Commit Graph

166 Commits

Author SHA1 Message Date
sdong
5c1a544122 Clean up InternalIterator upper bound logic a little bit (#7200)
Summary:
IteratorIterator::IsOutOfBound() and IteratorIterator::MayBeOutOfUpperBound() are two functions that related to upper bound check. It is hard for users to reason about this complexity. Consolidate the two functions into one and assign an enum as results to improve readability.

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

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

Reviewed By: anand1976

Differential Revision: D22833181

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

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

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

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

Reviewed By: anand1976

Differential Revision: D22859246

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

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

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

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

Reviewed By: anand1976

Differential Revision: D22861323

Pulled By: ajkr

fbshipit-source-id: 54aebb3e89c872eeab0f5793b4b6e42878d093ce
2020-08-03 15:23:04 -07:00
Andrew Kryczka
643c863b72 minimize BlockIter comparator scope (#7149)
Summary:
PR https://github.com/facebook/rocksdb/issues/6944 transitioned `BlockIter` from using `Comparator*` to using
concrete `UserComparatorWrapper` and `InternalKeyComparator`. However,
adding them as instance variables to `BlockIter` was not optimal.
Bloating `BlockIter` caused the `ArenaWrappedDBIter`'s arena allocator to do more heap
allocations (in certain cases) which harmed performance of `DB::NewIterator()`. This PR
pushes down the concrete comparator objects to the point of usage, which
forces them to be on the stack. As a result, the `BlockIter` is back to
its original size prior to https://github.com/facebook/rocksdb/issues/6944 (actually a bit smaller since there
were two `Comparator*` before).

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

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

Reviewed By: riversand963

Differential Revision: D22623189

Pulled By: ajkr

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

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

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

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

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

Reviewed By: riversand963

Differential Revision: D22463160

Pulled By: pdillinger

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

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

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

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

setup command:

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

benchmark command:

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

Reviewed By: anand1976

Differential Revision: D22357032

Pulled By: ajkr

fbshipit-source-id: 8b01e9c1c2a4e9d02fc9dfe16c1cc0327f8bdf24
2020-07-09 12:27:20 -07:00
Akanksha Mahajan
54f171fe90 Update Flush policy in PartitionedIndexBuilder on switching from user-key to internal-key mode (#7096)
Summary:
When format_version is high enough to support user-key and
there are index entries for same user key that spans multiple data
blocks then it changes from user-key mode to internal-key mode. But the
flush policy is not reset to point to Block Builder of internal-keys.
After this switch, no entries are added to user key index partition
result, thus it never triggers flushing the block.

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

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

Test Plan: make check -j64

Reviewed By: ajkr

Differential Revision: D22416598

Pulled By: akankshamahajan15

fbshipit-source-id: 01fc2dc07ea1b32f8fb803995ebe6e9a3fbe67ac
2020-07-08 21:03:04 -07:00
Andrew Kryczka
dd29ad4223 Separate internal and user key comparators in BlockIter (#6944)
Summary:
Replace `BlockIter::comparator_` and `IndexBlockIter::user_comparator_wrapper_` with a concrete `UserComparatorWrapper` and `InternalKeyComparator`. The motivation for this change was the inconvenience of not knowing the concrete type of `BlockIter::comparator_`, which prevented calling specialized internal key comparison functions to optimize comparison of keys with global seqno applied.

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

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

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

benchmark run command:

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

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

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

Reviewed By: pdillinger

Differential Revision: D21924676

Pulled By: ajkr

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

Reviewed By: akankshamahajan15

Differential Revision: D22362857

Pulled By: pdillinger

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

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

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

Reviewed By: ajkr

Differential Revision: D22197734

Pulled By: akankshamahajan15

fbshipit-source-id: d87e9e46bccab8e896ee6979d6b79c51f73d479e
2020-07-01 14:58:08 -07:00
Anand Ananthabhotla
9a5886bd8c Extend Get/MultiGet deadline support to table open (#6982)
Summary:
Current implementation of the ```read_options.deadline``` option only checks the deadline for random file reads during point lookups. This PR extends the checks to file opens, prefetches and preloads as part of table open.

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

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

Test Plan: Add new unit tests in db_basic_test

Reviewed By: riversand963

Differential Revision: D22219515

Pulled By: anand1976

fbshipit-source-id: 8a3b92f4a889808013838603aa3ca35229cd501b
2020-06-29 14:53:17 -07:00
sdong
f9817201af Add unity build to CircleCI (#7026)
Summary:
We are still keeping unity build working. So it's a good idea to add to a pre-commit CI.
A latest GCC docker image just to get a little bit more coverage. Fix three small issues to make it pass.
Also make unity_test to run db_basic_test rather than db_test to cut the test time. There is no point to run expensive tests here. It was set to run db_test before db_basic_test was separated out.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7026

Test Plan: watch tests to pass.

Reviewed By: zhichao-cao

Differential Revision: D22223197

fbshipit-source-id: baa3b6cbb623bf359829b63ce35715c75bcb0ed4
2020-06-26 11:14:08 -07:00
Peter Dillinger
5b2bbacb6f Minimize memory internal fragmentation for Bloom filters (#6427)
Summary:
New experimental option BBTO::optimize_filters_for_memory builds
filters that maximize their use of "usable size" from malloc_usable_size,
which is also used to compute block cache charges.

Rather than always "rounding up," we track state in the
BloomFilterPolicy object to mix essentially "rounding down" and
"rounding up" so that the average FP rate of all generated filters is
the same as without the option. (YMMV as heavily accessed filters might
be unluckily lower accuracy.)

Thus, the option near-minimizes what the block cache considers as
"memory used" for a given target Bloom filter false positive rate and
Bloom filter implementation. There are no forward or backward
compatibility issues with this change, though it only works on the
format_version=5 Bloom filter.

With Jemalloc, we see about 10% reduction in memory footprint (and block
cache charge) for Bloom filters, but 1-2% increase in storage footprint,
due to encoding efficiency losses (FP rate is non-linear with bits/key).

Why not weighted random round up/down rather than state tracking? By
only requiring malloc_usable_size, we don't actually know what the next
larger and next smaller usable sizes for the allocator are. We pick a
requested size, accept and use whatever usable size it has, and use the
difference to inform our next choice. This allows us to narrow in on the
right balance without tracking/predicting usable sizes.

Why not weight history of generated filter false positive rates by
number of keys? This could lead to excess skew in small filters after
generating a large filter.

Results from filter_bench with jemalloc (irrelevant details omitted):

    (normal keys/filter, but high variance)
    $ ./filter_bench -quick -impl=2 -average_keys_per_filter=30000 -vary_key_count_ratio=0.9
    Build avg ns/key: 29.6278
    Number of filters: 5516
    Total size (MB): 200.046
    Reported total allocated memory (MB): 220.597
    Reported internal fragmentation: 10.2732%
    Bits/key stored: 10.0097
    Average FP rate %: 0.965228
    $ ./filter_bench -quick -impl=2 -average_keys_per_filter=30000 -vary_key_count_ratio=0.9 -optimize_filters_for_memory
    Build avg ns/key: 30.5104
    Number of filters: 5464
    Total size (MB): 200.015
    Reported total allocated memory (MB): 200.322
    Reported internal fragmentation: 0.153709%
    Bits/key stored: 10.1011
    Average FP rate %: 0.966313

    (very few keys / filter, optimization not as effective due to ~59 byte
     internal fragmentation in blocked Bloom filter representation)
    $ ./filter_bench -quick -impl=2 -average_keys_per_filter=1000 -vary_key_count_ratio=0.9
    Build avg ns/key: 29.5649
    Number of filters: 162950
    Total size (MB): 200.001
    Reported total allocated memory (MB): 224.624
    Reported internal fragmentation: 12.3117%
    Bits/key stored: 10.2951
    Average FP rate %: 0.821534
    $ ./filter_bench -quick -impl=2 -average_keys_per_filter=1000 -vary_key_count_ratio=0.9 -optimize_filters_for_memory
    Build avg ns/key: 31.8057
    Number of filters: 159849
    Total size (MB): 200
    Reported total allocated memory (MB): 208.846
    Reported internal fragmentation: 4.42297%
    Bits/key stored: 10.4948
    Average FP rate %: 0.811006

    (high keys/filter)
    $ ./filter_bench -quick -impl=2 -average_keys_per_filter=1000000 -vary_key_count_ratio=0.9
    Build avg ns/key: 29.7017
    Number of filters: 164
    Total size (MB): 200.352
    Reported total allocated memory (MB): 221.5
    Reported internal fragmentation: 10.5552%
    Bits/key stored: 10.0003
    Average FP rate %: 0.969358
    $ ./filter_bench -quick -impl=2 -average_keys_per_filter=1000000 -vary_key_count_ratio=0.9 -optimize_filters_for_memory
    Build avg ns/key: 30.7131
    Number of filters: 160
    Total size (MB): 200.928
    Reported total allocated memory (MB): 200.938
    Reported internal fragmentation: 0.00448054%
    Bits/key stored: 10.1852
    Average FP rate %: 0.963387

And from db_bench (block cache) with jemalloc:

    $ ./db_bench -db=/dev/shm/dbbench.no_optimize -benchmarks=fillrandom -format_version=5 -value_size=90 -bloom_bits=10 -num=2000000 -threads=8 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=false
    $ ./db_bench -db=/dev/shm/dbbench -benchmarks=fillrandom -format_version=5 -value_size=90 -bloom_bits=10 -num=2000000 -threads=8 -optimize_filters_for_memory -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=false
    $ (for FILE in /dev/shm/dbbench.no_optimize/*.sst; do ./sst_dump --file=$FILE --show_properties | grep 'filter block' ; done) | awk '{ t += $4; } END { print t; }'
    17063835
    $ (for FILE in /dev/shm/dbbench/*.sst; do ./sst_dump --file=$FILE --show_properties | grep 'filter block' ; done) | awk '{ t += $4; } END { print t; }'
    17430747
    $ #^ 2.1% additional filter storage
    $ ./db_bench -db=/dev/shm/dbbench.no_optimize -use_existing_db -benchmarks=readrandom,stats -statistics -bloom_bits=10 -num=2000000 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=false -duration=10 -cache_index_and_filter_blocks -cache_size=1000000000
    rocksdb.block.cache.index.add COUNT : 33
    rocksdb.block.cache.index.bytes.insert COUNT : 8440400
    rocksdb.block.cache.filter.add COUNT : 33
    rocksdb.block.cache.filter.bytes.insert COUNT : 21087528
    rocksdb.bloom.filter.useful COUNT : 4963889
    rocksdb.bloom.filter.full.positive COUNT : 1214081
    rocksdb.bloom.filter.full.true.positive COUNT : 1161999
    $ #^ 1.04 % observed FP rate
    $ ./db_bench -db=/dev/shm/dbbench -use_existing_db -benchmarks=readrandom,stats -statistics -bloom_bits=10 -num=2000000 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=false -optimize_filters_for_memory -duration=10 -cache_index_and_filter_blocks -cache_size=1000000000
    rocksdb.block.cache.index.add COUNT : 33
    rocksdb.block.cache.index.bytes.insert COUNT : 8448592
    rocksdb.block.cache.filter.add COUNT : 33
    rocksdb.block.cache.filter.bytes.insert COUNT : 18220328
    rocksdb.bloom.filter.useful COUNT : 5360933
    rocksdb.bloom.filter.full.positive COUNT : 1321315
    rocksdb.bloom.filter.full.true.positive COUNT : 1262999
    $ #^ 1.08 % observed FP rate, 13.6% less memory usage for filters

(Due to specific key density, this example tends to generate filters that are "worse than average" for internal fragmentation. "Better than average" cases can show little or no improvement.)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6427

Test Plan: unit test added, 'make check' with gcc, clang and valgrind

Reviewed By: siying

Differential Revision: D22124374

Pulled By: pdillinger

fbshipit-source-id: f3e3aa152f9043ddf4fae25799e76341d0d8714e
2020-06-22 13:32:07 -07:00
Peter Dillinger
25a0d0ca30 Fix block checksum for >=4GB, refactor (#6978)
Summary:
Although RocksDB falls over in various other ways with KVs
around 4GB or more, this change fixes how XXH32 and XXH64 were being
called by the block checksum code to support >= 4GB in case that should
ever happen, or the code copied for other uses.

This change is not a schema compatibility issue because the checksum
verification code would checksum the first (block_size + 1) mod 2^32
bytes while the checksum construction code would checksum the first
block_size mod 2^32 plus the compression type byte, meaning the
XXH32/64 checksums for >=4GB block would not match about 255/256 times.

While touching this code, I refactored to consolidate redundant
implementations, improving diagnostics and performance tracking in some
cases. Also used less confusing language in those diagnostics.

Makes https://github.com/facebook/rocksdb/issues/6875 obsolete.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6978

Test Plan:
I was able to write a test for this using an SST file writer
and VerifyChecksum in a reader. The test fails before the fix, though
I'm leaving the test disabled because I don't think it's worth the
expense of running regularly.

Reviewed By: gg814

Differential Revision: D22143260

Pulled By: pdillinger

fbshipit-source-id: 982993d16134e8c50bea2269047f901c1783726e
2020-06-19 16:18:24 -07:00
sdong
223b57eeb8 Fix the bug that compressed cache is disabled in read-only DBs (#6990)
Summary:
Compressed block cache is disabled in https://github.com/facebook/rocksdb/pull/4650 for no good reason. Re-enable it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6990

Test Plan: Add a unit test to make sure a general function works with read-only DB + compressed block cache.

Reviewed By: ltamasi

Differential Revision: D22072755

fbshipit-source-id: 2a55df6363de23a78979cf6c747526359e5dc7a1
2020-06-17 14:30:54 -07:00
Zitan Chen
94d04529de Store DB identity and DB session ID in SST files (#6983)
Summary:
`db_id` and `db_session_id` are now part of the table properties for all formats and stored in SST files. This adds about 99 bytes to each new SST file.

The `TablePropertiesNames` for these two identifiers are `rocksdb.creating.db.identity` and `rocksdb.creating.session.identity`.

In addition, SST files generated from SstFileWriter and Repairer have DB identity “SST Writer” and “DB Repairer”, respectively. Their DB session IDs are generated in the same way as `DB::GetDbSessionId`.

A table property test is added.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6983

Test Plan: make check and some manual tests.

Reviewed By: zhichao-cao

Differential Revision: D22048826

Pulled By: gg814

fbshipit-source-id: afdf8c11424a6f509b5c0b06dafad584a80103c9
2020-06-17 10:57:40 -07:00
Zhen Li
9c24a5cb4d Fix persistent cache on windows (#6932)
Summary:
Persistent cache feature caused rocks db crash on windows. I posted a issue for it, https://github.com/facebook/rocksdb/issues/6919. I found this is because no "persistent_cache_key_prefix" is generated for persistent cache. Looking repo history, "GetUniqueIdFromFile" is not implemented on Windows. So my fix is adding "NewId()" function in "persistent_cache" and using it to generate prefix for persistent cache. In this PR, i also re-enable related test cases defined in "db_test2" and "persistent_cache_test" for windows.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6932

Test Plan:
1. run related test cases in "db_test2" and "persistent_cache_test" on windows and see it passed.
2. manually run db_bench.exe with "read_cache_path" and verified.

Reviewed By: riversand963

Differential Revision: D21911608

Pulled By: cheng-chang

fbshipit-source-id: cdfd938d54a385edbb2836b13aaa1d39b0a6f1c2
2020-06-13 13:28:31 -07:00
Andrew Kryczka
e6be168aa5 save a key comparison in block seeks (#6646)
Summary:
This saves up to two key comparisons in block seeks. The first key
comparison saved is a redundant key comparison against the restart key
where the linear scan starts. This comparison is saved in all cases
except when the found key is in the first restart interval. The
second key comparison saved is a redundant key comparison against the
restart key where the linear scan ends. This is only saved in cases
where all keys in the restart interval are less than the target
(probability roughly `1/restart_interval`).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6646

Test Plan:
ran a benchmark with mostly default settings and counted key comparisons

before: `user_key_comparison_count = 19399529`
after: `user_key_comparison_count = 18431498`

setup command:

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

benchmark command:

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

Reviewed By: pdillinger

Differential Revision: D20849707

Pulled By: ajkr

fbshipit-source-id: 1f01c5cd99ea771fd27974046e37b194f1cdcfac
2020-06-10 13:58:39 -07:00
Andrew Kryczka
02db03af8d make L0 index/filter pinned memory usage predictable (#6911)
Summary:
Memory pinned by `pin_l0_filter_and_index_blocks_in_cache` needs to be predictable based on user config. This PR makes sure
we do not pin extra memory for large files generated by intra-L0 (see https://github.com/facebook/rocksdb/issues/6889).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6911

Test Plan: unit test

Reviewed By: siying

Differential Revision: D21835818

Pulled By: ajkr

fbshipit-source-id: a11a088549d06bed8aacc2548d266e5983f0ead4
2020-06-09 16:51:23 -07:00
Yanqin Jin
3020df9df5 Remove unnecessary inclusion of version_edit.h in env (#6952)
Summary:
In db_options.c, we should avoid including header files in the `db` directory to avoid introducing unnecessary dependency. The reason why `version_edit.h` has been included in `db_options.cc` is because we need two constants, `kUnknownChecksum` and `kUnknownChecksumFuncName`. We can put these two constants as `constexpr` in the public header `file_checksum.h`.

Test plan (devserver):
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6952

Reviewed By: zhichao-cao

Differential Revision: D21925341

Pulled By: riversand963

fbshipit-source-id: 2902f3b74c97f0cf16c58ad24c095c787c3a40e2
2020-06-07 21:56:55 -07:00
anand76
98b0cbea88 Check iterator status BlockBasedTableReader::VerifyChecksumInBlocks() (#6909)
Summary:
The ```for``` loop in ```VerifyChecksumInBlocks``` only checks ```index_iter->Valid()``` which could be ```false``` either due to reaching the end of the index or, in case of partitioned index, it could be due to a checksum mismatch error when reading a 2nd level index block. Instead of throwing away the index iterator status, we need to return any errors back to the caller.

Tests:
Add a test in block_based_table_reader_test.cc.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6909

Reviewed By: pdillinger

Differential Revision: D21833922

Pulled By: anand1976

fbshipit-source-id: bc778ebf1121dbbdd768689de5183f07a9f0beae
2020-06-05 11:08:25 -07:00
sdong
afa3518839 Revert "Update googletest from 1.8.1 to 1.10.0 (#6808)" (#6923)
Summary:
This reverts commit 8d87e9cea1.

Based on offline discussions, it's too early to upgrade to gtest 1.10, as it prevents some developers from using an older version of gtest to integrate to some other systems. Revert it for now.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6923

Reviewed By: pdillinger

Differential Revision: D21864799

fbshipit-source-id: d0726b1ff649fc911b9378f1763316200bd363fc
2020-06-03 15:55:03 -07:00
Peter Dillinger
9360776cb9 Fix handling of too-small filter partition size (#6905)
Summary:
Because ARM and some other platforms have a larger cache line
size, they have a larger minimum filter size, which causes recently
added PartitionedMultiGet test in db_bloom_filter_test to fail on those
platforms. The code would actually end up using larger partitions,
because keys_per_partition_ would be 0 and never == number of keys
added.

The code now attempts to get as close as possible to the small target
size, while fully utilizing that filter size, if the target partition
size is smaller than the minimum filter size.

Also updated the test to break more uniformly across platforms
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6905

Test Plan: updated test, tested on ARM

Reviewed By: anand1976

Differential Revision: D21840639

Pulled By: pdillinger

fbshipit-source-id: 11684b6d35f43d2e98b85ddb2c8dcfd59d670817
2020-06-03 10:43:01 -07:00
Peter Dillinger
14eca6bf04 For ApproximateSizes, pro-rate table metadata size over data blocks (#6784)
Summary:
The implementation of GetApproximateSizes was inconsistent in
its treatment of the size of non-data blocks of SST files, sometimes
including and sometimes now. This was at its worst with large portion
of table file used by filters and querying a small range that crossed
a table boundary: the size estimate would include large filter size.

It's conceivable that someone might want only to know the size in terms
of data blocks, but I believe that's unlikely enough to ignore for now.
Similarly, there's no evidence the internal function AppoximateOffsetOf
is used for anything other than a one-sided ApproximateSize, so I intend
to refactor to remove redundancy in a follow-up commit.

So to fix this, GetApproximateSizes (and implementation details
ApproximateSize and ApproximateOffsetOf) now consistently include in
their returned sizes a portion of table file metadata (incl filters
and indexes) based on the size portion of the data blocks in range. In
other words, if a key range covers data blocks that are X% by size of all
the table's data blocks, returned approximate size is X% of the total
file size. It would technically be more accurate to attribute metadata
based on number of keys, but that's not computationally efficient with
data available and rarely a meaningful difference.

Also includes miscellaneous comment improvements / clarifications.

Also included is a new approximatesizerandom benchmark for db_bench.
No significant performance difference seen with this change, whether ~700 ops/sec with cache_index_and_filter_blocks and small cache or ~150k ops/sec without cache_index_and_filter_blocks.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6784

Test Plan:
Test added to DBTest.ApproximateSizesFilesWithErrorMargin.
Old code running new test...

    [ RUN      ] DBTest.ApproximateSizesFilesWithErrorMargin
    db/db_test.cc:1562: Failure
    Expected: (size) <= (11 * 100), actual: 9478 vs 1100

Other tests updated to reflect consistent accounting of metadata.

Reviewed By: siying

Differential Revision: D21334706

Pulled By: pdillinger

fbshipit-source-id: 6f86870e45213334fedbe9c73b4ebb1d8d611185
2020-06-02 12:30:23 -07:00
sdong
298b00a396 Reduce dependency on gtest dependency in release code (#6907)
Summary:
Release code now depends on gtest, indirectly through including "test_util/testharness.h". This creates multiple problems. One important reason is the definition of IGNORE_STATUS_IF_ERROR() in test_util/testharness.h. Move it to sync_point.h instead.
Note that utilities/cassandra/format.h still depends on "test_util/testharness.h". This will be resolved in a separate diff.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6907

Test Plan: Run all existing tests.

Reviewed By: ajkr

Differential Revision: D21829884

fbshipit-source-id: 9253c19ffde2936f3ae68998210f8e54f645a6e6
2020-06-02 12:11:24 -07:00
Adam Retter
8d87e9cea1 Update googletest from 1.8.1 to 1.10.0 (#6808)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/6808

Reviewed By: anand1976

Differential Revision: D21483984

Pulled By: pdillinger

fbshipit-source-id: 70c5eff2bd54ddba469761d95e4cd4611fb8e598
2020-06-01 20:33:42 -07:00
anand76
66942e8158 Avoid unnecessary reads of uncompression dictionary in MultiGet (#6906)
Summary:
We may sometimes read the uncompression dictionary when its not
necessary, when we lookup a key in an SST file but the index indicates
the key is not present. This can happen with index_type 3.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6906

Test Plan: make check

Reviewed By: cheng-chang

Differential Revision: D21828944

Pulled By: anand1976

fbshipit-source-id: 7aef4f0a39548d0874eafefd2687006d2652f9bb
2020-06-01 19:43:37 -07:00
Cheng Chang
bcb9e41080 Explicitly free allocated buffer when status is not ok (#6903)
Summary:
Currently we rely on `BlockContents` to implicitly free the allocated scratch buffer, but when IO error happens, it doesn't make sense to construct the `BlockContents` which might be corrupted. In the stress test, we find that `assert(req.result.size() == block_size(handle));` fails because of potential IO errors.

In this PR, we explicitly free the scratch buffer on error without constructing `BlockContents`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6903

Test Plan: watch stress test

Reviewed By: anand1976

Differential Revision: D21823869

Pulled By: cheng-chang

fbshipit-source-id: 5603fc80e9bf3f44a9d7250ddebd871afe1eb89f
2020-06-01 15:19:40 -07:00
Andrew Kryczka
c5abf78bca avoid IterKey::UpdateInternalKey() in BlockIter (#6843)
Summary:
`IterKey::UpdateInternalKey()` is an error-prone API as it's
incompatible with `IterKey::TrimAppend()`, which is used for
decoding delta-encoded internal keys. This PR stops using it in
`BlockIter`. Instead, it assigns global seqno in a separate `IterKey`'s
buffer when needed. The logic for safely getting a Slice with global
seqno properly assigned is encapsulated in `GlobalSeqnoAppliedKey`.
`BinarySeek()` is also migrated to use this API (previously it ignored
global seqno entirely).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6843

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

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

benchmark run command:
```
TEST_TMPDIR=/dev/shm/$DB/ ./db_bench -benchmarks=seekrandom -seek_nexts=10 -use_existing_db=true -cache_index_and_filter_blocks=false -num=1000000 -cache_size=1048576000 -threads=1 -reads=40000000
```

results:

| DB | code | throughput |
|---|---|---|
| normal_db | master |  267.9 |
| normal_db   |    PR6843 | 254.2 (-5.1%) |
| ingestion_db |   master |  259.6 |
| ingestion_db |   PR6843 | 250.5 (-3.5%) |

Reviewed By: pdillinger

Differential Revision: D21562604

Pulled By: ajkr

fbshipit-source-id: 937596f836930515da8084d11755e1f247dcb264
2020-05-28 10:51:30 -07:00
Cheng Chang
82a82c76e7 Fix potential memory leak of scratch buffer (#6879)
Summary:
If `req.scratch` is an internally allocated buffer, but `raw_block_contents` is not constructed to own `req.scratch`, then `req.scratch` will be leaked.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6879

Test Plan: make asan_check

Reviewed By: anand1976

Differential Revision: D21728498

Pulled By: cheng-chang

fbshipit-source-id: 8fc6a4f2543918c565ddc16ecfad1807eb9a42cf
2020-05-26 15:29:04 -07:00
Andrew Kryczka
292bcf6227 skip direct I/O tests in rocksdb lite (#6867)
Summary:
Fix a couple places where direct I/O was used even though it is
unsupported in lite builds.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6867

Test Plan: `LITE=1 make check -j48`

Reviewed By: pdillinger

Differential Revision: D21689185

Pulled By: ajkr

fbshipit-source-id: 3eaa3abf69cd7d0bcaabbcad3bb5a26fb8dd7301
2020-05-21 13:57:17 -07:00
mrambacher
38be686160 Add Struct Type to OptionsTypeInfo (#6425)
Summary:
Added code for generically handing structs to OptionTypeInfo.  A struct is a collection of variables handled by their own map of OptionTypeInfos.  Examples of structs include Compaction and Cache options.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6425

Reviewed By: siying

Differential Revision: D21668789

Pulled By: zhichao-cao

fbshipit-source-id: 064b110de39dadf82361ed4663f7ac1a535b0b07
2020-05-21 10:58:39 -07:00
Cheng Chang
91b7553293 Enable IO Uring in MultiGet in direct IO mode (#6815)
Summary:
Currently, in direct IO mode, `MultiGet` retrieves the data blocks one by one instead of in parallel, see `BlockBasedTable::RetrieveMultipleBlocks`.

Since direct IO is supported in `RandomAccessFileReader::MultiRead` in https://github.com/facebook/rocksdb/pull/6446, this PR applies `MultiRead` to `MultiGet` so that the data blocks can be retrieved in parallel.

Also, in direct IO mode and when data blocks are compressed and need to uncompressed, this PR only allocates one continuous aligned buffer to hold the data blocks, and then directly uncompress the blocks to insert into block cache, there is no longer intermediate copies to scratch buffers.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6815

Test Plan:
1. added a new unit test `BlockBasedTableReaderTest::MultiGet`.
2. existing unit tests and stress tests  contain tests against `MultiGet` in direct IO mode.

Reviewed By: anand1976

Differential Revision: D21426347

Pulled By: cheng-chang

fbshipit-source-id: b8446ae0e74152444ef9111e97f8e402ac31b24f
2020-05-14 23:26:26 -07:00
sdong
4a4b8a1344 sst_dump to reduce number of file reads (#6836)
Summary:
sst_dump can issue many file reads from the file system. This doesn't work well with file systems without a OS cache, especially remote file systems. In order to mitigate this problem, several improvements are done:
1. --readahead_size is added, so that users can specify readahead size when scanning the data.
2. Force a 512KB tail readahead, which prevents three I/Os for footer, meta index and property blocks and hopefully index and filter blocks too.
3. Consoldiate SSTDump's I/Os before opening the file for read. Use the same file prefetch buffer.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6836

Test Plan: Add a test that covers this new feature.

Reviewed By: pdillinger

Differential Revision: D21516607

fbshipit-source-id: 3ae43526286f67b2f4a5bdedfbc92719d579b87e
2020-05-12 18:23:33 -07:00
Ziyue Yang
c384c08a4f Add tests for compression failure in BlockBasedTableBuilder (#6709)
Summary:
Currently there is no check for whether BlockBasedTableBuilder will expose
compression error status if compression fails during the table building.
This commit adds fake faulting compressors and a unit test to test such
cases.

This check finds 5 bugs, and this commit also fixes them:

1. Not handling compression failure well in
   BlockBasedTableBuilder::BGWorkWriteRawBlock.
2. verify_compression failing in BlockBasedTableBuilder when used with ZSTD.
3. Wrongly passing the same reference of block contents to
   BlockBasedTableBuilder::CompressAndVerifyBlock in parallel compression.
4. Wrongly setting block_rep->first_key_in_next_block to nullptr in
   BlockBasedTableBuilder::EnterUnbuffered when there are still incoming data
   blocks.
5. Not maintaining variables for compression ratio estimation and first_block
   in BlockBasedTableBuilder::EnterUnbuffered.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6709

Reviewed By: ajkr

Differential Revision: D21236254

fbshipit-source-id: 101f6e62b2bac2b7be72be198adf93cd32a1ff46
2020-05-12 09:27:35 -07:00
Peter Dillinger
b27a1448b6 Fix false NotFound from batched MultiGet with kHashSearch (#6821)
Summary:
The error is assigning KeyContext::s to NotFound status in a
table reader for a "not found in this table" case, which skips searching
in later tables, like only a delete should. (The hash search index iterator
is the only one that can return status NotFound even if Valid() == false.)

This was detected by intermittent failure in
MultiThreadedDBTest.MultiThreaded/5, a kHashSearch configuration.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6821

Test Plan: modified existing unit test to reproduce problem

Reviewed By: anand1976

Differential Revision: D21450469

Pulled By: pdillinger

fbshipit-source-id: 7478003684d637dbd491cdac81468041a791be2c
2020-05-07 15:41:37 -07:00
mrambacher
394f2bbd13 Add OptionTypeInfo::Enum and related methods (#6423)
Summary:
Add methods and constructors for handling enums to the OptionTypeInfo.  This change allows enums to be converted/compared without adding a special "type" to the OptionType.

This change addresses a couple of issues:
- It allows new enumerated types to be added to the options without editing the OptionType base class (and related methods)
- It standardizes the procedure for adding enumerated types to the options, reducing potential mistakes
- It moves the enum maps to the location where they are used, allowing them to be static file members rather than global values
- It reduces the number of types and cases that need to be handled in the various OptionType methods
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6423

Reviewed By: siying

Differential Revision: D21408713

Pulled By: zhichao-cao

fbshipit-source-id: fc492af285d011822578b95d186a0fce25d35626
2020-05-05 15:04:04 -07:00
sdong
079e50d2ba Disallow BlockBasedTableBuilder to set status from non-OK (#6776)
Summary:
There is no systematic mechanism to prevent BlockBasedTableBuilder's status to be set from non-OK to OK. Adding a mechanism to force this will help us prevent failures in the future.

The solution is to only make it possible to set the status code if the status code to set is not OK.

Since the status code passed to CompressAndVerifyBlock() is changed, a mini refactoring is done too so that the output arguments are changed from reference to pointers, based on Google C++ Style.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6776

Test Plan: Run all existing test.

Reviewed By: pdillinger

Differential Revision: D21314382

fbshipit-source-id: 27000c10f1e4c121661e026548d6882066409375
2020-04-30 15:37:03 -07:00
anand76
ab13d43e1d Pass a timeout to FileSystem for random reads (#6751)
Summary:
Calculate ```IOOptions::timeout``` using ```ReadOptions::deadline``` and pass it to ```FileSystem::Read/FileSystem::MultiRead```. This allows us to impose a tighter bound on the time taken by Get/MultiGet on FileSystem/Envs that support IO timeouts. Even on those that don't support, check in ```RandomAccessFileReader::Read``` and ```MultiRead``` and return ```Status::TimedOut()``` if the deadline is exceeded.

For now, TableReader creation, which might do file opens and reads, are not covered. It will be implemented in another PR.

Tests:
Update existing unit tests to verify the correct timeout value is being passed
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6751

Reviewed By: riversand963

Differential Revision: D21285631

Pulled By: anand1976

fbshipit-source-id: d89af843e5a91ece866e87aa29438b52a65a8567
2020-04-30 14:50:39 -07:00
mrambacher
618bf638aa Add Functions to OptionTypeInfo (#6422)
Summary:
Added functions for parsing, serializing, and comparing elements to OptionTypeInfo.  These functions allow all of the special cases that could not be handled directly in the map of OptionTypeInfo to be moved into the map.  Using these functions, every type can be handled via the map rather than special cased.

By adding these functions, the code for handling options can become more standardized (fewer special cases) and (eventually) handled completely by common classes.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6422

Test Plan: pass make check

Reviewed By: siying

Differential Revision: D21269005

Pulled By: zhichao-cao

fbshipit-source-id: 9ba71c721a38ebf9ee88259d60bd81b3282b9077
2020-04-28 18:04:26 -07:00
Peter Dillinger
bae6f58696 Basic MultiGet support for partitioned filters (#6757)
Summary:
In MultiGet, access each applicable filter partition only once
per batch, rather than for each applicable key. Also,

* Fix Bloom stats for MultiGet
* Fix/refactor MultiGetContext::Range::KeysLeft, including
* Add efficient BitsSetToOne implementation
* Assert that MultiGetContext::Range does not go beyond shift range

Performance test: Generate db:

    $ ./db_bench --benchmarks=fillrandom --num=15000000 --cache_index_and_filter_blocks -bloom_bits=10 -partition_index_and_filters=true
    ...

Before (middle performing run of three; note some missing Bloom stats):

    $ ./db_bench --use-existing-db --benchmarks=multireadrandom --num=15000000 --cache_index_and_filter_blocks --bloom_bits=10 --threads=16 --cache_size=20000000 -partition_index_and_filters -batch_size=32 -multiread_batched -statistics --duration=20 2>&1 | egrep 'micros/op|block.cache.filter.hit|bloom.filter.(full|use)|number.multiget'
    multireadrandom :      26.403 micros/op 597517 ops/sec; (548427 of 671968 found)
    rocksdb.block.cache.filter.hit COUNT : 83443275
    rocksdb.bloom.filter.useful COUNT : 0
    rocksdb.bloom.filter.full.positive COUNT : 0
    rocksdb.bloom.filter.full.true.positive COUNT : 7931450
    rocksdb.number.multiget.get COUNT : 385984
    rocksdb.number.multiget.keys.read COUNT : 12351488
    rocksdb.number.multiget.bytes.read COUNT : 793145000
    rocksdb.number.multiget.keys.found COUNT : 7931450

After (middle performing run of three):

    $ ./db_bench_new --use-existing-db --benchmarks=multireadrandom --num=15000000 --cache_index_and_filter_blocks --bloom_bits=10 --threads=16 --cache_size=20000000 -partition_index_and_filters -batch_size=32 -multiread_batched -statistics --duration=20 2>&1 | egrep 'micros/op|block.cache.filter.hit|bloom.filter.(full|use)|number.multiget'
    multireadrandom :      21.024 micros/op 752963 ops/sec; (705188 of 863968 found)
    rocksdb.block.cache.filter.hit COUNT : 49856682
    rocksdb.bloom.filter.useful COUNT : 45684579
    rocksdb.bloom.filter.full.positive COUNT : 10395458
    rocksdb.bloom.filter.full.true.positive COUNT : 9908456
    rocksdb.number.multiget.get COUNT : 481984
    rocksdb.number.multiget.keys.read COUNT : 15423488
    rocksdb.number.multiget.bytes.read COUNT : 990845600
    rocksdb.number.multiget.keys.found COUNT : 9908456

So that's about 25% higher throughput even for random keys
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6757

Test Plan: unit test included

Reviewed By: anand1976

Differential Revision: D21243256

Pulled By: pdillinger

fbshipit-source-id: 5644a1468d9e8c8575be02f4e04bc5d62dbbb57f
2020-04-28 14:49:34 -07:00
Peter Dillinger
249eff0f30 Stats for redundant insertions into block cache (#6681)
Summary:
Since read threads do not coordinate on loading data into block
cache, two threads between Lookup and Insert can end up loading and
inserting the same data. This is particularly concerning with
cache_index_and_filter_blocks since those are hot and more likely to
be race targets if ejected from (or not pre-populated in) the cache.

Particularly with moves toward disaggregated / network storage, the cost
of redundant retrieval might be high, and we should at least have some
hard statistics from which we can estimate impact.

Example with full filter thrashing "cliff":

    $ ./db_bench --benchmarks=fillrandom --num=15000000 --cache_index_and_filter_blocks -bloom_bits=10
    ...
    $ ./db_bench --db=/tmp/rocksdbtest-172704/dbbench --use_existing_db --benchmarks=readrandom,stats --num=200000 --cache_index_and_filter_blocks --cache_size=$((130 * 1024 * 1024)) --bloom_bits=10 --threads=16 -statistics 2>&1 | egrep '^rocksdb.block.cache.(.*add|.*redundant)' | grep -v compress | sort
    rocksdb.block.cache.add COUNT : 14181
    rocksdb.block.cache.add.failures COUNT : 0
    rocksdb.block.cache.add.redundant COUNT : 476
    rocksdb.block.cache.data.add COUNT : 12749
    rocksdb.block.cache.data.add.redundant COUNT : 18
    rocksdb.block.cache.filter.add COUNT : 1003
    rocksdb.block.cache.filter.add.redundant COUNT : 217
    rocksdb.block.cache.index.add COUNT : 429
    rocksdb.block.cache.index.add.redundant COUNT : 241
    $ ./db_bench --db=/tmp/rocksdbtest-172704/dbbench --use_existing_db --benchmarks=readrandom,stats --num=200000 --cache_index_and_filter_blocks --cache_size=$((120 * 1024 * 1024)) --bloom_bits=10 --threads=16 -statistics 2>&1 | egrep '^rocksdb.block.cache.(.*add|.*redundant)' | grep -v compress | sort
    rocksdb.block.cache.add COUNT : 1182223
    rocksdb.block.cache.add.failures COUNT : 0
    rocksdb.block.cache.add.redundant COUNT : 302728
    rocksdb.block.cache.data.add COUNT : 31425
    rocksdb.block.cache.data.add.redundant COUNT : 12
    rocksdb.block.cache.filter.add COUNT : 795455
    rocksdb.block.cache.filter.add.redundant COUNT : 130238
    rocksdb.block.cache.index.add COUNT : 355343
    rocksdb.block.cache.index.add.redundant COUNT : 172478
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6681

Test Plan: Some manual testing (above) and unit test covering key metrics is included

Reviewed By: ltamasi

Differential Revision: D21134113

Pulled By: pdillinger

fbshipit-source-id: c11497b5f00f4ffdfe919823904e52d0a1a91d87
2020-04-27 13:20:27 -07:00
anand76
9e7b7e2c08 Silence false alarms in db_stress fault injection (#6741)
Summary:
False alarms are caused by codepaths that intentionally swallow IO
errors.

Tests:
make crash_test
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6741

Reviewed By: ltamasi

Differential Revision: D21181138

Pulled By: anand1976

fbshipit-source-id: 5ccfbc68eb192033488de6269e59c00f2c65ce00
2020-04-24 13:06:12 -07:00
Ibrahim Jarif
ae77880223 Fix some typos in code comments (#6733)
Summary:
This PR fixes some typos in code comments.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6733

Reviewed By: siying

Differential Revision: D21209037

Pulled By: zhichao-cao

fbshipit-source-id: d9274611fab1f5e992998c8c4117b8078c4cbc69
2020-04-23 12:28:49 -07:00
mrambacher
4cbc19d2a1 Add a ConfigOptions for use in comparing objects and converting to/from strings (#6389)
Summary:
The methods in convenience.h are used to compare/convert objects to/from strings.  There is a mishmash of parameters in use here with more needed in the future.  This PR replaces those parameters with a single structure.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6389

Reviewed By: siying

Differential Revision: D21163707

Pulled By: zhichao-cao

fbshipit-source-id: f807b4cc7e2b0af3871536b69546b2604dfa81bd
2020-04-21 17:38:17 -07:00
Andrew Kryczka
f9155a3404 Prevent uninitialized load in IndexBlockIter (#6736)
Summary:
When index block is empty or an error happens while reading it,
`Invalidate()` is called rather than `Initialize()`. So `Seek()` must
not refer to member variables that are only initialized in
`Initialize()` until it is sure `Initialize()` has been called.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6736

Reviewed By: siying

Differential Revision: D21139641

Pulled By: ajkr

fbshipit-source-id: 71c58cc1adbd795dc3729dd5023bf7df1515ff32
2020-04-20 16:32:43 -07:00
Peter Dillinger
31da5e34c1 C++20 compatibility (#6697)
Summary:
Based on https://github.com/facebook/rocksdb/issues/6648 (CLA Signed), but heavily modified / extended:

* Implicit capture of this via [=] deprecated in C++20, and [=,this] not standard before C++20 -> now using explicit capture lists
* Implicit copy operator deprecated in gcc 9 -> add explicit '= default' definition
* std::random_shuffle deprecated in C++17 and removed in C++20 -> migrated to a replacement in RocksDB random.h API
* Add the ability to build with different std version though -DCMAKE_CXX_STANDARD=11/14/17/20 on the cmake command line
* Minimal rebuild flag of MSVC is deprecated and is forbidden with /std:c++latest (C++20)
* Added MSVC 2019 C++11 & MSVC 2019 C++20 in AppVeyor
* Added GCC 9 C++11 & GCC9 C++20 in Travis
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6697

Test Plan: make check and CI

Reviewed By: cheng-chang

Differential Revision: D21020318

Pulled By: pdillinger

fbshipit-source-id: 12311be5dbd8675a0e2c817f7ec50fa11c18ab91
2020-04-20 13:24:25 -07:00
Mike Kolupaev
e45673dece Properly report IO errors when IndexType::kBinarySearchWithFirstKey is used (#6621)
Summary:
Context: Index type `kBinarySearchWithFirstKey` added the ability for sst file iterator to sometimes report a key from index without reading the corresponding data block. This is useful when sst blocks are cut at some meaningful boundaries (e.g. one block per key prefix), and many seeks land between blocks (e.g. for each prefix, the ranges of keys in different sst files are nearly disjoint, so a typical seek needs to read a data block from only one file even if all files have the prefix). But this added a new error condition, which rocksdb code was really not equipped to deal with: `InternalIterator::value()` may fail with an IO error or Status::Incomplete, but it's just a method returning a Slice, with no way to report error instead. Before this PR, this type of error wasn't handled at all (an empty slice was returned), and kBinarySearchWithFirstKey implementation was considered a prototype.

Now that we (LogDevice) have experimented with kBinarySearchWithFirstKey for a while and confirmed that it's really useful, this PR is adding the missing error handling.

It's a pretty inconvenient situation implementation-wise. The error needs to be reported from InternalIterator when trying to access value. But there are ~700 call sites of `InternalIterator::value()`, most of which either can't hit the error condition (because the iterator is reading from memtable or from index or something) or wouldn't benefit from the deferred loading of the value (e.g. compaction iterator that reads all values anyway). Adding error handling to all these call sites would needlessly bloat the code. So instead I made the deferred value loading optional: only the call sites that may use deferred loading have to call the new method `PrepareValue()` before calling `value()`. The feature is enabled with a new bool argument `allow_unprepared_value` to a bunch of methods that create iterators (it wouldn't make sense to put it in ReadOptions because it's completely internal to iterators, with virtually no user-visible effect). Lmk if you have better ideas.

Note that the deferred value loading only happens for *internal* iterators. The user-visible iterator (DBIter) always prepares the value before returning from Seek/Next/etc. We could go further and add an API to defer that value loading too, but that's most likely not useful for LogDevice, so it doesn't seem worth the complexity for now.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6621

Test Plan: make -j5 check . Will also deploy to some logdevice test clusters and look at stats.

Reviewed By: siying

Differential Revision: D20786930

Pulled By: al13n321

fbshipit-source-id: 6da77d918bad3780522e918f17f4d5513d3e99ee
2020-04-15 17:40:44 -07:00
Ziyue Yang
41563b61db Fix data racing of BlockBasedTableBuilder::ParallelCompressionRep::first_block (#6640)
Summary:
BlockBasedTableBuilder::ParallelCompressionRep::first_block can be read in
Flush() and written in BGWorkWriteRawBlock() concurrently. This commit fixes
the issue by reading first_block out before pushing the block to compression
and write.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6640

Test Plan: Run all tests concurrently with TSAN.

Reviewed By: cheng-chang

Differential Revision: D20851370

fbshipit-source-id: 6f039222e8319d31e15f1b45e05c106527253f72
2020-04-13 16:24:57 -07:00
Andrew Kryczka
9eca6d651d fix comparison count for format_version=3 indexes (#6650)
Summary:
In index blocks since `format_version=3`, user keys are written
rather than internal keys. When reading such blocks, the comparator is
obtained via `InternalKeyComparator::user_comparator()`. That function
must not return an unwrapped result as the wrapper class provides
accounting logic to populate `PerfContext::user_key_comparison_count`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6650

Test Plan:
ran db_bench and verified
`PerfContext::user_key_comparison_count` became larger.

Reviewed By: cheng-chang

Differential Revision: D20866325

Pulled By: ajkr

fbshipit-source-id: ad755d46bda31157dacc5b66e532279f19ad538c
2020-04-13 11:18:37 -07:00