Summary:
XXH3 - latest hash function that is extremely fast on large
data, easily faster than crc32c on most any x86_64 hardware. In
integrating this hash function, I have handled the compression type byte
in a non-standard way to avoid using the streaming API (extra data
movement and active code size because of hash function complexity). This
approach got a thumbs-up from Yann Collet.
Existing functionality change:
* reject bad ChecksumType in options with InvalidArgument
This change split off from https://github.com/facebook/rocksdb/issues/9058 because context-aware checksum is
likely to be handled through different configuration than ChecksumType.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9069
Test Plan:
tests updated, and substantially expanded. Unit tests now check
that we don't accidentally change the values generated by the checksum
algorithms ("schema test") and that we properly handle
invalid/unrecognized checksum types in options or in file footer.
DBTestBase::ChangeOptions (etc.) updated from two to one configuration
changing from default CRC32c ChecksumType. The point of this test code
is to detect possible interactions among features, and the likelihood of
some bad interaction being detected by including configurations other
than XXH3 and CRC32c--and then not detected by stress/crash test--is
extremely low.
Stress/crash test also updated (manual run long enough to see it accepts
new checksum type). db_bench also updated for microbenchmarking
checksums.
### Performance microbenchmark (PORTABLE=0 DEBUG_LEVEL=0, Broadwell processor)
./db_bench -benchmarks=crc32c,xxhash,xxhash64,xxh3,crc32c,xxhash,xxhash64,xxh3,crc32c,xxhash,xxhash64,xxh3
crc32c : 0.200 micros/op 5005220 ops/sec; 19551.6 MB/s (4096 per op)
xxhash : 0.807 micros/op 1238408 ops/sec; 4837.5 MB/s (4096 per op)
xxhash64 : 0.421 micros/op 2376514 ops/sec; 9283.3 MB/s (4096 per op)
xxh3 : 0.171 micros/op 5858391 ops/sec; 22884.3 MB/s (4096 per op)
crc32c : 0.206 micros/op 4859566 ops/sec; 18982.7 MB/s (4096 per op)
xxhash : 0.793 micros/op 1260850 ops/sec; 4925.2 MB/s (4096 per op)
xxhash64 : 0.410 micros/op 2439182 ops/sec; 9528.1 MB/s (4096 per op)
xxh3 : 0.161 micros/op 6202872 ops/sec; 24230.0 MB/s (4096 per op)
crc32c : 0.203 micros/op 4924686 ops/sec; 19237.1 MB/s (4096 per op)
xxhash : 0.839 micros/op 1192388 ops/sec; 4657.8 MB/s (4096 per op)
xxhash64 : 0.424 micros/op 2357391 ops/sec; 9208.6 MB/s (4096 per op)
xxh3 : 0.162 micros/op 6182678 ops/sec; 24151.1 MB/s (4096 per op)
As you can see, especially once warmed up, xxh3 is fastest.
### Performance macrobenchmark (PORTABLE=0 DEBUG_LEVEL=0, Broadwell processor)
Test
for I in `seq 1 50`; do for CHK in 0 1 2 3 4; do TEST_TMPDIR=/dev/shm/rocksdb$CHK ./db_bench -benchmarks=fillseq -memtablerep=vector -allow_concurrent_memtable_write=false -num=30000000 -checksum_type=$CHK 2>&1 | grep 'micros/op' | tee -a results-$CHK & done; wait; done
Results (ops/sec)
for FILE in results*; do echo -n "$FILE "; awk '{ s += $5; c++; } END { print 1.0 * s / c; }' < $FILE; done
results-0 252118 # kNoChecksum
results-1 251588 # kCRC32c
results-2 251863 # kxxHash
results-3 252016 # kxxHash64
results-4 252038 # kXXH3
Reviewed By: mrambacher
Differential Revision: D31905249
Pulled By: pdillinger
fbshipit-source-id: cb9b998ebe2523fc7c400eedf62124a78bf4b4d1
Summary:
Somewhat confusingly, index and filter partition blocks are
never owned by table readers, even with
cache_index_and_filter_blocks=false. They still go into block cache
(possibly pinned by table reader) if there is a block cache. If no block
cache, they are only loaded transiently on demand.
This PR primarily clarifies the options APIs and some internal code
comments.
Also, this closes a hypothetical data corruption vulnerability where
some but not all index partitions are pinned. I haven't been able to
reproduce a case where it can happen (the failure seems to propagate
to abort table open) but it's worth patching nonetheless.
Fixes https://github.com/facebook/rocksdb/issues/8979
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9068
Test Plan:
existing tests :-/ I could cover the new code using sync
points, but then I'd have to very carefully relax my `assert(false)`
Reviewed By: ajkr
Differential Revision: D31898284
Pulled By: pdillinger
fbshipit-source-id: f2511a7d3a36bc04b627935d8e6cfea6422f98be
Summary:
Currently, if Secondary Cache is provided to the lru cache, it is used by default. We add CacheTier to advanced_options.h to describe the cache tier we used. Add a `lowest_used_cache_tier` option to `DBOptions` (immutable) and pass it to BlockBasedTableReader to decide if secondary cache will be used or not. By default it is `CacheTier::kNonVolatileTier`, which means, we always use both block cache (kVolatileTier) and secondary cache (kNonVolatileTier). By set it to `CacheTier::kVolatileTier`, the DB will not use the secondary cache.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9050
Test Plan: added new tests
Reviewed By: anand1976
Differential Revision: D31744769
Pulled By: zhichao-cao
fbshipit-source-id: a0575ebd23e1c6dfcfc2b4c8578764e73b15bce6
Summary:
... by bypassing tracking of last_key in BlockBuilder when
last_key is already known (for BlockBasedTableBuilder::data_block).
I tried extracting a base class of BlockBuilder without the last_key
tracking at all, but that became complicated by NewFlushBlockPolicy() in
the public API referencing BlockBuilder, which would need to be the base
class, and I don't want to replace nearly all the internal references to
BlockBuilder.
Possible follow-up:
* Investigate / consider using AddWithLastKey in more places
This improvement should stack with https://github.com/facebook/rocksdb/issues/9039
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9040
Test Plan:
TEST_TMPDIR=/dev/shm/rocksdb1 ./db_bench -benchmarks=fillseq -memtablerep=vector -allow_concurrent_memtable_write=false -num=50000000
Compiled with DEBUG_LEVEL=0
Test vs. control runs simulaneous for better accuracy, units = ops/sec
Run 1: 278929 vs. 267799 (+4.2%)
Run 2: 281836 vs. 267432 (+5.4%)
Run 3: 278279 vs. 270454 (+2.9%)
(This benchmark is chosen to have detectable signal-to-noise, not to
represent expected improvement percent on real workloads.)
Reviewed By: mrambacher
Differential Revision: D31706033
Pulled By: pdillinger
fbshipit-source-id: 8a50fe6fefdd67b6d7665ffa687bbdcf5ad0d5ec
Summary:
Primarily, this change reserves space in the std::string for building
the next block once a block is finished, using `block_size` as
reservation size. Note: also tried reusing same std::string in the
common "unbuffered" path but that showed no benefit or regression.
Secondarily, this slightly reduces the work in resetting `restarts_`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9039
Test Plan:
TEST_TMPDIR=/dev/shm/rocksdb1 ./db_bench -benchmarks=fillseq -memtablerep=vector -allow_concurrent_memtable_write=false -num=50000000
Compiled with DEBUG_LEVEL=0
Test vs. control runs simulaneous for better accuracy, units = ops/sec
Run 1, Primary change only: 292697 vs. 280267 (+4.4%)
Run 2, Primary change only: 288763 vs. 279621 (+3.3%)
Run 1, Secondary change only: 260065 vs. 254232 (+2.3%)
Run 2, Secondary change only: 275925 vs. 272248 (+1.4%)
Run 1, Both changes: 284890 vs. 270372 (+5.3%)
Run 2, Both changes: 263511 vs. 258188 (+2.0%)
Reviewed By: zhichao-cao
Differential Revision: D31701253
Pulled By: pdillinger
fbshipit-source-id: 7e40810afbb98e6b6446955e77bda59e69b19ffd
Summary:
This header file was including everything and the kitchen sink when it did not need to. This resulted in many places including this header when they needed other pieces instead.
Cleaned up this header to only include what was needed and fixed up the remaining code to include what was now missing.
Hopefully, this sort of code hygiene cleanup will speed up the builds...
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8930
Reviewed By: pdillinger
Differential Revision: D31142788
Pulled By: mrambacher
fbshipit-source-id: 6b45de3f300750c79f751f6227dece9cfd44085d
Summary:
Context:
Exposing the level of the sst file (i.e, table) where it is created in `TablePropertiesCollectorFactory::Context` allows users of `TablePropertiesCollectorFactory` to customize some implementation details of `TablePropertiesCollectorFactory` and `TablePropertiesCollector` based on the level of creation. For example, `TablePropertiesCollector::NeedCompact()` can return different values based on level of creation.
- Declared an extra field `level_at_creation` in `TablePropertiesCollectorFactory::Context`
- Allowed `level_at_creation` to be passed in as an argument in `IntTblPropCollectorFactory::CreateIntTblPropCollector()` and `UserKeyTablePropertiesCollectorFactory::CreateIntTblPropCollector()`, the latter of which is an internal wrapper of user's passed-in `TablePropertiesCollectorFactory::CreateTablePropertiesCollector()` used in table-building process
- Called `IntTblPropCollectorFactory::CreateIntTblPropCollector()` with `level_at_creation` passed into both `BlockBasedTableBuilder` and `PlainTableBuilder`
- `PlainTableBuilder` previously did not capture `level_at_creation` from `TableBuilderOptions` in `PlainTableFactory`. In order for it to call the method with this parameter, this PR also made `PlainTableBuilder` capture `level_at_creation` as a required parameter
- Called `IntTblPropCollectorFactory::CreateIntTblPropCollector()` with `level_at_creation` its overridden functions in its derived classes, including `RegularKeysStartWithAFactory::CreateIntTblPropCollector()` in `table_properties_collector_test.cc`, `SstFileWriterPropertiesCollectorFactory::CreateIntTblPropCollector()` in `sst_file_writer_collectors.h`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8919
Test Plan:
- Passed the added assertion for `context.level_at_creation`
- Passed existing tests
- Run `Make` to make sure adding a required parameter to `PlainTableBuilder`'s constructor does not break anything
Reviewed By: anand1976
Differential Revision: D30951729
Pulled By: hx235
fbshipit-source-id: c4a0173b0d9344a4cf47e1b987d759c1c73cb474
Summary:
Made SliceTransform into a Customizable class.
Would be nice to write a test that stored and used a custom transform in an SST table.
There are a set of tests (DBBlockFliterTest.PrefixExtractor*, SamePrefixTest.InDomainTest, PrefixTest.PrefixAndWholeKeyTest that run the same with or without a SliceTransform/PrefixFilter. Is this expected?
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8641
Reviewed By: zhichao-cao
Differential Revision: D31142793
Pulled By: mrambacher
fbshipit-source-id: bb08672fccbfdc263dcae21f25a62307e1facda1
Summary:
kFlushOnly currently means "always" except in the case of
remote compaction. This makes it flushes only.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8750
Test Plan: test updated
Reviewed By: akankshamahajan15
Differential Revision: D30968034
Pulled By: pdillinger
fbshipit-source-id: 5dbd24dde18852a0e937a540995fba9bfbe89037
Summary:
Potential bugs in the IO uring implementation can cause bad data to be returned in the completion queue. Add some checks in the PosixRandomAccessFile::MultiRead completion handling code to catch such errors and fail the entire MultiRead. Also log some diagnostic messages and stack trace.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8894
Reviewed By: siying, pdillinger
Differential Revision: D30826982
Pulled By: anand1976
fbshipit-source-id: af91815ac760e095d6cc0466cf8bd5c10167fd15
Summary:
It's always annoying to find a header does not include its own
dependencies and only works when included after other includes. This
change adds `make check-headers` which validates that each header can
be included at the top of a file. Some headers are excluded e.g. because
of platform or external dependencies.
rocksdb_namespace.h had to be re-worked slightly to enable checking for
failure to include it. (ROCKSDB_NAMESPACE is a valid namespace name.)
Fixes mostly involve adding and cleaning up #includes, but for
FileTraceWriter, a constructor was out-of-lined to make a forward
declaration sufficient.
This check is not currently run with `make check` but is added to
CircleCI build-linux-unity since that one is already relatively fast.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8893
Test Plan: existing tests and resolving issues detected by new check
Reviewed By: mrambacher
Differential Revision: D30823300
Pulled By: pdillinger
fbshipit-source-id: 9fff223944994c83c105e2e6496d24845dc8e572
Summary:
As a first step of supporting user-defined timestamps with ingestion, the
patch adds timestamp support to `SstFileWriter`; namely, it adds new
versions of the `Put` and `Delete` APIs that take timestamps. (`Merge`
and `DeleteRange` are currently not supported with user-defined timestamps
in general but once those features are implemented, we can handle them
in `SstFileWriter` in a similar fashion.) The new APIs validate the size of
the timestamp provided by the client. Similarly, calls to the pre-existing
timestamp-less APIs are now disallowed when user-defined timestamps are
in use according to the comparator.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8899
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D30850699
Pulled By: ltamasi
fbshipit-source-id: 779154373618f19b8f0797976bb7286783c57b67
Summary:
Context:
Some data blocks are temporarily buffered in memory in BlockBasedTableBuilder for building compression dictionary used in data block compression. Currently this memory usage is not counted toward our global memory usage utilizing block cache capacity. To improve that, this PR charges that memory usage into the block cache to achieve better memory tracking and limiting.
- Reserve memory in block cache for buffered data blocks that are used to build a compression dictionary
- Release all the memory associated with buffering the data blocks mentioned above in EnterUnbuffered(), which is called when (a) buffer limit is exceeded after buffering OR (b) the block cache becomes full after reservation OR (c) BlockBasedTableBuilder calls Finish()
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8428
Test Plan:
- Passing existing unit tests
- Passing new unit tests
Reviewed By: ajkr
Differential Revision: D30755305
Pulled By: hx235
fbshipit-source-id: 6e66665020b775154a94c4c5e0f2adaeaff13981
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:
Old typedef syntax is confusing
Most but not all changes with
perl -pi -e 's/typedef (.*) ([a-zA-Z0-9_]+);/using $2 = $1;/g' list_of_files
make format
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8751
Test Plan: existing
Reviewed By: zhichao-cao
Differential Revision: D30745277
Pulled By: pdillinger
fbshipit-source-id: 6f65f0631c3563382d43347896020413cc2366d9
Summary:
To avoid getting "Didn't get expected error from Get" from
crash test by enabling block-based filter in crash test in https://github.com/facebook/rocksdb/issues/8679.
Basically, this applies the pattern of IGNORE_STATUS_IF_ERROR in
full_filter_block.cc to block_based_filter_block.cc
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8695
Test Plan: watch for resolution of crash test runs
Reviewed By: ltamasi
Differential Revision: D30496748
Pulled By: pdillinger
fbshipit-source-id: f7808fcf14c0e787fe81da03fa8303244590d273
Summary:
I very recently realized that with https://github.com/facebook/rocksdb/issues/8669 we cannot later add
file numbers to external SST files (so that more can share db session
ids for better uniqueness properties), because of forward compatibility.
We would have a version of RocksDB that assumes session IDs are unique
on external SST files and therefore can't really break that invariant in
future files.
This change adds a table property for "orig_file_number" which is
populated by normal SST files and also external SST files generated by
SstFileWriter. SstFileWriter now keeps a db_session_id for life of the
object and increments its own file numbers for embedding in table
properties. (They are arguably "fake" file numbers because these numbers
and not embedded in the file name.)
While updating block_based_table_builder, I removed several unnecessary
fields from Rep, because following the pattern would have created
another unnecessary field.
This change also updates block_based_table_reader to use this new
property when available, which means that for newer SST files, we can
determine the stable/original <db_session_id,file_number> unique
identifier using just the file contents, not the file name. (It's a bit
complicated; detailed comments in block_based_table_reader.)
Also added DB host id to properties listing by sst_dump, which could be
useful in debugging.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8686
Test Plan: majorly overhauled StableCacheKeys test for this change
Reviewed By: zhichao-cao
Differential Revision: D30457742
Pulled By: pdillinger
fbshipit-source-id: 2e5ae7dddeb94fb9d8eac8a928486aed8b8cd445
Summary:
With expected use for a 128-bit hash, xxhash library is
upgraded to current dev (2c611a76f914828bed675f0f342d6c4199ffee1e)
as of Aug 6 so that we can use production version of XXH3_128bits
as new Hash128 function (added in hash128.h).
To make this work, however, we have to carve out the "preview" version
of XXH3 that is used in new SST Bloom and Ribbon filters, since that
will not get maintenance in xxhash releases. I have consolidated all the
relevant code into xxph3.h and made it "inline only" (no .cc file). The
working name for this hash function is changed from XXH3p to XXPH3
(XX Preview Hash) because the latter is easier to get working with no
symbol name conflicts between the headers.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8634
Test Plan:
no expected change in existing functionality. For Hash128,
added some unit tests based on those for Hash64 to ensure some basic
properties and that the values do not change accidentally.
Reviewed By: zhichao-cao
Differential Revision: D30173490
Pulled By: pdillinger
fbshipit-source-id: 06aa542a7a28b353bc2c865b9b2f8bdfe44158e4
Summary:
This is essentially resurrection and fixing of the part of
https://github.com/facebook/rocksdb/issues/8198 that was reverted in https://github.com/facebook/rocksdb/issues/8212, using data added in https://github.com/facebook/rocksdb/issues/8246. Basically,
when configuring Ribbon filter, you can specify an LSM level before which
Bloom will be used instead of Ribbon. But Bloom is only considered for
Leveled and Universal compaction styles and file going into a known LSM
level. This way, SST file writer, FIFO compaction, etc. use Ribbon filter as
you would expect with NewRibbonFilterPolicy.
So that this can be controlled with a single int value and so that flushes
can be distinguished from intra-L0, we consider flush to go to level -1 for
the purposes of this option. (Explained in API comment.)
I also expect the most common and recommended Ribbon configuration to
use Bloom during flush, to minimize slowing down writes and because according
to my estimates, Ribbon only pays off if the structure lives in memory for
more than an hour. Thus, I have changed the default for NewRibbonFilterPolicy
to be this mild hybrid configuration. I don't really want to add something like
NewHybridFilterPolicy because at least the mild hybrid configuration (Bloom for
flush, Ribbon otherwise) should be considered a natural choice.
C APIs also updated, but because they don't support overloading,
rocksdb_filterpolicy_create_ribbon is kept pure ribbon for clarity and
rocksdb_filterpolicy_create_ribbon_hybrid must be called for a hybrid
configuration. While touching C API, I changed bits per key options from
int to double.
BuiltinFilterPolicy is needed so that LevelThresholdFilterPolicy doesn't inherit
unused fields from BloomFilterPolicy.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8679
Test Plan: new + updated tests, including crash test
Reviewed By: jay-zhuang
Differential Revision: D30445797
Pulled By: pdillinger
fbshipit-source-id: 6f5aeddfd6d79f7e55493b563c2d1d2d568892e1
Summary:
MultiGet in block based table reader doesn't use BlockFetcher. As a result, the block_read_count and block_read_byte PerfContext counters were not being updated. This fixes that by updating them in MultiRead.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8676
Reviewed By: zhichao-cao
Differential Revision: D30428680
Pulled By: anand1976
fbshipit-source-id: 21846efe92588fc17123665dd06733693a40126d
Summary:
Extends https://github.com/facebook/rocksdb/issues/8659 to work for ingested external SST files, even
the same file ingested into different DBs sharing a block cache.
Note: These new cache keys are currently only enabled when FileSystem
does not provide GetUniqueId. For now, they are typically larger,
so slightly less efficient.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8669
Test Plan: Extended unit test
Reviewed By: zhichao-cao
Differential Revision: D30398532
Pulled By: pdillinger
fbshipit-source-id: 1f13e2af4b8bfff5741953a69466e9589fbc23c7
Summary:
Use DB session ids in SST table properties to make cache keys
stable across DB re-open and copy / move / restore / etc.
These new cache keys are currently only enabled when FileSystem does not
provide GetUniqueId. For now, they are typically larger, so slightly
less efficient.
Relevant to https://github.com/facebook/rocksdb/issues/7405
This change has a minor regression in PersistentCache functionality:
metaindex blocks are no longer cached in PersistentCache. Table properties
blocks already were not but ideally should be. I didn't spent effort to
fix & test these issues because we don't believe PersistentCache is used much
if at all and expect SecondaryCache to replace it. (Though PRs are welcome.)
FIXME: there is more to be fixed for stable cache keys on external SST files
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8659
Test Plan:
new unit test added, which fails when disabling new
functionality
Reviewed By: zhichao-cao
Differential Revision: D30297705
Pulled By: pdillinger
fbshipit-source-id: e8539a5c8802a79340405629870f2e3fb3822d3a
Summary:
New public interfaces:
`TraceRecord` and `TraceRecord::Handler`, available in "rocksdb/trace_record.h".
`Replayer`, available in `rocksdb/utilities/replayer.h`.
User can use `DB::NewDefaultReplayer()` to create a Replayer to auto/manual replay a trace file.
Unit tests:
- `./db_test2 --gtest_filter="DBTest2.TraceAndReplay"`: Updated with the internal API changes.
- `./db_test2 --gtest_filter="DBTest2.TraceAndManualReplay"`: New for manual replay.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8611
Reviewed By: ajkr
Differential Revision: D30266329
Pulled By: autopear
fbshipit-source-id: 1ecb3cbbedae0f6a67c18f0cc82e002b4d81b6f8
Summary:
Insert warm blocks (data, uncompressed dict, index and filter blocks) during flush in Block cache which is enabled under option BlockBasedTableOptions.prepopulate_block_cache.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8561
Test Plan: Added unit test
Reviewed By: anand1976
Differential Revision: D29773411
Pulled By: akankshamahajan15
fbshipit-source-id: 6631123c10134340ef0bd7e90baafaa6deba0e66
Summary:
This PR is for https://github.com/facebook/rocksdb/issues/8453
We need to update `s = biter.status();` when `biter.status().IsIncomplete()` is true. By doing this, can fix the problem in issue.
Besides, we still need to update `db_statistics` in `get_context.ReportCounters()` before return back.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8485
Reviewed By: jay-zhuang
Differential Revision: D29604835
Pulled By: ajkr
fbshipit-source-id: c7f2f1cd058223ce1b507ec05d57cf264b9c9710
Summary:
We ended up using a different approach for tracking the amount of
garbage in blob files (see e.g. https://github.com/facebook/rocksdb/pull/8450),
so the ability to apply only a range of table property collectors is
now unnecessary. The patch reverts this part of
https://github.com/facebook/rocksdb/pull/8298 while keeping the cleanup done
in that PR.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8465
Test Plan: `make check`
Reviewed By: jay-zhuang
Differential Revision: D29399921
Pulled By: ltamasi
fbshipit-source-id: af64816c357d0829b9d7ba8ca1477038138f6f0a
Summary:
Tsan complains due to a perceived race condition in accessing LRUHandle flags. One thread calls ```LRUHandle::SetHit()``` from ```LRUCacheShard::Lookup()```, while another thread calls ```LRUHandle::IsPending()``` from ```LRUCacheShard::IsReady()```. The latter call is from ```MultiGet```. It doesn't actually have to call ```IsReady``` since a null value indicates the cache handle is not ready, so its sufficient to check for a null value.
Also modify ```IsReady``` to acquire the LRU shard mutex.
Tests:
1. make check
2. Run tsan_crash
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8433
Reviewed By: zhichao-cao
Differential Revision: D29278030
Pulled By: anand1976
fbshipit-source-id: 0c9fed56d12eda853e72dadebe75038361bd257f
Summary:
Implement the ```WaitAll()``` interface in ```LRUCache``` to allow callers to issue multiple lookups in parallel and wait for all of them to complete. Modify ```MultiGet``` to use this to parallelize the secondary cache lookups in order to reduce the overall latency. A call to ```cache->Lookup()``` returns a handle that has an incomplete value (nullptr), and the caller can call ```cache->IsReady()``` to check whether the lookup is complete, and pass a vector of handles to ```WaitAll``` to wait for completion. If any of the lookups fail, ```MultiGet``` will read the block from the SST file.
Another change in this PR is to rename ```SecondaryCacheHandle``` to ```SecondaryCacheResultHandle``` as it more accurately describes the return result of the secondary cache lookup, which is more like a future.
Tests:
1. Add unit tests in lru_cache_test
2. Benchmark results with no secondary cache configured
Master -
```
readrandom : 41.175 micros/op 388562 ops/sec; 106.7 MB/s (7277999 of 7277999 found)
readrandom : 41.217 micros/op 388160 ops/sec; 106.6 MB/s (7274999 of 7274999 found)
multireadrandom : 10.309 micros/op 1552082 ops/sec; (28908992 of 28908992 found)
multireadrandom : 10.321 micros/op 1550218 ops/sec; (29081984 of 29081984 found)
```
This PR -
```
readrandom : 41.158 micros/op 388723 ops/sec; 106.8 MB/s (7290999 of 7290999 found)
readrandom : 41.185 micros/op 388463 ops/sec; 106.7 MB/s (7287999 of 7287999 found)
multireadrandom : 10.277 micros/op 1556801 ops/sec; (29346944 of 29346944 found)
multireadrandom : 10.253 micros/op 1560539 ops/sec; (29274944 of 29274944 found)
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8405
Reviewed By: zhichao-cao
Differential Revision: D29190509
Pulled By: anand1976
fbshipit-source-id: 6f8eff6246712af8a297cfe22ea0d1c3b2a01bb0
Summary:
This PR prepopulates warm/hot data blocks which are already in memory
into block cache at the time of flush. On a flush, the data block that is
in memory (in memtables) get flushed to the device. If using Direct IO,
additional IO is incurred to read this data back into memory again, which
is avoided by enabling newly added option.
Right now, this is enabled only for flush for data blocks. We plan to
expand this option to cover compactions in the future and for other types
of blocks.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8242
Test Plan: Add new unit test
Reviewed By: anand1976
Differential Revision: D28521703
Pulled By: akankshamahajan15
fbshipit-source-id: 7219d6958821cedce689a219c3963a6f1a9d5f05
Summary:
Marked the Ribbon filter and optimize_filters_for_memory features
as production-ready, each enabling memory savings for Bloom-like filters.
Use `NewRibbonFilterPolicy` in place of `NewBloomFilterPolicy` to use
Ribbon filters instead of Bloom, or `ribbonfilter` in place of
`bloomfilter` in configuration string.
Some small refactoring in db_stress.
Removed/refactored unused code in db_bench, in part preparing for future
default possibly being different from "disabled."
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8408
Test Plan:
Lots of prior automated, ad-hoc, and "real world" testing.
Updated tests for new API names. Quick db_bench test:
bloom fillrandom
77730 ops/sec
rocksdb.block.cache.filter.bytes.insert COUNT : 89929384
ribbon fillrandom
71492 ops/sec
rocksdb.block.cache.filter.bytes.insert COUNT : 64531384
Reviewed By: mrambacher
Differential Revision: D29140805
Pulled By: pdillinger
fbshipit-source-id: d742c922722421678f95ad85eeb0aaebc9f5e49a
Summary:
Currently, we either use the file system inode or a monotonically incrementing runtime ID as the block cache key prefix. However, if we use a monotonically incrementing runtime ID (in the case that the file system does not support inode id generation), in some cases, it cannot ensure uniqueness (e.g., we have secondary cache migrated from host to host). We use DbSessionID (20 bytes) + current file number (at most 10 bytes) as the new cache block key prefix when the secondary cache is enabled. So can accommodate scenarios such as transfer of cache state across hosts.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8360
Test Plan: add the test to lru_cache_test
Reviewed By: pdillinger
Differential Revision: D29006215
Pulled By: zhichao-cao
fbshipit-source-id: 6cff686b38d83904667a2bd39923cd030df16814
Summary:
Fix for https://github.com/facebook/rocksdb/issues/8315. Inhe lru caching test, 5100 is not enough to hold meta block and first block in some random case, increase to 6100. Fix the reference binding to null pointer, use template.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8326
Test Plan: make check
Reviewed By: pdillinger
Differential Revision: D28625666
Pulled By: zhichao-cao
fbshipit-source-id: 97b85306ae3d09bfb74addc7c65e57fe55a976a5
Summary:
With Ribbon filter work and possible variance in actual bits
per key (or prefix; general term "entry") to achieve certain FP rates,
I've received a request to be able to track actual bits per key in
generated filters. This change adds a num_filter_entries table
property, which can be combined with filter_size to get bits per key
(entry).
This can vary from num_entries in at least these ways:
* Different versions of same key are only counted once in filters.
* With prefix filters, several user keys map to the same filter entry.
* A single filter can include both prefixes and user keys.
Note that FilterBlockBuilder::NumAdded() didn't do anything useful
except distinguish empty from non-empty.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8323
Test Plan: basic unit test included, others updated
Reviewed By: jay-zhuang
Differential Revision: D28596210
Pulled By: pdillinger
fbshipit-source-id: 529a111f3c84501e5a470bc84705e436ee68c376
Summary:
This change gathers and publishes statistics about the
kinds of items in block cache. This is especially important for
profiling relative usage of cache by index vs. filter vs. data blocks.
It works by iterating over the cache during periodic stats dump
(InternalStats, stats_dump_period_sec) or on demand when
DB::Get(Map)Property(kBlockCacheEntryStats), except that for
efficiency and sharing among column families, saved data from
the last scan is used when the data is not considered too old.
The new information can be seen in info LOG, for example:
Block cache LRUCache@0x7fca62229330 capacity: 95.37 MB collections: 8 last_copies: 0 last_secs: 0.00178 secs_since: 0
Block cache entry stats(count,size,portion): DataBlock(7092,28.24 MB,29.6136%) FilterBlock(215,867.90 KB,0.888728%) FilterMetaBlock(2,5.31 KB,0.00544%) IndexBlock(217,180.11 KB,0.184432%) WriteBuffer(1,256.00 KB,0.262144%) Misc(1,0.00 KB,0%)
And also through DB::GetProperty and GetMapProperty (here using
ldb just for demonstration):
$ ./ldb --db=/dev/shm/dbbench/ get_property rocksdb.block-cache-entry-stats
rocksdb.block-cache-entry-stats.bytes.data-block: 0
rocksdb.block-cache-entry-stats.bytes.deprecated-filter-block: 0
rocksdb.block-cache-entry-stats.bytes.filter-block: 0
rocksdb.block-cache-entry-stats.bytes.filter-meta-block: 0
rocksdb.block-cache-entry-stats.bytes.index-block: 178992
rocksdb.block-cache-entry-stats.bytes.misc: 0
rocksdb.block-cache-entry-stats.bytes.other-block: 0
rocksdb.block-cache-entry-stats.bytes.write-buffer: 0
rocksdb.block-cache-entry-stats.capacity: 8388608
rocksdb.block-cache-entry-stats.count.data-block: 0
rocksdb.block-cache-entry-stats.count.deprecated-filter-block: 0
rocksdb.block-cache-entry-stats.count.filter-block: 0
rocksdb.block-cache-entry-stats.count.filter-meta-block: 0
rocksdb.block-cache-entry-stats.count.index-block: 215
rocksdb.block-cache-entry-stats.count.misc: 1
rocksdb.block-cache-entry-stats.count.other-block: 0
rocksdb.block-cache-entry-stats.count.write-buffer: 0
rocksdb.block-cache-entry-stats.id: LRUCache@0x7f3636661290
rocksdb.block-cache-entry-stats.percent.data-block: 0.000000
rocksdb.block-cache-entry-stats.percent.deprecated-filter-block: 0.000000
rocksdb.block-cache-entry-stats.percent.filter-block: 0.000000
rocksdb.block-cache-entry-stats.percent.filter-meta-block: 0.000000
rocksdb.block-cache-entry-stats.percent.index-block: 2.133751
rocksdb.block-cache-entry-stats.percent.misc: 0.000000
rocksdb.block-cache-entry-stats.percent.other-block: 0.000000
rocksdb.block-cache-entry-stats.percent.write-buffer: 0.000000
rocksdb.block-cache-entry-stats.secs_for_last_collection: 0.000052
rocksdb.block-cache-entry-stats.secs_since_last_collection: 0
Solution detail - We need some way to flag what kind of blocks each
entry belongs to, preferably without changing the Cache API.
One of the complications is that Cache is a general interface that could
have other users that don't adhere to whichever convention we decide
on for keys and values. Or we would pay for an extra field in the Handle
that would only be used for this purpose.
This change uses a back-door approach, the deleter, to indicate the
"role" of a Cache entry (in addition to the value type, implicitly).
This has the added benefit of ensuring proper code origin whenever we
recognize a particular role for a cache entry; if the entry came from
some other part of the code, it will use an unrecognized deleter, which
we simply attribute to the "Misc" role.
An internal API makes for simple instantiation and automatic
registration of Cache deleters for a given value type and "role".
Another internal API, CacheEntryStatsCollector, solves the problem of
caching the results of a scan and sharing them, to ensure scans are
neither excessive nor redundant so as not to harm Cache performance.
Because code is added to BlocklikeTraits, it is pulled out of
block_based_table_reader.cc into its own file.
This is a reformulation of https://github.com/facebook/rocksdb/issues/8276, without the type checking option
(could still be added), and with actual stat gathering.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8297
Test Plan: manual testing with db_bench, and a couple of basic unit tests
Reviewed By: ltamasi
Differential Revision: D28488721
Pulled By: pdillinger
fbshipit-source-id: 472f524a9691b5afb107934be2d41d84f2b129fb
Summary:
This patch does two things:
1) Introduces some aliases in order to eliminate/prevent long-winded type names
w/r/t the internal table property collectors (see e.g.
`std::vector<std::unique_ptr<IntTblPropCollectorFactory>>`).
2) Makes it possible to apply only a subrange of table property collectors during
table building by turning `TableBuilderOptions::int_tbl_prop_collector_factories`
from a pointer to a `vector` into a range (i.e. a pair of iterators).
Rationale: I plan to introduce a BlobDB related table property collector, which
should only be applied during table creation if blob storage is enabled at the moment
(which can be changed dynamically). This change will make it possible to include/
exclude the BlobDB related collector as needed without having to introduce
a second `vector` of collectors in `ColumnFamilyData` with pretty much the same
contents.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8298
Test Plan: `make check`
Reviewed By: jay-zhuang
Differential Revision: D28430910
Pulled By: ltamasi
fbshipit-source-id: a81d28f2c59495865300f43deb2257d2e6977c8e
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:
Add `num_levels`, `is_bottommost`, and table file creation
`reason` to `FilterBuildingContext`, in anticipation of more powerful
Bloom-like filter support.
To support this, added `is_bottommost` and `reason` to
`TableBuilderOptions`, which allowed removing `reason` parameter from
`rocksdb::BuildTable`.
I attempted to remove `skip_filters` from `TableBuilderOptions`, because
filter construction decisions should arise from options, not one-off
parameters. I could not completely remove it because the public API for
SstFileWriter takes a `skip_filters` parameter, and translating this
into an option change would mean awkwardly replacing the table_factory
if it is BlockBasedTableFactory with new filter_policy=nullptr option.
I marked this public skip_filters option as deprecated because of this
oddity. (skip_filters on the read side probably makes sense.)
At least `skip_filters` is now largely hidden for users of
`TableBuilderOptions` and is no longer used for implementing the
optimize_filters_for_hits option. Bringing the logic for that option
closer to handling of FilterBuildingContext makes it more obvious that
hese two are using the same notion of "bottommost." (Planned:
configuration options for Bloom-like filters that generalize
`optimize_filters_for_hits`)
Recommended follow-up: Try to get away from "bottommost level" naming of
things, which is inaccurate (see
VersionStorageInfo::RangeMightExistAfterSortedRun), and move to
"bottommost run" or just "bottommost."
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8246
Test Plan:
extended an existing unit test to exercise and check various
filter building contexts. Also, existing tests for
optimize_filters_for_hits validate some of the "bottommost" handling,
which is now closely connected to FilterBuildingContext::is_bottommost
through TableBuilderOptions::is_bottommost
Reviewed By: mrambacher
Differential Revision: D28099346
Pulled By: pdillinger
fbshipit-source-id: 2c1072e29c24d4ac404c761a7b7663292372600a
Summary:
Greatly reduced the not-quite-copy-paste giant parameter lists
of rocksdb::NewTableBuilder, rocksdb::BuildTable,
BlockBasedTableBuilder::Rep ctor, and BlockBasedTableBuilder ctor.
Moved weird separate parameter `uint32_t column_family_id` of
TableFactory::NewTableBuilder into TableBuilderOptions.
Re-ordered parameters to TableBuilderOptions ctor, so that `uint64_t
target_file_size` is not randomly placed between uint64_t timestamps
(was easy to mix up).
Replaced a couple of fields of BlockBasedTableBuilder::Rep with a
FilterBuildingContext. The motivation for this change is making it
easier to pass along more data into new fields in FilterBuildingContext
(follow-up PR).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8240
Test Plan: ASAN make check
Reviewed By: mrambacher
Differential Revision: D28075891
Pulled By: pdillinger
fbshipit-source-id: fddb3dbb8260a0e8bdcbb51b877ebabf9a690d4f
Summary:
BlockPrefetcher is used by iterators to prefetch data if they
anticipate more data to be used in future and this is valid for forward sequential
scans. But BlockPrefetcher tracks only num_file_reads_ and not if reads
are sequential. This presents problem for MultiGet with large number of
keys when it reseeks index iterator and data block. FilePrefetchBuffer
can end up doing large readahead for reseeks as readahead size
increases exponentially once readahead is enabled. Same issue is with
BlockBasedTableIterator.
Add previous length and offset read as well in BlockPrefetcher (creates
FilePrefetchBuffer) and FilePrefetchBuffer (does prefetching of data) to
determine if reads are sequential and then prefetch.
Update the last block read after cache hit to take reads from cache also
in account.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7394
Test Plan: Add new unit test case
Reviewed By: anand1976
Differential Revision: D23737617
Pulled By: akankshamahajan15
fbshipit-source-id: 8e6917c25ed87b285ee495d1b68dc623d71205a3
Summary:
Renaming ImmutableCFOptions::info_log and statistics to logger and stats. This is stage 2 in creating an ImmutableOptions class. It is necessary because the names match those in ImmutableOptions and have different types.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8227
Reviewed By: jay-zhuang
Differential Revision: D28000967
Pulled By: mrambacher
fbshipit-source-id: 3bf2aa04e8f1e8724d825b7deacf41080c14420b
Summary:
As previously coded, a Configurable extension would need access to code not in the public API. This change moves RegisterOptions into the Configurable class and therefore available to public extensions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8223
Reviewed By: anand1976
Differential Revision: D27960188
Pulled By: mrambacher
fbshipit-source-id: ac88b19397183df633902def5b5701b9b65fbf40
Summary:
The block_based_table_builder buffers some blocks in memory to construct a good compression dictionary. Before this commit, the keys from each block were buffered separately for convenience. However, the buffered block data implicitly contains all keys. This commit eliminates the redundant key buffers and reduces memory usage.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8219
Reviewed By: ajkr
Differential Revision: D27945851
Pulled By: saketh-are
fbshipit-source-id: caf3cac1217201e080a1e24b542bedf20973afee
Summary:
This partially reverts commit 10196d7edc.
The problem with this change is because of important filter use cases:
FIFO compaction and SST writer. FIFO "compaction" always uses level 0 so
would only use Ribbon filters if specifically including level 0 for the
Ribbon filter policy. SST writer sets level_at_creation=-1 to indicate
unknown level, and this would be treated the same as level 0 unless
fixed.
We are keeping the part about committing to permanent schema, which is
only changes to API comments and HISTORY.md.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8212
Test Plan: CI
Reviewed By: jay-zhuang
Differential Revision: D27896468
Pulled By: pdillinger
fbshipit-source-id: 50a775f7cba5d64fb729d9b982e355864020596e
Summary:
Since the Ribbon filter schema seems good (compatible back to
6.15.0), this change commits to long term support of the SST schema,
even though we expect the API for enabling Ribbon to change (still
called NewExperimentalRibbonFilterPolicy).
This also adds support for "hybrid" configuration in which some levels
use Bloom (higher levels, lower numbered) for speed and the rest use
Ribbon (lower levels, higher numbered) for memory space efficiency.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8198
Test Plan: unit test added, crash test support
Reviewed By: jay-zhuang
Differential Revision: D27831232
Pulled By: pdillinger
fbshipit-source-id: 90e528677689474d293ed6710b42ba89fbd5b5ab
Summary:
According to https://github.com/facebook/rocksdb/issues/5907, each filter partition "should include the bloom of the prefix of the last
key in the previous partition" so that SeekForPrev() in prefix mode can return correct result.
The prefix of the last key in the previous partition does not necessarily have the same prefix
as the first key in the current partition. Regardless of the first key in current partition, the
prefix of the last key in the previous partition should be added. The existing code, however,
does not follow this. Furthermore, there is another issue: when finishing current filter partition,
`FullFilterBlockBuilder::AddPrefix()` is called for the first key in next filter partition, which effectively
overwrites `last_prefix_str_` prematurely. Consequently, when the filter block builder proceeds
to the next partition, `last_prefix_str_` will be the prefix of its first key, leaving no way of adding
the bloom of the prefix of the last key of the previous partition.
Prefix extractor is FixedLength.2.
```
[ filter part 1 ] [ filter part 2 ]
abc d
```
When SeekForPrev("abcd"), checking the filter partition will land on filter part 2 because "abcd" > "abc"
but smaller than "d".
If the filter in filter part 2 happens to return false for the test for "ab", then SeekForPrev("abcd") will build
incorrect iterator tree in non-total-order mode.
Also fix a unit test which starts to fail following this PR. `InDomain` should not fail due to assertion
error when checking on an arbitrary key.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8137
Test Plan:
```
make check
```
Without this fix, the following command will fail pretty soon.
```
./db_stress --acquire_snapshot_one_in=10000 --avoid_flush_during_recovery=0 \
--avoid_unnecessary_blocking_io=0 --backup_max_size=104857600 --backup_one_in=0 \
--batch_protection_bytes_per_key=0 --block_size=16384 --bloom_bits=17 \
--bottommost_compression_type=disable --cache_index_and_filter_blocks=1 --cache_size=1048576 \
--checkpoint_one_in=0 --checksum_type=kxxHash64 --clear_column_family_one_in=0 \
--compact_files_one_in=1000000 --compact_range_one_in=1000000 --compaction_ttl=0 \
--compression_max_dict_buffer_bytes=0 --compression_max_dict_bytes=0 \
--compression_parallel_threads=1 --compression_type=zstd --compression_zstd_max_train_bytes=0 \
--continuous_verification_interval=0 --db=/dev/shm/rocksdb/rocksdb_crashtest_whitebox \
--db_write_buffer_size=8388608 --delpercent=5 --delrangepercent=0 --destroy_db_initially=0 --enable_blob_files=0 \
--enable_compaction_filter=0 --enable_pipelined_write=1 --file_checksum_impl=big --flush_one_in=1000000 \
--format_version=5 --get_current_wal_file_one_in=0 --get_live_files_one_in=1000000 --get_property_one_in=1000000 \
--get_sorted_wal_files_one_in=0 --index_block_restart_interval=4 --index_type=2 --ingest_external_file_one_in=0 \
--iterpercent=10 --key_len_percent_dist=1,30,69 --level_compaction_dynamic_level_bytes=True \
--log2_keys_per_lock=10 --long_running_snapshots=1 --mark_for_compaction_one_file_in=0 \
--max_background_compactions=20 --max_bytes_for_level_base=10485760 --max_key=100000000 --max_key_len=3 \
--max_manifest_file_size=1073741824 --max_write_batch_group_size_bytes=16777216 --max_write_buffer_number=3 \
--max_write_buffer_size_to_maintain=8388608 --memtablerep=skip_list --mmap_read=1 --mock_direct_io=False \
--nooverwritepercent=0 --open_files=500000 --ops_per_thread=20000000 --optimize_filters_for_memory=0 --paranoid_file_checks=1 --partition_filters=1 --partition_pinning=0 --pause_background_one_in=1000000 \
--periodic_compaction_seconds=0 --prefixpercent=5 --progress_reports=0 --read_fault_one_in=0 --read_only=0 \
--readpercent=45 --recycle_log_file_num=0 --reopen=20 --secondary_catch_up_one_in=0 \
--snapshot_hold_ops=100000 --sst_file_manager_bytes_per_sec=104857600 \
--sst_file_manager_bytes_per_truncate=0 --subcompactions=2 --sync=0 --sync_fault_injection=False \
--target_file_size_base=2097152 --target_file_size_multiplier=2 --test_batches_snapshots=0 --test_cf_consistency=0 \
--top_level_index_pinning=0 --unpartitioned_pinning=1 --use_blob_db=0 --use_block_based_filter=0 \
--use_direct_io_for_flush_and_compaction=0 --use_direct_reads=0 --use_full_merge_v1=0 --use_merge=0 \
--use_multiget=0 --use_ribbon_filter=0 --use_txn=0 --user_timestamp_size=8 --verify_checksum=1 \
--verify_checksum_one_in=1000000 --verify_db_one_in=100000 --write_buffer_size=4194304 \
--write_dbid_to_manifest=1 --writepercent=35
```
Reviewed By: pdillinger
Differential Revision: D27553054
Pulled By: riversand963
fbshipit-source-id: 60e391e4a2d8d98a9a3172ec5d6176b90ec3de98
