Commit Graph

340 Commits

Author SHA1 Message Date
Yanqin Jin
50135c1bf3 Move HDFS support to separate repo (#9170)
Summary:
This PR moves HDFS support from RocksDB repo to a separate repo. The new (temporary?) repo
in this PR serves as an example before we finalize the decision on where and who to host hdfs support. At this point,
people can start from the example repo and fork.

Java/JNI is not included yet, and needs to be done later if necessary.

The goal is to include this commit in RocksDB 7.0 release.

Reference:
https://github.com/ajkr/dedupfs by ajkr

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9170

Test Plan:
Follow the instructions in https://github.com/riversand963/rocksdb-hdfs-env/blob/master/README.md. Build and run db_bench and db_stress.

make check

Reviewed By: ajkr

Differential Revision: D33751662

Pulled By: riversand963

fbshipit-source-id: 22b4db7f31762ed417a20239f5a08dcd1696244f
2022-01-24 20:23:54 -08:00
mrambacher
423538a816 Make MemoryAllocator into a Customizable class (#8980)
Summary:
- Make MemoryAllocator and its implementations into a Customizable class.
- Added a "DefaultMemoryAllocator" which uses new and delete
- Added a "CountedMemoryAllocator" that counts the number of allocs and free
- Updated the existing tests to use these new allocators
- Changed the memkind allocator test into a generic test that can test the various allocators.
- Added tests for creating all of the allocators
- Added tests to verify/create the JemallocNodumpAllocator using its options.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8980

Reviewed By: zhichao-cao

Differential Revision: D32990403

Pulled By: mrambacher

fbshipit-source-id: 6fdfe8218c10dd8dfef34344a08201be1fa95c76
2021-12-17 04:20:47 -08:00
Peter Dillinger
0050a73a4f New stable, fixed-length cache keys (#9126)
Summary:
This change standardizes on a new 16-byte cache key format for
block cache (incl compressed and secondary) and persistent cache (but
not table cache and row cache).

The goal is a really fast cache key with practically ideal stability and
uniqueness properties without external dependencies (e.g. from FileSystem).
A fixed key size of 16 bytes should enable future optimizations to the
concurrent hash table for block cache, which is a heavy CPU user /
bottleneck, but there appears to be measurable performance improvement
even with no changes to LRUCache.

This change replaces a lot of disjointed and ugly code handling cache
keys with calls to a simple, clean new internal API (cache_key.h).
(Preserving the old cache key logic under an option would be very ugly
and likely negate the performance gain of the new approach. Complete
replacement carries some inherent risk, but I think that's acceptable
with sufficient analysis and testing.)

The scheme for encoding new cache keys is complicated but explained
in cache_key.cc.

Also: EndianSwapValue is moved to math.h to be next to other bit
operations. (Explains some new include "math.h".) ReverseBits operation
added and unit tests added to hash_test for both.

Fixes https://github.com/facebook/rocksdb/issues/7405 (presuming a root cause)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9126

Test Plan:
### Basic correctness
Several tests needed updates to work with the new functionality, mostly
because we are no longer relying on filesystem for stable cache keys
so table builders & readers need more context info to agree on cache
keys. This functionality is so core, a huge number of existing tests
exercise the cache key functionality.

### Performance
Create db with
`TEST_TMPDIR=/dev/shm ./db_bench -bloom_bits=10 -benchmarks=fillrandom -num=3000000 -partition_index_and_filters`
And test performance with
`TEST_TMPDIR=/dev/shm ./db_bench -readonly -use_existing_db -bloom_bits=10 -benchmarks=readrandom -num=3000000 -duration=30 -cache_index_and_filter_blocks -cache_size=250000 -threads=4`
using DEBUG_LEVEL=0 and simultaneous before & after runs.
Before ops/sec, avg over 100 runs: 121924
After ops/sec, avg over 100 runs: 125385 (+2.8%)

### Collision probability
I have built a tool, ./cache_bench -stress_cache_key to broadly simulate host-wide cache activity
over many months, by making some pessimistic simplifying assumptions:
* Every generated file has a cache entry for every byte offset in the file (contiguous range of cache keys)
* All of every file is cached for its entire lifetime

We use a simple table with skewed address assignment and replacement on address collision
to simulate files coming & going, with quite a variance (super-Poisson) in ages. Some output
with `./cache_bench -stress_cache_key -sck_keep_bits=40`:

```
Total cache or DBs size: 32TiB  Writing 925.926 MiB/s or 76.2939TiB/day
Multiply by 9.22337e+18 to correct for simulation losses (but still assume whole file cached)
```

These come from default settings of 2.5M files per day of 32 MB each, and
`-sck_keep_bits=40` means that to represent a single file, we are only keeping 40 bits of
the 128-bit cache key.  With file size of 2\*\*25 contiguous keys (pessimistic), our simulation
is about 2\*\*(128-40-25) or about 9 billion billion times more prone to collision than reality.

More default assumptions, relatively pessimistic:
* 100 DBs in same process (doesn't matter much)
* Re-open DB in same process (new session ID related to old session ID) on average
every 100 files generated
* Restart process (all new session IDs unrelated to old) 24 times per day

After enough data, we get a result at the end:

```
(keep 40 bits)  17 collisions after 2 x 90 days, est 10.5882 days between (9.76592e+19 corrected)
```

If we believe the (pessimistic) simulation and the mathematical generalization, we would need to run a billion machines all for 97 billion days to expect a cache key collision. To help verify that our generalization ("corrected") is robust, we can make our simulation more precise with `-sck_keep_bits=41` and `42`, which takes more running time to get enough data:

```
(keep 41 bits)  16 collisions after 4 x 90 days, est 22.5 days between (1.03763e+20 corrected)
(keep 42 bits)  19 collisions after 10 x 90 days, est 47.3684 days between (1.09224e+20 corrected)
```

The generalized prediction still holds. With the `-sck_randomize` option, we can see that we are beating "random" cache keys (except offsets still non-randomized) by a modest amount (roughly 20x less collision prone than random), which should make us reasonably comfortable even in "degenerate" cases:

```
197 collisions after 1 x 90 days, est 0.456853 days between (4.21372e+18 corrected)
```

I've run other tests to validate other conditions behave as expected, never behaving "worse than random" unless we start chopping off structured data.

Reviewed By: zhichao-cao

Differential Revision: D33171746

Pulled By: pdillinger

fbshipit-source-id: f16a57e369ed37be5e7e33525ace848d0537c88f
2021-12-16 17:15:13 -08:00
Yanqin Jin
e05c2bb549 Stress test for RocksDB transactions (#8936)
Summary:
Current db_stress does not cover complex read-write transactions. Therefore, this PR adds
coverage for emulated MyRocks-style transactions in `MultiOpsTxnsStressTest`. To achieve this, we need:

- Add a new operation type 'customops' so that we can add new complex groups of operations, e.g. transactions involving multiple read-write operations.
- Implement three read-write transactions and two read-only ones to emulate MyRocks-style transactions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8936

Test Plan:
```
make check
./db_stress -test_multi_ops_txns -use_txn -clear_column_family_one_in=0 -column_families=1 -writepercent=0 -delpercent=0 -delrangepercent=0 -customopspercent=60 -readpercent=20 -prefixpercent=0 -iterpercent=20 -reopen=0 -ops_per_thread=100000
```

Next step is to add more configurability and refine input generation and result reporting, which will done in separate follow-up PRs.

Reviewed By: zhichao-cao

Differential Revision: D31071795

Pulled By: riversand963

fbshipit-source-id: 50d7c828346ec643311336b904848a1588a37006
2021-12-14 13:34:43 -08:00
Andrew Kryczka
ce42ae6ffd Fix Statistics in db_stress (#9260)
Summary:
The `Statistics` objects are meant to be shared across translation
units, but this was prevented by declaring them static. We need to
ensure they are defined once in the program. The effect is now
`StressTest::PrintStatistics()` can actually print statistics since it
now sees non-null values when `--statistics=1`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9260

Reviewed By: zhichao-cao

Differential Revision: D32910162

Pulled By: ajkr

fbshipit-source-id: c926d6f556177987bee5fa3cbc87597803b230ee
2021-12-07 16:24:22 -08:00
Levi Tamasi
dc5de45af8 Support readahead during compaction for blob files (#9187)
Summary:
The patch adds a new BlobDB configuration option `blob_compaction_readahead_size`
that can be used to enable prefetching data from blob files during compaction.
This is important when using storage with higher latencies like HDDs or remote filesystems.
If enabled, prefetching is used for all cases when blobs are read during compaction,
namely garbage collection, compaction filters (when the existing value has to be read from
a blob file), and `Merge` (when the value of the base `Put` is stored in a blob file).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9187

Test Plan: Ran `make check` and the stress/crash test.

Reviewed By: riversand963

Differential Revision: D32565512

Pulled By: ltamasi

fbshipit-source-id: 87be9cebc3aa01cc227bec6b5f64d827b8164f5d
2021-11-19 17:53:47 -08:00
anand76
78556c14dd Secondary cache error injection (#9002)
Summary:
Implement secondary cache error injection in db_stress.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9002

Reviewed By: zhichao-cao

Differential Revision: D31874896

Pulled By: anand1976

fbshipit-source-id: 8cf04c061a4a44efa0fe88423d05cade67b85f73
2021-11-08 10:27:27 -08:00
Peter Dillinger
ad5325a736 Experimental support for SST unique IDs (#8990)
Summary:
* New public header unique_id.h and function GetUniqueIdFromTableProperties
which computes a universally unique identifier based on table properties
of table files from recent RocksDB versions.
* Generation of DB session IDs is refactored so that they are
guaranteed unique in the lifetime of a process running RocksDB.
(SemiStructuredUniqueIdGen, new test included.) Along with file numbers,
this enables SST unique IDs to be guaranteed unique among SSTs generated
in a single process, and "better than random" between processes.
See https://github.com/pdillinger/unique_id
* In addition to public API producing 'external' unique IDs, there is a function
for producing 'internal' unique IDs, with functions for converting between the
two. In short, the external ID is "safe" for things people might do with it, and
the internal ID enables more "power user" features for the future. Specifically,
the external ID goes through a hashing layer so that any subset of bits in the
external ID can be used as a hash of the full ID, while also preserving
uniqueness guarantees in the first 128 bits (bijective both on first 128 bits
and on full 192 bits).

Intended follow-up:
* Use the internal unique IDs in cache keys. (Avoid conflicts with https://github.com/facebook/rocksdb/issues/8912) (The file offset can be XORed into
the third 64-bit value of the unique ID.)
* Publish the external unique IDs in FileStorageInfo (https://github.com/facebook/rocksdb/issues/8968)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8990

Test Plan:
Unit tests added, and checking of unique ids in stress test.
NOTE in stress test we do not generate nearly enough files to thoroughly
stress uniqueness, but the test trims off pieces of the ID to check for
uniqueness so that we can infer (with some assumptions) stronger
properties in the aggregate.

Reviewed By: zhichao-cao, mrambacher

Differential Revision: D31582865

Pulled By: pdillinger

fbshipit-source-id: 1f620c4c86af9abe2a8d177b9ccf2ad2b9f48243
2021-10-18 23:32:01 -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
Andrew Kryczka
559943cdc0 Refactor expected state in stress/crash test (#8913)
Summary:
This is a precursor refactoring to enable an upcoming feature: persistence failure correctness testing.

- Changed `--expected_values_path` to `--expected_values_dir` and migrated "db_crashtest.py" to use the new flag. For persistence failure correctness testing there are multiple possible correct states since unsynced data is allowed to be dropped. Making it possible to restore all these possible correct states will eventually involve files containing snapshots of expected values and DB trace files.
- The expected values directory is managed by an `ExpectedStateManager` instance. Managing expected state files is separated out of `SharedState` to prevent `SharedState` from becoming too complex when the new files and features (snapshotting, tracing, and restoring) are introduced.
- Migrated expected values file access/management out of `SharedState` into a separate class called `ExpectedState`. This is not exposed directly to the test but rather the `ExpectedState` for the latest values file is accessed via a pass-through API on `ExpectedStateManager`. This forces the test to always access the single latest `ExpectedState`.
- Changed the initialization of the latest expected values file to use a tempfile followed by rename, and also add cleanup logic for possible stranded tempfiles.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8913

Test Plan:
run in several ways; try to make sure it's not obviously broken.

- crashtest blackbox without TEST_TMPDIR
```
$ python3 tools/db_crashtest.py blackbox --simple --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --duration=120 --interval=10 --compression_type=none --blob_compression_type=none
```
- crashtest blackbox with TEST_TMPDIR
```
$ TEST_TMPDIR=/dev/shm python3 tools/db_crashtest.py blackbox --simple --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --duration=120 --interval=10 --compression_type=none --blob_compression_type=none
```
- crashtest whitebox with TEST_TMPDIR
```
$ TEST_TMPDIR=/dev/shm python3 tools/db_crashtest.py whitebox --simple --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --duration=120 --interval=10 --compression_type=none --blob_compression_type=none --random_kill_odd=88887
```
- db_stress without expected_values_dir
```
$ ./db_stress --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --ops_per_thread=10000 --clear_column_family_one_in=0 --destroy_db_initially=true
```
- db_stress with expected_values_dir and manual corruption
```
$ ./db_stress --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --ops_per_thread=10000 --clear_column_family_one_in=0 --destroy_db_initially=true --expected_values_dir=./
// modify one byte in "./LATEST.state"
$ ./db_stress --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --ops_per_thread=10000 --clear_column_family_one_in=0 --destroy_db_initially=false --expected_values_dir=./
...
Verification failed for column family 0 key 0000000000000000 (0): Value not found: NotFound:
...
```

Reviewed By: riversand963

Differential Revision: D30921951

Pulled By: ajkr

fbshipit-source-id: babfe218062e55d018c9b046536c0289fb78f41c
2021-09-28 14:13:33 -07:00
mrambacher
7fd68b7c39 Make WalFilter, SstPartitionerFactory, FileChecksumGenFactory, and TableProperties Customizable (#8638)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8638

Reviewed By: zhichao-cao

Differential Revision: D31024729

Pulled By: mrambacher

fbshipit-source-id: 954c04ccab0b8dee64050a27aadf78ed119106c0
2021-09-28 05:32:02 -07:00
Peter Dillinger
0ef88538c6 Improve support for using regexes (#8740)
Summary:
* Consolidate use of std::regex for testing to testharness.cc, to
minimize Facebook linters constantly flagging uses in non-production
code.
* Improve syntax and error messages for asserting some string matches a
regex in tests.
* Add a public Regex wrapper class to encapsulate existing usage in
ObjectRegistry.
* Remove unnecessary include <regex>
* Put warnings that use of Regex in production code could cause bad
performance or stack overflow.

Intended follow-up work:
* Replace std::regex with another underlying implementation like RE2
* Improve ObjectRegistry interface in terms of possibly confusing literal
string matching vs. regex and in terms of reporting invalid regex.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8740

Test Plan:
tests updated, basic unit test for public Regex, and some manual
testing of temporary changes to see example error messages:

utilities/backupable/backupable_db_test.cc:917: Failure
000010_1162373755_138626.blob (child.name)
does not match regex
[0-9]+_[0-9]+_[0-9]+[.]blobHAHAHA (pattern)

db/db_basic_test.cc:74: Failure
R3SHSBA8C4U0CIMV2ZB0 (sid3)
does not match regex [0-9A-Z]{20}HAHAHA

Reviewed By: mrambacher

Differential Revision: D30706246

Pulled By: pdillinger

fbshipit-source-id: ba845e8f563ccad39bdb58f44f04e9da8f78c3fd
2021-09-07 13:05:23 -07:00
Peter Dillinger
13ded69484 Built-in support for generating unique IDs, bug fix (#8708)
Summary:
Env::GenerateUniqueId() works fine on Windows and on POSIX
where /proc/sys/kernel/random/uuid exists. Our other implementation is
flawed and easily produces collision in a new multi-threaded test.
As we rely more heavily on DB session ID uniqueness, this becomes a
serious issue.

This change combines several individually suitable entropy sources
for reliable generation of random unique IDs, with goal of uniqueness
and portability, not cryptographic strength nor maximum speed.

Specifically:
* Moves code for getting UUIDs from the OS to port::GenerateRfcUuid
rather than in Env implementation details. Callers are now told whether
the operation fails or succeeds.
* Adds an internal API GenerateRawUniqueId for generating high-quality
128-bit unique identifiers, by combining entropy from three "tracks":
  * Lots of info from default Env like time, process id, and hostname.
  * std::random_device
  * port::GenerateRfcUuid (when working)
* Built-in implementations of Env::GenerateUniqueId() will now always
produce an RFC 4122 UUID string, either from platform-specific API or
by converting the output of GenerateRawUniqueId.

DB session IDs now use GenerateRawUniqueId while DB IDs (not as
critical) try to use port::GenerateRfcUuid but fall back on
GenerateRawUniqueId with conversion to an RFC 4122 UUID.

GenerateRawUniqueId is declared and defined under env/ rather than util/
or even port/ because of the Env dependency.

Likely follow-up: enhance GenerateRawUniqueId to be faster after the
first call and to guarantee uniqueness within the lifetime of a single
process (imparting the same property onto DB session IDs).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8708

Test Plan:
A new mini-stress test in env_test checks the various public
and internal APIs for uniqueness, including each track of
GenerateRawUniqueId individually. We can't hope to verify anywhere close
to 128 bits of entropy, but it can at least detect flaws as bad as the
old code. Serial execution of the new tests takes about 350 ms on
my machine.

Reviewed By: zhichao-cao, mrambacher

Differential Revision: D30563780

Pulled By: pdillinger

fbshipit-source-id: de4c9ff4b2f581cf784fcedb5f39f16e5185c364
2021-08-30 15:20:41 -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
Merlin Mao
d10801e983 Allow Replayer to report the results of TraceRecords. (#8657)
Summary:
`Replayer::Execute()` can directly returns the result (e.g, request latency, DB::Get() return code, returned value, etc.)
`Replayer::Replay()` reports the results via a callback function.

New interface:
`TraceRecordResult` in "rocksdb/trace_record_result.h".

`DBTest2.TraceAndReplay` and `DBTest2.TraceAndManualReplay` are updated accordingly.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8657

Reviewed By: ajkr

Differential Revision: D30290216

Pulled By: autopear

fbshipit-source-id: 3c8d4e6b180ec743de1a9d9dcaee86064c74f0d6
2021-08-18 17:06:14 -07:00
Merlin Mao
f58d276764 Make TraceRecord and Replayer public (#8611)
Summary:
New public interfaces:
`TraceRecord` and `TraceRecord::Handler`, available in "rocksdb/trace_record.h".
`Replayer`, available in `rocksdb/utilities/replayer.h`.

User can use `DB::NewDefaultReplayer()` to create a Replayer to auto/manual replay a trace file.

Unit tests:
- `./db_test2 --gtest_filter="DBTest2.TraceAndReplay"`: Updated with the internal API changes.
- `./db_test2 --gtest_filter="DBTest2.TraceAndManualReplay"`: New for manual replay.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8611

Reviewed By: ajkr

Differential Revision: D30266329

Pulled By: autopear

fbshipit-source-id: 1ecb3cbbedae0f6a67c18f0cc82e002b4d81b6f8
2021-08-11 19:32:46 -07:00
mrambacher
d057e8326d Make MergeOperator+CompactionFilter/Factory into Customizable Classes (#8481)
Summary:
- Changed MergeOperator, CompactionFilter, and CompactionFilterFactory into Customizable classes.
 - Added Options/Configurable/Object Registration for TTL and Cassandra variants
 - Changed the StringAppend MergeOperators to accept a string delimiter rather than a simple char.  Made the delimiter into a configurable option
 - Added tests for new functionality

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8481

Reviewed By: zhichao-cao

Differential Revision: D30136050

Pulled By: mrambacher

fbshipit-source-id: 271d1772835935b6773abaf018ee71e42f9491af
2021-08-06 08:27:25 -07:00
Jay Zhuang
5dd18a8d8e Add micro-benchmark support (#8493)
Summary:
Add google benchmark for microbench.
Add ribbon_bench for benchmark ribbon filter vs. other filters.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8493

Test Plan:
added test to CI
To run the benchmark on devhost:
Install benchmark: `$ sudo dnf install google-benchmark-devel`
Build and run:
`$ ROCKSDB_NO_FBCODE=1 DEBUG_LEVEL=0 make microbench`
or with cmake:
`$ mkdir build && cd build && cmake .. -DCMAKE_BUILD_TYPE=Release -DWITH_BENCHMARK=1 && make microbench`

Reviewed By: pdillinger

Differential Revision: D29589649

Pulled By: jay-zhuang

fbshipit-source-id: 8fed13b562bef4472f161ecacec1ab6b18911dff
2021-07-08 18:22:45 -07:00
Levi Tamasi
6adc39e1bf Add an internal iterator that can measure the inflow of blobs (#8443)
Summary:
Follow-up to https://github.com/facebook/rocksdb/issues/8426 .

The patch adds a new kind of `InternalIterator` that wraps another one and
passes each key-value encountered to `BlobGarbageMeter` as inflow.
This iterator will be used as an input iterator for compactions when the input
SSTs reference blob files.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8443

Test Plan: `make check`

Reviewed By: jay-zhuang

Differential Revision: D29311987

Pulled By: ltamasi

fbshipit-source-id: b4493b4c0c0c2e3c2ecc33c8969a5ef02de5d9d8
2021-06-23 10:25:47 -07:00
Levi Tamasi
065bea1587 Add a class for measuring the amount of garbage generated during compaction (#8426)
Summary:
This is part of an alternative approach to https://github.com/facebook/rocksdb/issues/8316.
Unlike that approach, this one relies on key-values getting processed one by one
during compaction, and does not involve persistence.

Specifically, the patch adds a class `BlobGarbageMeter` that can track the number
and total size of blobs in a (sub)compaction's input and output on a per-blob file
basis. This information can then be used to compute the amount of additional
garbage generated by the compaction for any given blob file by subtracting the
"outflow" from the "inflow."

Note: this patch only adds `BlobGarbageMeter` and associated unit tests. I plan to
hook up this class to the input and output of `CompactionIterator` in a subsequent PR.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8426

Test Plan: `make check`

Reviewed By: jay-zhuang

Differential Revision: D29242250

Pulled By: ltamasi

fbshipit-source-id: 597e50ad556540e413a50e804ba15bc044d809bb
2021-06-21 22:25:30 -07:00
Akanksha Mahajan
3897ce3125 Support for Merge in Integrated BlobDB with base values (#8292)
Summary:
This PR add support for Merge operation in Integrated BlobDB with base values(i.e DB::Put). Merged values can be retrieved through  DB::Get, DB::MultiGet, DB::GetMergeOperands and Iterator operation.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8292

Test Plan: Add new unit tests

Reviewed By: ltamasi

Differential Revision: D28415896

Pulled By: akankshamahajan15

fbshipit-source-id: e9b3478bef51d2f214fb88c31ed3c8d2f4a531ff
2021-06-10 12:58:37 -07:00
Levi Tamasi
db325a5904 Add a clipping internal iterator (#8327)
Summary:
Logically, subcompactions process a key range [start, end); however, the way
this is currently implemented is that the `CompactionIterator` for any given
subcompaction keeps processing key-values until it actually outputs a key that
is out of range, which is then discarded. Instead of doing this, the patch
introduces a new type of internal iterator called `ClippingIterator` which wraps
another internal iterator and "clips" its range of key-values so that any KVs
returned are strictly in the [start, end) interval. This does eliminate a (minor)
inefficiency by stopping processing in subcompactions exactly at the limit;
however, the main motivation is related to BlobDB: namely, we need this to be
able to measure the amount of garbage generated by a subcompaction
precisely and prevent off-by-one errors.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8327

Test Plan: `make check`

Reviewed By: siying

Differential Revision: D28761541

Pulled By: ltamasi

fbshipit-source-id: ee0e7229f04edabbc7bed5adb51771fbdc287f69
2021-06-09 15:41:16 -07:00
Jay Zhuang
3786181a90 Add remote compaction public API (#8300)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8300

Reviewed By: ajkr

Differential Revision: D28464726

Pulled By: jay-zhuang

fbshipit-source-id: 49e9f4fb791808a6cbf39a7b1a331373f645fc5e
2021-05-19 21:41:31 -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
sdong
c3ff14e2c1 Hint temperature of bottommost level files to FileSystem (#8222)
Summary:
As the first part of the effort of having placing different files on different storage types, this change introduces several things:
(1) An experimental interface in FileSystem that specify temperature to a new file created.
(2) A test FileSystemWrapper,  SimulatedHybridFileSystem, that simulates HDD for a file of "warm" temperature.
(3) A simple experimental feature ColumnFamilyOptions.bottommost_temperature. RocksDB would pass this value to FileSystem when creating any bottommost file.
(4) A db_bench parameter that applies the (2) and (3) to db_bench.

The motivation of the change is to introduce minimal changes that allow us to evolve tiered storage development.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8222

Test Plan:
./db_bench --benchmarks=fillrandom --write_buffer_size=2000000 -max_bytes_for_level_base=20000000  -level_compaction_dynamic_level_bytes --reads=100 -compaction_readahead_size=20000000 --reads=100000 -num=10000000

followed by

./db_bench --benchmarks=readrandom,stats --write_buffer_size=2000000 -max_bytes_for_level_base=20000000 -simulate_hybrid_fs_file=/tmp/warm_file_list -level_compaction_dynamic_level_bytes -compaction_readahead_size=20000000 --reads=500 --threads=16 -use_existing_db --num=10000000

and see results as expected.

Reviewed By: ajkr

Differential Revision: D28003028

fbshipit-source-id: 4724896d5205730227ba2f17c3fecb11261744ce
2021-05-03 13:34:04 -07:00
Akanksha Mahajan
596e9008e4 Stall writes in WriteBufferManager when memory_usage exceeds buffer_size (#7898)
Summary:
When WriteBufferManager is shared across DBs and column families
to maintain memory usage under a limit, OOMs have been observed when flush cannot
finish but writes continuously insert to memtables.
In order to avoid OOMs, when memory usage goes beyond buffer_limit_ and DBs tries to write,
this change will stall incoming writers until flush is completed and memory_usage
drops.

Design: Stall condition: When total memory usage exceeds WriteBufferManager::buffer_size_
(memory_usage() >= buffer_size_) WriterBufferManager::ShouldStall() returns true.

DBImpl first block incoming/future writers by calling write_thread_.BeginWriteStall()
(which adds dummy stall object to the writer's queue).
Then DB is blocked on a state State::Blocked (current write doesn't go
through). WBStallInterface object maintained by every DB instance is added to the queue of
WriteBufferManager.

If multiple DBs tries to write during this stall, they will also be
blocked when check WriteBufferManager::ShouldStall() returns true.

End Stall condition: When flush is finished and memory usage goes down, stall will end only if memory
waiting to be flushed is less than buffer_size/2. This lower limit will give time for flush
to complete and avoid continous stalling if memory usage remains close to buffer_size.

WriterBufferManager::EndWriteStall() is called,
which removes all instances from its queue and signal them to continue.
Their state is changed to State::Running and they are unblocked. DBImpl
then signal all incoming writers of that DB to continue by calling
write_thread_.EndWriteStall() (which removes dummy stall object from the
queue).

DB instance creates WBMStallInterface which is an interface to block and
signal DBs during stall.
When DB needs to be blocked or signalled by WriteBufferManager,
state_for_wbm_ state is changed accordingly (RUNNING or BLOCKED).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7898

Test Plan: Added a new test db/db_write_buffer_manager_test.cc

Reviewed By: anand1976

Differential Revision: D26093227

Pulled By: akankshamahajan15

fbshipit-source-id: 2bbd982a3fb7033f6de6153aa92a221249861aae
2021-04-21 13:54:02 -07:00
Xavier Deguillard
8972dd1ffa Add util/crc32c_arm64.cc to TARGETS (#8168)
Summary:
When compiling RocksDB with Buck for ARM64, the linker complains about missing crc32 symbols that are defined in the crc32c_arm64.cc file. Since this file wasn't included in the build this is totally expected

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8168

Test Plan:
The following no longer fails to link rocksdb:
  buck build mode/mac-xcode //eden/fs/service:edenfs#macosx-arm64

Reviewed By: zhichao-cao

Differential Revision: D27664627

Pulled By: xavierd

fbshipit-source-id: fb9d7a538599ee7a08882f87628731de6e641f8d
2021-04-12 10:57:56 -07:00
Peter Dillinger
879357fdb0 Make backups openable as read-only DBs (#8142)
Summary:
A current limitation of backups is that you don't know the
exact database state of when the backup was taken. With this new
feature, you can at least inspect the backup's DB state without
restoring it by opening it as a read-only DB.

Rather than add something like OpenAsReadOnlyDB to the BackupEngine API,
which would inhibit opening stackable DB implementations read-only
(if/when their APIs support it), we instead provide a DB name and Env
that can be used to open as a read-only DB.

Possible follow-up work:

* Add a version of GetBackupInfo for a single backup.
* Let CreateNewBackup return the BackupID of the newly-created backup.

Implementation details:

Refactored ChrootFileSystem to split off new base class RemapFileSystem,
which allows more general remapping of files. We use this base class to
implement BackupEngineImpl::RemapSharedFileSystem.

To minimize API impact, I decided to just add these fields `name_for_open`
and `env_for_open` to those set by GetBackupInfo when
include_file_details=true. Creating the RemapSharedFileSystem adds a bit
to the memory consumption, perhaps unnecessarily in some cases, but this
has been mitigated by (a) only initialize the RemapSharedFileSystem
lazily when GetBackupInfo with include_file_details=true is called, and
(b) using the existing `shared_ptr<FileInfo>` objects to hold most of the
mapping data.

To enhance API safety, RemapSharedFileSystem is wrapped by new
ReadOnlyFileSystem which rejects any attempts to write. This uncovered a
couple of places in which DB::OpenForReadOnly would write to the
filesystem, so I fixed these. Added a release note because this affects
logging.

Additional minor refactoring in backupable_db.cc to support the new
functionality.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8142

Test Plan:
new test (run with ASAN and UBSAN), added to stress test and
ran it for a while with amplified backup_one_in

Reviewed By: ajkr

Differential Revision: D27535408

Pulled By: pdillinger

fbshipit-source-id: 04666d310aa0261ef6b2385c43ca793ce1dfd148
2021-04-06 14:37:53 -07:00
Peter Dillinger
bd7ddf58cb Make tests "parallel" and "passing ASC" by default (#8146)
Summary:
New tests should by default be expected to be parallelizeable
and passing with ASSERT_STATUS_CHECKED. Thus, I'm changing those two
lists to exclusions rather than inclusions.

For the set of exclusions, I only listed things that currently failed
for me when attempting not to exclude, or had some other documented
reason. This marks many more tests as "parallel," which will potentially
cause some failures from self-interference, but we can address those as
they are discovered.

Also changed CircleCI ASC test to be parallelized; the easy way to do
that is to exclude building tests that don't pass ASC, which is now a
small set.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8146

Test Plan: Watch CI, etc.

Reviewed By: riversand963

Differential Revision: D27542782

Pulled By: pdillinger

fbshipit-source-id: bdd74bcd912a963ee33f3fc0d2cad2567dc7740f
2021-04-04 20:10:11 -07:00
Adam Retter
24b7ebee80 range_tree requires GNU libc on ppc64 (#8070)
Summary:
If the platform is ppc64 and the libc is not GNU libc, then we exclude the range_tree from compilation.

See https://jira.percona.com/browse/PS-7559

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8070

Reviewed By: jay-zhuang

Differential Revision: D27246004

Pulled By: mrambacher

fbshipit-source-id: 59d8433242ce7ce608988341becb4f83312445f5
2021-03-29 16:32:08 -07:00
Yanqin Jin
9f7c02dad5 Move compacted_db_impl.[c|h] to db/db_impl (#8082)
Summary:
As title. All core db implementations should stay in db_impl.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8082

Test Plan: make check

Reviewed By: ajkr

Differential Revision: D27211442

Pulled By: riversand963

fbshipit-source-id: e0953fde75064740e899aaff7989ff033b7f5232
2021-03-23 13:49:26 -07:00
Xiaopeng Zhang
c603f2f898 support getUsage and getPinnedUsage in JavaAPI for Cache (#7925)
Summary:
support getUsage and getPinnedUsage in JavaAPI for Cache
also fix a typo in LRUCacheTest.java that the highPriPoolRatio is not valid(set 5, I guess it means 0.05)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7925

Reviewed By: mrambacher

Differential Revision: D26900241

Pulled By: ajkr

fbshipit-source-id: 735d1e40a16fa8919c89c7c7154ba7f81208ec33
2021-03-17 09:30:33 -07:00
Yanqin Jin
85d4f2c8b3 Move a test file to a better location (#8054)
Summary:
As title.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8054

Test Plan: make check

Reviewed By: mrambacher

Differential Revision: D27017955

Pulled By: riversand963

fbshipit-source-id: 829497d507bc89afbe982f8a8cf3555e52fd7098
2021-03-15 15:03:27 -07:00
Peter Dillinger
4b18c46d10 Refactor: add LineFileReader and Status::MustCheck (#8026)
Summary:
Removed confusing, awkward, and undocumented internal API
ReadOneLine and replaced with very simple LineFileReader.

In refactoring backupable_db.cc, this has the side benefit of
removing the arbitrary cap on the size of backup metadata files.

Also added Status::MustCheck to make it easy to mark a Status as
"must check." Using this, I can ensure that after
LineFileReader::ReadLine returns false the caller checks GetStatus().

Also removed some excessive conditional compilation in status.h

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8026

Test Plan: added unit test, and running tests with ASSERT_STATUS_CHECKED

Reviewed By: mrambacher

Differential Revision: D26831687

Pulled By: pdillinger

fbshipit-source-id: ef749c265a7a26bb13cd44f6f0f97db2955f6f0f
2021-03-09 20:12:38 -08:00
Peter Dillinger
a8b3b9a20c Refine Ribbon configuration, improve testing, add Homogeneous (#7879)
Summary:
This change only affects non-schema-critical aspects of the production candidate Ribbon filter. Specifically, it refines choice of internal configuration parameters based on inputs. The changes are minor enough that the schema tests in bloom_test, some of which depend on this, are unaffected. There are also some minor optimizations and refactorings.

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

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

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

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

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

Test Plan: unit test updates included

Reviewed By: jay-zhuang

Differential Revision: D26371245

Pulled By: pdillinger

fbshipit-source-id: da6600d90a3785b99ad17a88b2a3027710b4ea3a
2021-02-26 08:50:42 -08:00
Yanqin Jin
cef4a6c49f Compaction filter support for (new) BlobDB (#7974)
Summary:
Allow applications to implement a custom compaction filter and pass it to BlobDB.

The compaction filter's custom logic can operate on blobs.
To do so, application needs to subclass `CompactionFilter` abstract class and implement `FilterV2()` method.
Optionally, a method called `ShouldFilterBlobByKey()` can be implemented if application's custom logic rely solely
on the key to make a decision without reading the blob, thus saving extra IO. Examples can be found in
db/blob/db_blob_compaction_test.cc.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7974

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D26509280

Pulled By: riversand963

fbshipit-source-id: 59f9ae5614c4359de32f4f2b16684193cc537b39
2021-02-25 16:32:35 -08:00
Akanksha Mahajan
46cf5fbfdd Extend VerifyFileChecksums API for blob files (#7979)
Summary:
Extend VerifyFileChecksums API to verify blob files in case of
use_file_checksum.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7979

Test Plan: New unit test db_blob_corruption_test

Reviewed By: ltamasi

Differential Revision: D26534040

Pulled By: akankshamahajan15

fbshipit-source-id: 7dc5951a3df9d265ea1265e0122b43c966856ade
2021-02-22 22:09:22 -08:00
Andrew Kryczka
78ee8564ad Integrity protection for live updates to WriteBatch (#7748)
Summary:
This PR adds the foundation classes for key-value integrity protection and the first use case: protecting live updates from the source buffers added to `WriteBatch` through the destination buffer in `MemTable`. The width of the protection info is not yet configurable -- only eight bytes per key is supported. This PR allows users to enable protection by constructing `WriteBatch` with `protection_bytes_per_key == 8`. It does not yet expose a way for users to get integrity protection via other write APIs (e.g., `Put()`, `Merge()`, `Delete()`, etc.).

The foundation classes (`ProtectionInfo.*`) embed the coverage info in their type, and provide `Protect.*()` and `Strip.*()` functions to navigate between types with different coverage. For making bytes per key configurable (for powers of two up to eight) in the future, these classes are templated on the unsigned integer type used to store the protection info. That integer contains the XOR'd result of hashes with independent seeds for all covered fields. For integer fields, the hash is computed on the raw unadjusted bytes, so the result is endian-dependent. The most significant bytes are truncated when the hash value (8 bytes) is wider than the protection integer.

When `WriteBatch` is constructed with `protection_bytes_per_key == 8`, we hold a `ProtectionInfoKVOTC` (i.e., one that covers key, value, optype aka `ValueType`, timestamp, and CF ID) for each entry added to the batch. The protection info is generated from the original buffers passed by the user, as well as the original metadata generated internally. When writing to memtable, each entry is transformed to a `ProtectionInfoKVOTS` (i.e., dropping coverage of CF ID and adding coverage of sequence number), since at that point we know the sequence number, and have already selected a memtable corresponding to a particular CF. This protection info is verified once the entry is encoded in the `MemTable` buffer.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7748

Test Plan:
- an integration test to verify a wide variety of single-byte changes to the encoded `MemTable` buffer are caught
- add to stress/crash test to verify it works in variety of configs/operations without intentional corruption
- [deferred] unit tests for `ProtectionInfo.*` classes for edge cases like KV swap, `SliceParts` and `Slice` APIs are interchangeable, etc.

Reviewed By: pdillinger

Differential Revision: D25754492

Pulled By: ajkr

fbshipit-source-id: e481bac6c03c2ab268be41359730f1ceb9964866
2021-01-29 12:18:58 -08:00
mrambacher
12f1137355 Add a SystemClock class to capture the time functions of an Env (#7858)
Summary:
Introduces and uses a SystemClock class to RocksDB.  This class contains the time-related functions of an Env and these functions can be redirected from the Env to the SystemClock.

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

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

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

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

Reviewed By: pdillinger

Differential Revision: D26006406

Pulled By: mrambacher

fbshipit-source-id: ed10a8abbdab7ff2e23d69d85bd25b3e7e899e90
2021-01-25 22:09:11 -08:00
Sergei Petrunia
daab7603f6 Range Locking: Implementation of range locking (#7506)
Summary:
Range Locking - an implementation based on the locktree library

- Add a RangeTreeLockManager and RangeTreeLockTracker which implement
  range locking using the locktree library.
- Point locks are handled as locks on single-point ranges.
- Add a unit test: range_locking_test

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7506

Reviewed By: akankshamahajan15

Differential Revision: D25320703

Pulled By: cheng-chang

fbshipit-source-id: f86347384b42ba2b0257d67eca0f45f806b69da7
2020-12-22 19:12:36 -08:00
Sergei Petrunia
98236fb10e LockTree library, originally from PerconaFT (#7753)
Summary:
To be used for implementing Range Locking.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7753

Reviewed By: zhichao-cao

Differential Revision: D25378980

Pulled By: cheng-chang

fbshipit-source-id: 801a9c5cd92a84654ca2586b73e8f69001e89320
2020-12-09 12:10:57 -08:00
mrambacher
c442f6809f Create a Customizable class to load classes and configurations (#6590)
Summary:
The Customizable class is an extension of the Configurable class and allows instances to be created by a name/ID.  Classes that extend customizable can define their Type (e.g. "TableFactory", "Cache") and  a method to instantiate them (TableFactory::CreateFromString).  Customizable objects can be registered with the ObjectRegistry and created dynamically.

Future PRs will make more types of objects extend Customizable.

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

Reviewed By: cheng-chang

Differential Revision: D24841553

Pulled By: zhichao-cao

fbshipit-source-id: d0c2132bd932e971cbfe2c908ca2e5db30c5e155
2020-11-11 15:10:41 -08:00
Peter Dillinger
25d54c799c Ribbon: initial (general) algorithms and basic unit test (#7491)
Summary:
This is intended as the first commit toward a near-optimal alternative to static Bloom filters for SSTs. Stephan Walzer and I have agreed upon the name "Ribbon" for a PHSF based on his linear system construction in "Efficient Gauss Elimination for Near-Quadratic Matrices with One Short Random Block per Row, with Applications" ("SGauss") and my much faster "on the fly" algorithm for gaussian elimination (or for this linear system, "banding"), which can be faster than peeling while also more compact and flexible. See util/ribbon_alg.h for more detailed introduction and background. RIBBON = Rapid Incremental Boolean Banding ON-the-fly

This commit just adds generic (templatized) core algorithms and a basic unit test showing some features, including the ability to construct structures within 2.5% space overhead vs. information theoretic lower bound. (Compare to cache-local Bloom filter's ~50% space overhead -> ~30% reduction anticipated.) This commit does not include the storage scheme necessary to make queries fast, especially for filter queries, nor fractional "result bits", but there is some description already and those implementations will come soon. Nor does this commit add FilterPolicy support, for use in SST files, but that will also come soon.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7491

Reviewed By: jay-zhuang

Differential Revision: D24517954

Pulled By: pdillinger

fbshipit-source-id: 0119ee597e250d7e0edd38ada2ba50d755606fa7
2020-10-25 20:44:49 -07:00
Cheng Chang
0ea7db768e Abstract out LockManager interface (#7532)
Summary:
In order to be able to introduce more locking protocols, we need to abstract out the locking subsystem in TransactionDB into a set of interfaces.

PR https://github.com/facebook/rocksdb/pull/7013 introduces interface `LockTracker`. This PR is a follow up to take the first step to abstract out a `LockManager` interface.

Further modifications to the interface may be needed when introducing the first implementation of range lock. But the idea here is to put the range lock implementation based on range tree under the `utilities/transactions/lock/range/range_tree`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7532

Test Plan: point_lock_manager_test

Reviewed By: ajkr

Differential Revision: D24238731

Pulled By: cheng-chang

fbshipit-source-id: 2a9458cd8b3fb008d9529dbc4d3b28c24631f463
2020-10-19 10:14:42 -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
Tomasz Posluszny
6528ecc800 Add event listeners to RocksJava (#7425)
Summary:
Allows adding event listeners in RocksJava.

* Adds listeners getter and setter in `Options` and `DBOptions` classes.
* Adds `EventListener` Java interface and base class for implementing custom event listener callbacks - `AbstractEventListener`, which has an underlying native callback class implementing C++ `EventListener` class.
* `AbstractEventListener` class has mechanism for selectively enabling its callback methods in order to prevent invoking Java method if it is not implemented. This decreases performance cost in case only subset of event listener callback methods is needed - the JNI code for remaining "no-op" callbacks is not executed.
* The code is covered by unit tests in `EventListenerTest.java`, there are also tests added for setting/getting listeners field in `OptionsTest.java` and `DBOptionsTest.java`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7425

Reviewed By: pdillinger

Differential Revision: D24063390

Pulled By: jay-zhuang

fbshipit-source-id: 508c359538983d6b765e70d9989c351794a944ee
2020-10-14 11:33:52 -07:00
Levi Tamasi
1f84611e5d Clean up BlobLogReader and rename it to BlobLogSequentialReader (#7517)
Summary:
The patch does some cleanup in and around the legacy `BlobLogReader` class:
* It renames the class to `BlobLogSequentialReader` to emphasize that it is for
sequentially iterating through blobs in a blob file, as opposed to doing random
point reads using `BlobIndex`es (which is `BlobFileReader`'s jurisdiction).
* It removes some dead code from the old BlobDB implementation that references
`BlobLogReader` (namely the method `BlobFile::OpenRandomAccessReader`).
* It cleans up some `#include`s and forward declarations.
* It fixes some incorrect/outdated comments related to the reader class.
* It adds a few assertions to the `Read` methods of the class.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7517

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D24172611

Pulled By: ltamasi

fbshipit-source-id: 43e2ae1eba5c3dd30c1070cb00f217edc45bd64f
2020-10-07 17:48:16 -07:00
Levi Tamasi
22655a398b Introduce a blob file reader class (#7461)
Summary:
The patch adds a class called `BlobFileReader` that can be used to retrieve blobs
using the information available in blob references (e.g. blob file number, offset, and
size). This will come in handy when implementing blob support for `Get`, `MultiGet`,
and iterators, and also for compaction/garbage collection.

When a `BlobFileReader` object is created (using the factory method `Create`),
it first checks whether the specified file is potentially valid by comparing the file
size against the combined size of the blob file header and footer (files smaller than
the threshold are considered malformed). Then, it opens the file, and reads and verifies
the header and footer. The verification involves magic number/CRC checks
as well as checking for unexpected header/footer fields, e.g. incorrect column family ID
or TTL blob files.

Blobs can be retrieved using `GetBlob`. `GetBlob` validates the offset and compression
type passed by the caller (because of the presence of the header and footer, the
specified offset cannot be too close to the start/end of the file; also, the compression type
has to match the one in the blob file header), and retrieves and potentially verifies and
uncompresses the blob. In particular, when `ReadOptions::verify_checksums` is set,
`BlobFileReader` reads the blob record header as well (as opposed to just the blob itself)
and verifies the key/value size, the key itself, as well as the CRC of the blob record header
and the key/value pair.

In addition, the patch exposes the compression type from `BlobIndex` (both using an
accessor and via `DebugString`), and adds a blob file read latency histogram to
`InternalStats` that can be used with `BlobFileReader`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7461

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D23999219

Pulled By: ltamasi

fbshipit-source-id: deb6b1160d251258b308d5156e2ec063c3e12e5e
2020-10-07 15:44:53 -07:00
Andrew Kryczka
1e00909730 Periodically flush info log out of application buffer (#7488)
Summary:
This PR schedules a background thread (shared across all DB instances)
to flush info log every ten seconds. This improves debuggability in case
of RocksDB hanging since it ensures the log messages leading up to the hang
will eventually become visible in the log.

The bulk of this PR is moving monitoring/stats_dump_scheduler* to db/periodic_work_scheduler*
and making the corresponding name changes since now the scheduler handles info
log flushing, not just stats dumping.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7488

Reviewed By: riversand963

Differential Revision: D24065165

Pulled By: ajkr

fbshipit-source-id: 339c47a0ff43b79fdbd055fbd9fefbb6f9d8d3b5
2020-10-01 19:14:14 -07:00