, delta-value? 0)=27; filter block size=0; (estimated) table size=147; filter policy name=N/A; prefix extractor name=nullptr; column family ID=0; column family name=default; comparator name=leveldb.BytewiseComparator; merge operator name=nullptr; property collectors names=[]; SST file compression algo=Snappy; SST file compression options=window_bits=-14; level=32767; strategy=0; max_dict_bytes=0; zstd_max_train_bytes=0; enabled=0; ; creation time=1552946632; time stamp of earliest key=1552946632;`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5081

Differential Revision: D14716692

Pulled By: miasantreble

fbshipit-source-id: 7d2f2cf84e052bff876e71b4212cfdebf5be32dd
2019-04-02 14:52:34 -07:00
Siying Dong
ebcc8ae1d3 Revert "Avoid per-key upper bound check in BlockBasedTableIterator (#5101)" (#5132)
Summary:
This reverts commit f29dc1b906.

In BlockBasedTableIterator, index_iter_->key() is sometimes a user key, so it is wrong to call ExtractUserKey() against it. This is a bug introduced by #5101.
Temporarily revert the diff to keep the branch clean.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5132

Differential Revision: D14718584

Pulled By: siying

fbshipit-source-id: 0ac55dc9b5dbc18c7809092146bdf7eb9364b9ad
2019-04-02 10:00:38 -07:00
Remington Brasga
127a850beb Fix arena allocation size in NewEmptyInternalIterator (#4905)
Summary:
NewEmptyInternalIterator with arena mistakenly used EmptyIterator to allocate the size from area but then initialized it to a totally different object: EmptyInternalIterator. The patch fixes that.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4905

Differential Revision: D14689840

Pulled By: maysamyabandeh

fbshipit-source-id: af64fd8ee93d5a4ad54691c792e5ecc5efabc887
2019-03-29 15:09:35 -07:00
Yi Wu
f29dc1b906 Avoid per-key upper bound check in BlockBasedTableIterator (#5101)
Summary:
`BlockBasedTableIterator` avoid reading next block on `Next()` if it detects the iterator will be out of bound, by checking against index key. The optimization was added in #2239, and by the time it only check the bound per block. It seems later change make it a per-key check, which introduce unnecessary key comparisons.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5101

Differential Revision: D14678707

Pulled By: siying

fbshipit-source-id: 2372446116753c7892ea4cec7b4b49ef87ba463e
2019-03-29 13:11:46 -07:00
Siying Dong
89ab1381f8 Apply automatic formatting to some files (#5114)
Summary:
Following files were run through automatic formatter:
db/db_impl.cc
db/db_impl.h
db/db_impl_compaction_flush.cc
db/db_impl_debug.cc
db/db_impl_files.cc
db/db_impl_readonly.h
db/db_impl_write.cc
db/dbformat.cc
db/dbformat.h
table/block.cc
table/block.h
table/block_based_filter_block.cc
table/block_based_filter_block.h
table/block_based_filter_block_test.cc
table/block_based_table_builder.cc
table/block_based_table_reader.cc
table/block_based_table_reader.h
table/block_builder.cc
table/block_builder.h
table/block_fetcher.cc
table/block_prefix_index.cc
table/block_prefix_index.h
table/block_test.cc
table/format.cc
table/format.h

I could easily run all the files, but I don't want people to feel that
I'm doing it for lines of code changes :)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5114

Differential Revision: D14633040

Pulled By: siying

fbshipit-source-id: 3f346cb53bf21e8c10704400da548dfce1e89a52
2019-03-27 16:24:45 -07:00
Yi Wu
d69241586e Fix perf_context.user_key_comparison_count for range scan (#5098)
Summary:
Currently `perf_context.user_key_comparison_count` is bump only in `InternalKeyComparator`. For places user comparator is used directly the counter is not bump. Fixing the majority of it.

Index iterator and filter code also use user comparator directly and don't bump the counter. It is not fixed in this patch.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5098

Differential Revision: D14603753

Pulled By: siying

fbshipit-source-id: 1cd41035644ca9e49b97a51030a5d1e15f5f3cae
2019-03-27 10:34:27 -07:00
Siying Dong
2b4d5ceb47 Remove some "using std::..." from header files. (#5113)
Summary:
The code convention we are following, Google C++ Style, discourage
alias in header files, especially public headers:
https://google.github.io/styleguide/cppguide.html#Aliases
Remove some of them. Might removed some from .cc files as well to be consistent.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5113

Differential Revision: D14633030

Pulled By: siying

fbshipit-source-id: b990edc919d5de60295992284f980195e501d424
2019-03-27 10:28:21 -07:00
Yi Wu
75133b1b6b Fix SstFileReader not able to open ingested file (#5097)
Summary:
Since `SstFileReader` don't know largest seqno of a file, it will fail this check when it open a file with global seqno: ca89ac2ba9/table/block_based_table_reader.cc (L730)
Changes:
* Pass largest_seqno=kMaxSequenceNumber from `SstFileReader` and allow it to bypass the above check.
* `BlockBasedTable::VerifyChecksum` also double check if checksum will match when excluding global seqno (this is to make the new test in sst_table_reader_test pass).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5097

Differential Revision: D14607434

Pulled By: riversand963

fbshipit-source-id: 9008599227c5fccbf9b73fee46b3bf4a1523f023
2019-03-26 10:25:18 -07:00
Yi Wu
7ca9eb7542 Fix BlockBasedTableIterator construction missing index_key_is_full parameter
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/5104

Differential Revision: D14619000

Pulled By: maysamyabandeh

fbshipit-source-id: c2895794a3f31b826c149dcb698c1952dacc2332
2019-03-26 10:13:01 -07:00
Shobhit Dayal
b45b1cde3e Feature for sampling and reporting compressibility (#4842)
Summary:
This is a feature to sample data-block compressibility and and report them as stats. 1 in N (tunable) blocks is sampled for compressibility using two algorithms:
1. lz4 or snappy for fast compression
2. zstd or zlib for slow but higher compression.

The stats are reported to the caller as raw-bytes and compressed-bytes. The block continues to be compressed for storage using the specified CompressionType.

The db_bench_tool how has a command line option for specifying the sampling rate. It's default value is 0 (no sampling). To test the overhead for a certain value, users can compare the performance of db_bench_tool, varying the sampling rate. It is unlikely to have a noticeable impact for high values like 20.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4842

Differential Revision: D13629011

Pulled By: shobhitdayal

fbshipit-source-id: 14ca668bcab6499b2a1734edf848eb62a4f4fafa
2019-03-18 12:15:34 -07:00
Yi Wu
62eb2c23aa Print data block index options to info log (#5039)
Summary:
Print data block index type related options to info log
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5039

Differential Revision: D14387718

Pulled By: miasantreble

fbshipit-source-id: 9df8f82eea83a8344c7d12a712486f656691bc4a
2019-03-08 11:18:45 -08:00
Siying Dong
0920bf4e68 Revert "Remove PlainTable's feature store_index_in_file (#4914)" (#5034)
Summary:
This reverts commit ee1818081f.

We are not ready to deprecate this feature. revert it for now.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5034

Differential Revision: D14287246

Pulled By: siying

fbshipit-source-id: e4beafdeaee1c94364fdaa6ba198218d158339f7
2019-03-01 15:45:45 -08:00
Siying Dong
aef763b6d6 Make statistics's stats_level change thread-safe (#5030)
Summary:
Right now, users can change statistics.stats_level while DB is running, but TSAN may report
data race. We make stats_level_ to be atomic, and access them using accessors.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5030

Differential Revision: D14267519

Pulled By: siying

fbshipit-source-id: 37d7ebeff7a43a406230143422a16af899163f73
2019-03-01 10:42:09 -08:00
Siying Dong
5e298f865b Add two more StatsLevel (#5027)
Summary:
Statistics cost too much CPU for some use cases. Add two stats levels
so that people can choose to skip two types of expensive stats, timers and
histograms.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5027

Differential Revision: D14252765

Pulled By: siying

fbshipit-source-id: 75ecec9eaa44c06118229df4f80c366115346592
2019-02-28 10:27:59 -08:00
Zhongyi Xie
ed995c6a69 add whole key bloom filter support in memtables (#4985)
Summary:
MyRocks calls `GetForUpdate` on `INSERT`, for unique key check, and in almost all cases GetForUpdate returns empty result. For such cases, whole key bloom filter is helpful.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4985

Differential Revision: D14118257

Pulled By: miasantreble

fbshipit-source-id: d35cb7109c62fd5ad541a26968e3a3e16d3e85ea
2019-02-19 12:15:39 -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
c8c8104d7e Dictionary compression for files written by SstFileWriter (#4978)
Summary:
If `CompressionOptions::max_dict_bytes` and/or `CompressionOptions::zstd_max_train_bytes` are set, `SstFileWriter` will now generate files respecting those options.

I refactored the logic a bit for deciding when to use dictionary compression. Previously we plumbed `is_bottommost_level` down to the table builder and used that. However it was kind of confusing in `SstFileWriter`'s context since we don't know what level the file will be ingested to. Instead, now the higher-level callers (e.g., flush, compaction, file writer) are responsible for building the right `CompressionOptions` to give the table builder.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4978

Differential Revision: D14060763

Pulled By: ajkr

fbshipit-source-id: dc802c327896df2b319dc162d6acc82b9cdb452a
2019-02-14 11:23:55 -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
Peter (Stig) Edwards
79496d71ed Increment NUMBER_BLOCK_NOT_COMPRESSED when !GoodCompressionRatio (#4929)
Summary:
See https://github.com/facebook/rocksdb/issues/4884
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4929

Differential Revision: D14028333

Pulled By: sagar0

fbshipit-source-id: eed12bceae85385a34aaa6dd303bf0f53c4c7b06
2019-02-11 17:56:23 -08:00
Yanqin Jin
2d049ab7e8 Checksum properties block for block-based table (#4956)
Summary:
Always enable properties block checksum verification for block-based table. For external SST file ingested with 'write_global_seqno==true', we use 'DecodeEntrySlow' to parse its blocks' contents so that the process will not die upon failing the assertion possibly caused by corruption.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4956

Differential Revision: D14012741

Pulled By: riversand963

fbshipit-source-id: 8b766e6f54b36f8f9e074c0e19e0926ec3cce186
2019-02-11 11:50:01 -08:00
Siying Dong
cf3a671733 Remove cuckoo hash memtable (#4953)
Summary:
Cuckoo Hash is less useful than we initially expected. Remove it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4953

Differential Revision: D13979264

Pulled By: siying

fbshipit-source-id: 2a60afdaa989f045357398b43a1cc5d46f4492ed
2019-02-07 16:15:27 -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
Yanqin Jin
158da7a6ee Verify checksum before ingestion (#4916)
Summary:
before file ingestion (in preparation phase), verify the checksums of
the blocks of the external SST file, including properties block with global
seqno.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4916

Differential Revision: D13863501

Pulled By: riversand963

fbshipit-source-id: dc54697f970e3807832e2460f7228fcc7efe81ee
2019-01-29 17:17:29 -08:00
Siying Dong
ee1818081f Remove PlainTable's feature store_index_in_file (#4914)
Summary:
Store_index_in_file is a less useful feature. To simplify the code to maintain, we are dropping the feature.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4914

Differential Revision: D13791883

Pulled By: siying

fbshipit-source-id: d187c5d662584866103e4b77d09dfb925509ae2e
2019-01-28 12:50:22 -08:00
Siying Dong
f184bee77b PlainTable should avoid copying Get() results from immortal source. (#4924)
Summary:
https://github.com/facebook/rocksdb/pull/4053 avoids memcopy for Get() results if files are immortable
(read-only DB, max_open_files=-1) and the file is ammaped. The same optimization is being applied to PlainTable
here.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4924

Differential Revision: D13827749

Pulled By: siying

fbshipit-source-id: 1f2cbfc530b40ce08ccd53f95f6e78de4d1c2f96
2019-01-25 17:12:19 -08:00
Siying Dong
fc53839bfa Disallow customized hash function in DynamicBloom (#4915)
Summary:
I didn't find where customized hash function is used in DynamicBloom. This can only reduce performance. Remove it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4915

Differential Revision: D13794452

Pulled By: siying

fbshipit-source-id: e38669b11e01444d2d782da11c7decabbd851819
2019-01-24 10:34:30 -08:00
Andrew Kryczka
8ec3e72551 Cache dictionary used for decompressing data blocks (#4881)
Summary:
- If block cache disabled or not used for meta-blocks, `BlockBasedTableReader::Rep::uncompression_dict` owns the `UncompressionDict`. It is preloaded during `PrefetchIndexAndFilterBlocks`.
- If block cache is enabled and used for meta-blocks, block cache owns the `UncompressionDict`, which holds dictionary and digested dictionary when needed. It is never prefetched though there is a TODO for this in the code. The cache key is simply the compression dictionary block handle.
- New stats for compression dictionary accesses in block cache: "BLOCK_CACHE_COMPRESSION_DICT_*" and "compression_dict_block_read_count"
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4881

Differential Revision: D13663801

Pulled By: ajkr

fbshipit-source-id: bdcc54044e180855cdcc57639b493b0e016c9a3f
2019-01-23 18:15:47 -08:00
Andrew Kryczka
27054d837b Call NewDataBlockIterator with correct arguments in DB::Get (#4913)
Summary:
The pointer `get_context` was passed as the value for the boolean argument `index_key_is_full`. Luckily the pointer was always non-null so evaluated to true which is the correct value for the boolean argument. But we were missing out on batch updates to stats since we were not passing anything for the `GetContext*` argument and it defaults to `nullptr`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4913

Differential Revision: D13791449

Pulled By: ajkr

fbshipit-source-id: dbe40bf406c64d34cb5298604145d18b9e0ca9be
2019-01-23 15:39:05 -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
Andrew Kryczka
ace543a815 fix accounting for range tombstones in TableProperties (#4841)
Summary:
- To be consistent with the accounting of other optypes in `TableProperties`, we should count range tombstones in `TableProperties::num_entries` and `TableProperties::num_deletions`.
- Updated assertions in stress test's `OnTableFileCreated` handler to accept files with range tombstones only.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4841

Differential Revision: D13568424

Pulled By: ajkr

fbshipit-source-id: 0139d7806494eda20ece67ec460d2458dbbf6026
2019-01-02 15:08:53 -08:00
Alexander Zinoviev
80bf8975fd Add a new per level counter for block cache hit (#4796)
Summary:
Add a new per level counter for block cache hits, increase it by one on every successful attempt to get an entry from cache.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4796

Differential Revision: D13513688

Pulled By: zinoale

fbshipit-source-id: 104df038f1232e3356e162eb2d8ca138e34a8281
2018-12-21 13:20:05 -08:00
Andrew Kryczka
e0be1bc4f1 fix DeleteRange memory leak for mmap and block cache (#4810)
Summary:
Previously we were cleaning up range tombstone meta-block by calling `ReleaseCachedEntry`, which wouldn't work if `value != nullptr && cache_handle == nullptr`. This happened at least in the case with mmap reads and block cache both enabled. I noticed `NewDataBlockIterator` intends to handle all these cases, so migrated to that instead of `NewUnfragmentedRangeTombstoneIterator`.

Also changed the table-opening logic to fail on `ReadRangeDelBlock` failure, since that can cause data corruption. Added a test case to verify this behavior. Note the test case does not fail on `TryReopen` because failure to preload table handlers is not considered critical. However, it does fail on any read involving that file since it cannot return correct data.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4810

Differential Revision: D13534296

Pulled By: ajkr

fbshipit-source-id: 55dde1111717cea6ec4bf38418daab81ccef3599
2018-12-20 21:59:49 -08:00
DorianZheng
2670fe8c73 Get CompactionJobInfo from CompactFiles
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/4716

Differential Revision: D13207677

Pulled By: ajkr

fbshipit-source-id: d0ccf5a66df6cbb07288b0c5ebad81fd9df3926b
2018-12-13 14:21:24 -08:00
Abhishek Madan
cad248f5c6 Prepare FragmentedRangeTombstoneIterator for use in compaction (#4740)
Summary:
To support the flush/compaction use cases of RangeDelAggregator
in v2, FragmentedRangeTombstoneIterator now supports dropping tombstones
that cannot be read in the compaction output file. Furthermore,
FragmentedRangeTombstoneIterator supports the "snapshot striping" use
case by allowing an iterator to be split by a list of snapshots.
RangeDelAggregatorV2 will use these changes in a follow-up change.

In the process of making these changes, other miscellaneous cleanups
were also done in these files.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4740

Differential Revision: D13287382

Pulled By: abhimadan

fbshipit-source-id: f5aeb03e1b3058049b80c02a558ee48f723fa48c
2018-12-11 12:10:48 -08:00
Anand Ananthabhotla
1b01d23be2 Add PerfContext counters for index/filter block cache stats (#4540)
Summary:
Add counters to track block cache index/filter hits and misses. We currently count aggregate hits and misses, which includes index/filter/data blocks.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4540

Differential Revision: D10459652

Pulled By: anand1976

fbshipit-source-id: 0c59eee7f12f5103dcb6686f0e7995babe63d425
2018-12-07 15:07:56 -08:00
Sagar Vemuri
0463f61837 Refactor BlockBasedTable::Open (#4636)
Summary:
Refactored and simplified `BlockBasedTable::Open` to be similar to `BlockBasedTableBuilder::Finish` as both these functions complement each other. Also added `BlockBasedTableBuilder::WriteFooter` along the way.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4636

Differential Revision: D12933319

Pulled By: sagar0

fbshipit-source-id: 1ff1d02f6d80a63b5ba720a1fc75e71c7344137b
2018-12-07 13:18:44 -08:00
anand76
8d9b4d9741 Fix failure of sst_file_reader_test in LITE mode regression test (#4725)
Summary:
Add a dummy main() in sst_file_reader_test for ROCKSDB_LITE to fix link failure in regression
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4725

Differential Revision: D13252885

Pulled By: anand1976

fbshipit-source-id: 0e22b964815e2bf01aff7d03ed4ae59d44fa86f1
2018-11-29 10:51:41 -08:00
Yi Wu
512a5e3ef8 Fix BlockBasedTable not always using memory allocator if available (#4678)
Summary:
Fix block based table reader not using memory_allocator when allocating index blocks and compression dictionary blocks.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4678

Differential Revision: D13054594

Pulled By: yiwu-arbug

fbshipit-source-id: 379f25bcc665395662511c4f873f4b7b55104ce2
2018-11-28 18:01:24 -08:00
Abhishek Madan
8fe1e06ca0 Clean up FragmentedRangeTombstoneList (#4692)
Summary:
Removed `one_time_use` flag, which removed the need for some
tests, and changed all `NewRangeTombstoneIterator` methods to return
`FragmentedRangeTombstoneIterators`.

These changes also led to removing `RangeDelAggregatorV2::AddUnfragmentedTombstones`
and one of the `MemTableListVersion::AddRangeTombstoneIterators` methods.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4692

Differential Revision: D13106570

Pulled By: abhimadan

fbshipit-source-id: cbab5432d7fc2d9cdfd8d9d40361a1bffaa8f845
2018-11-28 15:29:02 -08:00
Huachao Huang
5e72bc113a Add SstFileReader to read sst files (#4717)
Summary:
A user friendly sst file reader is useful when we want to access sst
files outside of RocksDB. For example, we can generate an sst file
with SstFileWriter and send it to other places, then use SstFileReader
to read the file and process the entries in other ways.

Also rename the original SstFileReader to SstFileDumper because of
name conflict, and seems SstFileDumper is more appropriate for tools.

TODO: there is only a very simple test now, because I want to get some feedback first.
If the changes look good, I will add more tests soon.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4717

Differential Revision: D13212686

Pulled By: ajkr

fbshipit-source-id: 737593383264c954b79e63edaf44aaae0d947e56
2018-11-27 13:02:23 -08:00
Yi Wu
05d9d82181 Revert "Move MemoryAllocator option from Cache to BlockBasedTableOpti… (#4697)
Summary:
…ons (#4676)"

This reverts commit b32d087dbb.

`MemoryAllocator` needs to be with `Cache`, since cache entry can
outlive DB and block based table. The cache needs to hold reference to
memory allocator when deleting cache entry.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4697

Differential Revision: D13133490

Pulled By: yiwu-arbug

fbshipit-source-id: 8ef7e8a51263bfd929f892fd062665ff4ce9ce5a
2018-11-21 11:29:57 -08:00
Abhishek Madan
6bee36a786 Modify FragmentedRangeTombstoneList member layout (#4632)
Summary:
Rather than storing a `vector<RangeTombstone>`, we now store a
`vector<RangeTombstoneStack>` and a `vector<SequenceNumber>`. A
`RangeTombstoneStack` contains the start and end keys of a range tombstone
fragment, and indices into the seqnum vector to indicate which sequence
numbers the fragment is located at. The diagram below illustrates an
example:

```
tombstones_:     [a, b) [c, e) [h, k)
                   | \   /  \   /  |
                   |  \ /    \ /   |
                   v   v      v    v
tombstone_seqs_: [ 5 3 10 7 2 8 6  ]
```

This format allows binary searching the tombstone list to use less key
comparisons, which helps in cases where there are many overlapping
tombstones. Also, this format makes it easier to add DBIter-like
semantics to `FragmentedRangeTombstoneIterator` in the future.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4632

Differential Revision: D13053103

Pulled By: abhimadan

fbshipit-source-id: e8220cc712fcf5be4d602913bb23ace8ea5f8ef0
2018-11-14 17:52:17 -08:00
Siying Dong
b82e57d425 Remove two variables from BlockContents class and don't use class Block for compressed block (#4650)
Summary:
We carry compression type and "cachable" variables for every block in the block cache, while they take well-known values. 8-byte is wasted for each block (2-byte for useful information but it takes 8 bytes because of padding). With this change, these two variables are removed.

The cachable information is only useful in the process of reading the block. We use other information to infer from it. For compressed blocks, the compression type is a part of the block content itself so we can get it from there.

Some code is slightly refactored so that the cachable information can flow better.

Another change is to only use class BlockContents for compressed block, and narrow the class Block to only be used for uncompressed blocks, including blocks in compressed block cache. This can make the Block class less confusing. It also saves tens of bytes for each block in compressed block cache.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4650

Differential Revision: D12969070

Pulled By: siying

fbshipit-source-id: 548b62724e9eb66993026429fd9c7c3acd1f95ed
2018-11-13 17:02:55 -08:00
Yi Wu
b32d087dbb Move MemoryAllocator option from Cache to BlockBasedTableOptions (#4676)
Summary:
Per offline discussion with siying, `MemoryAllocator` and `Cache` should be decouple. The idea is that memory allocator handles memory allocation, while cache handle cache policy.

It is normal that external cache libraries pack couple the two components for better optimization. If we want to integrate with such library in the future, we can make a wrapper of the library implementing both `Cache` and `MemoryAllocator` interface.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4676

Differential Revision: D13047662

Pulled By: yiwu-arbug

fbshipit-source-id: cd42e246d80ab600b4de47d073f7d2db308ce6dd
2018-11-13 13:48:38 -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
Siying Dong
566fc8b994 Black list some valgrind tests (#4642)
Summary:
valgrind tests with 1 thread run too long. To make it shorter, black list some long tests. These are already blacklisted in parallel valgrind tests, but they are not in non-parallel mode
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4642

Differential Revision: D12945237

Pulled By: siying

fbshipit-source-id: 04cf977d435996480fe87aa09f14b17975b74f7d
2018-11-06 14:22:36 -08:00
Bo Hou
cd9404bb77 xxhash 64 support
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/4607

Reviewed By: siying

Differential Revision: D12836696

Pulled By: jsjhoubo

fbshipit-source-id: 7122ccb712d0b0f1cd998aa4477e0da1401bd870
2018-11-01 15:44:06 -07:00
Abhishek Madan
eaaf1a6f05 Promote rocksdb.{deleted.keys,merge.operands} to main table properties (#4594)
Summary:
Since the number of range deletions are reported in
TableProperties, it is confusing to not report the number of merge
operands and point deletions as top-level properties; they are
accessible through the public API, but since they are not the "main"
properties, they do not appear in aggregated table properties, or the
string representation of table properties.

This change promotes those two property keys to
`rocksdb/table_properties.h`, adds corresponding uint64 members for
them, deprecates the old access methods `GetDeletedKeys()` and
`GetMergeOperands()` (though they are still usable for now), and removes
`InternalKeyPropertiesCollector`. The property key strings are the same
as before this change, so this should be able to read DBs written from older
versions (though I haven't tested this yet).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4594

Differential Revision: D12826893

Pulled By: abhimadan

fbshipit-source-id: 9e4e4fbdc5b0da161c89582566d184101ba8eb68
2018-10-30 15:34:27 -07:00
Yi Wu
f560c8f5c8 s/CacheAllocator/MemoryAllocator/g (#4590)
Summary:
Rename the interface, as it is mean to be a generic interface for memory allocation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4590

Differential Revision: D10866340

Pulled By: yiwu-arbug

fbshipit-source-id: 85cb753351a40cb856c046aeaa3f3b369eef3d16
2018-10-26 14:30:30 -07:00
Abhishek Madan
7528130e38 Cache fragmented range tombstones in BlockBasedTableReader (#4493)
Summary:
This allows tombstone fragmenting to only be performed when the table is opened, and cached for subsequent accesses.

On the same DB used in #4449, running `readrandom` results in the following:
```
readrandom   :       0.983 micros/op 1017076 ops/sec;   78.3 MB/s (63103 of 100000 found)
```

Now that Get performance in the presence of range tombstones is reasonable, I also compared the performance between a DB with range tombstones, "expanded" range tombstones (several point tombstones that cover the same keys the equivalent range tombstone would cover, a common workaround for DeleteRange), and no range tombstones. The created DBs had 5 million keys each, and DeleteRange was called at regular intervals (depending on the total number of range tombstones being written) after 4.5 million Puts. The table below summarizes the results of a `readwhilewriting` benchmark (in order to provide somewhat more realistic results):
```
   Tombstones?    | avg micros/op | stddev micros/op |  avg ops/s   | stddev ops/s
----------------- | ------------- | ---------------- | ------------ | ------------
None              |        0.6186 |          0.04637 | 1,625,252.90 | 124,679.41
500 Expanded      |        0.6019 |          0.03628 | 1,666,670.40 | 101,142.65
500 Unexpanded    |        0.6435 |          0.03994 | 1,559,979.40 | 104,090.52
1k Expanded       |        0.6034 |          0.04349 | 1,665,128.10 | 125,144.57
1k Unexpanded     |        0.6261 |          0.03093 | 1,600,457.50 |  79,024.94
5k Expanded       |        0.6163 |          0.05926 | 1,636,668.80 | 154,888.85
5k Unexpanded     |        0.6402 |          0.04002 | 1,567,804.70 | 100,965.55
10k Expanded      |        0.6036 |          0.05105 | 1,667,237.70 | 142,830.36
10k Unexpanded    |        0.6128 |          0.02598 | 1,634,633.40 |  72,161.82
25k Expanded      |        0.6198 |          0.04542 | 1,620,980.50 | 116,662.93
25k Unexpanded    |        0.5478 |          0.0362  | 1,833,059.10 | 121,233.81
50k Expanded      |        0.5104 |          0.04347 | 1,973,107.90 | 184,073.49
50k Unexpanded    |        0.4528 |          0.03387 | 2,219,034.50 | 170,984.32
```

After a large enough quantity of range tombstones are written, range tombstone Gets can become faster than reading from an equivalent DB with several point tombstones.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4493

Differential Revision: D10842844

Pulled By: abhimadan

fbshipit-source-id: a7d44534f8120e6aabb65779d26c6b9df954c509
2018-10-25 19:26:44 -07:00
Abhishek Madan
8c78348c77 Use only "local" range tombstones during Get (#4449)
Summary:
Previously, range tombstones were accumulated from every level, which
was necessary if a range tombstone in a higher level covered a key in a lower
level. However, RangeDelAggregator::AddTombstones's complexity is based on
the number of tombstones that are currently stored in it, which is wasteful in
the Get case, where we only need to know the highest sequence number of range
tombstones that cover the key from higher levels, and compute the highest covering
sequence number at the current level. This change introduces this optimization, and
removes the use of RangeDelAggregator from the Get path.

In the benchmark results, the following command was used to initialize the database:
```
./db_bench -db=/dev/shm/5k-rts -use_existing_db=false -benchmarks=filluniquerandom -write_buffer_size=1048576 -compression_type=lz4 -target_file_size_base=1048576 -max_bytes_for_level_base=4194304 -value_size=112 -key_size=16 -block_size=4096 -level_compaction_dynamic_level_bytes=true -num=5000000 -max_background_jobs=12 -benchmark_write_rate_limit=20971520 -range_tombstone_width=100 -writes_per_range_tombstone=100 -max_num_range_tombstones=50000 -bloom_bits=8
```

...and the following command was used to measure read throughput:
```
./db_bench -db=/dev/shm/5k-rts/ -use_existing_db=true -benchmarks=readrandom -disable_auto_compactions=true -num=5000000 -reads=100000 -threads=32
```

The filluniquerandom command was only run once, and the resulting database was used
to measure read performance before and after the PR. Both binaries were compiled with
`DEBUG_LEVEL=0`.

Readrandom results before PR:
```
readrandom   :       4.544 micros/op 220090 ops/sec;   16.9 MB/s (63103 of 100000 found)
```

Readrandom results after PR:
```
readrandom   :      11.147 micros/op 89707 ops/sec;    6.9 MB/s (63103 of 100000 found)
```

So it's actually slower right now, but this PR paves the way for future optimizations (see #4493).

----
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4449

Differential Revision: D10370575

Pulled By: abhimadan

fbshipit-source-id: 9a2e152be1ef36969055c0e9eb4beb0d96c11f4d
2018-10-24 12:31:12 -07:00
Zhongyi Xie
21bf7421ca use per-level perf context for bloom filter related counters (#4581)
Summary:
PR https://github.com/facebook/rocksdb/pull/4226 introduced per-level perf context which allows breaking down perf context by levels.
This PR takes advantage of the feature to populate a few counters related to bloom filters
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4581

Differential Revision: D10518010

Pulled By: miasantreble

fbshipit-source-id: 011244561783ec860d32d5b0fa6bce6e78d70ef8
2018-10-24 12:21:38 -07:00
Neil Mayhew
43dbd4411e Adapt three unit tests with newer compiler/libraries (#4562)
Summary:
This fixes three tests that fail with relatively recent tools and libraries:

The tests are:

* `spatial_db_test`
* `table_test`
* `db_universal_compaction_test`

I'm using:

* `gcc` 7.3.0
* `glibc` 2.27
* `snappy` 1.1.7
* `gflags` 2.2.1
* `zlib` 1.2.11
* `bzip2` 1.0.6.0.1
* `lz4` 1.8.2
* `jemalloc` 5.0.1

The versions used in the Travis environment (which is two Ubuntu LTS versions behind the current one and doesn't use `lz4` or `jemalloc`) don't seem to have a problem. However, to be safe, I verified that these tests pass with and without my changes in a trusty Docker container without `lz4` and `jemalloc`.

However, I do get an unrelated set of other failures when using a trusty Docker container that uses `lz4` and `jemalloc`:

```
db/db_universal_compaction_test.cc:506: Failure
Value of: num + 1
  Actual: 3
Expected: NumSortedRuns(1)
Which is: 4
[  FAILED  ] UniversalCompactionNumLevels/DBTestUniversalCompaction.DynamicUniversalCompactionReadAmplification/0, where GetParam() = (1, false) (1189 ms)
[ RUN      ] UniversalCompactionNumLevels/DBTestUniversalCompaction.DynamicUniversalCompactionReadAmplification/1
db/db_universal_compaction_test.cc:506: Failure
Value of: num + 1
  Actual: 3
Expected: NumSortedRuns(1)
Which is: 4
[  FAILED  ] UniversalCompactionNumLevels/DBTestUniversalCompaction.DynamicUniversalCompactionReadAmplification/1, where GetParam() = (1, true) (1246 ms)
[ RUN      ] UniversalCompactionNumLevels/DBTestUniversalCompaction.DynamicUniversalCompactionReadAmplification/2
db/db_universal_compaction_test.cc:506: Failure
Value of: num + 1
  Actual: 3
Expected: NumSortedRuns(1)
Which is: 4
[  FAILED  ] UniversalCompactionNumLevels/DBTestUniversalCompaction.DynamicUniversalCompactionReadAmplification/2, where GetParam() = (3, false) (1237 ms)
[ RUN      ] UniversalCompactionNumLevels/DBTestUniversalCompaction.DynamicUniversalCompactionReadAmplification/3
db/db_universal_compaction_test.cc:506: Failure
Value of: num + 1
  Actual: 3
Expected: NumSortedRuns(1)
Which is: 4
[  FAILED  ] UniversalCompactionNumLevels/DBTestUniversalCompaction.DynamicUniversalCompactionReadAmplification/3, where GetParam() = (3, true) (1195 ms)
[ RUN      ] UniversalCompactionNumLevels/DBTestUniversalCompaction.DynamicUniversalCompactionReadAmplification/4
db/db_universal_compaction_test.cc:506: Failure
Value of: num + 1
  Actual: 3
Expected: NumSortedRuns(1)
Which is: 4
[  FAILED  ] UniversalCompactionNumLevels/DBTestUniversalCompaction.DynamicUniversalCompactionReadAmplification/4, where GetParam() = (5, false) (1161 ms)
[ RUN      ] UniversalCompactionNumLevels/DBTestUniversalCompaction.DynamicUniversalCompactionReadAmplification/5
db/db_universal_compaction_test.cc:506: Failure
Value of: num + 1
  Actual: 3
Expected: NumSortedRuns(1)
Which is: 4
[  FAILED  ] UniversalCompactionNumLevels/DBTestUniversalCompaction.DynamicUniversalCompactionReadAmplification/5, where GetParam() = (5, true) (1229 ms)
```

I haven't attempted to fix these since I'm not using trusty and Travis doesn't use `lz4` and `jemalloc`. However, the final commit in this PR does at least fix the compilation errors that occur when using trusty's version of `lz4`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4562

Differential Revision: D10510917

Pulled By: maysamyabandeh

fbshipit-source-id: 59534042015ec339270e5fc2f6ac4d859370d189
2018-10-24 08:17:56 -07:00
Zhongyi Xie
d6ec288703 Add PerfContextByLevel to provide per level perf context information (#4226)
Summary:
Current implementation of perf context is level agnostic. Making it hard to do performance evaluation for the LSM tree. This PR adds `PerfContextByLevel` to decompose the counters by level.
This will be helpful when analyzing point and range query performance as well as tuning bloom filter
Also replaced __thread with thread_local keyword for perf_context
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4226

Differential Revision: D10369509

Pulled By: miasantreble

fbshipit-source-id: f1ced4e0de5fcebdb7f9cff36164516bc6382d82
2018-10-17 11:19:40 -07:00
Yanqin Jin
729a617b5b Add listener to sample file io (#3933)
Summary:
We would like to collect file-system-level statistics including file name, offset, length, return code, latency, etc., which requires to add callbacks to intercept file IO function calls when RocksDB is running.
To collect file-system-level statistics, users can inherit the class `EventListener`, as in `TestFileOperationListener `. Note that `TestFileOperationListener::ShouldBeNotifiedOnFileIO()` returns true.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3933

Differential Revision: D10219571

Pulled By: riversand963

fbshipit-source-id: 7acc577a2d31097766a27adb6f78eaf8b1e8ff15
2018-10-12 18:36:11 -07:00
jsteemann
517d3b8b77 fix typo in error message, twice (#4457)
Summary:
Fixes a typo in error messages returned by Iterator::GetProperty(...)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4457

Differential Revision: D10281965

Pulled By: sagar0

fbshipit-source-id: 1cd3c665f467ef06cdfd9f482692e6f8568f3d22
2018-10-09 17:07:27 -07:00
Dmitry Alimov
e13d8dcbbb Fix typos in comments (#4456)
Summary:
Fix some typos in the comments
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4456

Differential Revision: D10209214

Pulled By: miasantreble

fbshipit-source-id: dff857ba60396bc95126e635db96d7dc8330d2cb
2018-10-04 20:46:50 -07:00
Zhongyi Xie
ce1fc5af09 fix unused param allocator in compression.h (#4453)
Summary:
this should fix currently failing contrun test: rocksdb-contrun-no_compression, rocksdb-contrun-tsan, rocksdb-contrun-tsan_crash
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4453

Differential Revision: D10202626

Pulled By: miasantreble

fbshipit-source-id: 850b07f14f671b5998c22d8239e2a55b2fc1e355
2018-10-04 13:24:22 -07:00
Igor Canadi
1cf5deb8fd Introduce CacheAllocator, a custom allocator for cache blocks (#4437)
Summary:
This is a conceptually simple change, but it touches many files to
pass the allocator through function calls.

We introduce CacheAllocator, which can be used by clients to configure
custom allocator for cache blocks. Our motivation is to hook this up
with folly's `JemallocNodumpAllocator`
(f43ce6d686/folly/experimental/JemallocNodumpAllocator.h),
but there are many other possible use cases.

Additionally, this commit cleans up memory allocation in
`util/compression.h`, making sure that all allocations are wrapped in a
unique_ptr as soon as possible.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4437

Differential Revision: D10132814

Pulled By: yiwu-arbug

fbshipit-source-id: be1343a4b69f6048df127939fea9bbc96969f564
2018-10-02 17:24:58 -07:00
Maysam Yabandeh
65ac72edd9 Fix bug in partition filters with format_version=4 (#4381)
Summary:
Value delta encoding in format_version 4 requires the differences between the size of two consecutive handles to be sent to BlockBuilder::Add. This applies not only to indexes on blocks but also the indexes on indexes and filters in partitioned indexes and filters respectively. The patch fixes a bug where the partitioned filters would encode the entire size of the handle rather than the difference of the size with the last size.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4381

Differential Revision: D9879505

Pulled By: maysamyabandeh

fbshipit-source-id: 27a22e49b482b927fbd5629dc310c46d63d4b6d1
2018-09-17 17:28:15 -07:00
Sagar Vemuri
ac46790374 Fix sync-point comment in Block destructor (#4380)
Summary:
This is a follow up to #4370. The earlier comment is not correct.

Thanks to ajkr for pointing this out.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4380

Differential Revision: D9874667

Pulled By: sagar0

fbshipit-source-id: f4e092d86b29c715258210b770643d367e38caae
2018-09-17 11:58:11 -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
Maysam Yabandeh
9ea9007b50 Reduce IndexBlockIter size (#4358)
Summary:
With #3983 the size of IndexBlockIter was increased. This had resulted in a regression on P50 latencies in one of our benchmarks. The patch reduces IndexBlockIter size be eliminating active_comparator_ field from the class.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4358

Differential Revision: D9781737

Pulled By: maysamyabandeh

fbshipit-source-id: 71e2b28d90ff0813db9e04b737ae73e185583c52
2018-09-12 10:03:35 -07:00
Andrew Kryczka
2c14662213 Revert "Digest ZSTD compression dictionary once per SST file (#4251)" (#4347)
Summary:
Reverting is needed to unblock a user building against master, who is blocked for multiple days due to a thread-safety issue in `GetEmptyDict`. We haven't been able to fix it quickly, so reverting.

Simply ran `git revert 6c40806e51a89386d2b066fddf73d3fd03a36f65`. There were no merge conflicts.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4347

Differential Revision: D9668365

Pulled By: ajkr

fbshipit-source-id: 0c56334f0a23cf5ee0233d4e4679eae6709739cd
2018-09-06 09:58:34 -07:00
cngzhnp
64324e329e Support pragma once in all header files and cleanup some warnings (#4339)
Summary:
As you know, almost all compilers support "pragma once" keyword instead of using include guards. To be keep consistency between header files, all header files are edited.

Besides this, try to fix some warnings about loss of data.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4339

Differential Revision: D9654990

Pulled By: ajkr

fbshipit-source-id: c2cf3d2d03a599847684bed81378c401920ca848
2018-09-05 18:13:31 -07:00
Andrew Kryczka
6c40806e51 Digest ZSTD compression dictionary once per SST file (#4251)
Summary:
In RocksDB, for a given SST file, all data blocks are compressed with the same dictionary. When we compress a block using the dictionary's raw bytes, the compression library first has to digest the dictionary to get it into a usable form. This digestion work is redundant and ideally should be done once per file.

ZSTD offers APIs for the caller to create and reuse a digested dictionary object (`ZSTD_CDict`). In this PR, we call `ZSTD_createCDict` once per file to digest the raw bytes. Then we use `ZSTD_compress_usingCDict` to compress each data block using the pre-digested dictionary. Once the file's created `ZSTD_freeCDict` releases the resources held by the digested dictionary.

There are a couple other changes included in this PR:

- Changed the parameter object for (un)compression functions from `CompressionContext`/`UncompressionContext` to `CompressionInfo`/`UncompressionInfo`. This avoids the previous pattern, where `CompressionContext`/`UncompressionContext` had to be mutated before calling a (un)compression function depending on whether dictionary should be used. I felt that mutation was error-prone so eliminated it.
- Added support for digested uncompression dictionaries (`ZSTD_DDict`) as well. However, this PR does not support reusing them across uncompression calls for the same file. That work is deferred to a later PR when we will store the `ZSTD_DDict` objects in block cache.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4251

Differential Revision: D9257078

Pulled By: ajkr

fbshipit-source-id: 21b8cb6bbdd48e459f1c62343780ab66c0a64438
2018-08-23 19:28:18 -07:00
Fenggang Wu
da40d45267 DataBlockHashIndex: avoiding expensive iiter->Next when handling hash kNoEntry (#4296)
Summary:
When returning `kNoEntry` from HashIndex lookup, previously we invalidate the
`biter` by set `current_=restarts_`, so that the search can continue to the next
block in case the search result may reside in the next block.

There is one problem: when we are searching for a missing key, if the search
finds a `kNoEntry` and continue the search to the next block, there is also a
non-trivial possibility that the HashIndex return `kNoEntry` too, and the
expensive index iterator `Next()` will happen several times for nothing.

The solution is that if the hash table returns `kNoEntry`, `SeekForGetImpl()` just search the last restart interval for the key. It will stop at the first key that is large than the seek_key, or to the end of the block, and each case will be handled correctly.

Microbenchmark script:
```
TEST_TMPDIR=/dev/shm ./db_bench --benchmarks=fillseq,readtocache,readmissing \
          --cache_size=20000000000  --use_data_block_hash_index={true|false}
```

`readmissing` performance (lower is better):
```
binary:                      3.6098 micros/op
hash (before applying diff): 4.1048 micros/op
hash (after  applying diff): 3.3502 micros/op
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4296

Differential Revision: D9419159

Pulled By: fgwu

fbshipit-source-id: 21e3eedcccbc47a249aa8eb4bf405c9def0b8a05
2018-08-23 10:12:58 -07:00
Yanqin Jin
bb5dcea98e Add path to WritableFileWriter. (#4039)
Summary:
We want to sample the file I/O issued by RocksDB and report the function calls. This requires us to include the file paths otherwise it's hard to tell what has been going on.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4039

Differential Revision: D8670178

Pulled By: riversand963

fbshipit-source-id: 97ee806d1c583a2983e28e213ee764dc6ac28f7a
2018-08-23 10:12:58 -07:00
Fenggang Wu
640cfa7c33 DataBlockHashIndex: fix comment in NumRestarts() (#4286)
Summary:
Improve the description of the backward compatibility check in NumRestarts()
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4286

Differential Revision: D9412490

Pulled By: fgwu

fbshipit-source-id: ea7dd5c61d8ff8eacef623b729d4e4fd53cca066
2018-08-21 17:12:45 -07:00
Fenggang Wu
6d37fdb365 DataBlockHashIndex: Remove the division from EstimateSize() (#4293)
Summary:
`BlockBasedTableBuilder::Add()` eventually calls
`DataBlockHashIndexBuilder::EstimateSize()`. The previous implementation
divides the `num_keys` by the `util_ratio_` to get an estimizted `num_buckets`.
Such division is expensive as it happens in every
`BlockBasedTableBuilder::Add()`.

This diff estimates the `num_buckets` by double addition instead of double
division. Specifically, in each `Add()`, we add `bucket_per_key_`
(inverse of `util_ratio_`) to the current `estimiated_num_buckets_`. The cost is
that we are gonna have the `estimated_num_buckets_` stored as one extra field
in the DataBlockHashIndexBuilder.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4293

Differential Revision: D9412472

Pulled By: fgwu

fbshipit-source-id: 2925c8509a401e7bd3c1ab1d9e9c7244755c277a
2018-08-20 23:13:50 -07:00
Siying Dong
dc064f302e Suppress two CLANG Analyze warning (#4291)
Summary:
Suppress two CLANG analyze warnings. They don't seem to be real bugs
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4291

Differential Revision: D9407333

Pulled By: siying

fbshipit-source-id: 2ed63d88fa0b217fdccb1572d7508467c2203dc8
2018-08-20 16:57:38 -07:00
Andrey Zagrebin
fa4de6e30f #3865 followup for fix performance degression introduced by switching order of operands (#4284)
Summary:
Followup for #4266. There is one more place in **get_context.cc** where **MergeOperator::ShouldMerge** should be called with reversed list of operands.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4284

Differential Revision: D9380008

Pulled By: sagar0

fbshipit-source-id: 70ec26e607e5b88465e1acbdcd6c6171bd76b9f2
2018-08-17 10:57:25 -07:00
Fenggang Wu
9d646a6311 Add db_bench options of data block hash index (#4281)
Summary:
Add `--data_block_index_type` and `--data_block_hash_table_util_ratio` option to `db_bench`.

`--data_block_index_type` can be either of `binary` (default) or `binary_and_hash`;
`--data_block_hash_table_util_ratio` will be a double. The default value is `0.75`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4281

Differential Revision: D9361476

Pulled By: fgwu

fbshipit-source-id: dc53e01acef9db81b9eec5e8a96f3bc8ed718c10
2018-08-16 18:42:46 -07:00
Fenggang Wu
19ec44fd39 Improve point-lookup performance using a data block hash index (#4174)
Summary:
Add hash index support to data blocks, which helps to reduce the CPU utilization of point-lookup operations. This feature is backward compatible with the data block created without the hash index. It is disabled by default unless `BlockBasedTableOptions::data_block_index_type` is set to `data_block_index_type = kDataBlockBinaryAndHash.`

The DB size would be bigger with the hash index option as a hash table is added at the end of each data block. If the hash utilization ratio is 1:1, the space overhead is one byte per key. The hash table utilization ratio is adjustable using `BlockBasedTableOptions::data_block_hash_table_util_ratio`. A lower utilization ratio will improve more on the point-lookup efficiency, but take more space too.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4174

Differential Revision: D8965914

Pulled By: fgwu

fbshipit-source-id: 1c6bae5d1fc39c80282d8890a72e9e67bc247198
2018-08-15 14:30:03 -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
Maysam Yabandeh
d511f35ea7 Fix wrong partitioned index size recorded in properties block (#4259)
Summary:
After refactoring in https://github.com/facebook/rocksdb/pull/4158 the properties block is written after the index block. This breaks the existing logic in estimating the index size in partitioned indexes. The patch fixes that by using the accurate index block size, which is available since by the time we write the properties block, the index block is already written.
The patch also fixes an issue in estimating the partition size with format_version=3 which was resulting into partitions smaller than the configured metadata_block_size.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4259

Differential Revision: D9274454

Pulled By: maysamyabandeh

fbshipit-source-id: c82d045505cca3e7ed1a44ee1eaa26e4f25a4272
2018-08-10 15:27:20 -07:00
Maysam Yabandeh
058026a885 Fix unity compile error (#4257)
Summary:
Fix the compile error in "make unity_test" caused by #3983.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4257

Differential Revision: D9271740

Pulled By: maysamyabandeh

fbshipit-source-id: 94e56d1675bf8bdc0e94439467eb4f40dd107517
2018-08-10 10:27:55 -07:00
Maysam Yabandeh
caf0f53a74 Index value delta encoding (#3983)
Summary:
Given that index value is a BlockHandle, which is basically an <offset, size> pair we can apply delta encoding on the values. The first value at each index restart interval encoded the full BlockHandle but the rest encode only the size. Refer to IndexBlockIter::DecodeCurrentValue for the detail of the encoding. This reduces the index size which helps using the  block cache more efficiently. The feature is enabled with using format_version 4.

The feature comes with a bit of cpu overhead which should be paid back by the higher cache hits due to smaller index block size.
Results with sysbench read-only using 4k blocks and using 16 index restart interval:
Format 2:
19585   rocksdb read-only range=100
Format 3:
19569   rocksdb read-only range=100
Format 4:
19352   rocksdb read-only range=100
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3983

Differential Revision: D8361343

Pulled By: maysamyabandeh

fbshipit-source-id: f882ee082322acac32b0072e2bdbb0b5f854e651
2018-08-09 16:58:40 -07:00
Maysam Yabandeh
eb8885a08a Return correct usable_size for BlockContents (#4246)
Summary:
If jemalloc is disabled or the API is incorrectly referenced (jemalloc api on windows have a prefix je_) memory usage is incorrectly reported for all block sizes. This is because sizeof(char) is always 1. sizeof() is calculated at compile time and *(char*) is char. The patch uses the size of the slice to fix that.
Fixes #4245
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4246

Differential Revision: D9233958

Pulled By: maysamyabandeh

fbshipit-source-id: 9646933b24504e2814c7379f06a31148829c6b4e
2018-08-08 17:43:00 -07:00
Yanqin Jin
54de56844d Remove random writes from SST file ingestion (#4172)
Summary:
RocksDB used to store global_seqno in external SST files written by
SstFileWriter. During file ingestion, RocksDB uses `pwrite` to update the
`global_seqno`. Since random write is not supported in some non-POSIX compliant
file systems, external SST file ingestion is not supported on these file
systems. To address this limitation, we no longer update `global_seqno` during
file ingestion. Later RocksDB uses the MANIFEST and other information in table
properties to deduce global seqno for externally-ingested SST files.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4172

Differential Revision: D8961465

Pulled By: riversand963

fbshipit-source-id: 4382ec85270a96be5bc0cf33758ca2b167b05071
2018-07-27 16:12:23 -07:00
Fenggang Wu
a11df583ec Add DataBlockIndexType option in BlockBasedTableOptions (#4150)
Summary:
Added DataBlockIndexType option in BlockBasedTableOptions.
```
enum DataBlockIndexType : char {
    kDataBlockBinarySearch = 0, // traditional block type
    kDataBlockHashIndex = 1, // additional hash index appended to the end.
};
```
The default type is the traditional binary seek option: `kDataBlockBinarySearch`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4150

Differential Revision: D8895958

Pulled By: fgwu

fbshipit-source-id: 480adef48104cf11d30db3bad9a73f98b4a80c10
2018-07-27 15:42:27 -07:00
Siying Dong
2a81633da2 Fix bug when seeking backward against an out-of-bound iterator (#4187)
Summary:
92ee3350e0 introduces an out-of-bound check in BlockBasedTableIterator::Valid(). However, this flag is not reset when re-seeking in backward direction. This caused the iterator to be invalide by mistake. Fix it by always resetting the out-of-bound flag in every seek.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4187

Differential Revision: D8996600

Pulled By: siying

fbshipit-source-id: b6235ea614f71381e50e7904c4fb036300604ac1
2018-07-25 17:14:01 -07:00
Fenggang Wu
8805ec2f49 DataBlockHashIndex: Standalone Implementation with Unit Test (#4139)
Summary:
The first step of the `DataBlockHashIndex` implementation. A string based hash table is implemented and unit-tested.

`DataBlockHashIndexBuilder`: `Add()` takes pairs of `<key, restart_index>`, and formats it into a string when `Finish()` is called.
`DataBlockHashIndex`: initialized by the formatted string, and can interpret it as a hash table. Lookup for a key is supported by iterator operation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4139

Reviewed By: sagar0

Differential Revision: D8866764

Pulled By: fgwu

fbshipit-source-id: 7f015f0098632c65979a22898a50424384730b10
2018-07-24 11:43:37 -07:00
Zhongyi Xie
f95a5b2464 Avoid unnecessary big for-loop when reporting ticker stats stored in GetContext (#3490)
Summary:
Currently in `Version::Get` when reporting ticker stats stored in `GetContext`, there is a big for-loop through all `Ticker` which adds unnecessary cost to overall CPU usage. We can optimize by storing only ticker values that are used in `Get()` calls in a new struct `GetContextStats` since only a small fraction of all tickers are used in `Get()` calls. For comparison, with the new approach we only need to visit 17 values while old approach will require visiting 100+ `Ticker`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3490

Differential Revision: D6969154

Pulled By: miasantreble

fbshipit-source-id: fc27072965a3a94125a3e6883d20dafcf5b84029
2018-07-20 16:58:13 -07:00
Siying Dong
a5e851e113 Reformatting some recent changes (#4161)
Summary:
Lint is not happy with some new code recently committed. Format them.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4161

Differential Revision: D8940582

Pulled By: siying

fbshipit-source-id: c9b43b1ef8c88b5e923911058b44eb77234b36b7
2018-07-20 14:43:38 -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
Andrew Kryczka
ab35505e21 Write properties metablock last in block-based tables (#4158)
Summary:
The properties meta-block should come at the end since we always need to
read it when opening a file, unlike index/filter/other meta-blocks, which
are sometimes read depending on the user's configuration. This ordering
will allow us to (in a future PR) do a small readahead on the end of the file
to read properties and meta-index blocks with one I/O.

The bulk of this PR is a refactoring of the `BlockBasedTableBuilder::Finish`
function. It was previously too large with inconsistent error handling, which
made it difficult to change. So I broke it up into one function per meta-block
write, and tried to make error handling consistent within those functions.
Then reordering the metablocks was trivial -- just reorder the calls to these
helper functions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4158

Differential Revision: D8921705

Pulled By: ajkr

fbshipit-source-id: 96c9cc3182eb1adf11af46adab79dbeba7b12fcc
2018-07-20 09:11:59 -07:00
Andrew Kryczka
b5613227a9 Smaller tail readahead when not reading index/filters (#4159)
Summary:
In all cases during `BlockBasedTable::Open`, we issue at least three read requests to the file's tail: (1) footer, (2) metaindex block, and (3) properties block. Depending on the config, we may also read other metablocks like filter and index.

This PR issues smaller readahead when we expect to do only the three necessary reads mentioned above. Then, 4KB should be enough (ignoring the case where there are lots of user-defined properties). We can keep doing 512KB readahead when additional reads are expected.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4159

Differential Revision: D8924002

Pulled By: ajkr

fbshipit-source-id: cfc713275de4d05ce11f18571f1d72e27ccd3356
2018-07-19 16:13:22 -07:00
Maysam Yabandeh
b55da012f6 Refactor IndexBlockIter (#4141)
Summary:
Refactor IndexBlockIter to reduce conditional branches on key_includes_seq_. IndexBlockIter::Prev is also separated from DataBlockIter::Prev, not to cache the prev entries as they are of less importance when iterating over the index block.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4141

Differential Revision: D8866437

Pulled By: maysamyabandeh

fbshipit-source-id: fdac76880426fc2be7d3c6354c09ab98f6657d4b
2018-07-16 17:13:10 -07:00
Siying Dong
8f06b4fa01 Separate some IndexBlockIter logic from BlockIter (#4136)
Summary:
Some logic only related to IndexBlockIter is separated from BlockIter to IndexBlockIter. This is done by writing an exclusive Seek() and SeekForPrev() for DataBlockIter, and all metadata block iter and tombstone block iter now use data block iter. Dealing with the BinarySeek() sharing problem by passing in the comparator to use.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4136

Reviewed By: maysamyabandeh

Differential Revision: D8859673

Pulled By: siying

fbshipit-source-id: 703e5e6824b82b7cbf4721f3594b94127797ca9e
2018-07-16 10:13:18 -07:00
Nathan VanBenschoten
ef7815b803 Support range deletion tombstones in IngestExternalFile SSTs (#3778)
Summary:
Fixes #3391.

This change adds a `DeleteRange` method to `SstFileWriter` and adds
support for ingesting SSTs with range deletion tombstones. This is
important for applications that need to atomically ingest SSTs while
clearing out any existing keys in a given key range.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3778

Differential Revision: D8821836

Pulled By: anand1976

fbshipit-source-id: ca7786c1947ff129afa703dab011d524c7883844
2018-07-13 22:43:09 -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
Tamir Duberstein
7bee48bdbd Add GCC 8 to Travis (#3433)
Summary:
- Avoid `strdup` to use jemalloc on Windows
- Use `size_t` for consistency
- Add GCC 8 to Travis
- Add CMAKE_BUILD_TYPE=Release to Travis
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3433

Differential Revision: D6837948

Pulled By: sagar0

fbshipit-source-id: b8543c3a4da9cd07ee9a33f9f4623188e233261f
2018-07-13 10:58:06 -07:00
Maysam Yabandeh
d4ad32d7bd Refactor BlockIter (#4121)
Summary:
BlockIter is getting crowded including details that specific only to either index or data blocks. The patch moves down such details to DataBlockIter and IndexBlockIter, both inheriting from BlockIter.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4121

Differential Revision: D8816832

Pulled By: maysamyabandeh

fbshipit-source-id: d492e74155c11d8a0c1c85cd7ee33d24c7456197
2018-07-12 17:27:31 -07:00
Nikhil Benesch
5cd8240b86 Test range deletions with more configurations (#4021)
Summary:
Run the basic range deletion tests against the standard set of
configurations. This testing exposed that files with hash indexes and
partitioned indexes were not handling the case where the file contained
only range deletions--i.e., where the index was empty.

Additionally file a TODO about the fact that range deletions are broken
when allow_mmap_reads = true is set.

/cc ajkr nvanbenschoten

Best viewed with ?w=1: https://github.com/facebook/rocksdb/pull/4021/files?w=1
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4021

Differential Revision: D8811860

Pulled By: ajkr

fbshipit-source-id: 3cc07e6d6210a2a00b932866481b3d5c59775343
2018-07-11 15:57:49 -07:00
Yanqin Jin
d4d9fe8e57 Fix a bug caused by not copying the block trailer. (#4096)
Summary:
This was caught by crash test, and the following is a simple way to reproduce it and verify the fix.
One way to trigger this code path is to use the following configuration:
- Compress SST file
- Enable direct IO and prefetch buffer
- Do NOT use compressed block cache
Closes https://github.com/facebook/rocksdb/pull/4096

Differential Revision: D8742009

Pulled By: riversand963

fbshipit-source-id: f13381078bbb0dce92f60bd313a78ab602bcacd2
2018-07-06 13:12:39 -07:00
Yanqin Jin
39218a72a4 Increase the size of LRU cache. (#4090)
Summary:
Increase the size of each shard so that the number of cache hit/miss match
expectation. Otherwise FilterBlockInBlockCache test will fail.
Closes https://github.com/facebook/rocksdb/pull/4090

Differential Revision: D8736158

Pulled By: riversand963

fbshipit-source-id: 5cdbc06b02390389fd5b72a6d251d88949ad3d91
2018-07-05 11:45:11 -07:00
Maysam Yabandeh
2462763b2e Fix mis-spoken assert on prefetch_filter and prefetch_index (#4077)
Summary:
We can have prefetch_index without prefetch_filter but not the other way around. The assert statement is fixed.
Closes https://github.com/facebook/rocksdb/pull/4077

Differential Revision: D8694472

Pulled By: maysamyabandeh

fbshipit-source-id: ccd2804d9d9cdafb1c3e65062c7bc38603e69004
2018-06-29 09:28:12 -07:00
Maysam Yabandeh
29ffbb8a50 Charging block cache more accurately (#4073)
Summary:
Currently the block cache is charged only by the size of the raw data block and excludes the overhead of the c++ objects that contain the raw data block. The patch improves the accuracy of the charge by including the c++ object overhead into it.
Closes https://github.com/facebook/rocksdb/pull/4073

Differential Revision: D8686552

Pulled By: maysamyabandeh

fbshipit-source-id: 8472f7fc163c0644533bc6942e20cdd5725f520f
2018-06-29 08:57:20 -07:00
Zhongyi Xie
14f409c0f1 PrefixMayMatch: remove unnecessary check for prefix_extractor_ (#4067)
Summary:
with https://github.com/facebook/rocksdb/pull/3601 and https://github.com/facebook/rocksdb/pull/3899, `prefix_extractor_` is not really being used in block based filter and full filter's version of `PrefixMayMatch` because now `prefix_extractor` is passed as an argument. Also it is now possible that prefix_extractor_ may be initialized to nullptr when a non-standard prefix_extractor is used and also for ROCKSDB_LITE. Removing these checks should not break any existing tests.
Closes https://github.com/facebook/rocksdb/pull/4067

Differential Revision: D8669002

Pulled By: miasantreble

fbshipit-source-id: 0e701ba912b8a26734fadb72d15bb1b266b6176a
2018-06-27 20:42:43 -07:00
Zhichao Cao
1f6efabe23 Add bottommost_compression_opts to for bottommost_compression (#3985)
Summary:
…ression

 For `CompressionType` we have options `compression` and `bottommost_compression`. Thus, to make the compression options consitent with the compression type when bottommost_compression is enabled, we add the bottommost_compression_opts
Closes https://github.com/facebook/rocksdb/pull/3985

Reviewed By: riversand963

Differential Revision: D8385911

Pulled By: zhichao-cao

fbshipit-source-id: 07bc533dd61bcf1cef5927d8d62901c13d38d5fc
2018-06-27 17:42:38 -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