Commit Graph

1143 Commits

Author SHA1 Message Date
Andrew Kryczka 75d3b6fdf0 Redesign block cache pinning API (#7520)
Summary:
The old flag-based APIs (`BlockBasedTableOptions::pin_l0_filter_and_index_blocks_in_cache` and `BlockBasedTableOptions::pin_top_level_index_and_filter`) were insufficient for our needs. For example, it was impossible to pin only unpartitioned meta-blocks, which could prevent block cache contention when turning on dictionary compression or during a migration to partitioned indexes/filters. It was also impossible to pin all meta-blocks in memory while having predictable memory usage via block cache. If we had continued adding flags to address these scenarios, they would have had significant overlap causing confusion. Instead, this PR deprecates the flags and starts a new API with non-overlapping options.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7520

Test Plan:
- new unit test
- added new options to stress/crash test and ran for a while: `$ python tools/db_crashtest.py blackbox --simple --max_key=1000000 -write_buffer_size=1048576 -target_file_size_base=1048576 -max_bytes_for_level_base=4194304 --interval=10 -value_size_mult=33 -column_families=1 -reopen=0`

Reviewed By: pdillinger

Differential Revision: D24200034

Pulled By: ajkr

fbshipit-source-id: 3fa7cfc71e7960f7a867511dd6ae5834dd73b13e
2020-10-11 14:58:24 -07:00
Akanksha Mahajan 24498ab1ec Add few unit test cases in ASSERT_STATUS_CHECKED (#7500)
Summary:
Add status enforcement for following tests:
  1. import_column_family_test
  2. memory_test
  3. table_test

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7500

Reviewed By: zhichao-cao

Differential Revision: D24095887

Pulled By: akankshamahajan15

fbshipit-source-id: db8e1ec595852df143fad78a0c07bfdd27dc3c84
2020-10-08 11:22:44 -07:00
Akanksha Mahajan 38d0a365e3 Add Stats for MultiGet (#7366)
Summary:
Add following stats for MultiGet in Histogram to get more insight on MultiGet.
    1. Number of index and filter blocks read from file as part of MultiGet
    request per level.
    2. Number of data blocks read from file per level.
    3. Number of SST files loaded from file system per level.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7366

Reviewed By: anand1976

Differential Revision: D24127040

Pulled By: akankshamahajan15

fbshipit-source-id: e63a003056b833729b277edc0639c08fb432756b
2020-10-07 13:28:48 -07:00
sdong 2496d3d4b8 Avoid to suppress status code in ~BlockBasedTableBuilder (#7507)
Summary:
We just used a hacky way to fix db_basic_test: suppress status code in ~BlockBasedTableBuilder. Rather, we should pass them back in Finish() and suppress them in Abandon().

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7507

Test Plan: Watch existing tests to succeed.

Reviewed By: riversand963

Differential Revision: D24119527

fbshipit-source-id: 71c4d4a81c0fd1c5595224692275f20f7759973a
2020-10-05 14:58:49 -07:00
Levi Tamasi 5d16325ce3 Revert "Return error if Get() fails in Prefetching Filter blocks (#7463)" (#7505)
Summary:
This reverts commit 7d503e66a9.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7505

Reviewed By: ajkr

Differential Revision: D24100875

Pulled By: ltamasi

fbshipit-source-id: 8705e3e6e8be4b4fd175ffdb031baa6530b61151
2020-10-03 18:38:04 -07:00
Yanqin Jin 758ead5df7 Enforce status check for corruption_test (#7453)
Summary:
Enforce status check for corruption_test.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7453

Test Plan:
```
ASSERT_STATUS_CHECKED=1 make corruption_test
./corruption_test
```

Reviewed By: jay-zhuang

Differential Revision: D24006862

Pulled By: riversand963

fbshipit-source-id: 664677caf4c3007a25cf565cec3d677f2dcea130
2020-10-02 22:11:00 -07:00
Akanksha Mahajan 7d503e66a9 Return error if Get() fails in Prefetching Filter blocks (#7463)
Summary:
Right now all I/O failures under
PartitionFilterBlock::CacheDependencies() is swallowed. Return error in
case prefetch fails.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7463

Test Plan: make check -j64

Reviewed By: anand1976

Differential Revision: D24008226

Pulled By: akankshamahajan15

fbshipit-source-id: b65d63b2d01465db92500b78de7ad58650ec9b3b
2020-10-02 19:40:43 -07:00
darionyaphet f5e22ce607 fix dummy collector's name (#7442)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/7442

Reviewed By: jay-zhuang

Differential Revision: D24011201

Pulled By: ajkr

fbshipit-source-id: 54f24c29875f7575612a780f15a42cda918d6641
2020-10-01 15:22:47 -07:00
sdong 7508175558 Introduce options.check_flush_compaction_key_order (#7467)
Summary:
Introduce an new option options.check_flush_compaction_key_order, by default set to true, which checks key order of flush and compaction, and fail the operation if the order is violated.
Also did minor refactor hash checking code, which consolidates the hashing logic to a vlidation class, where the key ordering logic is added.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7467

Test Plan: Add unit tests to validate the check can catch reordering in flush and compaction, and can be properly disabled.

Reviewed By: riversand963

Differential Revision: D24010683

fbshipit-source-id: 8dd6292d2cda8006054e9ded7cfa4bf405f0527c
2020-10-01 10:10:26 -07:00
darionyaphet 2af46f1011 Move break into block (#7468)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/7468

Reviewed By: riversand963

Differential Revision: D24028736

Pulled By: ajkr

fbshipit-source-id: bd2b4b8d069491a16373d3d2705fddf7ebfe6723
2020-09-30 20:24:23 -07:00
Ramkumar Vadivelu e04a50923d Change ParseInternalKey() to return Status instead of bool (#7457)
Summary:
Fixes https://github.com/facebook/rocksdb/issues/7430

Change ParseInternalKey() to return Status instead of bool.

db_bench (seekrandom) based before/after results with value size of 100 bytes and 16 bytes can be found at (tests ran on an udb server):
https://www.dropbox.com/s/47bwamdy5ozngph/PIK_ret_Status_results.xlsx?dl=0

![db_bench_results](https://user-images.githubusercontent.com/62277872/94642825-2a21a800-029a-11eb-88f2-124136c83fd3.png)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7457

Reviewed By: ajkr

Differential Revision: D24002433

Pulled By: ramvadiv

fbshipit-source-id: ac253ecf577a29044c47c3fe254a01e71404c44c
2020-09-30 19:16:47 -07:00
Akanksha Mahajan 5997f6b17b Add Status check enforcement for unit tests (#7464)
Summary:
Add status check for unit tests : block_based_filter_block_test, block_fetcher_test, full_filter_block_test and partitioned_filter_block_test

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7464

Reviewed By: zhichao-cao

Differential Revision: D24011309

Pulled By: akankshamahajan15

fbshipit-source-id: d814803f94e8bb8b811ef170d20b22d52c1a3ff2
2020-09-30 12:48:05 -07:00
Jay Zhuang 1bdaef7a06 Status check enforcement for timestamp_basic_test (#7454)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/7454

Reviewed By: riversand963

Differential Revision: D23981719

Pulled By: jay-zhuang

fbshipit-source-id: 01073f73e54c17067b886c4a2f179b2804198399
2020-09-29 18:23:27 -07:00
anand76 bd5d9e2a1d Fix misspelling of PartitionedIndexIterator (#7450)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/7450

Reviewed By: zhichao-cao

Differential Revision: D23992811

Pulled By: anand1976

fbshipit-source-id: 71bd898aafce6a3add3c8cd86d9f0e0fb63860cf
2020-09-29 16:28:13 -07:00
sdong d08a9005b7 Make db_basic_test pass assert status checked (#7452)
Summary:
Add db_basic_test status check list. Some of the warnings are suppressed. It is possible that some of them are due to real bugs.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7452

Test Plan: See CI tests pass.

Reviewed By: zhichao-cao

Differential Revision: D23979764

fbshipit-source-id: 6151570c2a9b931b0fbb3fe939a94b2bd1583cbe
2020-09-29 09:49:04 -07:00
Andrew Kryczka 7a23a2175b enable Status check assertions for sst_file_reader_test (#7448)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/7448

Reviewed By: jay-zhuang

Differential Revision: D23973281

Pulled By: ajkr

fbshipit-source-id: 90fe55f1db904f1a236f3f7994d0806b8d24282c
2020-09-28 15:13:15 -07:00
Levi Tamasi 30fb9dd50f Introduce a helper method UncompressData (#7434)
Summary:
The patch introduces a helper method in `util/compression.h` called `UncompressData`
that dispatches calls to the correct uncompression method based on type, and changes
`UncompressBlockContentsForCompressionType` and `Benchmark::Uncompress` in
`db_bench` so they are implemented in terms of the new method. This eliminates
some code duplication. (`Benchmark::Compress` is also updated to use the previously
introduced `CompressData` helper.)

In addition, the patch brings the implementation of `Snappy_Uncompress` into sync with
the other uncompression methods by making the method compute the buffer size and allocate
the buffer itself. Finally, the patch eliminates some potentially risky back-and-forth conversions
between various unsigned and signed integer types by exposing the size of the allocated buffer
as a `size_t` instead of an `int`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7434

Test Plan:
`make check`
`./db_bench -benchmarks=compress,uncompress --compression_type ...`

Reviewed By: riversand963

Differential Revision: D23900011

Pulled By: ltamasi

fbshipit-source-id: b25df63ceec4639889be94acb22eb53e530c54e0
2020-09-25 09:01:45 -07:00
Andrew Kryczka 0698598f3a Fix scope of `ReadOptions` in `SstFileReader` (#7432)
Summary:
a4a4a2dabd changed the contract of `TableReader::NewIterator()` to require
`ReadOptions` outlive the returned iterator. But I didn't notice that
`SstFileReader` violates the new contract and needs to be adapted. The unit test
provided here exposes the problem when run under ASAN.

```
$ ./sst_file_reader_test --gtest_filter=SstFileReaderTest.ReadOptionsOutOfScope
Note: Google Test filter = SstFileReaderTest.ReadOptionsOutOfScope
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from SstFileReaderTest
[ RUN      ] SstFileReaderTest.ReadOptionsOutOfScope
=================================================================
==3238048==ERROR: AddressSanitizer: stack-use-after-scope on address 0x7ffd6189e158 at pc 0x000001298350 bp 0x7ffd6189c280 sp 0x7ffd6189c278
READ of size 8 at 0x7ffd6189e158 thread T0
    #0 0x129834f in rocksdb::BlockBasedTableIterator::InitDataBlock() table/block_based/block_based_table_iterator.cc:236
    https://github.com/facebook/rocksdb/issues/1 0x12b01f7 in rocksdb::BlockBasedTableIterator::SeekImpl(rocksdb::Slice const*) table/block_based/block_based_table_iterator.cc:77
    https://github.com/facebook/rocksdb/issues/2 0x844d28 in rocksdb::IteratorWrapperBase<rocksdb::Slice>::SeekToFirst() table/iterator_wrapper.h:116
    https://github.com/facebook/rocksdb/issues/3 0x844d28 in rocksdb::DBIter::SeekToFirst() db/db_iter.cc:1352
    https://github.com/facebook/rocksdb/issues/4 0x52482b in rocksdb::SstFileReaderTest_ReadOptionsOutOfScope_Test::TestBody() table/sst_file_reader_test.cc:150
    https://github.com/facebook/rocksdb/issues/5 0x5f433c in void testing::internal::HandleSehExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) third-party/gtest-1.8.1/fused-src/gtest/gtest-all.cc:3899
    https://github.com/facebook/rocksdb/issues/6 0x5f433c in void testing::internal::HandleExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) third-party/gtest-1.8.1/fused-src/gtest/gtest-all.cc:3935
    https://github.com/facebook/rocksdb/issues/7 0x5cc2de in testing::Test::Run() third-party/gtest-1.8.1/fused-src/gtest/gtest-all.cc:3973
    https://github.com/facebook/rocksdb/issues/8 0x5cc988 in testing::Test::Run() third-party/gtest-1.8.1/fused-src/gtest/gtest-all.cc:3965
    https://github.com/facebook/rocksdb/issues/9 0x5cc988 in testing::TestInfo::Run() third-party/gtest-1.8.1/fused-src/gtest/gtest-all.cc:4149
    https://github.com/facebook/rocksdb/issues/10 0x5cce9a in testing::TestInfo::Run() third-party/gtest-1.8.1/fused-src/gtest/gtest-all.cc:4124
    https://github.com/facebook/rocksdb/issues/11 0x5cce9a in testing::TestCase::Run() third-party/gtest-1.8.1/fused-src/gtest/gtest-all.cc:4267
    https://github.com/facebook/rocksdb/issues/12 0x5ce696 in testing::TestCase::Run() third-party/gtest-1.8.1/fused-src/gtest/gtest-all.cc:4253
    https://github.com/facebook/rocksdb/issues/13 0x5ce696 in testing::internal::UnitTestImpl::RunAllTests() third-party/gtest-1.8.1/fused-src/gtest/gtest-all.cc:6633
    https://github.com/facebook/rocksdb/issues/14 0x5f541c in bool testing::internal::HandleSehExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) third-party/gtest-1.8.1/fused-src/gtest/gtest-all.cc:3899
    https://github.com/facebook/rocksdb/issues/15 0x5f541c in bool testing::internal::HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) third-party/gtest-1.8.1/fused-src/gtest/gtest-all.cc:3935
    https://github.com/facebook/rocksdb/issues/16 0x5cee74 in testing::UnitTest::Run() third-party/gtest-1.8.1/fused-src/gtest/gtest-all.cc:6242
    https://github.com/facebook/rocksdb/issues/17 0x4c0332 in RUN_ALL_TESTS() third-party/gtest-1.8.1/fused-src/gtest/gtest.h:22104
    https://github.com/facebook/rocksdb/issues/18 0x4c0332 in main table/sst_file_reader_test.cc:213
    https://github.com/facebook/rocksdb/issues/19 0x7fb0263281a5 in __libc_start_main (/usr/local/fbcode/platform007/lib/libc.so.6+0x211a5)
    https://github.com/facebook/rocksdb/issues/20 0x523e56  (/data/users/andrewkr/rocksdb/sst_file_reader_test+0x523e56)

Address 0x7ffd6189e158 is located in stack of thread T0 at offset 568 in frame
    #0 0x52428f in rocksdb::SstFileReaderTest_ReadOptionsOutOfScope_Test::TestBody() table/sst_file_reader_test.cc:131

  This frame has 9 object(s):
    [32, 40) 'reader'
    [96, 104) '<unknown>'
    [160, 168) '<unknown>'
    [224, 232) 'iter'
    [288, 304) 'gtest_ar'
    [352, 368) '<unknown>'
    [416, 440) 'keys'
    [480, 512) '<unknown>'
    [544, 680) 'ropts' <== Memory access at offset 568 is inside this variable
HINT: this may be a false positive if your program uses some custom stack unwind mechanism or swapcontext
      (longjmp and C++ exceptions *are* supported)
 AddressSanitizer: stack-use-after-scope table/block_based/block_based_table_iterator.cc:236 in rocksdb::BlockBasedTableIterator::InitDataBlock()
...
```

The fix is to use `ArenaWrappedDBIter` which has support for holding a
`ReadOptions` in an `Arena` whose lifetime is tied to the iterator.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7432

Test Plan: verified the provided unit test no longer fails

Reviewed By: pdillinger

Differential Revision: D23880043

Pulled By: ajkr

fbshipit-source-id: 9464c37408f7bd7c9c4a90ceffb04d9f0ca7a494
2020-09-23 15:24:03 -07:00
yaphet 323a834d1d Fix typo (#7353)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/7353

Reviewed By: ajkr

Differential Revision: D23585525

Pulled By: zhichao-cao

fbshipit-source-id: 3f72d9663ec207b9dfe6b287d455a13d3c86879f
2020-09-19 18:11:16 -07:00
Peter Dillinger 93719fc953 Restore file size in backup table file names (and other cleanup) (#7400)
Summary:
Prior to 6.12, backup files using share_files_with_checksum had
the file size encoded in the file name, after the last '\_' and before
the last '.'. We considered this an implementation detail subject to
change, and indeed removed this information from the file name (with an
option to use old behavior) because it was considered
ineffective/inefficient for file name uniqueness. However, some
downstream RocksDB users were relying on this information since the file
size is not explicitly in the backup manifest file.

This primary purpose of this change is "retrofitting" the 6.12 release
(not yet a public release) to simultaneously support the benefits of the
new naming scheme (I/O performance and data correctness at scale) and
preserve the file size information, both as default behaviors. With this
change, we are essentially making the file size information encoded in
the file name an official, though obscure, extension of the backup meta
file format.

We preserve an option (kLegacyCrc32cAndFileSize) to use the original
"legacy" naming scheme, with its caveats, and make it easy to omit the
file size information (no kFlagIncludeFileSize), for more compact file
names. But note that changing the naming scheme used on an existing db
and backup directory can lead to transient space amplification, as some
files will be stored under two names in the shared_checksum directory.
Because some backups were saved using the original 6.12 naming scheme,
we offer two ways of dealing with those files: SST files generated by
older 6.12 versions can either use the default naming scheme in effect
when the SST files were generated (kFlagMatchInterimNaming, default, no
transient space amplification) or can use a new naming scheme (no
kFlagMatchInterimNaming, potential space amplification because some
already stored files getting a new name).

We don't have a natural way to detect which files were generated by
previous 6.12 versions, but this change hacks one in by changing DB
session ids to now use a more concise encoding, reducing file name
length, saving ~dozen bytes from SST files, and making them visually
distinct from DB ids so that they are less likely to be mixed up.

Two final auxiliary notes:
Recognizing that the backup file names have become a de facto part of
the backup meta schema, this change makes them easier to parse and
extend by putting a distinct marker, 's', before DB session ids embedded
in the name. When we extend this to allow custom checksums in the name,
they can get their own marker to ensure safe parsing. For backward
compatibility, file size does not get a marker but is assumed for
`_[0-9]+[.]`

Another change from initial 6.12 default behavior is never including
file custom checksum in the file name. Looking ahead to 6.13, we do not
want the default behavior to cause backup space amplification for
someone turning on file custom checksum checking in BackupEngine; we
want that to be an easy decision. When implemented, including file
custom checksums in backup file names will be a non-default option.

Actual file name patterns and priorities, as regexes:

    kLegacyCrc32cAndFileSize OR pre-6.12 SST file ->
      [0-9]+_[0-9]+_[0-9]+[.]sst
    kFlagMatchInterimNaming set (default) AND early 6.12 SST file ->
      [0-9]+_[0-9a-fA-F-]+[.]sst
    kUseDbSessionId AND NOT kFlagIncludeFileSize ->
      [0-9]+_s[0-9A-Z]{20}[.]sst
    kUseDbSessionId AND kFlagIncludeFileSize (default) ->
      [0-9]+_s[0-9A-Z]{20}_[0-9]+[.]sst

We might add opt-in options for more '\_' separated data in the name,
but embedded file size, if present, will always be after last '\_' and
before '.sst'.

This change was originally applied to version 6.12. (See https://github.com/facebook/rocksdb/issues/7390)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7400

Test Plan:
unit tests included. Sync point callbacks are used to mimic
previous version SST files.

Reviewed By: ajkr

Differential Revision: D23759587

Pulled By: pdillinger

fbshipit-source-id: f62d8af4e0978de0a34f26288cfbe66049b70025
2020-09-17 10:24:22 -07:00
mrambacher a08d6f18f0 Add more tests to ASSERT_STATUS_CHECKED (#7367)
Summary:
db_options_test
options_file_test
auto_roll_logger_test
options_util_test
persistent_cache_test

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7367

Reviewed By: jay-zhuang

Differential Revision: D23712520

Pulled By: zhichao-cao

fbshipit-source-id: 99b331e357f5d6a6aabee89d1bd933002cbb3908
2020-09-16 15:48:07 -07:00
mrambacher 7d472accdc Bring the Configurable options together (#5753)
Summary:
This PR merges the functionality of making the ColumnFamilyOptions, TableFactory, and DBOptions into Configurable into a single PR, resolving any merge conflicts

Pull Request resolved: https://github.com/facebook/rocksdb/pull/5753

Reviewed By: ajkr

Differential Revision: D23385030

Pulled By: zhichao-cao

fbshipit-source-id: 8b977a7731556230b9b8c5a081b98e49ee4f160a
2020-09-14 17:01:01 -07:00
Jay Zhuang 8a8a01c642 Fix compile error for old gcc-4.8 (#7358)
Summary:
gcc-4.8 returns error when using the constructor. Not sure if it's a compiler bug/limitation or code issue:
```
table/block_based/block_based_table_reader.cc:3183:67: error: use of deleted function ‘rocksdb::WritableFileStringStreamAdapter::WritableFileStringStreamAdapter(rocksdb::WritableFileStringStreamAdapter&&)’
```

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7358

Reviewed By: pdillinger

Differential Revision: D23577651

Pulled By: jay-zhuang

fbshipit-source-id: b0197e3d3538da61a6f3866410d88d2047fb9695
2020-09-08 12:09:34 -07:00
Akanksha Mahajan b175eceb09 Store FSWritableFilePtr object in WritableFileWriter (#7193)
Summary:
Replace FSWritableFile pointer with FSWritableFilePtr
    object in WritableFileWriter.
    This new object wraps FSWritableFile pointer.

    Objective: If tracing is enabled, FSWritableFile Ptr returns
    FSWritableFileTracingWrapper pointer that includes all necessary
    information in IORecord and calls underlying FileSystem and invokes
    IOTracer to dump that record in a binary file. If tracing is disabled
    then, underlying FileSystem pointer is returned directly.
    FSWritableFilePtr wrapper class is added to bypass the
    FSWritableFileWrapper when
    tracing is disabled.

    Test Plan: make check -j64

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7193

Reviewed By: anand1976

Differential Revision: D23355915

Pulled By: akankshamahajan15

fbshipit-source-id: e62a27a13c1fd77e36a6dbafc7006d969bed25cf
2020-09-08 10:56:08 -07:00
Jay Zhuang 27aa443a15 Add sst_file_dumper status check (#7315)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/7315

Test Plan:
`ASSERT_STATUS_CHECKED=1 make sst_dump_test && ./sst_dump_test`
And manually run `./sst_dump --file=*.sst` before and after the change.

Reviewed By: pdillinger

Differential Revision: D23361669

Pulled By: jay-zhuang

fbshipit-source-id: 5bf51a2a90ee35c8c679e5f604732ec2aef5949a
2020-09-04 19:26:42 -07:00
Andrew Kryczka af54c4092a fix SstFileWriter with dictionary compression (#7323)
Summary:
In block-based table builder, the cut-over from buffered to unbuffered
mode involves sampling the buffered blocks and generating a dictionary.
There was a bug where `SstFileWriter` passed zero as the `target_file_size`
causing the cutover to happen immediately, so there were no samples
available for generating the dictionary.

This PR changes the meaning of `target_file_size == 0` to mean buffer
the whole file before cutting over. It also adds dictionary compression
support to `sst_dump --command=recompress` for easy evaluation.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7323

Reviewed By: cheng-chang

Differential Revision: D23412158

Pulled By: ajkr

fbshipit-source-id: 3b232050e70ef3c2ee85a4b5f6fadb139c569873
2020-09-03 15:49:57 -07:00
Bingyi Sun 61d5a132c9 Fix typo: rename "bounary" to "boundary" in block.cc (#7328)
Summary:
Fix typo in comment for SeekForGetImpl().
Rename "bounary" to "boundary"

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7328

Reviewed By: riversand963

Differential Revision: D23439748

Pulled By: zhichao-cao

fbshipit-source-id: 83a34c417c71a3210ce54a090d76c4d5571313f3
2020-09-02 20:47:18 -07:00
Jay Zhuang c2485f2d81 Add buffer prefetch support for non directIO usecase (#7312)
Summary:
A new file interface `SupportPrefetch()` is added. When the user overrides it to `false`, an internal prefetch buffer will be used for readahead. Useful for non-directIO but FS doesn't have readahead support.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7312

Reviewed By: anand1976

Differential Revision: D23329847

Pulled By: jay-zhuang

fbshipit-source-id: 71cd4ce6f4a820840294e4e6aec111ab76175527
2020-08-27 18:16:53 -07:00
sdong 722814e357 Get() to fail with underlying failures in PartitionIndexReader::CacheDependencies() (#7297)
Summary:
Right now all I/O failures under PartitionIndexReader::CacheDependencies() is swallowed. This doesn't impact correctness but we've made a decision that any I/O error in read path now should be returned to users for awareness. Return errors in those cases instead.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7297

Test Plan: Add a new unit test that ingest errors in this code path and see Get() fails. Only one I/O path is hit in PartitionIndexReader::CacheDependencies(). Several option changes are attempt but not able to got other pread paths triggered. Not sure whether other failure cases would be even possible. Would rely on continuous stress test to validate it.

Reviewed By: anand1976

Differential Revision: D23257950

fbshipit-source-id: 859dbc92fa239996e1bb378329344d3d54168c03
2020-08-25 19:01:05 -07:00
mrambacher b7e1c5213f Add some simulator cache and block tracer tests to ASSERT_STATUS_CHECKED (#7305)
Summary:
More tests now pass.  When in doubt, I added a TODO comment to check what should happen with an ignored error.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7305

Reviewed By: akankshamahajan15

Differential Revision: D23301262

Pulled By: ajkr

fbshipit-source-id: 5f120edc7393560aefc0633250277bbc7e8de9e6
2020-08-24 16:43:31 -07:00
mrambacher e9befdebbf Add EnvTestWithParam::OptionsTest to the ASSERT_STATUS_CHECKED passes (#7283)
Summary:
This test uses database functionality and required more extensive work to get it to pass than the other tests.  The DB functionality required for this test now passes the check.

When it was unclear what the proper behavior was for unchecked status codes, a TODO was added.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7283

Reviewed By: akankshamahajan15

Differential Revision: D23251497

Pulled By: ajkr

fbshipit-source-id: 52b79629bdafa0a58de8ead1d1d66f141b331523
2020-08-20 19:18:35 -07:00
Levi Tamasi 9d6f48ec1d Clean up CompressBlock/CompressBlockInternal a bit (#7249)
Summary:
The patch cleans up and refactors `CompressBlock` and `CompressBlockInternal` a bit.
In particular, it does the following:
* It renames `CompressBlockInternal` to `CompressData` and moves it to `util/compression.h`,
where other general compression-related utilities are located. This will facilitate reuse in the
BlobDB write path.
* The signature of the method is changed so it now takes `compression_format_version`
(similarly to the compression library specific methods) instead of `format_version` (which is
specific to the block based table).
* `GetCompressionFormatForVersion` no longer takes `compression_type` as a parameter.
This parameter was only used in a (not entirely up-to-date) assertion; also, removing it
eliminates the need to ensure this precondition holds at all call sites.
* Does some minor cleanup in `CompressBlock`, for instance, it is now possible to pass
only one of `sampled_output_fast` and `sampled_output_slow`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7249

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D23087278

Pulled By: ltamasi

fbshipit-source-id: e6316e45baed8b4e7de7c1780c90501c2a3439b3
2020-08-12 18:25:48 -07:00
Yuhong Guo 5444942f15 Fix cmake build on MacOS (#7205)
Summary:
1. `std::random_shuffle` is deprecated and now we can use `std::shuffle`
```
/rocksdb/db/prefix_test.cc:590:12: error: 'random_shuffle<std::__1::__wrap_iter<unsigned long long *> >'
      is deprecated [-Werror,-Wdeprecated-declarations]
      std::random_shuffle(prefixes.begin(), prefixes.end());
           ^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/algorithm:2982:1: note:
      'random_shuffle<std::__1::__wrap_iter<unsigned long long *> >' has been explicitly marked deprecated here
_LIBCPP_DEPRECATED_IN_CXX14 void
^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/__config:1107:39: note: expanded from macro
      '_LIBCPP_DEPRECATED_IN_CXX14'
#  define _LIBCPP_DEPRECATED_IN_CXX14 _LIBCPP_DEPRECATED
                                      ^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/../include/c++/v1/__config:1090:48: note: expanded from macro
      '_LIBCPP_DEPRECATED'
#    define _LIBCPP_DEPRECATED __attribute__ ((deprecated))
```
2. `c_test` link error with `-DROCKSDB_BUILD_SHARED=OFF`:
```
[  7%] Linking CXX executable c_test
ld: library not found for -lrocksdb-shared
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[5]: *** [c_test] Error 1
make[4]: *** [CMakeFiles/c_test.dir/all] Error 2
make[4]: *** Waiting for unfinished jobs....
```

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7205

Reviewed By: ajkr

Differential Revision: D23030641

Pulled By: pdillinger

fbshipit-source-id: f270e50fc0b824ca1a0876ec5c65d33f55a72dd0
2020-08-10 10:48:05 -07:00
anand76 832b056a30 Enable IO timeouts for iterators (#7161)
Summary:
Introduce io_timeout in ReadOptions and enabled deadline/io_timeout for
Iterators.

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

Test Plan: New unit tests in db_basic_test

Reviewed By: riversand963

Differential Revision: D22687352

Pulled By: anand1976

fbshipit-source-id: 67bbb0e6d7ae80b256589244468494292538c6ec
2020-08-07 12:01:08 -07:00
sdong 5c1a544122 Clean up InternalIterator upper bound logic a little bit (#7200)
Summary:
IteratorIterator::IsOutOfBound() and IteratorIterator::MayBeOutOfUpperBound() are two functions that related to upper bound check. It is hard for users to reason about this complexity. Consolidate the two functions into one and assign an enum as results to improve readability.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7200

Test Plan: Run all existing test. Would run crash test with atomic for a while.

Reviewed By: anand1976

Differential Revision: D22833181

fbshipit-source-id: a0c724267056adbd0476bde74650e6c7226077e6
2020-08-05 10:44:57 -07:00
sdong 41c328fe57 Fix a perf regression that caused every key to go through upper bound check (#7209)
Summary:
https://github.com/facebook/rocksdb/pull/5289 introduces a performance regression that caused an upper bound check within every BlockBasedTableIterator::Next(). This is unnecessary if we've checked the boundary key for current block and it is within upper bound.

Fix the bug. Also rename the boolean to a enum so that the code is slightly better readable. The original regression was probably to fix a bug that the block upper bound check status is not reset after a new block is created. Fix it bug so that the regression can be avoided without hitting the bug.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7209

Test Plan: Run all existing tests. Will run atomic black box crash test for a while.

Reviewed By: anand1976

Differential Revision: D22859246

fbshipit-source-id: cbdad1f5e656c55fd8b71726d5a4f6cb53ff9140
2020-08-04 11:30:09 -07:00
Andrew Kryczka a4a4a2dabd dedup ReadOptions in iterator hierarchy (#7210)
Summary:
Previously, a `ReadOptions` object was stored in every `BlockBasedTableIterator`
and every `LevelIterator`. This redundancy consumes extra memory,
resulting in the `Arena` making more allocations, and iteration
observing worse cache performance.

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

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

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

Reviewed By: anand1976

Differential Revision: D22861323

Pulled By: ajkr

fbshipit-source-id: 54aebb3e89c872eeab0f5793b4b6e42878d093ce
2020-08-03 15:23:04 -07:00
sdong 692f6a3138 Implement NextAndGetResult() in memtable and level iterator (#7179)
Summary:
NextAndGetResult() is not implemented in memtable and is very simply implemented in level iterator. The result is that for a normal leveled iterator, performance regression will be observed for calling PrepareValue() for most iterator Next(). Mitigate the problem by implementing the function for both iterators. In level iterator, the implementation cannot be perfect as when calling file iterator's SeekToFirst() we don't have information about whether the value is prepared. Fortunately, the first key should not cause a big portion of the CPu.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7179

Test Plan: Run normal crash test for a while.

Reviewed By: anand1976

Differential Revision: D22783840

fbshipit-source-id: c19f45cdf21b756190adef97a3b66ccde3936e05
2020-07-29 09:45:21 -07:00
mrambacher d44cbc5314 Add hash of key/value checks when paranoid_file_checks=true (#7134)
Summary:
When paraoid_files_checks=true, a rolling key-value hash is generated and compared to what is written to the file.  If the values do not match, the SST file is rejected.

Code put in place for the check for both flush and compaction jobs.  Corresponding test added to corruption_test.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7134

Reviewed By: cheng-chang

Differential Revision: D22646149

fbshipit-source-id: 8fde1984a1a11edd3bd82a413acffc5ea7aa683f
2020-07-22 11:04:40 -07:00
Andrew Kryczka 643c863b72 minimize BlockIter comparator scope (#7149)
Summary:
PR https://github.com/facebook/rocksdb/issues/6944 transitioned `BlockIter` from using `Comparator*` to using
concrete `UserComparatorWrapper` and `InternalKeyComparator`. However,
adding them as instance variables to `BlockIter` was not optimal.
Bloating `BlockIter` caused the `ArenaWrappedDBIter`'s arena allocator to do more heap
allocations (in certain cases) which harmed performance of `DB::NewIterator()`. This PR
pushes down the concrete comparator objects to the point of usage, which
forces them to be on the stack. As a result, the `BlockIter` is back to
its original size prior to https://github.com/facebook/rocksdb/issues/6944 (actually a bit smaller since there
were two `Comparator*` before).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7149

Test Plan:
verified our internal `DB::NewIterator()`-heavy regression
test no longer reports regression.

Reviewed By: riversand963

Differential Revision: D22623189

Pulled By: ajkr

fbshipit-source-id: f6d69accfe5de51e0bd9874a480b32b29909bab6
2020-07-20 14:07:04 -07:00
mrambacher c7c7b07f06 More Makefile Cleanup (#7097)
Summary:
Cleans up some of the dependencies on test code in the Makefile while building tools:
- Moves the test::RandomString, DBBaseTest::RandomString into Random
- Moves the test::RandomHumanReadableString into Random
- Moves the DestroyDir method into file_utils
- Moves the SetupSyncPointsToMockDirectIO into sync_point.
- Moves the FaultInjection Env and FS classes under env

These changes allow all of the tools to build without dependencies on test_util, thereby simplifying the build dependencies.  By moving the FaultInjection code, the dependency in db_stress on different libraries for debug vs release was eliminated.

Tested both release and debug builds via Make and CMake for both static and shared libraries.

More work remains to clean up how the tools are built and remove some unnecessary dependencies.  There is also more work that should be done to get the Makefile and CMake to align in their builds -- what is in the libraries and the sizes of the executables are different.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7097

Reviewed By: riversand963

Differential Revision: D22463160

Pulled By: pdillinger

fbshipit-source-id: e19462b53324ab3f0b7c72459dbc73165cc382b2
2020-07-09 14:35:17 -07:00
Andrew Kryczka 82611ee25a save key comparisons in BlockIter::BinarySeek (#7068)
Summary:
This is a followup to https://github.com/facebook/rocksdb/issues/6646. In that PR, for simplicity I just appended a comparison against the 0th restart key in case `BinarySeek()`'s binary search landed at index 0. As a result there were `2/(N+1) + log_2(N)` key comparisons. This PR does it differently. Now we expand the binary search range by one so it also covers the case where target is at or before the restart key at index 0. As a result, it involves `log_2(N+1)` key comparisons.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7068

Test Plan:
ran readrandom with mostly default settings and counted key comparisons
using `PerfContext`.

before: `user_key_comparison_count = 28881965`
after: `user_key_comparison_count = 27823245`

setup command:

```
$ TEST_TMPDIR=/dev/shm/dbbench ./db_bench -benchmarks=fillrandom,compact -write_buffer_size=1048576 -target_file_size_base=1048576 -max_bytes_for_level_base=4194304 -max_background_jobs=12 -level_compaction_dynamic_level_bytes=true -num=10000000
```

benchmark command:

```
$ TEST_TMPDIR=/dev/shm/dbbench/ ./db_bench -use_existing_db=true -benchmarks=readrandom -disable_auto_compactions=true -num=10000000 -compression_type=none -reads=1000000 -perf_level=3
```

Reviewed By: anand1976

Differential Revision: D22357032

Pulled By: ajkr

fbshipit-source-id: 8b01e9c1c2a4e9d02fc9dfe16c1cc0327f8bdf24
2020-07-09 12:27:20 -07:00
Zitan Chen b35a2f9146 Fix GetFileDbIdentities (#7104)
Summary:
Although PR https://github.com/facebook/rocksdb/issues/7032 fixes the construction of the `SstFileDumper` in `GetFileDbIdentities` by setting a proper `Env` of the `Options` passed in the constructor, the file path was not corrected accordingly. This actually disables backup engine to use db session ids in the file names since the `db_session_id` is always empty.

Now it is fixed by setting the correct path in the construction of `SstFileDumper`. Furthermore, to preserve the Direct IO property that backup engine already has, parameter `EnvOptions` is added to `GetFileDbIdentities` and `SstFileDumper`.

The `BackupUsingDirectIO` test is updated accordingly.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7104

Test Plan: backupable_db_test and some manual tests.

Reviewed By: ajkr

Differential Revision: D22443245

Pulled By: gg814

fbshipit-source-id: 056a9bb8b82947c5e73d7c3fbb62bfe23af5e562
2020-07-09 08:37:59 -07:00
Akanksha Mahajan 54f171fe90 Update Flush policy in PartitionedIndexBuilder on switching from user-key to internal-key mode (#7096)
Summary:
When format_version is high enough to support user-key and
there are index entries for same user key that spans multiple data
blocks then it changes from user-key mode to internal-key mode. But the
flush policy is not reset to point to Block Builder of internal-keys.
After this switch, no entries are added to user key index partition
result, thus it never triggers flushing the block.

Fix: 1. After adding the entry in sub_builder_index_, if there is a switch
from user-key to internal-key, then flush policy is updated to point to
Block Builder of internal-keys index partition.
2. Set sub_builder_index_->seperator_is_key_plus_seq_ = true if
seperator_is_key_plus_seq_  is set to true so that subsequent partitions
can also use internal key mode.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7096

Test Plan: make check -j64

Reviewed By: ajkr

Differential Revision: D22416598

Pulled By: akankshamahajan15

fbshipit-source-id: 01fc2dc07ea1b32f8fb803995ebe6e9a3fbe67ac
2020-07-08 21:03:04 -07:00
rockeet b649d8cb97 Fixed Factory construct just for calling .Name() (#7080)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/7080

Reviewed By: riversand963

Differential Revision: D22412352

Pulled By: ajkr

fbshipit-source-id: 1d7f4c1621040a0130245139b52c3f4d3deac865
2020-07-08 11:54:00 -07:00
Andrew Kryczka dd29ad4223 Separate internal and user key comparators in `BlockIter` (#6944)
Summary:
Replace `BlockIter::comparator_` and `IndexBlockIter::user_comparator_wrapper_` with a concrete `UserComparatorWrapper` and `InternalKeyComparator`. The motivation for this change was the inconvenience of not knowing the concrete type of `BlockIter::comparator_`, which prevented calling specialized internal key comparison functions to optimize comparison of keys with global seqno applied.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/6944

Test Plan:
benchmark setup -- single file DBs, in-memory, no compression. "normal_db"
created by regular flush; "ingestion_db" created by ingesting a file. Both
DBs have same contents.

```
$ TEST_TMPDIR=/dev/shm/normal_db/ ./db_bench -benchmarks=fillrandom,compact -write_buffer_size=10485760000 -disable_auto_compactions=true -compression_type=none -num=1000000
$ ./ldb write_extern_sst ./tmp.sst --db=/dev/shm/ingestion_db/dbbench/ --compression_type=no --hex --create_if_missing < <(./sst_dump --command=scan --output_hex --file=/dev/shm/normal_db/dbbench/000007.sst | awk 'began {print "0x" substr($1, 2, length($1) - 2), "==>", "0x" $5} ; /^Sst file format: block-based/ {began=1}')
$ ./ldb ingest_extern_sst ./tmp.sst --db=/dev/shm/ingestion_db/dbbench/
```

benchmark run command:

```
$ TEST_TMPDIR=/dev/shm/$DB/ ./db_bench -benchmarks=seekrandom -seek_nexts=$SEEK_NEXT -use_existing_db=true -cache_index_and_filter_blocks=false -num=1000000 -cache_size=0 -threads=1 -reads=200000000 -mmap_read=1 -verify_checksum=false
```

results: perf improved marginally for ingestion_db and did not change significantly for normal_db:

SEEK_NEXT | DB | code | ops/sec | % change
-- | -- | -- | -- | --
0 | normal_db | master | 350880 |  
0 | normal_db | PR6944 | 351040 | 0.0
0 | ingestion_db | master | 343255 |  
0 | ingestion_db | PR6944 | 349424 | 1.8
10 | normal_db | master | 218711 |  
10 | normal_db | PR6944 | 217892 | -0.4
10 | ingestion_db | master | 220334 |  
10 | ingestion_db | PR6944 | 226437 | 2.8

Reviewed By: pdillinger

Differential Revision: D21924676

Pulled By: ajkr

fbshipit-source-id: ea4288a2eefa8112eb6c651a671c1de18c12e538
2020-07-07 17:26:16 -07:00
Peter Dillinger a680a7ea37 Un-revert #7049, revert #7022 (#7071)
Summary:
Even though local bisection gave me a clear signal (and still does) that reverting https://github.com/facebook/rocksdb/issues/7049 would fix the failures in MultiThreadedDBTest, https://github.com/facebook/rocksdb/issues/7022 seems to be the root cause. Reverting https://github.com/facebook/rocksdb/issues/7022 and keeping https://github.com/facebook/rocksdb/issues/7049 seems to fix the issue in local reproducer also. (Had these landed in opposite order, bisection would have found the root cause.)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7071

Reviewed By: akankshamahajan15

Differential Revision: D22362857

Pulled By: pdillinger

fbshipit-source-id: ed63df3d74e9d4ce1604de8fe43b216166c7a3f0
2020-07-02 13:30:41 -07:00
Akanksha Mahajan 5edfe3a3d8 Update Flush policy in PartitionedIndexBuilder on switching from user-key to internal-key mode (#7022)
Summary:
When format_version is high enough to support user-key and there are index entries for same user key that spans multiple data blocks then it changes from user-key mode to internal-key mode. But the flush policy is not reset to point to Block Builder of internal-keys. After this switch, no entries are added to user key index partition result, thus it never triggers flushing the block.

Fix: After adding the entry in sub_builder_index_, if there is a switch from user-key to internal-key, then flush policy is updated to point to Block Builder of internal-keys index partition.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7022

Test Plan:
1. make check -j64
           2. Added one unit test case

Reviewed By: ajkr

Differential Revision: D22197734

Pulled By: akankshamahajan15

fbshipit-source-id: d87e9e46bccab8e896ee6979d6b79c51f73d479e
2020-07-01 14:58:08 -07:00
Andrew Kryczka 8458532d58 Skip unnecessary allocation for mmap reads under 5000 bytes (#7043)
Summary:
With mmap enabled on an uncompressed file, we were previously always doing a heap allocation to obtain the scratch buffer for `RandomAccessFileReader::Read()`. However, that allocation was unnecessary as the underlying file reader returned a pointer into its mapped memory, not the provided scratch buffer. This PR makes passes the `BlockFetcher`'s inline buffer as the scratch buffer if the data block is small enough (less than `kDefaultStackBufferSize` bytes, currently 5000). Ideally we would not pass a scratch buffer at all for an mmap read; however, the `RandomAccessFile::Read()` API guarantees such a buffer is provided, and non-standard implementations may be relying on it even when `Options::allow_mmap_reads == true`. In that case, this PR still works but introduces an extra copy from the inline buffer to a heap buffer.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7043

Reviewed By: cheng-chang

Differential Revision: D22320606

Pulled By: ajkr

fbshipit-source-id: ad964dd23df34e07d979c6032c2dfe5454c98b52
2020-06-30 15:40:40 -07:00
Anand Ananthabhotla 9a5886bd8c Extend Get/MultiGet deadline support to table open (#6982)
Summary:
Current implementation of the ```read_options.deadline``` option only checks the deadline for random file reads during point lookups. This PR extends the checks to file opens, prefetches and preloads as part of table open.

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

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

Test Plan: Add new unit tests in db_basic_test

Reviewed By: riversand963

Differential Revision: D22219515

Pulled By: anand1976

fbshipit-source-id: 8a3b92f4a889808013838603aa3ca35229cd501b
2020-06-29 14:53:17 -07:00