Summary:
Existing multiGet() in java calls multi_get_helper() which then calls DB::std::vector MultiGet(). This doesn't take advantage of io_uring.
This change adds another JNI level method that runs a parallel code path using the DB::void MultiGet(), using ByteBuffers at the JNI level. We call it multiGetDirect(). In addition to using the io_uring path, this code internally returns pinned slices which we can copy out of into our direct byte buffers; this should reduce the overall number of copies in the code path to/from Java. Some jmh benchmark runs (100k keys, 1000 key multiGet) suggest that for value sizes > 1k, we see about a 20% performance improvement, although performance is slightly reduced for small value sizes, there's a little bit more overhead in the JNI methods.
Closes https://github.com/facebook/rocksdb/issues/8407
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9224
Reviewed By: mrambacher
Differential Revision: D32951754
Pulled By: jay-zhuang
fbshipit-source-id: 1f70df7334be2b6c42a9c8f92725f67c71631690
Summary:
Looks like some fields are not copied by the copy constructor.
Please confirm if it is a real issue!
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9166
Reviewed By: jay-zhuang
Differential Revision: D32532093
Pulled By: mrambacher
fbshipit-source-id: f636ef9425a530a8655947115160ae471916252b
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9266
This diff adds a new tag `CommitWithTimestamp`. Currently, there is no API to trigger writing
this tag to WAL, thus it is unavailable to users.
This is an ongoing effort to add user-defined timestamp support to write-committed transactions.
This diff also indicates all column families that may potentially participate in the same
transaction must either disable timestamp or have the same timestamp format, since
`CommitWithTimestamp` tag is followed by a single byte-array denoting the commit
timestamp of the transaction. We will enforce this checking in a future diff. We keep this
diff small.
Reviewed By: ltamasi
Differential Revision: D31721350
fbshipit-source-id: e1450811443647feb6ca01adec4c8aaae270ffc6
Summary:
**Context:**
Searching `TableProperties::properties_offsets` across the codebase reveals that internally it is only used to find the external SST file's global seqno offeset. Therefore we can narrow it down and replace this map property with a uint64_t property `external_sst_file_global_seqno_offset` to save memory usage related to table properties.
Note:
- See PR comments for discussion about potential impact on existing external usage of `TableProperties::properties_offsets`
- See PR comments for discussion on keeping external SST file global seqno's offset VS using a simple flag indicating seqno's existence.
**Summary:**
- Replaced `TableProperties::properties_offsets` with `TableProperties::external_sst_file_global_seqno_offset`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9212
Test Plan: - Relied on existing tests should be sufficient since `TableProperties::properties_offsets` existed before and should already be tested.
Reviewed By: ajkr
Differential Revision: D32665941
Pulled By: hx235
fbshipit-source-id: 718e44617346dc4f3b1276ee953e61c196277795
Summary:
Add the 3 read bytes counter to the Statistic, which will be used by storage tiering and get the information for files with different temperature.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9123
Test Plan: added new testing cases.
Reviewed By: siying
Differential Revision: D32154745
Pulled By: zhichao-cao
fbshipit-source-id: b7905d6dae469a72428742364ec07b634b6f15da
Summary:
It seems that an incorrect native source file entry was introduced in https://github.com/facebook/rocksdb/pull/8999. For some reason it appears that CI was not run against that PR, and so the problem was not detected.
This PR fixes the problem by removing the invalid entry, allowing RocksJava to build correctly again.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9147
Reviewed By: pdillinger
Differential Revision: D32300976
fbshipit-source-id: dbd763b806bacf0fc08f4deaf07c63d0a266c4cf
Summary:
Add clarification/extension to comments on max_total_wal_size and the Java wrapper MaxTotalWalSize to better explain the effect of the option on log file sizes.
Closes https://github.com/facebook/rocksdb/issues/5789
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9108
Reviewed By: pdillinger
Differential Revision: D32066640
Pulled By: mrambacher
fbshipit-source-id: 7d5affc87e4119019054af9c884a2ea01d68f5b7
Summary:
closes https://github.com/facebook/rocksdb/issues/5891
closes https://github.com/facebook/rocksdb/issues/2001
Java BytewiseComparator is now unsigned compliant, consistent with the default C++ comparator, which has always been thus. Consequently 2 tickets reporting the previous broken state can be closed.
This test confirms that the following issues were in fact resolved
by a change made between 6.2.2 and 6.22.1,
to wit https://github.com/facebook/rocksdb/commit/7242dae7
which as part of its effect, changed the Java bytewise comparators.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9019
Reviewed By: pdillinger
Differential Revision: D31610910
Pulled By: mrambacher
fbshipit-source-id: 664230f1377a1aa270136edd63eea2c206b907e9
Summary:
https://github.com/facebook/rocksdb/pull/7898 enable write buffer manager to stall write when memory_usage exceeds buffer_size, this is really useful for container running case to limit the memory usage. However, this feature is not visiable for rocksJava yet.
This PR targets to introduce this feature for rocksJava.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9076
Reviewed By: akankshamahajan15
Differential Revision: D31931092
Pulled By: anand1976
fbshipit-source-id: 5531c16a87598663a02368c07b5e13a503164578
Summary:
This PR adds support for building on s390x including updating travis CI. It uses the previous work in https://github.com/facebook/rocksdb/pull/6168 and adds some more changes to get all current tests (make check and jni tests) to pass. The tests were run with snappy, lz4, bzip2 and zstd all compiled in.
There are a few pieces still needed to get the travis build working that I don't think I can do. adamretter is this something you could help with?
1. A prebuilt https://rocksdb-deps.s3-us-west-2.amazonaws.com/cmake/cmake-3.14.5-Linux-s390x.deb package
2. A https://hub.docker.com/r/evolvedbinary/rocksjava s390x image
Not sure if there is more required for travis. Happy to help in any way I can.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8962
Reviewed By: mrambacher
Differential Revision: D31802198
Pulled By: pdillinger
fbshipit-source-id: 683511466fa6b505f85ba5a9964a268c6151f0c2
Summary:
Implementation of https://github.com/facebook/rocksdb/issues/8221, plus/including extension of Java options API to allow the get() of options from RocksDB. The extension allows more comprehensive testing of options at the Java side, by validating that the options are set at the C++ side.
Variations on methods:
MutableColumnFamilyOptions.MutableColumnFamilyOptionsBuilder getOptions()
MutableDBOptions.MutableDBOptionsBuilder getDBOptions()
retrieve the options via RocksDB C++ interfaces, and parse the resulting string into one of the Java-style option objects.
This necessitated generalising the parsing of option strings in Java, which now parses the full range of option strings returned by the C++ interface, rather than a useful subset. This necessitates the list-separator being changed to :(colon) from , (comma).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8999
Reviewed By: jay-zhuang
Differential Revision: D31655487
Pulled By: ltamasi
fbshipit-source-id: c38e98145c81c61dc38238b0df580db176ce4efd
Summary:
closes https://github.com/facebook/rocksdb/issues/8039
Unnecessary use of multiple local JNI references at the same time, 1 per key, was limiting the size of the key array. The local references don't need to be held simultaneously, so if we rearrange the code we can make it work for bigger key arrays.
Incidentally, make errors throw helpful exception messages rather than returning a null pointer.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9012
Reviewed By: mrambacher
Differential Revision: D31580862
Pulled By: jay-zhuang
fbshipit-source-id: ce05831d52ede332e1b20e74d2dc621d219b9616
Summary:
* Don't hardcode namespace rocksdb (use ROCKSDB_NAMESPACE)
* Don't #include <rocksdb/...> (use double quotes)
* Support putting NOCOMMIT (any case) in source code that should not be
committed/pushed in current state.
These will be run with `make check` and in GitHub actions
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8821
Test Plan: existing tests, manually try out new checks
Reviewed By: zhichao-cao
Differential Revision: D30791726
Pulled By: pdillinger
fbshipit-source-id: 399c883f312be24d9e55c58951d4013e18429d92
Summary:
Gets `Statistics` from the options associated with the `DB` undergoing backup, and populates new ticker stats with the thread-local `IOContext` read/write counters for the threads doing backup work.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8819
Reviewed By: pdillinger
Differential Revision: D30779238
Pulled By: ajkr
fbshipit-source-id: 75ccafc355f90906df5cf80367f7245b985772d8
Summary:
- Clarified some comments on compatibility for adding new ticker stats
- Added read I/O stats for `VerifyChecksum()` and `VerifyFileChecksums()` APIs
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8741
Test Plan: new unit test
Reviewed By: zhichao-cao
Differential Revision: D30708578
Pulled By: ajkr
fbshipit-source-id: d06b961f7e199ae92c266b683e39870aa8f63449
Summary:
* FullKey and ParseFullKey appear to serve no purpose in the public API
(or anything else) so removed. Only use in one test updated.
* NumberToString serves no purpose vs. ToString so removed, numerous
calls updated
* Remove unnecessary forward declarations in metadata.h by re-arranging
class definitions.
* Remove some unneeded semicolons
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8736
Test Plan: existing tests
Reviewed By: mrambacher
Differential Revision: D30700039
Pulled By: pdillinger
fbshipit-source-id: 1e436a576f511a6ed8b4d97af7cc8216bc729af2
Summary:
Add a stat for secondary cache hits. The ```Cache::Lookup``` API had an unused ```stats``` parameter. This PR uses that to pass the pointer to a ```Statistics``` object that ```LRUCache``` uses to record the stat.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8666
Test Plan: Update a unit test in lru_cache_test
Reviewed By: zhichao-cao
Differential Revision: D30353816
Pulled By: anand1976
fbshipit-source-id: 2046f78b460428877a26ffdd2bb914ae47dfbe77
Summary:
Some FIFO users want to keep the data for longer, but the old data is rarely accessed. This feature allows users to configure FIFO compaction so that data older than a threshold is moved to a warm storage tier.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8310
Test Plan: Add several unit tests.
Reviewed By: ajkr
Differential Revision: D28493792
fbshipit-source-id: c14824ea634814dee5278b449ab5c98b6e0b5501
Summary:
By default, the low priority pool is not the flush pool, so calling `Env#setBackgroundThreads` without providing a priority will not do what the caller expected.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8576
Reviewed By: ajkr
Differential Revision: D29925154
Pulled By: mrambacher
fbshipit-source-id: cd7211fc374e7d9929a9b88ea0a5ba8134b76099
Summary:
An arbitrary string can be used as a delimiter in StringAppend merge operator
flavor. In particular, it allows using an empty string, combining binary values for
the same key byte-to-byte one next to another.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8536
Reviewed By: mrambacher
Differential Revision: D29962120
Pulled By: zhichao-cao
fbshipit-source-id: 4ef5d846a47835cf428a11200409e30e2dbffc4f
Summary:
I previously didn't notice the DB mutex was being held during
block cache entry stat scans, probably because I primarily checked for
read performance regressions, because they require the block cache and
are traditionally latency-sensitive.
This change does some refactoring to avoid holding DB mutex and to
avoid triggering and waiting for a scan in GetProperty("rocksdb.cfstats").
Some tests have to be updated because now the stats collector is
populated in the Cache aggressively on DB startup rather than lazily.
(I hope to clean up some of this added complexity in the future.)
This change also ensures proper treatment of need_out_of_mutex for
non-int DB properties.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8538
Test Plan:
Added unit test logic that uses sync points to fail if the DB mutex
is held during a scan, covering the various ways that a scan might be
triggered.
Performance test - the known impact to holding the DB mutex is on
TransactionDB, and the easiest way to see the impact is to hack the
scan code to almost always miss and take an artificially long time
scanning. Here I've injected an unconditional 5s sleep at the call to
ApplyToAllEntries.
Before (hacked):
$ TEST_TMPDIR=/dev/shm ./db_bench.base_xxx -benchmarks=randomtransaction,stats -cache_index_and_filter_blocks=1 -bloom_bits=10 -partition_index_and_filters=1 -duration=30 -stats_dump_period_sec=12 -cache_size=100000000 -statistics -transaction_db 2>&1 | egrep 'db.db.write.micros|micros/op'
randomtransaction : 433.219 micros/op 2308 ops/sec; 0.1 MB/s ( transactions:78999 aborts:0)
rocksdb.db.write.micros P50 : 16.135883 P95 : 36.622503 P99 : 66.036115 P100 : 5000614.000000 COUNT : 149677 SUM : 8364856
$ TEST_TMPDIR=/dev/shm ./db_bench.base_xxx -benchmarks=randomtransaction,stats -cache_index_and_filter_blocks=1 -bloom_bits=10 -partition_index_and_filters=1 -duration=30 -stats_dump_period_sec=12 -cache_size=100000000 -statistics -transaction_db 2>&1 | egrep 'db.db.write.micros|micros/op'
randomtransaction : 448.802 micros/op 2228 ops/sec; 0.1 MB/s ( transactions:75999 aborts:0)
rocksdb.db.write.micros P50 : 16.629221 P95 : 37.320607 P99 : 72.144341 P100 : 5000871.000000 COUNT : 143995 SUM : 13472323
Notice the 5s P100 write time.
After (hacked):
$ TEST_TMPDIR=/dev/shm ./db_bench.new_xxx -benchmarks=randomtransaction,stats -cache_index_and_filter_blocks=1 -bloom_bits=10 -partition_index_and_filters=1 -duration=30 -stats_dump_period_sec=12 -cache_size=100000000 -statistics -transaction_db 2>&1 | egrep 'db.db.write.micros|micros/op'
randomtransaction : 303.645 micros/op 3293 ops/sec; 0.1 MB/s ( transactions:98999 aborts:0)
rocksdb.db.write.micros P50 : 16.061871 P95 : 33.978834 P99 : 60.018017 P100 : 616315.000000 COUNT : 187619 SUM : 4097407
$ TEST_TMPDIR=/dev/shm ./db_bench.new_xxx -benchmarks=randomtransaction,stats -cache_index_and_filter_blocks=1 -bloom_bits=10 -partition_index_and_filters=1 -duration=30 -stats_dump_period_sec=12 -cache_size=100000000 -statistics -transaction_db 2>&1 | egrep 'db.db.write.micros|micros/op'
randomtransaction : 310.383 micros/op 3221 ops/sec; 0.1 MB/s ( transactions:96999 aborts:0)
rocksdb.db.write.micros P50 : 16.270026 P95 : 35.786844 P99 : 64.302878 P100 : 603088.000000 COUNT : 183819 SUM : 4095918
P100 write is now ~0.6s. Not good, but it's the same even if I completely bypass all the scanning code:
$ TEST_TMPDIR=/dev/shm ./db_bench.new_skip -benchmarks=randomtransaction,stats -cache_index_and_filter_blocks=1 -bloom_bits=10 -partition_index_and_filters=1 -duration=30 -stats_dump_period_sec=12 -cache_size=100000000 -statistics -transaction_db 2>&1 | egrep 'db.db.write.micros|micros/op'
randomtransaction : 311.365 micros/op 3211 ops/sec; 0.1 MB/s ( transactions:96999 aborts:0)
rocksdb.db.write.micros P50 : 16.274362 P95 : 36.221184 P99 : 68.809783 P100 : 649808.000000 COUNT : 183819 SUM : 4156767
$ TEST_TMPDIR=/dev/shm ./db_bench.new_skip -benchmarks=randomtransaction,stats -cache_index_and_filter_blocks=1 -bloom_bits=10 -partition_index_and_filters=1 -duration=30 -stats_dump_period_sec=12 -cache_size=100000000 -statistics -transaction_db 2>&1 | egrep 'db.db.write.micros|micros/op'
randomtransaction : 308.395 micros/op 3242 ops/sec; 0.1 MB/s ( transactions:97999 aborts:0)
rocksdb.db.write.micros P50 : 16.106222 P95 : 37.202403 P99 : 67.081875 P100 : 598091.000000 COUNT : 185714 SUM : 4098832
No substantial difference.
Reviewed By: siying
Differential Revision: D29738847
Pulled By: pdillinger
fbshipit-source-id: 1c5c155f5a1b62e4fea0fd4eeb515a8b7474027b
Summary:
**Summary**:
2 new statistics counters are added to RocksDB: `MEMTABLE_PAYLOAD_BYTES_AT_FLUSH` and `MEMTABLE_GARBAGE_BYTES_AT_FLUSH`. The former tracks how many raw bytes of useful data are present on the memtable at flush time, whereas the latter is tracks how many of these raw bytes are considered garbage, meaning that they ended up not being imported on the SSTables resulting from the flush operations.
**Unit test**: run `make db_flush_test -j$(nproc); ./db_flush_test` to run the unit test.
This executable includes 3 tests, that test support and correct stat calculations for workloads with inserts, deletes, and DeleteRanges. The parameters are set such that the workloads are performed on a single memtable, and a single SSTable is created as a result of the flush operation. The flush operation is manually called in the test file. The tests verify that the values of these 2 statistics counters introduced in this PR can be exactly predicted, showing that we have a full understanding of the underlying operations.
**Performance testing**:
`./db_bench -statistics -benchmarks=fillrandom -num=10000000` repeated 10 times.
Timing done using "date" function in a bash script.
_Results_:
Original Rocksdb fork: mean 66.6 sec, std 1.18 sec.
This feature branch: mean 67.4 sec, std 1.35 sec.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8411
Reviewed By: akankshamahajan15
Differential Revision: D29150629
Pulled By: bjlemaire
fbshipit-source-id: 7b3c2e86d50c6aa34fa50fd134282eacb543a5b1
Summary:
The ImmutableCFOptions contained a bunch of fields that belonged to the ImmutableDBOptions. This change cleans that up by introducing an ImmutableOptions struct. Following the pattern of Options struct, this class inherits from the DB and CFOption structs (of the Immutable form).
Only one structural change (the ImmutableCFOptions::fs was changed to a shared_ptr from a raw one) is in this PR. All of the other changes involve moving the member variables from the ImmutableCFOptions into the ImmutableOptions and changing member variables or function parameters as required for compilation purposes.
Follow-on PRs may do a further clean-up of the code, such as renaming variables (such as "ImmutableOptions cf_options") and potentially eliminating un-needed function parameters (there is no longer a need to pass both an ImmutableDBOptions and an ImmutableOptions to a function).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8262
Reviewed By: pdillinger
Differential Revision: D28226540
Pulled By: mrambacher
fbshipit-source-id: 18ae71eadc879dedbe38b1eb8e6f9ff5c7147dbf
Summary:
In a distributed environment, a file `rename()` operation can succeed on server (remote)
side, but the client can somehow return non-ok status to RocksDB. Possible reasons include
network partition, connection issue, etc. This happens in `rocksdb::SetCurrentFile()`, which
can be called in `LogAndApply() -> ProcessManifestWrites()` if RocksDB tries to switch to a
new MANIFEST. We currently always delete the new MANIFEST if an error occurs.
This is problematic in distributed world. If the server-side successfully updates the CURRENT
file via renaming, then a subsequent `DB::Open()` will try to look for the new MANIFEST and fail.
As a fix, we can track the execution result of IO operations on the new MANIFEST.
- If IO operations on the new MANIFEST fail, then we know the CURRENT must point to the original
MANIFEST. Therefore, it is safe to remove the new MANIFEST.
- If IO operations on the new MANIFEST all succeed, but somehow we end up in the clean up
code block, then we do not know whether CURRENT points to the new or old MANIFEST. (For local
POSIX-compliant FS, it should still point to old MANIFEST, but it does not matter if we keep the
new MANIFEST.) Therefore, we keep the new MANIFEST.
- Any future `LogAndApply()` will switch to a new MANIFEST and update CURRENT.
- If process reopens the db immediately after the failure, then the CURRENT file can point
to either the new MANIFEST or the old one, both of which exist. Therefore, recovery can
succeed and ignore the other.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8192
Test Plan: make check
Reviewed By: zhichao-cao
Differential Revision: D27804648
Pulled By: riversand963
fbshipit-source-id: 9c16f2a5ce41bc6aadf085e48449b19ede8423e4
Summary:
Added `TableProperties::{fast,slow}_compression_estimated_data_size`.
These properties are present in block-based tables when
`ColumnFamilyOptions::sample_for_compression > 0` and the necessary
compression library is supported when the file is generated. They
contain estimates of what `TableProperties::data_size` would be if the
"fast"/"slow" compression library had been used instead. One
limitation is we do not record exactly which "fast" (ZSTD or Zlib)
or "slow" (LZ4 or Snappy) compression library produced the result.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8139
Test Plan:
- new unit test
- ran `db_bench` with `sample_for_compression=1`; verified the `data_size` property matches the `{slow,fast}_compression_estimated_data_size` when the same compression type is used for the output file compression and the sampled compression
Reviewed By: riversand963
Differential Revision: D27454338
Pulled By: ajkr
fbshipit-source-id: 9529293de93ddac7f03b2e149d746e9f634abac4
Summary:
Which should return 2 long instead of an array.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8098
Reviewed By: mrambacher
Differential Revision: D27308741
Pulled By: jay-zhuang
fbshipit-source-id: 44beea2bd28cf6779b048bebc98f2426fe95e25c
Summary:
This is a small fix to what I think is a mistype in two comments in `DBOptionsInterface.java`. If it was not an error, feel free to close.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8086
Reviewed By: ajkr
Differential Revision: D27260488
Pulled By: mrambacher
fbshipit-source-id: 469daadaf6039d5b5187132b8e0c7c3672842f21
Summary:
Add statistics and info log for error handler: counters for bg error, bg io error, bg retryable io error, auto resume, auto resume total retry, and auto resume sucess; Histogram for auto resume retry count in each recovery call.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8050
Test Plan: make check and add test to error_handler_fs_test
Reviewed By: anand1976
Differential Revision: D26990565
Pulled By: zhichao-cao
fbshipit-source-id: 49f71e8ea4e9db8b189943976404205b56ab883f
Summary:
support getUsage and getPinnedUsage in JavaAPI for Cache
also fix a typo in LRUCacheTest.java that the highPriPoolRatio is not valid(set 5, I guess it means 0.05)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7925
Reviewed By: mrambacher
Differential Revision: D26900241
Pulled By: ajkr
fbshipit-source-id: 735d1e40a16fa8919c89c7c7154ba7f81208ec33
Summary:
Fixes 3 minor Javadoc copy-paste errors in the `RocksDB#newIterator()` and `Transaction#getIterator()` variants that take a column family handle but are talking about iterating over "the database" or "the default column family".
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8034
Reviewed By: jay-zhuang
Differential Revision: D26877667
Pulled By: mrambacher
fbshipit-source-id: 95dd95b667c496e389f221acc9a91b340e4b63bf
Summary:
The variable `byteCompressionType` is only assigned values of primitive type and is never 'null', but it is declared with the boxed type 'Byte'.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7981
Reviewed By: ajkr
Differential Revision: D26546600
Pulled By: jay-zhuang
fbshipit-source-id: 07b579cdfcfc2262a448ca3626e216416fd05892
Summary:
Haven't seen any production issues with new Bloom filter and
it's now > 1 year old (added in 6.6.0).
Updated check_format_compatible.sh and HISTORY.md
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8017
Test Plan: tests updated (or prior bugs fixed)
Reviewed By: ajkr
Differential Revision: D26762197
Pulled By: pdillinger
fbshipit-source-id: 0e755c46b443087c1544da0fd545beb9c403d1c2
Summary:
For dictionary compression, we need to collect some representative samples of the data to be compressed, which we use to either generate or train (when `CompressionOptions::zstd_max_train_bytes > 0`) a dictionary. Previously, the strategy was to buffer all the data blocks during flush, and up to the target file size during compaction. That strategy allowed us to randomly pick samples from as wide a range as possible that'd be guaranteed to land in a single output file.
However, some users try to make huge files in memory-constrained environments, where this strategy can cause OOM. This PR introduces an option, `CompressionOptions::max_dict_buffer_bytes`, that limits how much data blocks are buffered before we switch to unbuffered mode (which means creating the per-SST dictionary, writing out the buffered data, and compressing/writing new blocks as soon as they are built). It is not strict as we currently buffer more than just data blocks -- also keys are buffered. But it does make a step towards giving users predictable memory usage.
Related changes include:
- Changed sampling for dictionary compression to select unique data blocks when there is limited availability of data blocks
- Made use of `BlockBuilder::SwapAndReset()` to save an allocation+memcpy when buffering data blocks for building a dictionary
- Changed `ParseBoolean()` to accept an input containing characters after the boolean. This is necessary since, with this PR, a value for `CompressionOptions::enabled` is no longer necessarily the final component in the `CompressionOptions` string.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7970
Test Plan:
- updated `CompressionOptions` unit tests to verify limit is respected (to the extent expected in the current implementation) in various scenarios of flush/compaction to bottommost/non-bottommost level
- looked at jemalloc heap profiles right before and after switching to unbuffered mode during flush/compaction. Verified memory usage in buffering is proportional to the limit set.
Reviewed By: pdillinger
Differential Revision: D26467994
Pulled By: ajkr
fbshipit-source-id: 3da4ef9fba59974e4ef40e40c01611002c861465
Andrea Cavalli