Commit Graph

257 Commits

Author SHA1 Message Date
Peter Dillinger fc3a6eb74a Fix/improve 'must free heap allocations' code (#9209)
Summary:
Added missing include, and cleaned up to make same mistake less
likely in future (minimize conditional compilation)

Fixes https://github.com/facebook/rocksdb/issues/9183

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9209

Test Plan: added to existing test

Reviewed By: mrambacher

Differential Revision: D32631390

Pulled By: pdillinger

fbshipit-source-id: 63a0501855cf5fac9e22ca1e5c4f53725dbf3f93
2021-11-29 10:53:52 -08:00
Hui Xiao 74544d582f Account Bloom/Ribbon filter construction memory in global memory limit (#9073)
Summary:
Note: This PR is the 4th part of a bigger PR stack (https://github.com/facebook/rocksdb/pull/9073) and will rebase/merge only after the first three PRs (https://github.com/facebook/rocksdb/pull/9070, https://github.com/facebook/rocksdb/pull/9071, https://github.com/facebook/rocksdb/pull/9130) merge.

**Context:**
Similar to https://github.com/facebook/rocksdb/pull/8428, this PR is to track memory usage during (new) Bloom Filter (i.e,FastLocalBloom) and Ribbon Filter (i.e, Ribbon128) construction, moving toward the goal of [single global memory limit using block cache capacity](https://github.com/facebook/rocksdb/wiki/Projects-Being-Developed#improving-memory-efficiency). It also constrains the size of the banding portion of Ribbon Filter during construction by falling back to Bloom Filter if that banding is, at some point, larger than the available space in the cache under `LRUCacheOptions::strict_capacity_limit=true`.

The option to turn on this feature is `BlockBasedTableOptions::reserve_table_builder_memory = true` which by default is set to `false`. We [decided](https://github.com/facebook/rocksdb/pull/9073#discussion_r741548409) not to have separate option for separate memory user in table building therefore their memory accounting are all bundled under one general option.

**Summary:**
- Reserved/released cache for creation/destruction of three main memory users with the passed-in `FilterBuildingContext::cache_res_mgr` during filter construction:
   - hash entries (i.e`hash_entries`.size(), we bucket-charge hash entries during insertion for performance),
   - banding (Ribbon Filter only, `bytes_coeff_rows` +`bytes_result_rows` + `bytes_backtrack`),
   - final filter (i.e, `mutable_buf`'s size).
      - Implementation details: in order to use `CacheReservationManager::CacheReservationHandle` to account final filter's memory, we have to store the `CacheReservationManager` object and `CacheReservationHandle` for final filter in `XXPH3BitsFilterBuilder` as well as  explicitly delete the filter bits builder when done with the final filter in block based table.
- Added option fo run `filter_bench` with this memory reservation feature

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9073

Test Plan:
- Added new tests in `db_bloom_filter_test` to verify filter construction peak cache reservation under combination of  `BlockBasedTable::Rep::FilterType` (e.g, `kFullFilter`, `kPartitionedFilter`), `BloomFilterPolicy::Mode`(e.g, `kFastLocalBloom`, `kStandard128Ribbon`, `kDeprecatedBlock`) and `BlockBasedTableOptions::reserve_table_builder_memory`
  - To address the concern for slow test: tests with memory reservation under `kFullFilter` + `kStandard128Ribbon` and `kPartitionedFilter` take around **3000 - 6000 ms** and others take around **1500 - 2000 ms**, in total adding **20000 - 25000 ms** to the test suit running locally
- Added new test in `bloom_test` to verify Ribbon Filter fallback on large banding in FullFilter
- Added test in `filter_bench` to verify that this feature does not significantly slow down Bloom/Ribbon Filter construction speed. Local result averaged over **20** run as below:
   - FastLocalBloom
      - baseline `./filter_bench -impl=2 -quick -runs 20 | grep 'Build avg'`:
         - **Build avg ns/key: 29.56295** (DEBUG_LEVEL=1), **29.98153** (DEBUG_LEVEL=0)
      - new feature (expected to be similar as above)`./filter_bench -impl=2 -quick -runs 20 -reserve_table_builder_memory=true | grep 'Build avg'`:
         - **Build avg ns/key: 30.99046** (DEBUG_LEVEL=1), **30.48867** (DEBUG_LEVEL=0)
      - new feature of RibbonFilter with fallback  (expected to be similar as above) `./filter_bench -impl=2 -quick -runs 20 -reserve_table_builder_memory=true -strict_capacity_limit=true | grep 'Build avg'` :
         - **Build avg ns/key: 31.146975** (DEBUG_LEVEL=1), **30.08165** (DEBUG_LEVEL=0)

    - Ribbon128
       - baseline `./filter_bench -impl=3 -quick -runs 20 | grep 'Build avg'`:
           - **Build avg ns/key: 129.17585** (DEBUG_LEVEL=1), **130.5225** (DEBUG_LEVEL=0)
       - new feature  (expected to be similar as above) `./filter_bench -impl=3 -quick -runs 20 -reserve_table_builder_memory=true | grep 'Build avg' `:
           - **Build avg ns/key: 131.61645** (DEBUG_LEVEL=1), **132.98075** (DEBUG_LEVEL=0)
       - new feature of RibbonFilter with fallback (expected to be a lot faster than above due to fallback) `./filter_bench -impl=3 -quick -runs 20 -reserve_table_builder_memory=true -strict_capacity_limit=true | grep 'Build avg'` :
          - **Build avg ns/key: 52.032965** (DEBUG_LEVEL=1), **52.597825** (DEBUG_LEVEL=0)
          - And the warning message of `"Cache reservation for Ribbon filter banding failed due to cache full"` is indeed logged to console.

Reviewed By: pdillinger

Differential Revision: D31991348

Pulled By: hx235

fbshipit-source-id: 9336b2c60f44d530063da518ceaf56dac5f9df8e
2021-11-18 09:42:20 -08:00
Peter Dillinger f8c685c4fc Check for and disallow shared key space in block caches (#9172)
Summary:
We have three layers of block cache that often use the same key
but map to different physical data:
* BlockBasedTableOptions::block_cache
* BlockBasedTableOptions::block_cache_compressed
* BlockBasedTableOptions::persistent_cache

If any two of these happen to share an underlying implementation and key
space (insertion into one shows up in another), then memory safety is
broken. The simplest case is block_cache == block_cache_compressed.
(Credit mrambacher for asking about this case in a review.)

With this change, we explicitly check for overlap and preemptively and
safely fail with a Status code.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9172

Test Plan: test added. Crashes without new check

Reviewed By: anand1976

Differential Revision: D32465659

Pulled By: pdillinger

fbshipit-source-id: 3876b45b6dce6167e5a7a642725ddc86b96f8e40
2021-11-16 11:16:05 -08:00
Hui Xiao 2fbe32b0c1 RAII support for per cache reservation through handle (#9130)
Summary:
Note: This PR is the 3rd PR of a bigger PR stack (https://github.com/facebook/rocksdb/issues/9073) and depends on the second PR (https://github.com/facebook/rocksdb/pull/9071). **See changes from this PR only 00447324d0**

Context:
pdillinger brought up a good [point](https://github.com/facebook/rocksdb/pull/9073#discussion_r741478309) about lacking RAII support for per cache reservation in `CacheReservationManager`  when reviewing https://github.com/facebook/rocksdb/pull/9073.

To summarize the discussion, the current API `CacheReservationManager::UpdateCacheReservation()` requires callers to explicitly calculate and pass in a correct`new_mem_used` to release a cache reservation (if they don't want to rely on the clean-up during `CacheReservationManager`'s destruction - such as they want to release it earlier).

While this implementation has convenience in some use-case such as `WriteBufferManager`, where [reservation](https://github.com/facebook/rocksdb/blob/main/memtable/write_buffer_manager.cc#L69-L91) and [release](https://github.com/facebook/rocksdb/blob/main/memtable/write_buffer_manager.cc#L109-L129) amounts do not necessarily correspond symmetrically and thus a flexible `new_mem_used` inputing is needed, it can be prone to caller's calculation error as well as cause a mass of codes in releasing cache in other use-case such as filter construction, where reservation and release amounts do correspond symmetrically and many code paths requiring a cache release, as [pointed](https://github.com/facebook/rocksdb/pull/9073#discussion_r741478309) out by pdillinger.

Therefore we decided to provide a new API in `CacheReservationManager` to update reservation with better RAII support for per cache reservation, using a handle to manage the life time of that particular cache reservation.
- Added a new class `CacheReservationHandle`
- Added a new API `CacheReservationManager::MakeCacheReservation()` that outputs a `CacheReservationHandle` for managing the reservation
- Updated class comments to clarify two different cache reservation methods

Tests:
- Passing new tests

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9130

Reviewed By: pdillinger

Differential Revision: D32199446

Pulled By: hx235

fbshipit-source-id: 1cba7c636e5ecfb55b0c1e0c2d218cc9b5b30b4e
2021-11-09 12:06:28 -08:00
Hui Xiao ffd6085e1f Add new API CacheReservationManager::GetTotalMemoryUsage() (#9071)
Summary:
Note: This PR is the 2nd PR of a bigger PR stack (https://github.com/facebook/rocksdb/pull/9073).

Context:
`CacheReservationManager::UpdateCacheReservation(std::size_t new_memory_used)` accepts an accumulated total memory used (e.g, used 10MB so far) instead of usage change (e.g, increase by 5 MB, decrease by 5 MB). It has benefits including consolidating API for increase and decrease as described in https://github.com/facebook/rocksdb/pull/8506.

However, not every `CacheReservationManager` user keeps track of this accumulated total memory usage. For example, Bloom/Ribbon Filter construction (e.g, [here](822d729fcd/table/block_based/filter_policy.cc (L587)) in https://github.com/facebook/rocksdb/pull/9073) does not  while WriteBufferManager and compression dictionary buffering do.

Considering future users might or might not keep track of this counter and implementing this counter within `CacheReservationManager` is easy due to the passed-in `std::size_t new_memory_used` in calling `CacheReservationManager::UpdateCacheReservation(std::size_t new_memory_used)`, it is proposed to add a new API `CacheReservationManager::GetTotalMemoryUsage()`.

As noted in the API comments,   since `CacheReservationManager` is NOT thread-safe, external synchronization is
 needed in calling `UpdateCacheReservation()` if you want `GetTotalMemoryUsed()` returns the indeed latest memory used.
- Added and updated private counter `memory_used_` every time `CacheReservationManager::UpdateCacheReservation(std::size_t new_memory_used)` is called regardless if the call returns non-okay status
- Added `CacheReservationManager::GetTotalMemoryUsage()` to return `memory_used_`

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9071

Test Plan:
- Passing new tests
- Passing existing tests

Reviewed By: ajkr

Differential Revision: D31887813

Pulled By: hx235

fbshipit-source-id: 9a09f0c8683822673260362894c878b61ee60ceb
2021-11-09 08:17:03 -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 560fe70233 Add new API CacheReservationManager::GetDummyEntrySize() (#9072)
Summary:
Note: it might conflict with another CRM related PR https://github.com/facebook/rocksdb/pull/9071 and so will merge after that's merged.

Context:
As `CacheReservationManager` being used by more memory users, it is convenient to retrieve the dummy entry size for `CacheReservationManager` instead of hard-coding `256 * 1024` in writing tests. Plus it allows more flexibility to change our implementation on dummy entry size.

A follow-up PR is needed to replace those hard-coded dummy entry size value in `db_test2.cc`, `db_write_buffer_manager_test.cc`, `write_buffer_manager_test.cc`, `table_test.cc` and the ones introduced in https://github.com/facebook/rocksdb/pull/9072#issue-1034326069.
- Exposed the private static constexpr `kDummyEntrySize` through public static `CacheReservationManager::GetDummyEntrySize()`

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9072

Test Plan:
- Passing new tests
- Passing existing tests

Reviewed By: ajkr

Differential Revision: D32043684

Pulled By: hx235

fbshipit-source-id: ddefc6921c052adab6a2cda2394eb26da3076a50
2021-11-01 14:46:09 -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
Zhichao Cao 699f45049d Introduce a mechanism to dump out blocks from block cache and re-insert to secondary cache (#8912)
Summary:
Background: Cache warming up will cause potential read performance degradation due to reading blocks from storage to the block cache. Since in production, the workload and access pattern to a certain DB is stable, it is a potential solution to dump out the blocks belonging to a certain DB to persist storage (e.g., to a file) and bulk-load the blocks to Secondary cache before the DB is relaunched. For example, when migrating a DB form host A to host B, it will take a short period of time, the access pattern to blocks in the block cache will not change much. It is efficient to dump out the blocks of certain DB, migrate to the destination host and insert them to the Secondary cache before we relaunch the DB.

Design: we introduce the interface of CacheDumpWriter and CacheDumpRead for user to store the blocks dumped out from block cache. RocksDB will encode all the information and send the string to the writer. User can implement their own writer it they want. CacheDumper and CacheLoad are introduced to save the blocks and load the blocks respectively.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8912

Test Plan: add new tests to lru_cache_test and pass make check.

Reviewed By: pdillinger

Differential Revision: D31452871

Pulled By: zhichao-cao

fbshipit-source-id: 11ab4f5d03e383f476947116361d54188d36ec48
2021-10-07 11:42:31 -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
Hui Xiao 0aad4ca0ff Add comment for new_memory_used parameter in CacheReservationManager::UpdateCacheReservation (#8895)
Summary:
Context/Summary: this PR is to clarify what the parameter new_memory_used is in CacheReservationManager::UpdateCacheReservation

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8895

Test Plan:
- Passing existing test
- Make format

Reviewed By: jay-zhuang

Differential Revision: D30844814

Pulled By: hx235

fbshipit-source-id: 3177f7abf5668ea9e73818ceaa355566f03acabc
2021-09-09 15:25:24 -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
anand76 ec9f52ece6 Fix a race in LRUCacheShard::Promote (#8717)
Summary:
In ```LRUCacheShard::Promote```, a reference is released outside the LRU mutex. Fix the race condition.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8717

Reviewed By: zhichao-cao

Differential Revision: D30649206

Pulled By: anand1976

fbshipit-source-id: 09c0af05b2294a7fe2c02876a61b0bad6e3ada61
2021-08-30 19:10:55 -07:00
Hui Xiao 74cfe7db60 Refactor WriteBufferManager::CacheRep into CacheReservationManager (#8506)
Summary:
Context:
To help cap various memory usage by a single limit of the block cache capacity, we charge the memory usage through inserting/releasing dummy entries in the block cache. CacheReservationManager is such a class (non thread-safe) responsible for  inserting/removing dummy entries to reserve cache space for memory used by the class user.

- Refactored the inner private class CacheRep of WriteBufferManager into public CacheReservationManager class for reusability such as for https://github.com/facebook/rocksdb/pull/8428

- Encapsulated implementation details of cache key generation and dummy entries insertion/release in cache reservation as discussed in https://github.com/facebook/rocksdb/pull/8506#discussion_r666550838

- Consolidated increase/decrease cache reservation into one API - UpdateCacheReservation.

- Adjusted the previous dummy entry release algorithm in decreasing cache reservation to be loop-releasing dummy entries to stay symmetric to dummy entry insertion algorithm

- Made the previous dummy entry release algorithm in delayed decrease mode more aggressive for better decreasing cache reservation when memory used is less likely to increase back.

  Previously, the algorithms only release 1 dummy entries when new_mem_used < 3/4 * cache_allocated_size_ and cache_allocated_size_ - kSizeDummyEntry > new_mem_used.
Now, the algorithms loop-releases as many dummy entries as possible when new_mem_used < 3/4 * cache_allocated_size_.

- Updated WriteBufferManager's test cases to adapt to changes on the release algorithm mentioned above and left comment for some test cases for clarity

- Replaced the previous cache key prefix generation (utilizing object address related to the cache client) with one that utilizes Cache->NewID() to prevent cache-key collision among dummy entry clients sharing the same cache.

  The specific collision we are preventing happens when the object address is reused for a new cache-key prefix while the old cache-key using that same object address in its prefix still exists in the cache. This could happen due to that, under LRU cache policy, there is a possible delay in releasing a cache entry after the cache client object owning that cache entry get deallocated. In this case, the object address related to the cache client object can get reused for other client object to generate a new cache-key prefix.

  This prefix generation can be made obsolete after Peter's unification of all the code generating cache key, mentioned in https://github.com/facebook/rocksdb/pull/8506#discussion_r667265255

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8506

Test Plan:
- Passing the added unit tests cache_reservation_manager_test.cc
- Passing existing and adjusted write_buffer_manager_test.cc

Reviewed By: ajkr

Differential Revision: D29644135

Pulled By: hx235

fbshipit-source-id: 0fc93fbfe4a40bb41be85c314f8f2bafa8b741f7
2021-08-24 12:43:31 -07:00
anand76 f35042ca40 Add a PerfContext counter for secondary cache hits (#8685)
Summary:
Add a PerfContext counter.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8685

Reviewed By: zhichao-cao

Differential Revision: D30453957

Pulled By: anand1976

fbshipit-source-id: 42888a3ced240e1c44446d52d3b04adfb01f5665
2021-08-20 15:17:30 -07:00
anand76 add68bd28a Add a stat to count secondary cache hits (#8666)
Summary:
Add a stat for secondary cache hits. The ```Cache::Lookup``` API had an unused ```stats``` parameter. This PR uses that to pass the pointer to a ```Statistics``` object that ```LRUCache``` uses to record the stat.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8666

Test Plan: Update a unit test in lru_cache_test

Reviewed By: zhichao-cao

Differential Revision: D30353816

Pulled By: anand1976

fbshipit-source-id: 2046f78b460428877a26ffdd2bb914ae47dfbe77
2021-08-16 21:01:14 -07:00
Drewryz 3b27725245 Fix a minor issue with initializing the test path (#8555)
Summary:
The PerThreadDBPath has already specified a slash. It does not need to be specified when initializing the test path.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8555

Reviewed By: ajkr

Differential Revision: D29758399

Pulled By: jay-zhuang

fbshipit-source-id: 6d2b878523e3e8580536e2829cb25489844d9011
2021-07-23 08:38:45 -07:00
Peter Dillinger df5dc73bec Don't hold DB mutex for block cache entry stat scans (#8538)
Summary:
I previously didn't notice the DB mutex was being held during
block cache entry stat scans, probably because I primarily checked for
read performance regressions, because they require the block cache and
are traditionally latency-sensitive.

This change does some refactoring to avoid holding DB mutex and to
avoid triggering and waiting for a scan in GetProperty("rocksdb.cfstats").
Some tests have to be updated because now the stats collector is
populated in the Cache aggressively on DB startup rather than lazily.
(I hope to clean up some of this added complexity in the future.)

This change also ensures proper treatment of need_out_of_mutex for
non-int DB properties.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8538

Test Plan:
Added unit test logic that uses sync points to fail if the DB mutex
is held during a scan, covering the various ways that a scan might be
triggered.

Performance test - the known impact to holding the DB mutex is on
TransactionDB, and the easiest way to see the impact is to hack the
scan code to almost always miss and take an artificially long time
scanning. Here I've injected an unconditional 5s sleep at the call to
ApplyToAllEntries.

Before (hacked):

    $ TEST_TMPDIR=/dev/shm ./db_bench.base_xxx -benchmarks=randomtransaction,stats -cache_index_and_filter_blocks=1 -bloom_bits=10 -partition_index_and_filters=1 -duration=30 -stats_dump_period_sec=12 -cache_size=100000000 -statistics -transaction_db 2>&1 | egrep 'db.db.write.micros|micros/op'
    randomtransaction :     433.219 micros/op 2308 ops/sec;    0.1 MB/s ( transactions:78999 aborts:0)
    rocksdb.db.write.micros P50 : 16.135883 P95 : 36.622503 P99 : 66.036115 P100 : 5000614.000000 COUNT : 149677 SUM : 8364856
    $ TEST_TMPDIR=/dev/shm ./db_bench.base_xxx -benchmarks=randomtransaction,stats -cache_index_and_filter_blocks=1 -bloom_bits=10 -partition_index_and_filters=1 -duration=30 -stats_dump_period_sec=12 -cache_size=100000000 -statistics -transaction_db 2>&1 | egrep 'db.db.write.micros|micros/op'
    randomtransaction :     448.802 micros/op 2228 ops/sec;    0.1 MB/s ( transactions:75999 aborts:0)
    rocksdb.db.write.micros P50 : 16.629221 P95 : 37.320607 P99 : 72.144341 P100 : 5000871.000000 COUNT : 143995 SUM : 13472323

Notice the 5s P100 write time.

After (hacked):

    $ TEST_TMPDIR=/dev/shm ./db_bench.new_xxx -benchmarks=randomtransaction,stats -cache_index_and_filter_blocks=1 -bloom_bits=10 -partition_index_and_filters=1 -duration=30 -stats_dump_period_sec=12 -cache_size=100000000 -statistics -transaction_db 2>&1 | egrep 'db.db.write.micros|micros/op'
    randomtransaction :     303.645 micros/op 3293 ops/sec;    0.1 MB/s ( transactions:98999 aborts:0)
    rocksdb.db.write.micros P50 : 16.061871 P95 : 33.978834 P99 : 60.018017 P100 : 616315.000000 COUNT : 187619 SUM : 4097407
    $ TEST_TMPDIR=/dev/shm ./db_bench.new_xxx -benchmarks=randomtransaction,stats -cache_index_and_filter_blocks=1 -bloom_bits=10 -partition_index_and_filters=1 -duration=30 -stats_dump_period_sec=12 -cache_size=100000000 -statistics -transaction_db 2>&1 | egrep 'db.db.write.micros|micros/op'
    randomtransaction :     310.383 micros/op 3221 ops/sec;    0.1 MB/s ( transactions:96999 aborts:0)
    rocksdb.db.write.micros P50 : 16.270026 P95 : 35.786844 P99 : 64.302878 P100 : 603088.000000 COUNT : 183819 SUM : 4095918

P100 write is now ~0.6s. Not good, but it's the same even if I completely bypass all the scanning code:

    $ TEST_TMPDIR=/dev/shm ./db_bench.new_skip -benchmarks=randomtransaction,stats -cache_index_and_filter_blocks=1 -bloom_bits=10 -partition_index_and_filters=1 -duration=30 -stats_dump_period_sec=12 -cache_size=100000000 -statistics -transaction_db 2>&1 | egrep 'db.db.write.micros|micros/op'
    randomtransaction :     311.365 micros/op 3211 ops/sec;    0.1 MB/s ( transactions:96999 aborts:0)
    rocksdb.db.write.micros P50 : 16.274362 P95 : 36.221184 P99 : 68.809783 P100 : 649808.000000 COUNT : 183819 SUM : 4156767
    $ TEST_TMPDIR=/dev/shm ./db_bench.new_skip -benchmarks=randomtransaction,stats -cache_index_and_filter_blocks=1 -bloom_bits=10 -partition_index_and_filters=1 -duration=30 -stats_dump_period_sec=12 -cache_size=100000000 -statistics -transaction_db 2>&1 | egrep 'db.db.write.micros|micros/op'
    randomtransaction :     308.395 micros/op 3242 ops/sec;    0.1 MB/s ( transactions:97999 aborts:0)
    rocksdb.db.write.micros P50 : 16.106222 P95 : 37.202403 P99 : 67.081875 P100 : 598091.000000 COUNT : 185714 SUM : 4098832

No substantial difference.

Reviewed By: siying

Differential Revision: D29738847

Pulled By: pdillinger

fbshipit-source-id: 1c5c155f5a1b62e4fea0fd4eeb515a8b7474027b
2021-07-16 14:13:08 -07:00
Peter Dillinger 5ad3227650 Work around falsely reported data race on LRUHandle::flags (#8539)
Summary:
Some bits are mutated and read while holding a lock, other
immutable bits (esp. secondary cache compatibility) can be read by
arbitrary threads without holding a lock. AFAIK, this doesn't cause an
issue on any architecture we care about, because you will get some
legitimate version of the value that includes the initialization, as
long as synchronization guarantees the initialization happens before the
read.

I've only seen this in https://github.com/facebook/rocksdb/issues/8538 so far, but it should be fixed regardless.
Otherwise, we'll surely get these false reports again some time.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8539

Test Plan: some local TSAN test runs and in CircleCI

Reviewed By: zhichao-cao

Differential Revision: D29720262

Pulled By: pdillinger

fbshipit-source-id: 365fd7e565577c648815161f71b339bcb5ce12d5
2021-07-15 16:09:18 -07:00
mrambacher 570248aeff Make SecondaryCache Customizable (#8480)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8480

Reviewed By: zhichao-cao

Differential Revision: D29528740

Pulled By: mrambacher

fbshipit-source-id: fd0f70d15f66611c8498257a9973f7e98ca13839
2021-07-06 09:18:08 -07:00
anand76 a0cbb69421 Fix assertion failure when releasing a handle after secondary cache lookup fails (#8470)
Summary:
When the secondary cache lookup fails, we may still allocate a handle and charge the cache for metadata usage. If the cache is full, this can cause the usage to go over capacity. Later, when a (unrelated) handle is released, it trips up an assertion that checks that usage is less than capacity. To prevent this assertion failure, don't charge the cache for a failed secondary cache lookup.

Tests:
Run crash_test

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8470

Reviewed By: zhichao-cao

Differential Revision: D29474713

Pulled By: anand1976

fbshipit-source-id: 27191969c95470a7b070d292b458efce71395bf2
2021-06-30 13:29:30 -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
Peter Dillinger 416dc7bed7 Clarify some DB::Open,OpenForReadOnly semantics (#8379)
Summary:
Longstanding tech debt

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8379

Test Plan: Better than not having an API contract

Reviewed By: jay-zhuang

Differential Revision: D29011131

Pulled By: pdillinger

fbshipit-source-id: 2c4796177733651954024fc17875f8642ca08d09
2021-06-14 16:09:21 -07:00
Peter Dillinger d5a46c40e5 Pin CacheEntryStatsCollector to fix performance bug (#8385)
Summary:
If the block Cache is full with strict_capacity_limit=false,
then our CacheEntryStatsCollector could be immediately evicted on
release, so iterating through column families with shared block cache
could trigger re-scan for each CF. This change fixes that problem by
pinning the CacheEntryStatsCollector from InternalStats so that it's not
evicted.

I had originally thought that this object could participate in LRU like
everything else, but even though a re-load+re-scan only touches memory,
it can be orders of magnitude more expensive than other cache misses.
One service in Facebook has scans that take ~20s over 100GB block cache
that is mostly 4KB entries. (The up-side of this bug and https://github.com/facebook/rocksdb/issues/8369 is that
we had a natural experiment on the effect on some service metrics even
with block cache scans running continuously in the background--a kind
of worst case scenario. Metrics like latency were not affected enough
to trigger warnings.)

Other smaller fixes:

20s is already a sizable portion of 600s stats dump period, or 180s
default max age to force re-scan, so added logic to ensure that (for
each block cache) we don't spend more than 0.2% of our background thread
time scanning it. Nevertheless, "foreground" requests for cache entry
stats (calls to `db->GetMapProperty(DB::Properties::kBlockCacheEntryStats)`)
are permitted to consume more CPU.

Renamed field to cache_entry_stats_ to match code style.

This change is intended for patching in 6.21 release.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8385

Test Plan:
unit test expanded to cover new logic (detect regression),
some manual testing with db_bench

Reviewed By: ajkr

Differential Revision: D29042759

Pulled By: pdillinger

fbshipit-source-id: 236faa902397f50038c618f50fbc8cf3f277308c
2021-06-14 08:15:11 -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
Peter Dillinger 2f93a3b809 Fix a major performance bug in 6.21 for cache entry stats (#8369)
Summary:
In final polishing of https://github.com/facebook/rocksdb/issues/8297 (after most manual testing), I
broke my own caching layer by sanitizing an input parameter with
std::min(0, x) instead of std::max(0, x). I resisted unit testing the
timing part of the result caching because historically, these test
are either flaky or difficult to write, and this was not a correctness
issue. This bug is essentially unnoticeable with a small number
of column families but can explode background work with a
large number of column families.

This change fixes the logical error, removes some unnecessary related
optimization, and adds mock time/sleeps to the unit test to ensure we
can cache hit within the age limit.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8369

Test Plan: added time testing logic to existing unit test

Reviewed By: ajkr

Differential Revision: D28950892

Pulled By: pdillinger

fbshipit-source-id: e79cd4ff3eec68fd0119d994f1ed468c38026c3b
2021-06-08 05:03:32 -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 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
anand76 13232e11d4 Allow cache_bench/db_bench to use a custom secondary cache (#8312)
Summary:
This PR adds a ```-secondary_cache_uri``` option to the cache_bench and db_bench tools to allow the user to specify a custom secondary cache URI. The object registry is used to create an instance of the ```SecondaryCache``` object of the type specified in the URI.

The main cache_bench code is packaged into a separate library, similar to db_bench.

An example invocation of db_bench with a secondary cache URI -
```db_bench --env_uri=ws://ws.flash_sandbox.vll1_2/ -db=anand/nvm_cache_2 -use_existing_db=true -benchmarks=readrandom -num=30000000 -key_size=32 -value_size=256 -use_direct_reads=true -cache_size=67108864 -cache_index_and_filter_blocks=true  -secondary_cache_uri='cachelibwrapper://filename=/home/anand76/nvm_cache/cache_file;size=2147483648;regionSize=16777216;admPolicy=random;admProbability=1.0;volatileSize=8388608;bktPower=20;lockPower=12' -partition_index_and_filters=true -duration=1800```

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8312

Reviewed By: zhichao-cao

Differential Revision: D28544325

Pulled By: anand1976

fbshipit-source-id: 8f209b9af900c459dc42daa7a610d5f00176eeed
2021-05-19 15:26:18 -07:00
anand76 feb06e83b2 Initial support for secondary cache in LRUCache (#8271)
Summary:
Defined the abstract interface for a secondary cache in include/rocksdb/secondary_cache.h, and updated LRUCacheOptions to take a std::shared_ptr<SecondaryCache>. An item is initially inserted into the LRU (primary) cache. When it ages out and evicted from memory, its inserted into the secondary cache. On a LRU cache miss and successful lookup in the secondary cache, the item is promoted to the LRU cache. Only support synchronous lookup currently. The secondary cache would be used to implement a persistent (flash cache) or compressed cache.

Tests:
Results from cache_bench and db_bench don't show any regression due to these changes.

cache_bench results before and after this change -
Command
```./cache_bench -ops_per_thread=10000000 -threads=1```
Before
```Complete in 40.688 s; QPS = 245774```
```Complete in 40.486 s; QPS = 246996```
```Complete in 42.019 s; QPS = 237989```
After
```Complete in 40.672 s; QPS = 245869```
```Complete in 44.622 s; QPS = 224107```
```Complete in 42.445 s; QPS = 235599```

db_bench results before this change, and with this change + https://github.com/facebook/rocksdb/issues/8213 and https://github.com/facebook/rocksdb/issues/8191 -
Commands
```./db_bench  --benchmarks="fillseq,compact" -num=30000000 -key_size=32 -value_size=256 -use_direct_io_for_flush_and_compaction=true -db=/home/anand76/nvm_cache/db -partition_index_and_filters=true```

```./db_bench -db=/home/anand76/nvm_cache/db -use_existing_db=true -benchmarks=readrandom -num=30000000 -key_size=32 -value_size=256 -use_direct_reads=true -cache_size=1073741824 -cache_numshardbits=6 -cache_index_and_filter_blocks=true -read_random_exp_range=17 -statistics -partition_index_and_filters=true -threads=16 -duration=300```
Before
```
DB path: [/home/anand76/nvm_cache/db]
readrandom   :      80.702 micros/op 198104 ops/sec;   54.4 MB/s (3708999 of 3708999 found)
```
```
DB path: [/home/anand76/nvm_cache/db]
readrandom   :      87.124 micros/op 183625 ops/sec;   50.4 MB/s (3439999 of 3439999 found)
```
After
```
DB path: [/home/anand76/nvm_cache/db]
readrandom   :      77.653 micros/op 206025 ops/sec;   56.6 MB/s (3866999 of 3866999 found)
```
```
DB path: [/home/anand76/nvm_cache/db]
readrandom   :      84.962 micros/op 188299 ops/sec;   51.7 MB/s (3535999 of 3535999 found)
```

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8271

Reviewed By: zhichao-cao

Differential Revision: D28357511

Pulled By: anand1976

fbshipit-source-id: d1cfa236f00e649a18c53328be10a8062a4b6da2
2021-05-13 22:58:40 -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
Jay Zhuang a6e425dc44 Fix a minor clang release build failure (#8290)
Summary:
Error message:
```
cache/clock_cache.cc:434:14: error: implicit conversion loses integer precision: 'size_t' (aka 'unsigned long') to 'uint32_t' (aka 'unsigned int') [-Werror,-Wshorten-64-to-32]
    *state = end_idx;
           ~ ^~~~~~~
```
Make circleci to cover this case by install tbb.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8290

Test Plan: `USE_CLANG=1 make -j1 release`

Reviewed By: akankshamahajan15

Differential Revision: D28374672

Pulled By: jay-zhuang

fbshipit-source-id: e8c3ee46f2a008e8a599413292e5a4b5151365df
2021-05-12 10:45:29 -07:00
Peter Dillinger 78a309bf86 New Cache API for gathering statistics (#8225)
Summary:
Adds a new Cache::ApplyToAllEntries API that we expect to use
(in follow-up PRs) for efficiently gathering block cache statistics.
Notable features vs. old ApplyToAllCacheEntries:

* Includes key and deleter (in addition to value and charge). We could
have passed in a Handle but then more virtual function calls would be
needed to get the "fields" of each entry. We expect to use the 'deleter'
to identify the origin of entries, perhaps even more.
* Heavily tuned to minimize latency impact on operating cache. It
does this by iterating over small sections of each cache shard while
cycling through the shards.
* Supports tuning roughly how many entries to operate on for each
lock acquire and release, to control the impact on the latency of other
operations without excessive lock acquire & release. The right balance
can depend on the cost of the callback. Good default seems to be
around 256.
* There should be no need to disable thread safety. (I would expect
uncontended locks to be sufficiently fast.)

I have enhanced cache_bench to validate this approach:

* Reports a histogram of ns per operation, so we can look at the
ditribution of times, not just throughput (average).
* Can add a thread for simulated "gather stats" which calls
ApplyToAllEntries at a specified interval. We also generate a histogram
of time to run ApplyToAllEntries.

To make the iteration over some entries of each shard work as cleanly as
possible, even with resize between next set of entries, I have
re-arranged which hash bits are used for sharding and which for indexing
within a shard.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8225

Test Plan:
A couple of unit tests are added, but primary validation is manual, as
the primary risk is to performance.

The primary validation is using cache_bench to ensure that neither
the minor hashing changes nor the simulated stats gathering
significantly impact QPS or latency distribution. Note that adding op
latency histogram seriously impacts the benchmark QPS, so for a
fair baseline, we need the cache_bench changes (except remove simulated
stat gathering to make it compile). In short, we don't see any
reproducible difference in ops/sec or op latency unless we are gathering
stats nearly continuously. Test uses 10GB block cache with
8KB values to be somewhat realistic in the number of items to iterate
over.

Baseline typical output:

```
Complete in 92.017 s; Rough parallel ops/sec = 869401
Thread ops/sec = 54662

Operation latency (ns):
Count: 80000000 Average: 11223.9494  StdDev: 29.61
Min: 0  Median: 7759.3973  Max: 9620500
Percentiles: P50: 7759.40 P75: 14190.73 P99: 46922.75 P99.9: 77509.84 P99.99: 217030.58
------------------------------------------------------
[       0,       1 ]       68   0.000%   0.000%
(    2900,    4400 ]       89   0.000%   0.000%
(    4400,    6600 ] 33630240  42.038%  42.038% ########
(    6600,    9900 ] 18129842  22.662%  64.700% #####
(    9900,   14000 ]  7877533   9.847%  74.547% ##
(   14000,   22000 ] 15193238  18.992%  93.539% ####
(   22000,   33000 ]  3037061   3.796%  97.335% #
(   33000,   50000 ]  1626316   2.033%  99.368%
(   50000,   75000 ]   421532   0.527%  99.895%
(   75000,  110000 ]    56910   0.071%  99.966%
(  110000,  170000 ]    16134   0.020%  99.986%
(  170000,  250000 ]     5166   0.006%  99.993%
(  250000,  380000 ]     3017   0.004%  99.996%
(  380000,  570000 ]     1337   0.002%  99.998%
(  570000,  860000 ]      805   0.001%  99.999%
(  860000, 1200000 ]      319   0.000% 100.000%
( 1200000, 1900000 ]      231   0.000% 100.000%
( 1900000, 2900000 ]      100   0.000% 100.000%
( 2900000, 4300000 ]       39   0.000% 100.000%
( 4300000, 6500000 ]       16   0.000% 100.000%
( 6500000, 9800000 ]        7   0.000% 100.000%
```

New, gather_stats=false. Median thread ops/sec of 5 runs:

```
Complete in 92.030 s; Rough parallel ops/sec = 869285
Thread ops/sec = 54458

Operation latency (ns):
Count: 80000000 Average: 11298.1027  StdDev: 42.18
Min: 0  Median: 7722.0822  Max: 6398720
Percentiles: P50: 7722.08 P75: 14294.68 P99: 47522.95 P99.9: 85292.16 P99.99: 228077.78
------------------------------------------------------
[       0,       1 ]      109   0.000%   0.000%
(    2900,    4400 ]      793   0.001%   0.001%
(    4400,    6600 ] 34054563  42.568%  42.569% #########
(    6600,    9900 ] 17482646  21.853%  64.423% ####
(    9900,   14000 ]  7908180   9.885%  74.308% ##
(   14000,   22000 ] 15032072  18.790%  93.098% ####
(   22000,   33000 ]  3237834   4.047%  97.145% #
(   33000,   50000 ]  1736882   2.171%  99.316%
(   50000,   75000 ]   446851   0.559%  99.875%
(   75000,  110000 ]    68251   0.085%  99.960%
(  110000,  170000 ]    18592   0.023%  99.983%
(  170000,  250000 ]     7200   0.009%  99.992%
(  250000,  380000 ]     3334   0.004%  99.997%
(  380000,  570000 ]     1393   0.002%  99.998%
(  570000,  860000 ]      700   0.001%  99.999%
(  860000, 1200000 ]      293   0.000% 100.000%
( 1200000, 1900000 ]      196   0.000% 100.000%
( 1900000, 2900000 ]       69   0.000% 100.000%
( 2900000, 4300000 ]       32   0.000% 100.000%
( 4300000, 6500000 ]       10   0.000% 100.000%
```

New, gather_stats=true, 1 second delay between scans. Scans take about
1 second here so it's spending about 50% time scanning. Still the effect on
ops/sec and latency seems to be in the noise. Median thread ops/sec of 5 runs:

```
Complete in 91.890 s; Rough parallel ops/sec = 870608
Thread ops/sec = 54551

Operation latency (ns):
Count: 80000000 Average: 11311.2629  StdDev: 45.28
Min: 0  Median: 7686.5458  Max: 10018340
Percentiles: P50: 7686.55 P75: 14481.95 P99: 47232.60 P99.9: 79230.18 P99.99: 232998.86
------------------------------------------------------
[       0,       1 ]       71   0.000%   0.000%
(    2900,    4400 ]      291   0.000%   0.000%
(    4400,    6600 ] 34492060  43.115%  43.116% #########
(    6600,    9900 ] 16727328  20.909%  64.025% ####
(    9900,   14000 ]  7845828   9.807%  73.832% ##
(   14000,   22000 ] 15510654  19.388%  93.220% ####
(   22000,   33000 ]  3216533   4.021%  97.241% #
(   33000,   50000 ]  1680859   2.101%  99.342%
(   50000,   75000 ]   439059   0.549%  99.891%
(   75000,  110000 ]    60540   0.076%  99.967%
(  110000,  170000 ]    14649   0.018%  99.985%
(  170000,  250000 ]     5242   0.007%  99.991%
(  250000,  380000 ]     3260   0.004%  99.995%
(  380000,  570000 ]     1599   0.002%  99.997%
(  570000,  860000 ]     1043   0.001%  99.999%
(  860000, 1200000 ]      471   0.001%  99.999%
( 1200000, 1900000 ]      275   0.000% 100.000%
( 1900000, 2900000 ]      143   0.000% 100.000%
( 2900000, 4300000 ]       60   0.000% 100.000%
( 4300000, 6500000 ]       27   0.000% 100.000%
( 6500000, 9800000 ]        7   0.000% 100.000%
( 9800000, 14000000 ]        1   0.000% 100.000%

Gather stats latency (us):
Count: 46 Average: 980387.5870  StdDev: 60911.18
Min: 879155  Median: 1033777.7778  Max: 1261431
Percentiles: P50: 1033777.78 P75: 1120666.67 P99: 1261431.00 P99.9: 1261431.00 P99.99: 1261431.00
------------------------------------------------------
(  860000, 1200000 ]       45  97.826%  97.826% ####################
( 1200000, 1900000 ]        1   2.174% 100.000%

Most recent cache entry stats:
Number of entries: 1295133
Total charge: 9.88 GB
Average key size: 23.4982
Average charge: 8.00 KB
Unique deleters: 3
```

Reviewed By: mrambacher

Differential Revision: D28295742

Pulled By: pdillinger

fbshipit-source-id: bbc4a552f91ba0fe10e5cc025c42cef5a81f2b95
2021-05-11 16:17:10 -07:00
Peter Dillinger 3b981eaa1d Fix use-after-free threading bug in ClockCache (#8261)
Summary:
In testing for https://github.com/facebook/rocksdb/issues/8225 I found cache_bench would crash with
-use_clock_cache, as well as db_bench -use_clock_cache, but not
single-threaded. Smaller cache size hits failure much faster. ASAN
reported the failuer as calling malloc_usable_size on the `key` pointer
of a ClockCache handle after it was reportedly freed. On detailed
inspection I found this bad sequence of operations for a cache entry:

state=InCache=1,refs=1
[thread 1] Start ClockCacheShard::Unref (from Release, no mutex)
[thread 1] Decrement ref count
state=InCache=1,refs=0
[thread 1] Suspend before CalcTotalCharge (no mutex)

[thread 2] Start UnsetInCache (from Insert, mutex held)
[thread 2] clear InCache bit
state=InCache=0,refs=0
[thread 2] Calls RecycleHandle (based on pre-updated state)
[thread 2] Returns to Insert which calls Cleanup which deletes `key`

[thread 1] Resume ClockCacheShard::Unref
[thread 1] Read `key` in CalcTotalCharge

To fix this, I've added a field to the handle to store the metadata
charge so that we can efficiently remember everything we need from
the handle in Unref. We must not read from the handle again if we
decrement the count to zero with InCache=1, which means we don't own
the entry and someone else could eject/overwrite it immediately.

Note before this change, on amd64 sizeof(Handle) == 56 even though there
are only 48 bytes of data. Grouping together the uint32_t fields would
cut it down to 48, but I've added another uint32_t, which takes it
back up to 56. Not a big deal.

Also fixed DisownData to cooperate with ASAN as in LRUCache.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8261

Test Plan:
Manual + adding use_clock_cache to db_crashtest.py

Base performance
./cache_bench -use_clock_cache
Complete in 17.060 s; QPS = 2458513
New performance
./cache_bench -use_clock_cache
Complete in 17.052 s; QPS = 2459695

Any difference is easily buried in small noise.

Crash test shows still more bug(s) in ClockCache, so I'm expecting to
disable ClockCache from production code in a follow-up PR (if we
can't find and fix the bug(s))

Reviewed By: mrambacher

Differential Revision: D28207358

Pulled By: pdillinger

fbshipit-source-id: aa7a9322afc6f18f30e462c75dbbe4a1206eb294
2021-05-04 22:18:00 -07:00
storagezhang 711881bc25 Fix some typos in comments (#8066)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8066

Reviewed By: jay-zhuang

Differential Revision: D27280799

Pulled By: mrambacher

fbshipit-source-id: 68f91f5af4ffe0a84be581961bf9366887f47702
2021-03-25 21:18:08 -07:00
storagezhang d9be6556aa Include C++ standard library headers instead of C compatibility headers (#8068)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8068

Reviewed By: zhichao-cao

Differential Revision: D27147685

Pulled By: riversand963

fbshipit-source-id: 5428b1c0142ecae17c977fba31a6d49b52983d1c
2021-03-19 12:09:47 -07:00
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
Dylan Wen a65e905bbb Fix typos in comments (#7687)
Summary:
Hi there,

This PR fixes a few typos in comments in `cache/lru_cache.h`.

Thanks

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7687

Reviewed By: ajkr

Differential Revision: D25064674

Pulled By: jay-zhuang

fbshipit-source-id: fe633369d5b82c5aac42d4ee8d551b9d657237d1
2020-11-19 13:32:50 -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
Levi Tamasi e8cb32ed67 Introduce BlobFileCache and add support for blob files to Get() (#7540)
Summary:
The patch adds blob file support to the `Get` API by extending `Version` so that
whenever a blob reference is read from a file, the blob is retrieved from the corresponding
blob file and passed back to the caller. (This is assuming the blob reference is valid
and the blob file is actually part of the given `Version`.) It also introduces a cache
of `BlobFileReader`s called `BlobFileCache` that enables sharing `BlobFileReader`s
between callers. `BlobFileCache` uses the same backing cache as `TableCache`, so
`max_open_files` (if specified) limits the total number of open (table + blob) files.

TODO: proactively open/cache blob files and pin the cache handles of the readers in the
metadata objects similarly to what `VersionBuilder::LoadTableHandlers` does for
table files.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7540

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D24260219

Pulled By: ltamasi

fbshipit-source-id: a8a2a4f11d3d04d6082201b52184bc4d7b0857ba
2020-10-15 13:04:47 -07:00
Peter Dillinger 08552b19d3 Genericize and clean up FastRange (#7436)
Summary:
A generic algorithm in progress depends on a templatized
version of fastrange, so this change generalizes it and renames
it to fit our style guidelines, FastRange32, FastRange64, and now
FastRangeGeneric.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7436

Test Plan: added a few more test cases

Reviewed By: jay-zhuang

Differential Revision: D23958153

Pulled By: pdillinger

fbshipit-source-id: 8c3b76101653417804997e5f076623a25586f3e8
2020-09-28 11:35:00 -07:00
mrambacher 7d472accdc Bring the Configurable options together (#5753)
Summary:
This PR merges the functionality of making the ColumnFamilyOptions, TableFactory, and DBOptions into Configurable into a single PR, resolving any merge conflicts

Pull Request resolved: https://github.com/facebook/rocksdb/pull/5753

Reviewed By: ajkr

Differential Revision: D23385030

Pulled By: zhichao-cao

fbshipit-source-id: 8b977a7731556230b9b8c5a081b98e49ee4f160a
2020-09-14 17:01:01 -07:00
mrambacher 56f468b356 Add more tests to ASSERT_STATUS_CHECKED (#7211)
Summary:
Added 4 more tests to those which pass ASSERT_STATUS_CHECKED (cache_test, lru_cache_test, filename_test, filelock_test).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7211

Reviewed By: ajkr

Differential Revision: D22982858

Pulled By: zhichao-cao

fbshipit-source-id: acdd071582ed6aa7447ed96c5732f10bf720d783
2020-08-06 17:19:41 -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
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
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
yetingsky 3f218074ee fix typo (#6831)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/6831

Reviewed By: cheng-chang

Differential Revision: D21499149

Pulled By: zhichao-cao

fbshipit-source-id: 2cb76cbf7086677d8cad5c828019e008062f0052
2020-05-11 14:58:25 -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 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
Peter Dillinger 079e77ff9e Revamp cache_bench to resemble a real workload (#6629)
Summary:
I suspect LRUCache could use some optimization, and to support
such an effort, a good benchmarking tool is needed. The existing
cache_bench was heavily skewed toward insertion and lookup misses, and
did not saturate memory with other work. This change should improve
those things to better resemble a real workload.

(All below using clang compiler, for some consistency, but not
necessarily same version and settings.)

The real workload is from production MySQL on RocksDB, filtering stacks
containing "LRU", "ShardedCache" or "CacheShard."
Lookup inclusive: 66%
Insert inclusive: 17%
Release inclusive: 15%

An alternate simulated workload is MySQL running a LinkBench read test:
Lookup inclusive: 54%
Insert inclusive: 24%
Release inclusive: 21%

cache_bench default settings, prior to this change:
Lookup inclusive: 35.8%
Insert inclusive: 63.6%
Release inclusive: 0%

cache_bench after this change (intended as somewhat "tighter" workload
than average production, more like LinkBench):
Lookup inclusive: 52%
Insert inclusive: 20%
Release inclusive: 26%

And top exclusive stacks (portion of stack samples as filtered above):
Production MySQL:
LRUHandleTable::FindPointer: 25.3%
rocksdb::operator==: 15.1%  <-- Slice ==
LRUCacheShard::LRU_Remove: 13.8%
ShardedCache::Lookup: 8.9%
__pthread_mutex_lock: 7.1%
LRUCacheShard::LRU_Insert: 6.3%
MurmurHash64A: 4.8%  <-- Since upgraded to XXH3p
...

Old cache_bench:
LRUHandleTable::FindPointer: 23.6%
__pthread_mutex_lock: 15.0%
__pthread_mutex_unlock_usercnt: 11.7%
__lll_lock_wait: 8.6%
__lll_unlock_wake: 6.8%
LRUCacheShard::LRU_Insert: 6.0%
ShardedCache::Lookup: 4.4%
LRUCacheShard::LRU_Remove: 2.8%
...
rocksdb::operator==: 0.2%  <-- Slice ==
...

New cache_bench:
LRUHandleTable::FindPointer: 22.8%
__pthread_mutex_unlock_usercnt: 14.3%
rocksdb::operator==: 10.5%  <-- Slice ==
LRUCacheShard::LRU_Insert: 9.0%
__pthread_mutex_lock: 5.9%
LRUCacheShard::LRU_Remove: 5.0%
...
ShardedCache::Lookup: 2.9%
...

So there's a bit more lock contention in the benchmark than in
production, but otherwise looks similar enough to me. At least it's a
big improvement over the existing code.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6629

Test Plan: No production code changes, ran cache_bench with ASAN

Reviewed By: ltamasi

Differential Revision: D20824318

Pulled By: pdillinger

fbshipit-source-id: 6f8dc5891ead0f87edbed3a615ecd5289d9abe12
2020-04-03 10:26:49 -07:00
Levi Tamasi e6f86cfb36 Revert the recent cache deleter change (#6620)
Summary:
Revert "Use function objects as deleters in the block cache (https://github.com/facebook/rocksdb/issues/6545)"

    This reverts commit 6301dbe7a7.

    Revert "Call out the cache deleter related interface change in HISTORY.md (https://github.com/facebook/rocksdb/issues/6606)"

    This reverts commit 3a35542f86.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6620

Test Plan: `make check`

Reviewed By: zhichao-cao

Differential Revision: D20773311

Pulled By: ltamasi

fbshipit-source-id: 7637a761f718f323ef0e7da959462e8fb06e7a2b
2020-03-31 16:11:06 -07:00
Levi Tamasi 6301dbe7a7 Use function objects as deleters in the block cache (#6545)
Summary:
As the first step of reintroducing eviction statistics for the block
cache, the patch switches from using simple function pointers as deleters
to function objects implementing an interface. This will enable using
deleters that have state, like a smart pointer to the statistics object
that is to be updated when an entry is removed from the cache. For now,
the patch adds a deleter template class `SimpleDeleter`, which simply
casts the `value` pointer to its original type and calls `delete` or
`delete[]` on it as appropriate. Note: to prevent object lifecycle
issues, deleters must outlive the cache entries referring to them;
`SimpleDeleter` ensures this by using the ("leaky") Meyers singleton
pattern.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6545

Test Plan: `make asan_check`

Reviewed By: siying

Differential Revision: D20475823

Pulled By: ltamasi

fbshipit-source-id: fe354c33dd96d9bafc094605462352305449a22a
2020-03-26 16:19:58 -07:00
sdong fdf882ded2 Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433)
Summary:
When dynamically linking two binaries together, different builds of RocksDB from two sources might cause errors. To provide a tool for user to solve the problem, the RocksDB namespace is changed to a flag which can be overridden in build time.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6433

Test Plan: Build release, all and jtest. Try to build with ROCKSDB_NAMESPACE with another flag.

Differential Revision: D19977691

fbshipit-source-id: aa7f2d0972e1c31d75339ac48478f34f6cfcfb3e
2020-02-20 12:09:57 -08:00
anand76 16fa6fd2a6 Remove key length assertion LRUHandle::CalcTotalCharge (#6115)
Summary:
Inserting an entry in the block cache with 0 length key is a valid use case. Remove the assertion in ```LRUHandle::CalcTotalCharge```.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6115

Differential Revision: D18769693

Pulled By: anand1976

fbshipit-source-id: 34cc159650300dda6d7273480640478f28392cda
2019-12-02 15:00:07 -08:00
Peter Dillinger ca7ccbe2ea Misc hashing updates / upgrades (#5909)
Summary:
- Updated our included xxhash implementation to version 0.7.2 (== the latest dev version as of 2019-10-09).
- Using XXH_NAMESPACE (like other fb projects) to avoid potential name collisions.
- Added fastrange64, and unit tests for it and fastrange32. These are faster alternatives to hash % range.
- Use preview version of XXH3 instead of MurmurHash64A for NPHash64
-- Had to update cache_test to increase probability of passing for any given hash function.
- Use fastrange64 instead of % with uses of NPHash64
-- Had to fix WritePreparedTransactionTest.CommitOfDelayedPrepared to avoid deadlock apparently caused by new hash collision.
- Set default seed for NPHash64 because specifying a seed rarely makes sense for it.
- Removed unnecessary include xxhash.h in a popular .h file
- Rename preview version of XXH3 to XXH3p for clarity and to ease backward compatibility in case final version of XXH3 is integrated.

Relying on existing unit tests for NPHash64-related changes. Each new implementation of fastrange64 passed unit tests when manipulating my local build to select it. I haven't done any integration performance tests, but I consider the improved performance of the pieces being swapped in to be well established.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5909

Differential Revision: D18125196

Pulled By: pdillinger

fbshipit-source-id: f6bf83d49d20cbb2549926adf454fd035f0ecc0d
2019-10-24 17:16:46 -07:00
sdong e8263dbdaa Apply formatter to recent 200+ commits. (#5830)
Summary:
Further apply formatter to more recent commits.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5830

Test Plan: Run all existing tests.

Differential Revision: D17488031

fbshipit-source-id: 137458fd94d56dd271b8b40c522b03036943a2ab
2019-09-20 12:04:26 -07:00
Maysam Yabandeh 9a87ae46fd Use total charge in MaintainPoolSize (#5813)
Summary:
https://github.com/facebook/rocksdb/issues/5797 charges the block cache with the total of user-provided charge plus the metadata charge. It had a bug where in MaintainPoolSize the user-provided charge was used instead of the total charge. The patch fixes that.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5813

Differential Revision: D17412783

Pulled By: maysamyabandeh

fbshipit-source-id: 45c0ac9f1e2233760db5ccd61399605cd74edc87
2019-09-17 00:16:13 -07:00
Maysam Yabandeh 638d239507 Charge block cache for cache internal usage (#5797)
Summary:
For our default block cache, each additional entry has extra memory overhead. It include LRUHandle (72 bytes currently) and the cache key (two varint64, file id and offset). The usage is not negligible. For example for block_size=4k, the overhead accounts for an extra 2% memory usage for the cache. The patch charging the cache for the extra usage, reducing untracked memory usage outside block cache. The feature is enabled by default and can be disabled by passing kDontChargeCacheMetadata to the cache constructor.
This PR builds up on https://github.com/facebook/rocksdb/issues/4258
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5797

Test Plan:
- Existing tests are updated to either disable the feature when the test has too much dependency on the old way of accounting the usage or increasing the cache capacity to account for the additional charge of metadata.
- The Usage tests in cache_test.cc are augmented to test the cache usage under kFullChargeCacheMetadata.

Differential Revision: D17396833

Pulled By: maysamyabandeh

fbshipit-source-id: 7684ccb9f8a40ca595e4f5efcdb03623afea0c6f
2019-09-16 15:26:21 -07:00
Eli Pozniansky 74fb7f0ba5 Cleaned up and simplified LRU cache implementation (#5579)
Summary:
The 'refs' field in LRUHandle now counts only external references, since anyway we already have the IN_CACHE flag. This simplifies reference accounting logic a bit. Also cleaned up few asserts code as well as the comments - to be more readable.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5579

Differential Revision: D16286747

Pulled By: elipoz

fbshipit-source-id: 7186d88f80f512ce584d0a303437494b5cbefd7f
2019-07-16 19:17:45 -07:00
sdong 15fd3be07b LRU Cache to enable mid-point insertion by default (#5508)
Summary:
Mid-point insertion is a useful feature and is mature now. Make it default. Also changed cache_index_and_filter_blocks_with_high_priority=true as default accordingly, so that we won't evict index and filter blocks easier after the change, to avoid too many surprises to users.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5508

Test Plan: Run all existing tests.

Differential Revision: D16021179

fbshipit-source-id: ce8456e8d43b3bfb48df6c304b5290a9d19817eb
2019-06-27 10:20:57 -07:00
Vaibhav Gogte f46a2a0375 Export Cache::GetCharge (#5476)
Summary:
Exporting GetCharge to cache.hh
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5476

Differential Revision: D15881882

Pulled By: riversand963

fbshipit-source-id: 3d99084d10059b4fcaaaba240606ed50bc23351c
2019-06-18 17:35:41 -07:00
Zhongyi Xie d68f9f4580 simplify include directive involving inttypes (#5402)
Summary:
When using `PRIu64` type of printf specifier, current code base does the following:
```
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
```
However, this can be simplified to
```
#include <cinttypes>
```
as long as flag `-std=c++11` is used.
This should solve issues like https://github.com/facebook/rocksdb/issues/5159
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5402

Differential Revision: D15701195

Pulled By: miasantreble

fbshipit-source-id: 6dac0a05f52aadb55e9728038599d3d2e4b59d03
2019-06-06 13:56:07 -07:00
Siying Dong 8843129ece Move some memory related files from util/ to memory/ (#5382)
Summary:
Move arena, allocator, and memory tools under util to a separate memory/ directory.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5382

Differential Revision: D15564655

Pulled By: siying

fbshipit-source-id: 9cd6b5d0d3d52b39606e19221fa154596e5852a5
2019-05-30 17:44:09 -07:00
Siying Dong e9e0101ca4 Move test related files under util/ to test_util/ (#5377)
Summary:
There are too many types of files under util/. Some test related files don't belong to there or just are just loosely related. Mo
ve them to a new directory test_util/, so that util/ is cleaner.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5377

Differential Revision: D15551366

Pulled By: siying

fbshipit-source-id: 0f5c8653832354ef8caa31749c0143815d719e2c
2019-05-30 11:25:51 -07:00
Siying Dong 0bb555630f Consolidate hash function used for non-persistent data in a new function (#5155)
Summary:
Create new function NPHash64() and GetSliceNPHash64(), which are currently
implemented using murmurhash.
Replace the current direct call of murmurhash() to use the new functions
if the hash results are not used in on-disk format.
This will make it easier to try out or switch to alternative functions
in the uses where data format compatibility doesn't need to be considered.
This part shouldn't have any performance impact.

Also, the sharded cache hash function is changed to the new format, because
it falls into this categoery. It doesn't show visible performance impact
in db_bench results. CPU showed by perf is increased from about 0.2% to 0.4%
in an extreme benchmark setting (4KB blocks, no-compression, everything
cached in block cache). We've known that the current hash function used,
our own Hash() has serious hash quality problem. It can generate a lots of
conflicts with similar input. In this use case, it means extra lock contention
for reads from the same file. This slight CPU regression is worthy to me
to counter the potential bad performance with hot keys. And hopefully this
will get further improved in the future with a better hash function.

cache_test's condition is relaxed a little bit to. The new hash is slightly
more skewed in this use case, but I manually checked the data and see
the hash results are still in a reasonable range.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5155

Differential Revision: D14834821

Pulled By: siying

fbshipit-source-id: ec9a2c0a2f8ae4b54d08b13a5c2e9cc97aa80cb5
2019-04-08 13:32:06 -07:00
Siying Dong 479c566771 Add final annotations to some cache functions (#5156)
Summary:
cache functions heavily use virtual functions.
Add some "final" annotations to give compilers more information
to optimize. The compiler doesn't seem to take advantage of it
though. But it doesn't hurt.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5156

Differential Revision: D14814837

Pulled By: siying

fbshipit-source-id: 4423f58eafc93f7dd3c5f04b02b5c993dba2ea94
2019-04-05 16:08:01 -07:00
Siying Dong 2b4d5ceb47 Remove some "using std::..." from header files. (#5113)
Summary:
The code convention we are following, Google C++ Style, discourage
alias in header files, especially public headers:
https://google.github.io/styleguide/cppguide.html#Aliases
Remove some of them. Might removed some from .cc files as well to be consistent.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5113

Differential Revision: D14633030

Pulled By: siying

fbshipit-source-id: b990edc919d5de60295992284f980195e501d424
2019-03-27 10:28:21 -07:00
Levi Tamasi 34f8ac0c99 Make adaptivity of LRU cache mutexes configurable (#5054)
Summary:
The patch adds a new config option to LRUCacheOptions that enables
users to choose whether to use an adaptive mutex for the LRU block
cache (on platforms where adaptive mutexes are supported). The default
is true if RocksDB is compiled with -DROCKSDB_DEFAULT_TO_ADAPTIVE_MUTEX,
false otherwise.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5054

Differential Revision: D14542749

Pulled By: ltamasi

fbshipit-source-id: 0065715ab6cf91f10444b737fed8c8aee6a8a0d2
2019-03-20 12:33:44 -07:00
Levi Tamasi f83eecff99 Introduce an enum for flag types in LRUHandle (#5024)
Summary:
Replace the integers used for setting and querying the various
flags in LRUHandle with enum values to improve readability.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5024

Differential Revision: D14263429

Pulled By: ltamasi

fbshipit-source-id: b1b9ba95635265f122c2b40da73850eaac18227a
2019-02-28 11:54:24 -08:00
Michael Liu ca89ac2ba9 Apply modernize-use-override (2nd iteration)
Summary:
Use C++11’s override and remove virtual where applicable.
Change are automatically generated.

Reviewed By: Orvid

Differential Revision: D14090024

fbshipit-source-id: 1e9432e87d2657e1ff0028e15370a85d1739ba2a
2019-02-14 14:41:36 -08:00
Yi Wu 05d9d82181 Revert "Move MemoryAllocator option from Cache to BlockBasedTableOpti… (#4697)
Summary:
…ons (#4676)"

This reverts commit b32d087dbb.

`MemoryAllocator` needs to be with `Cache`, since cache entry can
outlive DB and block based table. The cache needs to hold reference to
memory allocator when deleting cache entry.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4697

Differential Revision: D13133490

Pulled By: yiwu-arbug

fbshipit-source-id: 8ef7e8a51263bfd929f892fd062665ff4ce9ce5a
2018-11-21 11:29:57 -08:00
Yi Wu b32d087dbb Move MemoryAllocator option from Cache to BlockBasedTableOptions (#4676)
Summary:
Per offline discussion with siying, `MemoryAllocator` and `Cache` should be decouple. The idea is that memory allocator handles memory allocation, while cache handle cache policy.

It is normal that external cache libraries pack couple the two components for better optimization. If we want to integrate with such library in the future, we can make a wrapper of the library implementing both `Cache` and `MemoryAllocator` interface.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4676

Differential Revision: D13047662

Pulled By: yiwu-arbug

fbshipit-source-id: cd42e246d80ab600b4de47d073f7d2db308ce6dd
2018-11-13 13:48:38 -08:00
Sagar Vemuri dc3528077a Update all unique/shared_ptr instances to be qualified with namespace std (#4638)
Summary:
Ran the following commands to recursively change all the files under RocksDB:
```
find . -type f -name "*.cc" -exec sed -i 's/ unique_ptr/ std::unique_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/<unique_ptr/<std::unique_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/ shared_ptr/ std::shared_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/<shared_ptr/<std::shared_ptr/g' {} +
```
Running `make format` updated some formatting on the files touched.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4638

Differential Revision: D12934992

Pulled By: sagar0

fbshipit-source-id: 45a15d23c230cdd64c08f9c0243e5183934338a8
2018-11-09 11:19:58 -08:00
Yi Wu f560c8f5c8 s/CacheAllocator/MemoryAllocator/g (#4590)
Summary:
Rename the interface, as it is mean to be a generic interface for memory allocation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4590

Differential Revision: D10866340

Pulled By: yiwu-arbug

fbshipit-source-id: 85cb753351a40cb856c046aeaa3f3b369eef3d16
2018-10-26 14:30:30 -07:00
Igor Canadi 1cf5deb8fd Introduce CacheAllocator, a custom allocator for cache blocks (#4437)
Summary:
This is a conceptually simple change, but it touches many files to
pass the allocator through function calls.

We introduce CacheAllocator, which can be used by clients to configure
custom allocator for cache blocks. Our motivation is to hook this up
with folly's `JemallocNodumpAllocator`
(f43ce6d686/folly/experimental/JemallocNodumpAllocator.h),
but there are many other possible use cases.

Additionally, this commit cleans up memory allocation in
`util/compression.h`, making sure that all allocations are wrapped in a
unique_ptr as soon as possible.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4437

Differential Revision: D10132814

Pulled By: yiwu-arbug

fbshipit-source-id: be1343a4b69f6048df127939fea9bbc96969f564
2018-10-02 17:24:58 -07:00
Yanqin Jin 26d67e357e Support group commits of version edits (#3944)
Summary:
This PR supports the group commit of multiple version edit entries corresponding to different column families. Column family drop/creation still cannot be grouped. This PR is a subset of [PR 3752](https://github.com/facebook/rocksdb/pull/3752).
Closes https://github.com/facebook/rocksdb/pull/3944

Differential Revision: D8432536

Pulled By: riversand963

fbshipit-source-id: 8f11bd05193b6c0d9272d82e44b676abfac113cb
2018-06-28 12:34:39 -07:00
Taewook Oh b557499eee Suppress leak warning for clang(LLVM) asan (#4066)
Summary:
Instead of __SANITIZE_ADDRESS__ macro, LLVM uses __has_feature(address_sanitzer) to check if ASAN is enabled for the build. I tested it with MySQL sanitizer build that uses RocksDB as a submodule.
Closes https://github.com/facebook/rocksdb/pull/4066

Reviewed By: riversand963

Differential Revision: D8668941

Pulled By: taewookoh

fbshipit-source-id: af4d1da180c1470d257a228f431eebc61490bc36
2018-06-27 22:13:48 -07:00
Yi Wu 724855c7da Fix LRUCache missing null check on destruct
Summary:
Fix LRUCache missing null check on destruct. The check is needed if LRUCache::DisownData is called.
Closes https://github.com/facebook/rocksdb/pull/3920

Differential Revision: D8191631

Pulled By: yiwu-arbug

fbshipit-source-id: d5014f6e49b51692c18a25fb55ece935f5a023c4
2018-05-29 15:13:09 -07:00
Yi Wu bc7e8d472e LRUCache midpoint insertion
Summary:
Implement midpoint insertion strategy where new blocks will be insert to the middle of LRU list, then move the head on the first hit in cache.
Closes https://github.com/facebook/rocksdb/pull/3877

Differential Revision: D8100895

Pulled By: yiwu-arbug

fbshipit-source-id: f4bd83cb8be469e5d02072cfc8bd66011391f3da
2018-05-24 15:57:33 -07:00
Yi Wu 7a99c04311 refactor constructor of LRUCacheShard
Summary:
Update LRUCacheShard constructor so that adding new params to it don't need to add extra SetXXX() methods.
Closes https://github.com/facebook/rocksdb/pull/3896

Differential Revision: D8128618

Pulled By: yiwu-arbug

fbshipit-source-id: 6afa715de1493a50de413678761a765e3af9b83b
2018-05-23 18:57:42 -07:00
David Lai 3be9b36453 comment unused parameters to turn on -Wunused-parameter flag
Summary:
This PR comments out the rest of the unused arguments which allow us to turn on the -Wunused-parameter flag. This is the second part of a codemod relating to https://github.com/facebook/rocksdb/pull/3557.
Closes https://github.com/facebook/rocksdb/pull/3662

Differential Revision: D7426121

Pulled By: Dayvedde

fbshipit-source-id: 223994923b42bd4953eb016a0129e47560f7e352
2018-04-12 17:59:16 -07:00
Yi Wu 685912d07f Clock cache should check if deleter is nullptr before calling it
Summary:
Clock cache should check if deleter is nullptr before calling it.
Closes https://github.com/facebook/rocksdb/pull/3677

Differential Revision: D7493602

Pulled By: yiwu-arbug

fbshipit-source-id: 4f94b188d2baf2cbc7c0d5da30fea1215a683de4
2018-04-05 11:57:53 -07:00
Andrew Kryczka 5d68243e61 Comment out unused variables
Summary:
Submitting on behalf of another employee.
Closes https://github.com/facebook/rocksdb/pull/3557

Differential Revision: D7146025

Pulled By: ajkr

fbshipit-source-id: 495ca5db5beec3789e671e26f78170957704e77e
2018-03-05 13:13:41 -08:00
Igor Sugak aba3409740 Back out "[codemod] - comment out unused parameters"
Reviewed By: igorsugak

fbshipit-source-id: 4a93675cc1931089ddd574cacdb15d228b1e5f37
2018-02-22 12:43:17 -08:00
David Lai f4a030ce81 - comment out unused parameters
Reviewed By: everiq, igorsugak

Differential Revision: D7046710

fbshipit-source-id: 8e10b1f1e2aecebbfb229c742e214db887e5a461
2018-02-22 09:44:23 -08:00
Agam Brahma c3401846ef Minor typo in comment (s/pro/pri)
Summary: Closes https://github.com/facebook/rocksdb/pull/3460

Differential Revision: D6895365

Pulled By: miasantreble

fbshipit-source-id: 04f633d1971b1f542ac28118b738ceb0242a0228
2018-02-03 18:27:14 -08:00
Andrew Kryczka 63f1c0a57d fix gflags namespace
Summary:
I started adding gflags support for cmake on linux and got frustrated that I'd need to duplicate the build_detect_platform logic, which determines namespace based on attempting compilation. We can do it differently -- use the GFLAGS_NAMESPACE macro if available, and if not, that indicates it's an old gflags version without configurable namespace so we can simply hardcode "google".
Closes https://github.com/facebook/rocksdb/pull/3212

Differential Revision: D6456973

Pulled By: ajkr

fbshipit-source-id: 3e6d5bde3ca00d4496a120a7caf4687399f5d656
2017-12-01 10:42:05 -08:00
Phani Shekhar Mantripragada 4b65cfc723 Support for block_cache num_shards and other config via option string.
Summary:
Problem: Option string accepts only cache_size as parameter for block_cache which is specified as "block_cache=1M".
It doesn't accept other parameters like num_shards etc.

Changes :
1) ParseBlockBasedTableOption in block_based_table_factory is edited to accept cache options in the format "block_cache=<cache_size>:<num_shard_bits>:<strict_capacity_limit>:<high_pri_pool_ratio>".
Options other than cache_size are optional to maintain backward compatibility. The changes are valid for block_cache_compressed as well.
For example, "block_cache=1M:6:true:0.5", "block_cache=1M:6:true", "block_cache=1M:6" and "block_cache=1M" are all valid option strings.

2) Corresponding unit tests are added.
Closes https://github.com/facebook/rocksdb/pull/3108

Differential Revision: D6420997

Pulled By: sagar0

fbshipit-source-id: cdea8b785688d2802907974af27225ccc1c0cd43
2017-11-28 10:48:53 -08:00
Prashant D d9240b548c Fix coverity uninitialized fields warnings in lru_cache
Summary:
Coverity uninitialized member variable warnings in lru_cache
Closes https://github.com/facebook/rocksdb/pull/3082

Differential Revision: D6173062

Pulled By: sagar0

fbshipit-source-id: 7bcfc653457bd362d46045d06527838c9a6adad6
2017-10-27 11:26:43 -07:00
raistlin ee2b1ec1e8 Fix unstable floating point exception
Summary:
Fix unstable floating point exception, tested on Windows, 64-bit build.
The problem appeared in `SetCapacity()` method at line

`high_pri_pool_capacity_ = capacity_ * high_pri_pool_ratio_;`

`high_pri_pool_ratio_` was not initialized at that moment, because
`SetHighPriorityPoolRatio()` is called after `SetCapacity()`. So,
`high_pri_pool_ratio_` contained garbage, which caused "Floating point
exception" sometimes.
Closes https://github.com/facebook/rocksdb/pull/3052

Differential Revision: D6111161

Pulled By: yiwu-arbug

fbshipit-source-id: d170329111ad12b4bf9bbcf37bcb6411523438ae
2017-10-20 10:12:49 -07:00
Dmitri Smirnov 0ec90a7cc2 Add -DPORTABLE=1 to MSVC CI build
Summary:
Add -DPORTABLE=1
  port::cacheline_aligned_alloc() has arguments swapped which prevents every single test from running.
Closes https://github.com/facebook/rocksdb/pull/2815

Differential Revision: D5751661

Pulled By: siying

fbshipit-source-id: e0857d6e138ec46035b3c23d7c3c751901a0a4a0
2017-08-31 16:42:48 -07:00
Yi Wu e83d6a02e3 Not using aligned_alloc with gcc4 + asan
Summary:
GCC < 5 + ASAN does not instrument aligned_alloc, which can make ASAN
report false-positive with "free on address which was not malloc" error.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61693

Also suppress leak warning with LRUCache::DisownData().
Closes https://github.com/facebook/rocksdb/pull/2783

Differential Revision: D5696465

Pulled By: yiwu-arbug

fbshipit-source-id: 87c607c002511fa089b18cc35e24909bee0e74b4
2017-08-29 21:56:02 -07:00
Archit Mishra 09ac6206ab Circumvent ASAN false positive
Summary:
Changes:
* checks if ASAN mode is on, and uses malloc and free in the constructor and destructor
Closes https://github.com/facebook/rocksdb/pull/2767

Differential Revision: D5671243

Pulled By: armishra

fbshipit-source-id: 8e4ad0f7f163400c4effa8617d3b30134119d802
2017-08-21 12:10:43 -07:00
yiwu-arbug e367774d19 Overload new[] to properly align LRUCacheShard
Summary:
Also verify it fixes gcc7 compile failure #2672 (see also #2699)
Closes https://github.com/facebook/rocksdb/pull/2732

Differential Revision: D5620348

Pulled By: yiwu-arbug

fbshipit-source-id: 87db657ab734f23b1bfaaa9db9b9956d10eaef59
2017-08-14 14:41:56 -07:00
Siying Dong 21696ba502 Replace dynamic_cast<>
Summary:
Replace dynamic_cast<> so that users can choose to build with RTTI off, so that they can save several bytes per object, and get tiny more memory available.
Some nontrivial changes:
1. Add Comparator::GetRootComparator() to get around the internal comparator hack
2. Add the two experiemental functions to DB
3. Add TableFactory::GetOptionString() to avoid unnecessary casting to get the option string
4. Since 3 is done, move the parsing option functions for table factory to table factory files too, to be symmetric.
Closes https://github.com/facebook/rocksdb/pull/2645

Differential Revision: D5502723

Pulled By: siying

fbshipit-source-id: fd13cec5601cf68a554d87bfcf056f2ffa5fbf7c
2017-07-28 16:27:16 -07:00
Daniel Black 16e0388205 LRUCacheShard cache line size alignment
Summary:
combining #2568 and #2612.
Closes https://github.com/facebook/rocksdb/pull/2620

Differential Revision: D5464394

Pulled By: IslamAbdelRahman

fbshipit-source-id: 9f71d3058dd6adaf02ce3b2de3a81a1228009778
2017-07-24 10:54:37 -07:00
Sagar Vemuri 72502cf227 Revert "comment out unused parameters"
Summary:
This reverts the previous commit 1d7048c598, which broke the build.

Did a `git revert 1d7048c`.
Closes https://github.com/facebook/rocksdb/pull/2627

Differential Revision: D5476473

Pulled By: sagar0

fbshipit-source-id: 4756ff5c0dfc88c17eceb00e02c36176de728d06
2017-07-21 18:26:26 -07:00
Victor Gao 1d7048c598 comment out unused parameters
Summary: This uses `clang-tidy` to comment out unused parameters (in functions, methods and lambdas) in fbcode. Cases that the tool failed to handle are fixed manually.

Reviewed By: igorsugak

Differential Revision: D5454343

fbshipit-source-id: 5dee339b4334e25e963891b519a5aa81fbf627b2
2017-07-21 14:57:44 -07:00
Sushma Devendrappa 0655b58582 enable PinnableSlice for RowCache
Summary:
This patch enables using PinnableSlice for RowCache, changes include
not releasing the cache handle immediately after lookup in TableCache::Get, instead pass a Cleanble function which does Cache::RleaseHandle.
Closes https://github.com/facebook/rocksdb/pull/2492

Differential Revision: D5316216

Pulled By: maysamyabandeh

fbshipit-source-id: d2a684bd7e4ba73772f762e58a82b5f4fbd5d362
2017-07-17 15:08:30 -07:00
Siying Dong 3c327ac2d0 Change RocksDB License
Summary: Closes https://github.com/facebook/rocksdb/pull/2589

Differential Revision: D5431502

Pulled By: siying

fbshipit-source-id: 8ebf8c87883daa9daa54b2303d11ce01ab1f6f75
2017-07-15 16:11:23 -07:00
Siying Dong d616ebea23 Add GPLv2 as an alternative license.
Summary: Closes https://github.com/facebook/rocksdb/pull/2226

Differential Revision: D4967547

Pulled By: siying

fbshipit-source-id: dd3b58ae1e7a106ab6bb6f37ab5c88575b125ab4
2017-04-27 18:06:12 -07:00
Maysam Yabandeh 4c9447d889 Add erase option to release cache
Summary:
This is useful when we put the entries in the block cache for accounting
purposes and do not expect it to be used after it is released. If the cache does not
erase the item in such cases not only the performance of cache is
negatively affected but the item's destructor not being called at the
time of release might violate the assumptions about the lifetime of the
object.

The new change adds a force_erase option to the Release method and
returns a boolean to indicate whehter the item is successfully deleted.
Closes https://github.com/facebook/rocksdb/pull/2180

Differential Revision: D4916032

Pulled By: maysamyabandeh

fbshipit-source-id: 94409a346069923cac9de8e57adc313b4ed46f28
2017-04-24 11:28:36 -07:00
Siying Dong d2dce5611a Move some files under util/ to separate dirs
Summary:
Move some files under util/ to new directories env/, monitoring/ options/ and cache/
Closes https://github.com/facebook/rocksdb/pull/2090

Differential Revision: D4833681

Pulled By: siying

fbshipit-source-id: 2fd8bef
2017-04-05 19:09:16 -07:00