Summary:
Currently, in direct IO mode, `MultiGet` retrieves the data blocks one by one instead of in parallel, see `BlockBasedTable::RetrieveMultipleBlocks`.
Since direct IO is supported in `RandomAccessFileReader::MultiRead` in https://github.com/facebook/rocksdb/pull/6446, this PR applies `MultiRead` to `MultiGet` so that the data blocks can be retrieved in parallel.
Also, in direct IO mode and when data blocks are compressed and need to uncompressed, this PR only allocates one continuous aligned buffer to hold the data blocks, and then directly uncompress the blocks to insert into block cache, there is no longer intermediate copies to scratch buffers.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6815
Test Plan:
1. added a new unit test `BlockBasedTableReaderTest::MultiGet`.
2. existing unit tests and stress tests contain tests against `MultiGet` in direct IO mode.
Reviewed By: anand1976
Differential Revision: D21426347
Pulled By: cheng-chang
fbshipit-source-id: b8446ae0e74152444ef9111e97f8e402ac31b24f
Summary:
sst_dump can issue many file reads from the file system. This doesn't work well with file systems without a OS cache, especially remote file systems. In order to mitigate this problem, several improvements are done:
1. --readahead_size is added, so that users can specify readahead size when scanning the data.
2. Force a 512KB tail readahead, which prevents three I/Os for footer, meta index and property blocks and hopefully index and filter blocks too.
3. Consoldiate SSTDump's I/Os before opening the file for read. Use the same file prefetch buffer.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6836
Test Plan: Add a test that covers this new feature.
Reviewed By: pdillinger
Differential Revision: D21516607
fbshipit-source-id: 3ae43526286f67b2f4a5bdedfbc92719d579b87e
Summary:
Currently there is no check for whether BlockBasedTableBuilder will expose
compression error status if compression fails during the table building.
This commit adds fake faulting compressors and a unit test to test such
cases.
This check finds 5 bugs, and this commit also fixes them:
1. Not handling compression failure well in
BlockBasedTableBuilder::BGWorkWriteRawBlock.
2. verify_compression failing in BlockBasedTableBuilder when used with ZSTD.
3. Wrongly passing the same reference of block contents to
BlockBasedTableBuilder::CompressAndVerifyBlock in parallel compression.
4. Wrongly setting block_rep->first_key_in_next_block to nullptr in
BlockBasedTableBuilder::EnterUnbuffered when there are still incoming data
blocks.
5. Not maintaining variables for compression ratio estimation and first_block
in BlockBasedTableBuilder::EnterUnbuffered.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6709
Reviewed By: ajkr
Differential Revision: D21236254
fbshipit-source-id: 101f6e62b2bac2b7be72be198adf93cd32a1ff46
Summary:
The error is assigning KeyContext::s to NotFound status in a
table reader for a "not found in this table" case, which skips searching
in later tables, like only a delete should. (The hash search index iterator
is the only one that can return status NotFound even if Valid() == false.)
This was detected by intermittent failure in
MultiThreadedDBTest.MultiThreaded/5, a kHashSearch configuration.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6821
Test Plan: modified existing unit test to reproduce problem
Reviewed By: anand1976
Differential Revision: D21450469
Pulled By: pdillinger
fbshipit-source-id: 7478003684d637dbd491cdac81468041a791be2c
Summary:
Add methods and constructors for handling enums to the OptionTypeInfo. This change allows enums to be converted/compared without adding a special "type" to the OptionType.
This change addresses a couple of issues:
- It allows new enumerated types to be added to the options without editing the OptionType base class (and related methods)
- It standardizes the procedure for adding enumerated types to the options, reducing potential mistakes
- It moves the enum maps to the location where they are used, allowing them to be static file members rather than global values
- It reduces the number of types and cases that need to be handled in the various OptionType methods
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6423
Reviewed By: siying
Differential Revision: D21408713
Pulled By: zhichao-cao
fbshipit-source-id: fc492af285d011822578b95d186a0fce25d35626
Summary:
There is no systematic mechanism to prevent BlockBasedTableBuilder's status to be set from non-OK to OK. Adding a mechanism to force this will help us prevent failures in the future.
The solution is to only make it possible to set the status code if the status code to set is not OK.
Since the status code passed to CompressAndVerifyBlock() is changed, a mini refactoring is done too so that the output arguments are changed from reference to pointers, based on Google C++ Style.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6776
Test Plan: Run all existing test.
Reviewed By: pdillinger
Differential Revision: D21314382
fbshipit-source-id: 27000c10f1e4c121661e026548d6882066409375
Summary:
Calculate ```IOOptions::timeout``` using ```ReadOptions::deadline``` and pass it to ```FileSystem::Read/FileSystem::MultiRead```. This allows us to impose a tighter bound on the time taken by Get/MultiGet on FileSystem/Envs that support IO timeouts. Even on those that don't support, check in ```RandomAccessFileReader::Read``` and ```MultiRead``` and return ```Status::TimedOut()``` if the deadline is exceeded.
For now, TableReader creation, which might do file opens and reads, are not covered. It will be implemented in another PR.
Tests:
Update existing unit tests to verify the correct timeout value is being passed
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6751
Reviewed By: riversand963
Differential Revision: D21285631
Pulled By: anand1976
fbshipit-source-id: d89af843e5a91ece866e87aa29438b52a65a8567
Summary:
An assertion that a char == a CompressionType (unsigned char)
originally cast from a char can fail if the original value is negative,
due to numeric promotion. The assertion should pass even if the value
is invalid CompressionType, because the callee
UncompressBlockContentsForCompressionType checks for that and reports
status appropriately.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6780
Test Plan:
Temporarily change kZSTD = 0x88 and see tests fail. Make this
change (in addition), and tests pass.
Reviewed By: siying
Differential Revision: D21328498
Pulled By: pdillinger
fbshipit-source-id: 61caf8d815581ce49261ecb7ab0f396e9ac4bb92
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
