Commit Graph

328 Commits

Author SHA1 Message Date
Akanksha Mahajan
17ce1ca48b Reuse internal auto readhead_size at each Level (expect L0) for Iterations (#9056)
Summary:
RocksDB does auto-readahead for iterators on noticing more than two sequential reads for a table file if user doesn't provide readahead_size. The readahead starts at 8KB and doubles on every additional read up to max_auto_readahead_size. However at each level, if iterator moves over next file, readahead_size starts again from 8KB.

This PR introduces a new ReadOption "adaptive_readahead" which when set true will maintain readahead_size  at each level. So when iterator moves from one file to another, new file's readahead_size will continue from previous file's readahead_size instead of scratch. However if reads are not sequential it will fall back to 8KB (default) with no prefetching for that block.

1. If block is found in cache but it was eligible for prefetch (block wasn't in Rocksdb's prefetch buffer),  readahead_size will decrease by 8KB.
2. It maintains readahead_size for L1 - Ln levels.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9056

Test Plan:
Added new unit tests
Ran db_bench for "readseq, seekrandom, seekrandomwhilewriting, readrandom" with --adaptive_readahead=true and there was no regression if new feature is enabled.

Reviewed By: anand1976

Differential Revision: D31773640

Pulled By: akankshamahajan15

fbshipit-source-id: 7332d16258b846ae5cea773009195a5af58f8f98
2021-11-10 16:20:04 -08:00
Hui Xiao
3018a3e27e Minor improvement to CacheReservationManager/WriteBufferManager/CompressionDictBuilding (#9139)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/9139

Reviewed By: zhichao-cao

Differential Revision: D32211415

Pulled By: hx235

fbshipit-source-id: 39ce036ba34e1fb4a1992a33ac6904a4a943301d
2021-11-05 16:13:47 -07:00
Hui Xiao
1ababeb76a Deallocate payload of BlockBasedTableBuilder::Rep::FilterBlockBuilder earlier for Full/PartitionedFilter (#9070)
Summary:
Note: This PR is the 1st part of a bigger PR stack (https://github.com/facebook/rocksdb/pull/9073).

Context:
Previously, the payload (i.e, filter data) within `BlockBasedTableBuilder::Rep::FilterBlockBuilder` object is not deallocated until `BlockBasedTableBuilder` is deallocated, despite it is no longer useful after its related `filter_content` being written.
- Transferred the payload (i.e, the filter data) out of `BlockBasedTableBuilder::Rep::FilterBlockBuilder` object
- For PartitionedFilter:
   - Unified `filters` and `filter_gc` lists into one `std::deque<FilterEntry> filters` by adding a new field `last_filter_entry_key` and storing the `std::unique_ptr filter_data` with the `Slice filter` in the same entry
   - Reset `last_filter_data` in the case where `filters` is empty, which should be as by then we would've finish using all the `Slice filter`
- Deallocated the payload by going out of scope as soon as we're done with using the `filter_content` associated with the payload
- This is an internal interface change at the level of `FilterBlockBuilder::Finish()`, which leads to touching the inherited interface in `BlockBasedFilterBlockBuilder`. But for that, the payload transferring is ignored.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9070

Test Plan: - The main focus is to catch segment fault error during `FilterBlockBuilder::Finish()` and `BlockBasedTableBuilder::Finish()` and interface mismatch. Relying on existing CI tests is enough as `assert(false)` was temporarily added to verify the new logic of transferring ownership indeed run

Reviewed By: pdillinger

Differential Revision: D31884933

Pulled By: hx235

fbshipit-source-id: f73ecfbea13788d4fc058013ace27230110b52f4
2021-11-04 13:35:38 -07:00
Peter Dillinger
dfedc74d82 Some checksum code refactoring (#9113)
Summary:
To prepare for adding checksum to footer and "context aware"
checksums. This also brings closely related code much closer together.

Recently added `BlockBasedTableBuilder::ComputeBlockTrailer` for testing
is made obsolete in the refactoring, as testing the checksums can happen
at a lower level of abstraction.

Also now checking for unrecognized checksum type on reading footer,
rather than later on use.

Also removed an obsolete function delcaration.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9113

Test Plan:
existing tests worked before refactoring to remove
`ComputeBlockTrailer`. And then refactored+improved tests using it.

Reviewed By: mrambacher

Differential Revision: D32090149

Pulled By: pdillinger

fbshipit-source-id: 2879da683c1498ea85a3b70dace9b6d9f6b47b6e
2021-11-04 09:09:34 -07:00
hx235
a5ec5e3ea0 Minor improvement to #8428 (Account for dictionary-building buffer in global memory limit) (#9032)
Summary:
Summary/Context:
- Renamed `cache_rev_mng` to `compression_dict_buffer_cache_res_mgr`
   - It is to distinguish with other potential `cache_res_mgr` in `BlockBasedTableBuilder` and to use correct short-hand for the words "reservation", "manager"
- Added `table_options.block_cache == nullptr` in additional to `table_options.no_block_cache == true` to be conditions where we don't create a `CacheReservationManager`
   - Theoretically `table_options.no_block_cache == true` is equivalent to `table_options.block_cache == nullptr` by API. But since segment fault will be generated by passing `nullptr` into `CacheReservationManager`'s constructor, it does not hurt to directly verify  `table_options.block_cache != nullptr` before passing in
- Renamed `is_cache_full` to `exceeds_global_block_cache_limit`
   - It is to hide implementation detail of cache reservation and to emphasize on the concept/design intent of caping memory within global block cache limit

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9032

Test Plan: - Passing existing tests

Reviewed By: ajkr

Differential Revision: D32005807

Pulled By: hx235

fbshipit-source-id: 619fd17bb924199de3db5924d8ab7dae53b1efa2
2021-11-01 14:28:09 -07:00
Peter Dillinger
a7d4bea43a Implement XXH3 block checksum type (#9069)
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
2021-10-28 22:15:17 -07:00
Peter Dillinger
5bf9a7d5ee Clarify caching behavior for index and filter partitions (#9068)
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
2021-10-27 17:23:04 -07:00
Zhichao Cao
6d93b87588 Add lowest_used_cache_tier to ImmutableDBOptions to enable or disable Secondary Cache (#9050)
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
2021-10-19 15:54:23 -07:00
Peter Dillinger
b234a3f569 Improve data block construction performance (#9040)
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
2021-10-19 12:36:21 -07:00
Peter Dillinger
9d66d6d13e Two performance improvements in BlockBuilder (#9039)
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
2021-10-18 08:35:38 -07:00
mrambacher
13ae16c315 Cleanup includes in dbformat.h (#8930)
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
2021-09-29 04:04:40 -07:00
Hui Xiao
d6bd1a0291 Support "level_at_creation" in TablePropertiesCollectorFactory::Context (#8919)
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
2021-09-28 12:35:24 -07:00
mrambacher
e0f697d2bd Make SliceTransform into a Customizable class (#8641)
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
2021-09-27 07:43:47 -07:00
Peter Dillinger
2819c7840e Fix PrepopulateBlockCache::kFlushOnly (#8750)
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
2021-09-15 15:33:20 -07:00
anand76
7743f033b1 More robust checking of IO uring completion data (#8894)
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
2021-09-15 12:44:43 -07:00
Peter Dillinger
bda8d93ba9 Fix and detect headers with missing dependencies (#8893)
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
2021-09-10 10:00:26 -07:00
Levi Tamasi
7e78d7c540 Support timestamps in SstFileWriter (#8899)
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
2021-09-09 18:58:01 -07:00
Hui Xiao
91b95cadee Account for dictionary-building buffer in global memory limit (#8428)
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
2021-09-08 12:35:46 -07:00
Peter Dillinger
cb5b851ff8 Add (& fix) some simple source code checks (#8821)
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
2021-09-07 21:19:27 -07:00
Peter Dillinger
4750421ece Replace most typedef with using= (#8751)
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
2021-09-07 11:31:59 -07:00
Peter Dillinger
1a5eb33d91 Allow intentionally swallowed errors in BlockBasedFilterBlockReader (#8695)
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
2021-08-23 15:50:27 -07:00
Peter Dillinger
04db764831 Embed original file number in SST table properties (#8686)
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
2021-08-20 20:40:48 -07:00
Peter Dillinger
22161b7547 Upgrade xxhash, add Hash128 (#8634)
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
2021-08-20 18:41:51 -07:00
Peter Dillinger
2a383f21f4 Add Bloom/Ribbon hybrid API support (#8679)
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
2021-08-20 18:00:16 -07:00
anand76
22f2936b35 Update the block_read_count/block_read_byte counters in MultiGet (#8676)
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
2021-08-20 11:50:42 -07:00
Peter Dillinger
b6269b078a Stable cache keys on ingested SST files (#8669)
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
2021-08-18 11:33:03 -07:00
Peter Dillinger
a207c27809 Stable cache keys using DB session ids in SSTs (#8659)
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
2021-08-16 20:37:20 -07:00
Merlin Mao
f58d276764 Make TraceRecord and Replayer public (#8611)
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
2021-08-11 19:32:46 -07:00
Akanksha Mahajan
fd2079938d Dynamically configure BlockBasedTableOptions.prepopulate_block_cache (#8620)
Summary:
Dynamically configure BlockBasedTableOptions.prepopulate_block_cache using DB::SetOptions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8620

Test Plan: Added new unit test

Reviewed By: anand1976

Differential Revision: D30091319

Pulled By: akankshamahajan15

fbshipit-source-id: fb586d1848a8dd525bba7b2f9eeac34f2fc6d82c
2021-08-05 19:44:51 -07:00
Akanksha Mahajan
a074d46a5a Fix clang failure (#8621)
Summary:
Fixed clang failure because of memory leak

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8621

Test Plan: CircleCI clang job

Reviewed By: pdillinger

Differential Revision: D30114337

Pulled By: akankshamahajan15

fbshipit-source-id: 16572b9bcbaa053c2ab7bc1c344148d0e6f8039c
2021-08-04 17:12:58 -07:00
Akanksha Mahajan
8b2f60b668 Cache warming blocks during flush (#8561)
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
2021-08-03 12:44:15 -07:00
hongrubb
870033291a Fix Get() return status when block cache is disabled (#8485)
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
2021-07-13 18:13:24 -07:00
mrambacher
c8665611bc Make FlushBlockPolicyFactory into a Customizable class (#8432)
Summary:
Add ability to treat FlushBlockPolicyFactory as a Customizable.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8432

Reviewed By: zhichao-cao

Differential Revision: D29558941

Pulled By: mrambacher

fbshipit-source-id: 4a791af941ea4a65fc2f1fdfb1d7a95f42ca6774
2021-07-12 09:04:59 -07:00
Levi Tamasi
1ae026c400 Partially revert the "apply subrange of table property collectors" change (#8465)
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
2021-07-06 10:14:32 -07:00
anand76
a50da404be Fix a tsan warning due to reading flags in LRUHandle without holding a mutex (#8433)
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
2021-06-21 21:23:56 -07:00
anand76
8ea0a2c1bd Parallelize secondary cache lookup in MultiGet (#8405)
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
2021-06-18 09:35:59 -07:00
Akanksha Mahajan
5ba1b6e549 Cache warming data blocks during flush (#8242)
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
2021-06-17 21:56:47 -07:00
Peter Dillinger
865a25101d Mark Ribbon filter and optimize_filters_for_memory as production (#8408)
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
2021-06-17 12:29:16 -07:00
Zhichao Cao
f44e69c64a Use DbSessionId as cache key prefix when secondary cache is enabled (#8360)
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
2021-06-10 11:02:43 -07:00
Zhichao Cao
a4405fd981 fix lru caching test and fix reference binding to null pointer (#8326)
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
2021-05-24 08:37:00 -07:00
Zhichao Cao
7303d02bdf Use new Insert and Lookup APIs in table reader to support secondary cache (#8315)
Summary:
Secondary cache is implemented to achieve the secondary cache tier for block cache. New Insert and Lookup APIs are introduced in https://github.com/facebook/rocksdb/issues/8271  . To support and use the secondary cache in block based table reader, this PR introduces the corresponding callback functions that will be used in secondary cache, and update the Insert and Lookup APIs accordingly.

benchmarking:
./db_bench --benchmarks="fillrandom" -num=1000000 -key_size=32 -value_size=256 -use_direct_io_for_flush_and_compaction=true -db=/tmp/rocks_t/db -partition_index_and_filters=true

./db_bench -db=/tmp/rocks_t/db -use_existing_db=true -benchmarks=readrandom -num=1000000 -key_size=32 -value_size=256 -use_direct_reads=true -cache_size=1073741824 -cache_numshardbits=5 -cache_index_and_filter_blocks=true -read_random_exp_range=17 -statistics -partition_index_and_filters=true -stats_dump_period_sec=30 -reads=50000000

master benchmarking results:
readrandom   :       3.923 micros/op 254881 ops/sec;   33.4 MB/s (23849796 of 50000000 found)
rocksdb.db.get.micros P50 : 2.820992 P95 : 5.636716 P99 : 16.450553 P100 : 8396.000000 COUNT : 50000000 SUM : 179947064

Current PR benchmarking results
readrandom   :       4.083 micros/op 244925 ops/sec;   32.1 MB/s (23849796 of 50000000 found)
rocksdb.db.get.micros P50 : 2.967687 P95 : 5.754916 P99 : 15.665912 P100 : 8213.000000 COUNT : 50000000 SUM : 187250053

About 3.8% throughput reduction.
P50: 5.2% increasing, P95, 2.09% increasing, P99 4.77% improvement

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8315

Test Plan: added the testing case

Reviewed By: anand1976

Differential Revision: D28599774

Pulled By: zhichao-cao

fbshipit-source-id: 098c4df0d7327d3a546df7604b2f1602f13044ed
2021-05-21 18:29:12 -07:00
Peter Dillinger
3469d60fcc Add table properties for number of entries added to filters (#8323)
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
2021-05-21 17:11:32 -07:00
Peter Dillinger
311a544c2a Use deleters to label cache entries and collect stats (#8297)
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
2021-05-19 16:51:13 -07:00
Levi Tamasi
d83542ca83 Make it possible to apply only a subrange of table property collectors (#8298)
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
2021-05-17 18:28:39 -07:00
Jay Zhuang
d15fbae449 Refactor Option obj address from char* to void* (#8295)
Summary:
And replace `reinterpret_cast` with `static_cast` or no cast.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8295

Test Plan: `make check`

Reviewed By: mrambacher

Differential Revision: D28420303

Pulled By: jay-zhuang

fbshipit-source-id: 645be123a0df624dc2bea37cd54a35403fc494fa
2021-05-13 14:29:42 -07:00
mrambacher
8948dc8524 Make ImmutableOptions struct that inherits from ImmutableCFOptions and ImmutableDBOptions (#8262)
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
2021-05-05 14:00:17 -07:00
Peter Dillinger
d2ca04e3ed Add more LSM info to FilterBuildingContext (#8246)
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
2021-04-30 13:50:13 -07:00
Peter Dillinger
85becd94c1 Refactor: use TableBuilderOptions to reduce parameter lists (#8240)
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
2021-04-29 07:00:50 -07:00
Akanksha Mahajan
a0e0feca62 Improve BlockPrefetcher to prefetch only for sequential scans (#7394)
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
2021-04-28 12:53:46 -07:00
mrambacher
0ca6d6297f Rename variables in ImmutableCFOptions to avoid conflicts with ImmutableDBOptions (#8227)
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
2021-04-26 12:43:45 -07:00
mrambacher
6bab3a34e9 Move RegisterOptions into the Configurable API (#8223)
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
2021-04-26 03:13:24 -07:00
Saketh Are
cc1c3ee54e Eliminate double-buffering of keys in block_based_table_builder (#8219)
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
2021-04-23 12:45:02 -07:00
Peter Dillinger
95f6add746 Revert Ribbon starting level support from #8198 (#8212)
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
2021-04-20 19:46:40 -07:00
Peter Dillinger
10196d7edc Ribbon long-term support, starting level support (#8198)
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
2021-04-16 15:43:08 -07:00
Yanqin Jin
09528f9fa1 Fix a bug for SeekForPrev with partitioned filter and prefix (#8137)
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
2021-04-06 12:14:08 -07:00
Andrew Kryczka
c43a37a922 Fix compression dictionary sampling with dedicated range tombstone SSTs (#8141)
Summary:
Return early in case there are zero data blocks when
`BlockBasedTableBuilder::EnterUnbuffered()` is called. This crash can
only be triggered by applying dictionary compression to SST files that
contain only range tombstones. It cannot be triggered by a low buffer
limit alone since we only consider entering unbuffered mode after
buffering a data block causing the limit to be breached, or `Finish()`ing the file. It also cannot
be triggered by a totally empty file because those go through
`Abandon()` rather than `Finish()` so unbuffered mode is never entered.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8141

Test Plan: added a unit test that repro'd the "Floating point exception"

Reviewed By: riversand963

Differential Revision: D27495640

Pulled By: ajkr

fbshipit-source-id: a463cfba476919dc5c5c380800a75a86c31ffa23
2021-04-01 05:08:17 -07:00
Andrew Kryczka
1ba2b8a568 Add sample_for_compression results to table properties (#8139)
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
2021-03-31 18:21:50 -07:00
Andrew Kryczka
c20a7cd6c7 Apply sample_for_compression to all block-based tables (#8105)
Summary:
Previously it only applied to block-based tables generated by flush. This restriction
was undocumented and blocked a new use case. Now compression sampling
applies to all block-based tables we generate when it is enabled.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8105

Test Plan: new unit test

Reviewed By: riversand963

Differential Revision: D27317275

Pulled By: ajkr

fbshipit-source-id: cd9fcc5178d6515e8cb59c6facb5ac01893cb5b0
2021-03-25 15:00:45 -07:00
Yanqin Jin
0304352882 Fix a bug in key comparison when index type is kBinarySearchWithFirstKey (#8062)
Summary:
When timestamp is enabled, key comparison should take this into account.
In `BlockBasedTableReader::Get()`, `BlockBasedTableReader::MultiGet()`,
assume the target key is `key`, and the timestamp upper bound is `ts`.
The highest key in current block is (key, ts1), while the lowest key in next
block is (key, ts2).
If
```
ts1 > ts > ts2
```
then
```
(key, ts1) < (key, ts) < (key, ts2)
```
It can be shown that if `Compare()` is used, then we will mistakenly skip the next
block. Instead, we should use `CompareWithoutTimestamp()`.

The majority of this PR makes some existing tests in `db_with_timestamp_basic_test.cc`
parameterized so that different index types can be tested. A new unit test is
also added for more coverage.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8062

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D27057557

Pulled By: riversand963

fbshipit-source-id: c1062fa7c159ed600a1ad7e461531d52265021f1
2021-03-15 17:44:52 -07:00
mrambacher
3dff28cf9b Use SystemClock* instead of std::shared_ptr<SystemClock> in lower level routines (#8033)
Summary:
For performance purposes, the lower level routines were changed to use a SystemClock* instead of a std::shared_ptr<SystemClock>.  The shared ptr has some performance degradation on certain hardware classes.

For most of the system, there is no risk of the pointer being deleted/invalid because the shared_ptr will be stored elsewhere.  For example, the ImmutableDBOptions stores the Env which has a std::shared_ptr<SystemClock> in it.  The SystemClock* within the ImmutableDBOptions is essentially a "short cut" to gain access to this constant resource.

There were a few classes (PeriodicWorkScheduler?) where the "short cut" property did not hold.  In those cases, the shared pointer was preserved.

Using db_bench readrandom perf_level=3 on my EC2 box, this change performed as well or better than 6.17:

6.17: readrandom   :      28.046 micros/op 854902 ops/sec;   61.3 MB/s (355999 of 355999 found)
6.18: readrandom   :      32.615 micros/op 735306 ops/sec;   52.7 MB/s (290999 of 290999 found)
PR: readrandom   :      27.500 micros/op 871909 ops/sec;   62.5 MB/s (367999 of 367999 found)

(Note that the times for 6.18 are prior to revert of the SystemClock).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8033

Reviewed By: pdillinger

Differential Revision: D27014563

Pulled By: mrambacher

fbshipit-source-id: ad0459eba03182e454391b5926bf5cdd45657b67
2021-03-15 04:34:11 -07:00
Peter Dillinger
a8b3b9a20c Refine Ribbon configuration, improve testing, add Homogeneous (#7879)
Summary:
This change only affects non-schema-critical aspects of the production candidate Ribbon filter. Specifically, it refines choice of internal configuration parameters based on inputs. The changes are minor enough that the schema tests in bloom_test, some of which depend on this, are unaffected. There are also some minor optimizations and refactorings.

This would be a schema change for "smash" Ribbon, to fix some known issues with small filters, but "smash" Ribbon is not accessible in public APIs. Unit test CompactnessAndBacktrackAndFpRate updated to test small and medium-large filters. Run with --thoroughness=100 or so for much better detection power (not appropriate for continuous regression testing).

Homogenous Ribbon:
This change adds internally a Ribbon filter variant we call Homogeneous Ribbon, in collaboration with Stefan Walzer. The expected "result" value for every key is zero, instead of computed from a hash. Entropy for queries not to be false positives comes from free variables ("overhead") in the solution structure, which are populated pseudorandomly. Construction is slightly faster for not tracking result values, and never fails. Instead, FP rate can jump up whenever and whereever entries are packed too tightly. For small structures, we can choose overhead to make this FP rate jump unlikely, as seen in updated unit test CompactnessAndBacktrackAndFpRate.

Unlike standard Ribbon, Homogeneous Ribbon seems to scale to arbitrary number of keys when accepting an FP rate penalty for small pockets of high FP rate in the structure. For example, 64-bit ribbon with 8 solution columns and 10% allocated space overhead for slots seems to achieve about 10.5% space overhead vs. information-theoretic minimum based on its observed FP rate with expected pockets of degradation. (FP rate is close to 1/256.) If targeting a higher FP rate with fewer solution columns, Homogeneous Ribbon can be even more space efficient, because the penalty from degradation is relatively smaller. If targeting a lower FP rate, Homogeneous Ribbon is less space efficient, as more allocated overhead is needed to keep the FP rate impact of degradation relatively under control. The new OptimizeHomogAtScale tool in ribbon_test helps to find these optimal allocation overheads for different numbers of solution columns. And Ribbon widths, with 128-bit Ribbon apparently cutting space overheads in half vs. 64-bit.

Other misc item specifics:
* Ribbon APIs in util/ribbon_config.h now provide configuration data for not just 5% construction failure rate (95% success), but also 50% and 0.1%.
  * Note that the Ribbon structure does not exhibit "threshold" behavior as standard Xor filter does, so there is a roughly fixed space penalty to cut construction failure rate in half. Thus, there isn't really an "almost sure" setting.
  * Although we can extrapolate settings for large filters, we don't have a good formula for configuring smaller filters (< 2^17 slots or so), and efforts to summarize with a formula have failed. Thus, small data is hard-coded from updated FindOccupancy tool.
* Enhances ApproximateNumEntries for public API Ribbon using more precise data (new API GetNumToAdd), thus a more accurate but not perfect reversal of CalculateSpace. (bloom_test updated to expect the greater precision)
* Move EndianSwapValue from coding.h to coding_lean.h to keep Ribbon code easily transferable from RocksDB
* Add some missing 'const' to member functions
* Small optimization to 128-bit BitParity
* Small refactoring of BandingStorage in ribbon_alg.h to support Homogeneous Ribbon
* CompactnessAndBacktrackAndFpRate now has an "expand" test: on construction failure, a possible alternative to re-seeding hash functions is simply to increase the number of slots (allocated space overhead) and try again with essentially the same hash values. (Start locations will be different roundings of the same scaled hash values--because fastrange not mod.) This seems to be as effective or more effective than re-seeding, as long as we increase the number of slots (m) by roughly m += m/w where w is the Ribbon width. This way, there is effectively an expansion by one slot for each ribbon-width window in the banding. (This approach assumes that getting "bad data" from your hash function is as unlikely as it naturally should be, e.g. no adversary.)
* 32-bit and 16-bit Ribbon configurations are added to ribbon_test for understanding their behavior, e.g. with FindOccupancy. They are not considered useful at this time and not tested with CompactnessAndBacktrackAndFpRate.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7879

Test Plan: unit test updates included

Reviewed By: jay-zhuang

Differential Revision: D26371245

Pulled By: pdillinger

fbshipit-source-id: da6600d90a3785b99ad17a88b2a3027710b4ea3a
2021-02-26 08:50:42 -08:00
xinyuliu
b085ee13e0 Append all characters not captured by xsputn() in overflow() function (#7991)
Summary:
In the adapter class `WritableFileStringStreamAdapter`, which wraps WritableFile to be used for std::ostream, previouly only `std::endl` is considered a special case because `endl` is written by `os.put()` directly without going through `xsputn()`. `os.put()` will call `sputc()` and if we further check the internal implementation of `sputc()`, we will see it is
```
int_type __CLR_OR_THIS_CALL sputc(_Elem _Ch) {  // put a character
    return 0 < _Pnavail() ? _Traits::to_int_type(*_Pninc() = _Ch) : overflow(_Traits::to_int_type(_Ch));
```
As we explicitly disabled buffering, _Pnavail() is always 0. Thus every write, not captured by xsputn, becomes an overflow.

When I run tests on Windows, I found not only `std::endl` will drop into this case, writing an unsigned long long will also call `os.put()` then followed by `sputc()` and eventually call `overflow()`. Therefore, instead of only checking `std::endl`, we should try to append other characters as well unless the appending operation fails.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7991

Reviewed By: jay-zhuang

Differential Revision: D26615692

Pulled By: ajkr

fbshipit-source-id: 4c0003de1645b9531545b23df69b000e07014468
2021-02-23 21:44:48 -08:00
Akanksha Mahajan
cd79a00903 Make BlockBasedTable::kMaxAutoReadAheadSize configurable (#7951)
Summary:
RocksDB does auto-readahead for iterators on noticing more
than two reads for a table file. The readahead starts at 8KB and doubles on every
additional read upto BlockBasedTable::kMaxAutoReadAheadSize which is
256*1024.
This PR adds a new option BlockBasedTableOptions::max_auto_readahead_size which
replaces BlockBasedTable::kMaxAutoReadAheadSize and the new option can be
configured.
If max_auto_readahead_size is set 0 then no implicit auto prefetching will
be done. If max_auto_readahead_size provided is less than
8KB (which is initial readahead size used by rocksdb in case of
auto-readahead), readahead size will remain same as max_auto_readahead_size.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7951

Test Plan: Add new unit test case.

Reviewed By: anand1976

Differential Revision: D26568085

Pulled By: akankshamahajan15

fbshipit-source-id: b6543520fc74e97d859f2002328d4c5254d417af
2021-02-23 16:54:08 -08:00
Andrew Kryczka
daca92c17a Pick samples for compression dictionary using prime number (#7987)
Summary:
The sample selection technique taken in https://github.com/facebook/rocksdb/issues/7970 was problematic
because it had two code paths for sample selection depending on the
number of data blocks, and one of those code paths involved an
allocation. Using prime numbers, we can consolidate into one code path
without allocation. The downside is there will be values of N (number of
data blocks buffered) that suffer from poor spread in the selected
samples.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7987

Test Plan: `make check -j48`

Reviewed By: pdillinger

Differential Revision: D26586147

Pulled By: ajkr

fbshipit-source-id: 62028e54336fadb6e2c7a7fe6747daa05a263d32
2021-02-22 17:43:03 -08:00
Andrew Kryczka
d904233d2f Limit buffering for collecting samples for compression dictionary (#7970)
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
2021-02-19 14:09:54 -08:00
Ziyue Yang
0c2d71edba Fix typo: replace readadhead with readahead (#7953)
Summary:
This PR replaces several "readadhead" typos with "readahead".

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7953

Reviewed By: ajkr

Differential Revision: D26518903

Pulled By: jay-zhuang

fbshipit-source-id: 6f7dece0e39ec4f71c4a936399bcb2e02574f42a
2021-02-18 14:31:20 -08:00
Peter Dillinger
e4f1e64c30 Add prefetching (batched MultiGet) for experimental Ribbon filter (#7889)
Summary:
Adds support for prefetching data in Ribbon queries,
which especially optimizes batched Ribbon queries for MultiGet
(~222ns/key to ~97ns/key) but also single key queries on cold memory
(~333ns to ~226ns) because many queries span more than one cache line.

This required some refactoring of the query algorithm, and there
does not appear to be a noticeable regression in "hot memory" query
times (perhaps from 48ns to 50ns).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7889

Test Plan:
existing unit tests, plus performance validation with
filter_bench:

Each data point is the best of two runs. I saturated the machine
CPUs with other filter_bench runs in the background.

Before:

    $ ./filter_bench -impl=3 -m_keys_total_max=200 -average_keys_per_filter=100000 -m_queries=50
    WARNING: Assertions are enabled; benchmarks unnecessarily slow
    Building...
    Build avg ns/key: 125.86
    Number of filters: 1993
    Total size (MB): 168.166
    Reported total allocated memory (MB): 183.211
    Reported internal fragmentation: 8.94626%
    Bits/key stored: 7.05341
    Prelim FP rate %: 0.951827
    ----------------------------
    Mixed inside/outside queries...
      Single filter net ns/op: 48.0111
      Batched, prepared net ns/op: 222.384
      Batched, unprepared net ns/op: 343.908
      Skewed 50% in 1% net ns/op: 252.916
      Skewed 80% in 20% net ns/op: 320.579
      Random filter net ns/op: 332.957

After:

    $ ./filter_bench -impl=3 -m_keys_total_max=200 -average_keys_per_filter=100000 -m_queries=50
    WARNING: Assertions are enabled; benchmarks unnecessarily slow
    Building...
    Build avg ns/key: 128.117
    Number of filters: 1993
    Total size (MB): 168.166
    Reported total allocated memory (MB): 183.211
    Reported internal fragmentation: 8.94626%
    Bits/key stored: 7.05341
    Prelim FP rate %: 0.951827
    ----------------------------
    Mixed inside/outside queries...
      Single filter net ns/op: 49.8812
      Batched, prepared net ns/op: 97.1514
      Batched, unprepared net ns/op: 222.025
      Skewed 50% in 1% net ns/op: 197.48
      Skewed 80% in 20% net ns/op: 212.457
      Random filter net ns/op: 226.464

Bloom comparison, for reference:

    $ ./filter_bench -impl=2 -m_keys_total_max=200 -average_keys_per_filter=100000 -m_queries=50
    WARNING: Assertions are enabled; benchmarks unnecessarily slow
    Building...
    Build avg ns/key: 35.3042
    Number of filters: 1993
    Total size (MB): 238.488
    Reported total allocated memory (MB): 262.875
    Reported internal fragmentation: 10.2255%
    Bits/key stored: 10.0029
    Prelim FP rate %: 0.965327
    ----------------------------
    Mixed inside/outside queries...
      Single filter net ns/op: 9.09931
      Batched, prepared net ns/op: 34.21
      Batched, unprepared net ns/op: 88.8564
      Skewed 50% in 1% net ns/op: 139.75
      Skewed 80% in 20% net ns/op: 181.264
      Random filter net ns/op: 173.88

Reviewed By: jay-zhuang

Differential Revision: D26378710

Pulled By: pdillinger

fbshipit-source-id: 058428967c55ed763698284cd3b4bbe3351b6e69
2021-02-10 21:04:56 -08:00
mrambacher
12f1137355 Add a SystemClock class to capture the time functions of an Env (#7858)
Summary:
Introduces and uses a SystemClock class to RocksDB.  This class contains the time-related functions of an Env and these functions can be redirected from the Env to the SystemClock.

Many of the places that used an Env (Timer, PerfStepTimer, RepeatableThread, RateLimiter, WriteController) for time-related functions have been changed to use SystemClock instead.  There are likely more places that can be changed, but this is a start to show what can/should be done.  Over time it would be nice to migrate most (if not all) of the uses of the time functions from the Env to the SystemClock.

There are several Env classes that implement these functions.  Most of these have not been converted yet to SystemClock implementations; that will come in a subsequent PR.  It would be good to unify many of the Mock Timer implementations, so that they behave similarly and be tested similarly (some override Sleep, some use a MockSleep, etc).

Additionally, this change will allow new methods to be introduced to the SystemClock (like https://github.com/facebook/rocksdb/issues/7101 WaitFor) in a consistent manner across a smaller number of classes.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7858

Reviewed By: pdillinger

Differential Revision: D26006406

Pulled By: mrambacher

fbshipit-source-id: ed10a8abbdab7ff2e23d69d85bd25b3e7e899e90
2021-01-25 22:09:11 -08:00
Adam Retter
6e0f62f2b6 Add more tests to ASSERT_STATUS_CHECKED (3), API change (#7715)
Summary:
Third batch of adding more tests to ASSERT_STATUS_CHECKED.

* db_compaction_filter_test
* db_compaction_test
* db_dynamic_level_test
* db_inplace_update_test
* db_sst_test
* db_tailing_iter_test
* db_io_failure_test

Also update GetApproximateSizes APIs to all return Status.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7715

Reviewed By: jay-zhuang

Differential Revision: D25806896

Pulled By: pdillinger

fbshipit-source-id: 6cb9d62ba5a756c645812754c596ad3995d7c262
2021-01-06 14:15:02 -08:00
mrambacher
c1a65a4de4 Make StringEnv, StringSink, StringSource use FS classes (#7786)
Summary:
Change the StringEnv and related classes to be based on FileSystem APIs rather than the corresponding Env ones.  The StringSink and StringSource classes were changed to be based on the corresponding FS file classes.

Part of a cleanup to use the newer interfaces.  This change also eliminates some of the casts/wrappers to LegacyFile classes.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7786

Reviewed By: jay-zhuang

Differential Revision: D25761460

Pulled By: anand1976

fbshipit-source-id: 428ae8e32b3db97dbeeca08c9d3bb0d9d4d3a38f
2021-01-04 16:01:01 -08:00
Akanksha Mahajan
30a5ed9c53 Update "num_data_read" stat in RetrieveMultipleBlocks (#7770)
Summary:
RetrieveMultipleBlocks which is used by MultiGet to read data blocks is not updating num_data_read stat in
GetContextStats.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7770

Test Plan: make check -j64

Reviewed By: anand1976

Differential Revision: D25538982

Pulled By: akankshamahajan15

fbshipit-source-id: e3daedb035b1be8ab6af6f115cb3793ccc7b1ec6
2020-12-23 15:16:46 -08:00
mrambacher
02418194d7 Add more tests for assert status checked (#7524)
Summary:
Added 10 more tests that pass the ASSERT_STATUS_CHECKED test.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7524

Reviewed By: akankshamahajan15

Differential Revision: D24323093

Pulled By: ajkr

fbshipit-source-id: 28d4106d0ca1740c3b896c755edf82d504b74801
2020-12-22 23:45:58 -08:00
Peter Dillinger
4d897e51df Migrate away from Travis+Linux+amd64 (#7791)
Summary:
This disables Linux/amd64 builds in Travis for PRs, and adds a
gcc-10+c++20 build in CircleCI, which should fill out sufficient coverage
vs. what we had in Travis

Fixed a use of std::is_pod, which is deprecated in c++20

Fixed ++ on a volatile in db_repl_stress.cc, with bigger refactoring.
Although ++ on this volatile was probably ok with one thread writer and
one thread reader, the code was still overly complex. There was a
deadcode check for error
`if (replThread.no_read < dataPump.no_records)` which can be proven
never to happen based on the structure of the code. It infinite loops
instead for the case intended to be checked. I just simplified the code
for what should be the same checking power.

Also most configurations seem to be using make parallelism = 2 * vcores,
so fixing / using that.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7791

Test Plan:
CI
and `while ./db_repl_stress; do echo again; done` for a while

Reviewed By: siying

Differential Revision: D25669834

Pulled By: pdillinger

fbshipit-source-id: b2c688053d0b1d52c989903449d3cd27a04130d6
2020-12-22 00:20:57 -08:00
Peter Dillinger
239d17a19c Support optimize_filters_for_memory for Ribbon filter (#7774)
Summary:
Primarily this change refactors the optimize_filters_for_memory
code for Bloom filters, based on malloc_usable_size, to also work for
Ribbon filters.

This change also replaces the somewhat slow but general
BuiltinFilterBitsBuilder::ApproximateNumEntries with
implementation-specific versions for Ribbon (new) and Legacy Bloom
(based on a recently deleted version). The reason is to emphasize
speed in ApproximateNumEntries rather than 100% accuracy.

Justification: ApproximateNumEntries (formerly CalculateNumEntry) is
only used by RocksDB for range-partitioned filters, called each time we
start to construct one. (In theory, it should be possible to reuse the
estimate, but the abstractions provided by FilterPolicy don't really
make that workable.) But this is only used as a heuristic estimate for
hitting a desired partitioned filter size because of alignment to data
blocks, which have various numbers of unique keys or prefixes. The two
factors lead us to prioritize reasonable speed over 100% accuracy.

optimize_filters_for_memory adds extra complication, because precisely
calculating num_entries for some allowed number of bytes depends on state
with optimize_filters_for_memory enabled. And the allocator-agnostic
implementation of optimize_filters_for_memory, using malloc_usable_size,
means we would have to actually allocate memory, many times, just to
precisely determine how many entries (keys) could be added and stay below
some size budget, for the current state. (In a draft, I got this
working, and then realized the balance of speed vs. accuracy was all
wrong.)

So related to that, I have made CalculateSpace, an internal-only API
only used for testing, non-authoritative also if
optimize_filters_for_memory is enabled. This simplifies some code.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7774

Test Plan:
unit test updated, and for FilterSize test, range of tested
values is greatly expanded (still super fast)

Also tested `db_bench -benchmarks=fillrandom,stats -bloom_bits=10 -num=1000000 -partition_index_and_filters -format_version=5 [-optimize_filters_for_memory] [-use_ribbon_filter]` with temporary debug output of generated filter sizes.

Bloom+optimize_filters_for_memory:

      1 Filter size: 197 (224 in memory)
    134 Filter size: 3525 (3584 in memory)
    107 Filter size: 4037 (4096 in memory)
    Total on disk: 904,506
    Total in memory: 918,752

Ribbon+optimize_filters_for_memory:

      1 Filter size: 3061 (3072 in memory)
    110 Filter size: 3573 (3584 in memory)
     58 Filter size: 4085 (4096 in memory)
    Total on disk: 633,021 (-30.0%)
    Total in memory: 634,880 (-30.9%)

Bloom (no offm):

      1 Filter size: 261 (320 in memory)
      1 Filter size: 3333 (3584 in memory)
    240 Filter size: 3717 (4096 in memory)
    Total on disk: 895,674 (-1% on disk vs. +offm; known tolerable overhead of offm)
    Total in memory: 986,944 (+7.4% vs. +offm)

Ribbon (no offm):

      1 Filter size: 2949 (3072 in memory)
      1 Filter size: 3381 (3584 in memory)
    167 Filter size: 3701 (4096 in memory)
    Total on disk: 624,397 (-30.3% vs. Bloom)
    Total in memory: 690,688 (-30.0% vs. Bloom)

Note that optimize_filters_for_memory is even more effective for Ribbon filter than for cache-local Bloom, because it can close the unused memory gap even tighter than Bloom filter, because of 16 byte increments for Ribbon vs. 64 byte increments for Bloom.

Reviewed By: jay-zhuang

Differential Revision: D25592970

Pulled By: pdillinger

fbshipit-source-id: 606fdaa025bb790d7e9c21601e8ea86e10541912
2020-12-18 14:31:03 -08:00
Peter Dillinger
003e72b201 Use size_t for filter APIs, protect against overflow (#7726)
Summary:
Deprecate CalculateNumEntry and replace with
ApproximateNumEntries (better name) using size_t instead of int and
uint32_t, to minimize confusing casts and bad overflow behavior
(possible though probably not realistic). Bloom sizes are now explicitly
capped at max size supported by implementations: just under 4GiB for
fv=5 Bloom, and just under 512MiB for fv<5 Legacy Bloom. This
hardening could help to set up for fuzzing.

Also, since RocksDB only uses this information as an approximation
for trying to hit certain sizes for partitioned filters, it's more important
that the function be reasonably fast than for it to be completely
accurate. It's hard enough to be 100% accurate for Ribbon (currently
reversing CalculateSpace) that adding optimize_filters_for_memory
into the mix is just not worth trying to be 100% accurate for num
entries for bytes.

Also:
- Cleaned up filter_policy.h to remove MSVC warning handling and
potentially unsafe use of exception for "not implemented"
- Correct the number of entries limit beyond which current Ribbon
implementation falls back on Bloom instead.
- Consistently use "num_entries" rather than "num_entry"
- Remove LegacyBloomBitsBuilder::CalculateNumEntry as it's essentially
obsolete from general implementation
BuiltinFilterBitsBuilder::CalculateNumEntries.
- Fix filter_bench to skip some tests that don't make sense when only
one or a small number of filters has been generated.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7726

Test Plan:
expanded existing unit tests for CalculateSpace /
ApproximateNumEntries. Also manually used filter_bench to verify Legacy and
fv=5 Bloom size caps work (much too expensive for unit test). Note that
the actual bits per key is below requested due to space cap.

    $ ./filter_bench -impl=0 -bits_per_key=20 -average_keys_per_filter=256000000 -vary_key_count_ratio=0 -m_keys_total_max=256 -allow_bad_fp_rate
    ...
    Total size (MB): 511.992
    Bits/key stored: 16.777
    ...
    $ ./filter_bench -impl=2 -bits_per_key=20 -average_keys_per_filter=2000000000 -vary_key_count_ratio=0 -m_keys_total_max=2000
    ...
    Total size (MB): 4096
    Bits/key stored: 17.1799
    ...
    $

Reviewed By: jay-zhuang

Differential Revision: D25239800

Pulled By: pdillinger

fbshipit-source-id: f94e6d065efd31e05ec630ae1a82e6400d8390c4
2020-12-11 22:18:12 -08:00
anand76
8a1488efbf Ensure that MultiGet works properly with compressed cache (#7756)
Summary:
Ensure that when direct IO is enabled and a compressed block cache is
configured, MultiGet inserts compressed data blocks into the compressed
block cache.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7756

Test Plan: Add unit test to db_basic_test

Reviewed By: cheng-chang

Differential Revision: D25416240

Pulled By: anand1976

fbshipit-source-id: 75d57526370c9c0a45ff72651f3278dbd8a9086f
2020-12-09 17:01:13 -08:00
Jay Zhuang
9e1640403a Exclude timestamp from prefix extractor (#7668)
Summary:
Timestamp should not be included in prefix extractor, as we discussed here: https://github.com/facebook/rocksdb/pull/7589#discussion_r511068586

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7668

Test Plan: added unittest

Reviewed By: riversand963

Differential Revision: D24966265

Pulled By: jay-zhuang

fbshipit-source-id: 0dae618c333d4b7942a40d556535a1795e060aea
2020-12-01 14:07:15 -08:00
Yanqin Jin
84a700819e Fix the logic of setting read_amp_bytes_per_bit from OPTIONS file (#7680)
Summary:
Instead of using `EncodeFixed32` which always serialize a integer to
little endian, we should use the local machine's endianness when
populating a native data structure during options parsing.
Without this fix, `read_amp_bytes_per_bit` may be populated incorrectly
on big-endian machines.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7680

Test Plan: make check

Reviewed By: pdillinger

Differential Revision: D24999166

Pulled By: riversand963

fbshipit-source-id: dc603cff6e17f8fa32479ce6df93b93082e6b0c4
2020-11-17 00:44:30 -08:00
Yanqin Jin
9aa1b1dc19 Hack to load OPTIONS file for read_amp_bytes_per_bit (#7659)
Summary:
A temporary hack to work around a bug in 6.10, 6.11, 6.12, 6.13 and
6.14. The bug will write out 8 bytes to OPTIONS file from the starting
address of BlockBasedTableOptions.read_amp_bytes_per_bit which is
actually a uint32. Consequently, the value of read_amp_bytes_per_bit
written in the OPTIONS file is wrong. From 6.15, RocksDB will
try to parse the read_amp_bytes_per_bit from OPTIONS file as a uint32.
To be able to load OPTIONS file generated by affected releases before
the fix, we need to manually parse read_amp_bytes_per_bit with this hack.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7659

Test Plan:
Generate a db with current 6.14.fb (head at b6db05dbb5). Maybe use db_stress.

Checkout this PR, run
```
 ~/rocksdb/ldb --db=. --try_load_options --ignore_unknown_options idump --count_only
```
Expect success, and should not see
```
Failed: Invalid argument: Error parsing read_amp_bytes_per_bit:17179869184
```

Also
make check

Reviewed By: anand1976

Differential Revision: D24954752

Pulled By: riversand963

fbshipit-source-id: c7b802fc3e52acd050a4fc1cd475016122234394
2020-11-13 11:52:50 -08:00
Peter Dillinger
60af964372 Experimental (production candidate) SST schema for Ribbon filter (#7658)
Summary:
Added experimental public API for Ribbon filter:
NewExperimentalRibbonFilterPolicy(). This experimental API will
take a "Bloom equivalent" bits per key, and configure the Ribbon
filter for the same FP rate as Bloom would have but ~30% space
savings. (Note: optimize_filters_for_memory is not yet implemented
for Ribbon filter. That can be added with no effect on schema.)

Internally, the Ribbon filter is configured using a "one_in_fp_rate"
value, which is 1 over desired FP rate. For example, use 100 for 1%
FP rate. I'm expecting this will be used in the future for configuring
Bloom-like filters, as I expect people to more commonly hold constant
the filter accuracy and change the space vs. time trade-off, rather than
hold constant the space (per key) and change the accuracy vs. time
trade-off, though we might make that available.

### Benchmarking

```
$ ./filter_bench -impl=2 -quick -m_keys_total_max=200 -average_keys_per_filter=100000 -net_includes_hashing
Building...
Build avg ns/key: 34.1341
Number of filters: 1993
Total size (MB): 238.488
Reported total allocated memory (MB): 262.875
Reported internal fragmentation: 10.2255%
Bits/key stored: 10.0029
----------------------------
Mixed inside/outside queries...
  Single filter net ns/op: 18.7508
  Random filter net ns/op: 258.246
    Average FP rate %: 0.968672
----------------------------
Done. (For more info, run with -legend or -help.)
$ ./filter_bench -impl=3 -quick -m_keys_total_max=200 -average_keys_per_filter=100000 -net_includes_hashing
Building...
Build avg ns/key: 130.851
Number of filters: 1993
Total size (MB): 168.166
Reported total allocated memory (MB): 183.211
Reported internal fragmentation: 8.94626%
Bits/key stored: 7.05341
----------------------------
Mixed inside/outside queries...
  Single filter net ns/op: 58.4523
  Random filter net ns/op: 363.717
    Average FP rate %: 0.952978
----------------------------
Done. (For more info, run with -legend or -help.)
```

168.166 / 238.488 = 0.705  -> 29.5% space reduction

130.851 / 34.1341 = 3.83x construction time for this Ribbon filter vs. lastest Bloom filter (could make that as little as about 2.5x for less space reduction)

### Working around a hashing "flaw"

bloom_test discovered a flaw in the simple hashing applied in
StandardHasher when num_starts == 1 (num_slots == 128), showing an
excessively high FP rate.  The problem is that when many entries, on the
order of number of hash bits or kCoeffBits, are associated with the same
start location, the correlation between the CoeffRow and ResultRow (for
efficiency) can lead to a solution that is "universal," or nearly so, for
entries mapping to that start location. (Normally, variance in start
location breaks the effective association between CoeffRow and
ResultRow; the same value for CoeffRow is effectively different if start
locations are different.) Without kUseSmash and with num_starts > 1 (thus
num_starts ~= num_slots), this flaw should be completely irrelevant.  Even
with 10M slots, the chances of a single slot having just 16 (or more)
entries map to it--not enough to cause an FP problem, which would be local
to that slot if it happened--is 1 in millions. This spreadsheet formula
shows that: =1/(10000000*(1 - POISSON(15, 1, TRUE)))

As kUseSmash==false (the setting for Standard128RibbonBitsBuilder) is
intended for CPU efficiency of filters with many more entries/slots than
kCoeffBits, a very reasonable work-around is to disallow num_starts==1
when !kUseSmash, by making the minimum non-zero number of slots
2*kCoeffBits. This is the work-around I've applied. This also means that
the new Ribbon filter schema (Standard128RibbonBitsBuilder) is not
space-efficient for less than a few hundred entries. Because of this, I
have made it fall back on constructing a Bloom filter, under existing
schema, when that is more space efficient for small filters. (We can
change this in the future if we want.)

TODO: better unit tests for this case in ribbon_test, and probably
update StandardHasher for kUseSmash case so that it can scale nicely to
small filters.

### Other related changes

* Add Ribbon filter to stress/crash test
* Add Ribbon filter to filter_bench as -impl=3
* Add option string support, as in "filter_policy=experimental_ribbon:5.678;"
where 5.678 is the Bloom equivalent bits per key.
* Rename internal mode BloomFilterPolicy::kAuto to kAutoBloom
* Add a general BuiltinFilterBitsBuilder::CalculateNumEntry based on
binary searching CalculateSpace (inefficient), so that subclasses
(especially experimental ones) don't have to provide an efficient
implementation inverting CalculateSpace.
* Minor refactor FastLocalBloomBitsBuilder for new base class
XXH3pFilterBitsBuilder shared with new Standard128RibbonBitsBuilder,
which allows the latter to fall back on Bloom construction in some
extreme cases.
* Mostly updated bloom_test for Ribbon filter, though a test like
FullBloomTest::Schema is a next TODO to ensure schema stability
(in case this becomes production-ready schema as it is).
* Add some APIs to ribbon_impl.h for configuring Ribbon filters.
Although these are reasonably covered by bloom_test, TODO more unit
tests in ribbon_test
* Added a "tool" FindOccupancyForSuccessRate to ribbon_test to get data
for constructing the linear approximations in GetNumSlotsFor95PctSuccess.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7658

Test Plan:
Some unit tests updated but other testing is left TODO. This
is considered experimental but laying down schema compatibility as early
as possible in case it proves production-quality. Also tested in
stress/crash test.

Reviewed By: jay-zhuang

Differential Revision: D24899349

Pulled By: pdillinger

fbshipit-source-id: 9715f3e6371c959d923aea8077c9423c7a9f82b8
2020-11-12 20:46:14 -08:00
mrambacher
c442f6809f Create a Customizable class to load classes and configurations (#6590)
Summary:
The Customizable class is an extension of the Configurable class and allows instances to be created by a name/ID.  Classes that extend customizable can define their Type (e.g. "TableFactory", "Cache") and  a method to instantiate them (TableFactory::CreateFromString).  Customizable objects can be registered with the ObjectRegistry and created dynamically.

Future PRs will make more types of objects extend Customizable.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/6590

Reviewed By: cheng-chang

Differential Revision: D24841553

Pulled By: zhichao-cao

fbshipit-source-id: d0c2132bd932e971cbfe2c908ca2e5db30c5e155
2020-11-11 15:10:41 -08:00
Huisheng Liu
16d103d35b fix read_amp_bytes_per_bit field size (#7651)
Summary:
The field in BlockBasedTableOptions is 4 bytes:
  // Default: 0 (disabled)
  uint32_t read_amp_bytes_per_bit = 0;

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7651

Reviewed By: ltamasi

Differential Revision: D24844994

Pulled By: riversand963

fbshipit-source-id: e2695e55532256ef8996dd6939cad06987a80293
2020-11-10 11:14:48 -08:00
Jay Zhuang
881e0dcc09 Fix MultiGet unable to query timestamp data issue (#7589)
Summary:
The filter query key should not contain timestamp. The timestamp is
stripped for Get(), but not MultiGet().

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7589

Reviewed By: riversand963

Differential Revision: D24494661

Pulled By: jay-zhuang

fbshipit-source-id: fc5ff40f9d683a89a760c6ff0ab3aed05a70c317
2020-11-03 09:45:41 -08:00
Yanqin Jin
394210f280 Remove unused includes (#7604)
Summary:
This is a PR generated **semi-automatically** by an internal tool to remove unused includes and `using` statements.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7604

Test Plan: make check

Reviewed By: ajkr

Differential Revision: D24579392

Pulled By: riversand963

fbshipit-source-id: c4bfa6c6b08da1de186690d37eb73d8fff45aecd
2020-10-28 23:22:27 -07:00
Ramkumar Vadivelu
9a690a74e1 In ParseInternalKey(), include corrupt key info in Status (#7515)
Summary:
Fixes Issue https://github.com/facebook/rocksdb/issues/7497

When allow_data_in_errors db_options is set, log error key details in `ParseInternalKey()`

Have fixed most of the calls. Have few TODOs still pending - because have to make more deeper changes to pass in the allow_data_in_errors flag. Will do those in a separate PR later.

Tests:
- make check
- some of the existing tests that exercise the "internal key too small" condition are: dbformat_test, cuckoo_table_builder_test
- some of the existing tests that exercise the corrupted key path are: corruption_test, merge_helper_test, compaction_iterator_test

Example of new status returns:
- Key too small - `Corrupted Key: Internal Key too small. Size=5`
- Corrupt key with allow_data_in_errors option set to false: `Corrupted Key: '<redacted>' seq:3, type:3`
- Corrupt key with allow_data_in_errors option set to true: `Corrupted Key: '61' seq:3, type:3`

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7515

Reviewed By: ajkr

Differential Revision: D24240264

Pulled By: ramvadiv

fbshipit-source-id: bc48f5d4475ac19d7713e16df37505b31aac42e7
2020-10-28 10:12:58 -07:00
mrambacher
f35f7f2704 Fix many tests to run with MEM_ENV and ENCRYPTED_ENV; Introduce a MemoryFileSystem class (#7566)
Summary:
This PR does a few things:

1.  The MockFileSystem class was split out from the MockEnv.  This change would theoretically allow a MockFileSystem to be used by other Environments as well (if we created a means of constructing one).  The MockFileSystem implements a FileSystem in its entirety and does not rely on any Wrapper implementation.

2.  Make the RocksDB test suite work when MOCK_ENV=1 and ENCRYPTED_ENV=1 are set.  To accomplish this, a few things were needed:
- The tests that tried to use the "wrong" environment (Env::Default() instead of env_) were updated
- The MockFileSystem was changed to support the features it was missing or mishandled (such as recursively deleting files in a directory or supporting renaming of a directory).

3.  Updated the test framework to have a ROCKSDB_GTEST_SKIP macro.  This can be used to flag tests that are skipped.  Currently, this defaults to doing nothing (marks the test as SUCCESS) but will mark the tests as SKIPPED when RocksDB is upgraded to a version of gtest that supports this (gtest-1.10).

I have run a full "make check" with MEM_ENV, ENCRYPTED_ENV,  both, and neither under both MacOS and RedHat.  A few tests were disabled/skipped for the MEM/ENCRYPTED cases.  The error_handler_fs_test fails/hangs for MEM_ENV (presumably a timing problem) and I will introduce another PR/issue to track that problem.  (I will also push a change to disable those tests soon).  There is one more test in DBTest2 that also fails which I need to investigate or skip before this PR is merged.

Theoretically, this PR should also allow the test suite to run against an Env loaded from the registry, though I do not have one to try it with currently.

Finally, once this is accepted, it would be nice if there was a CircleCI job to run these tests on a checkin so this effort does not become stale.  I do not know how to do that, so if someone could write that job, it would be appreciated :)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7566

Reviewed By: zhichao-cao

Differential Revision: D24408980

Pulled By: jay-zhuang

fbshipit-source-id: 911b1554a4d0da06fd51feca0c090a4abdcb4a5f
2020-10-27 10:33:09 -07:00
Ziyue Yang
1c78e4b235 Make parallel compression optimization code tidier (#6888)
Summary:
This commit makes https://github.com/facebook/rocksdb/issues/6262's code change tidier and easier to understand by:

1. Wrapping parallel compression initialization and termination into
   common methods;
2. Wrapping BlockRep initialization, push/pop into common methods;
3. Wrapping file size estimation into common methods;
4. Fixing function declarations that use non-const reference;
5. Fixing some uninitialized variables;
6. Fixing first_block data race;
7. Making BlockRep::status check in BlockBasedTableBuilder::Finish only present
if ok();
8. Making assert(ok()) in BlockBasedTableBuilder::CompressAndVerifyBlock only
present in non-parallel compression mode. In parallel compression mode,
compression will abort if status is not OK;
9. Eliminating potential data race caused by BlockBasedTableBuilder::GetStatus()
and BlockBasedTableBuilder::GetIOStatus() by returning status copy instead of
unprotected reference.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/6888

Reviewed By: ajkr

Differential Revision: D21957110

Pulled By: jay-zhuang

fbshipit-source-id: 3a29892f249209513f030349756cecd7736eae80
2020-10-22 11:05:25 -07:00
mrambacher
1eda625eab Revert Statuses returned from pre-Configurable options functions (#7563)
Summary:
Further refinement of the earlier PR.  Now the Status is NotFound with a subcode of PathNotFound. Also the existing functions for options parsing/loading are reverted to return InvalidArgument no matter in which way the user-provided arguments are deemed invalid.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7563

Reviewed By: zhichao-cao

Differential Revision: D24422491

Pulled By: ajkr

fbshipit-source-id: ba6b237cd0584d3f925c5ba0d349aeb8c250af67
2020-10-20 11:53:28 -07:00
Akanksha Mahajan
b4cd51d847 Fix for stress test failure (#7574)
Summary:
Ignore read error in 'FilePrefetchBuffer::TryReadFromCache' as status is ignored
and  bool value is returned. Return error if prefetch fails in
'PrefetchTail' as we have planned to return Prefetch failures to users.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7574

Test Plan:
make check -j64,
python -u tools/db_crashtest.py blackbox

Reviewed By: zhichao-cao

Differential Revision: D24408825

Pulled By: akankshamahajan15

fbshipit-source-id: feebda771415998253fbe54632f13e6e75b7a243
2020-10-20 09:13:42 -07:00
anand76
00751e4292 Add a host location property to TableProperties (#7479)
Summary:
This PR adds support for writing a location identifier of the DB host to SST files as a table property. By default, the hostname is used, but can be overridden by the user. There have been some recent corruptions in files written by ```SstFileWriter``` before checksumming, so this property can be used to trace it back to the writing host and checking the host for hardware isues.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7479

Test Plan: Add new unit tests

Reviewed By: pdillinger

Differential Revision: D24340671

Pulled By: anand1976

fbshipit-source-id: 2038949fd8d160c0633ccb4f9da77740f19fa2a2
2020-10-19 11:38:48 -07:00
Akanksha Mahajan
db87afbcb3 Return error if Get/Multi() fails in Prefetching Filter blocks (#7543)
Summary:
Right now all I/O failures under
PartitionFilterBlock::CacheDependencies() is swallowed. Return error in
case prefetch fails.

On returning error in PartitionedFilterBlockReader::CacheDependencies was causing stress test failure because PrefetchBuffer is initialized with enable_ = true, as result when PosixMmapReadableFile::Read is called from Prefetch, scratch is ignored causing buffer to fill with garbage values. Initializing prefetch buffer by CreatePrefetchBuffer that sets enable_ with !ioptions.allow_mmap_reads fixed the problem as it returns without prefetching data if allow_mmap_reads is set.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7543

Test Plan:
make check -j64;
python -u tools/db_crashtest.py --simple blackbox

Reviewed By: anand1976

Differential Revision: D24284596

Pulled By: akankshamahajan15

fbshipit-source-id: f3f0fd44b59dcf60645730436f28564a07884868
2020-10-14 10:45:36 -07:00
Andrew Kryczka
75d3b6fdf0 Redesign block cache pinning API (#7520)
Summary:
The old flag-based APIs (`BlockBasedTableOptions::pin_l0_filter_and_index_blocks_in_cache` and `BlockBasedTableOptions::pin_top_level_index_and_filter`) were insufficient for our needs. For example, it was impossible to pin only unpartitioned meta-blocks, which could prevent block cache contention when turning on dictionary compression or during a migration to partitioned indexes/filters. It was also impossible to pin all meta-blocks in memory while having predictable memory usage via block cache. If we had continued adding flags to address these scenarios, they would have had significant overlap causing confusion. Instead, this PR deprecates the flags and starts a new API with non-overlapping options.

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

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

Reviewed By: pdillinger

Differential Revision: D24200034

Pulled By: ajkr

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

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

Reviewed By: zhichao-cao

Differential Revision: D24095887

Pulled By: akankshamahajan15

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

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

Reviewed By: anand1976

Differential Revision: D24127040

Pulled By: akankshamahajan15

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

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

Test Plan: Watch existing tests to succeed.

Reviewed By: riversand963

Differential Revision: D24119527

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

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

Reviewed By: ajkr

Differential Revision: D24100875

Pulled By: ltamasi

fbshipit-source-id: 8705e3e6e8be4b4fd175ffdb031baa6530b61151
2020-10-03 18:38:04 -07:00
Akanksha Mahajan
7d503e66a9 Return error if Get() fails in Prefetching Filter blocks (#7463)
Summary:
Right now all I/O failures under
PartitionFilterBlock::CacheDependencies() is swallowed. Return error in
case prefetch fails.

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

Test Plan: make check -j64

Reviewed By: anand1976

Differential Revision: D24008226

Pulled By: akankshamahajan15

fbshipit-source-id: b65d63b2d01465db92500b78de7ad58650ec9b3b
2020-10-02 19:40:43 -07:00
darionyaphet
2af46f1011 Move break into block (#7468)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/7468

Reviewed By: riversand963

Differential Revision: D24028736

Pulled By: ajkr

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

Change ParseInternalKey() to return Status instead of bool.

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

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

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

Reviewed By: ajkr

Differential Revision: D24002433

Pulled By: ramvadiv

fbshipit-source-id: ac253ecf577a29044c47c3fe254a01e71404c44c
2020-09-30 19:16:47 -07:00
Jay Zhuang
1bdaef7a06 Status check enforcement for timestamp_basic_test (#7454)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/7454

Reviewed By: riversand963

Differential Revision: D23981719

Pulled By: jay-zhuang

fbshipit-source-id: 01073f73e54c17067b886c4a2f179b2804198399
2020-09-29 18:23:27 -07:00