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157 commits

Author SHA1 Message Date
Andrew Kryczka 5cf6ab6f31 Ran clang-format on db/ directory (#10910)
Summary:
Ran `find ./db/ -type f | xargs clang-format -i`. Excluded minor changes it tried to make on db/db_impl/. Everything else it changed was directly under db/ directory. Included minor manual touchups mentioned in PR commit history.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10910

Reviewed By: riversand963

Differential Revision: D40880683

Pulled By: ajkr

fbshipit-source-id: cfe26cda05b3fb9a72e3cb82c286e21d8c5c4174
2022-11-02 14:34:24 -07:00
Jay Zhuang a3acf2ef87 Add seqno to time mapping (#10338)
Summary:
Which will be used for tiered storage to preclude hot data from
compacting to the cold tier (the last level).
Internally, adding seqno to time mapping. A periodic_task is scheduled
to record the current_seqno -> current_time in certain cadence. When
memtable flush, the mapping informaiton is stored in sstable property.
During compaction, the mapping information are merged and get the
approximate time of sequence number, which is used to determine if a key
is recently inserted or not and preclude it from the last level if it's
recently inserted (within the `preclude_last_level_data_seconds`).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10338

Test Plan: CI

Reviewed By: siying

Differential Revision: D37810187

Pulled By: jay-zhuang

fbshipit-source-id: 6953be7a18a99de8b1cb3b162d712f79c2b4899f
2022-07-14 21:49:34 -07:00
Baptiste Lemaire 5879053fd0 Dynamically changeable MemPurge option (#10011)
Summary:
**Summary**
Make the mempurge option flag a Mutable Column Family option flag. Therefore, the mempurge feature can be dynamically toggled.

**Motivation**
RocksDB users prefer having the ability to switch features on and off without having to close and reopen the DB. This is particularly important if the feature causes issues and needs to be turned off. Dynamically changing a DB option flag does not seem currently possible.
Moreover, with this new change, the MemPurge feature can be toggled on or off independently between column families, which we see as a major improvement.

**Content of this PR**
This PR includes removal of the `experimental_mempurge_threshold` flag as a DB option flag, and its re-introduction as a `MutableCFOption` flag. I updated the code to handle dynamic changes of the flag (in particular inside the `FlushJob` file). Additionally, this PR includes a new test to demonstrate the capacity of the code to toggle the MemPurge feature on and off, as well as the addition in the `db_stress` module of 2 different mempurge threshold values (0.0 and 1.0) that can be randomly changed with the `set_option_one_in` flag. This is useful to stress test the dynamic changes.

**Benchmarking**
I will add numbers to prove that there is no performance impact within the next 12 hours.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10011

Reviewed By: pdillinger

Differential Revision: D36462357

Pulled By: bjlemaire

fbshipit-source-id: 5e3d63bdadf085c0572ecc2349e7dd9729ce1802
2022-06-23 09:42:18 -07:00
Bo Wang c073ed7601 Fix typo in comments and code (#10233)
Summary:
Fix typo in comments and code.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10233

Test Plan: Existing unit tests should pass.

Reviewed By: jay-zhuang, anand1976

Differential Revision: D37356702

Pulled By: gitbw95

fbshipit-source-id: 32c019adcc6dcc95a9882b38147a310091368e51
2022-06-22 15:45:21 -07:00
Gang Liao deff48bcef Add blob source to retrieve blobs in RocksDB (#10198)
Summary:
There is currently no caching mechanism for blobs, which is not ideal especially when the database resides on remote storage (where we cannot rely on the OS page cache). As part of this task, we would like to make it possible for the application to configure a blob cache.
In this task, we formally introduced the blob source to RocksDB.  BlobSource is a new abstraction layer that provides universal access to blobs, regardless of whether they are in the blob cache, secondary cache, or (remote) storage. Depending on user settings, it always fetch blobs from multi-tier cache and storage with minimal cost.

Note: The new `MultiGetBlob()` implementation is not included in the current PR. To go faster, we aim to create a separate PR for it in parallel!

This PR is a part of https://github.com/facebook/rocksdb/issues/10156

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10198

Reviewed By: ltamasi

Differential Revision: D37294735

Pulled By: gangliao

fbshipit-source-id: 9cb50422d9dd1bc03798501c2778b6c7520c7a1e
2022-06-20 20:58:11 -07:00
Hui Xiao d665afdbf3 Account memory of FileMetaData in global memory limit (#9924)
Summary:
**Context/Summary:**
As revealed by heap profiling, allocation of `FileMetaData` for [newly created file added to a Version](https://github.com/facebook/rocksdb/pull/9924/files#diff-a6aa385940793f95a2c5b39cc670bd440c4547fa54fd44622f756382d5e47e43R774) can consume significant heap memory. This PR is to account that toward our global memory limit based on block cache capacity.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9924

Test Plan:
- Previous `make check` verified there are only 2 places where the memory of  the allocated `FileMetaData` can be released
- New unit test `TEST_P(ChargeFileMetadataTestWithParam, Basic)`
- db bench (CPU cost of `charge_file_metadata` in write and compact)
   - **write micros/op: -0.24%** : `TEST_TMPDIR=/dev/shm/testdb ./db_bench -benchmarks=fillseq -db=$TEST_TMPDIR -charge_file_metadata=1 (remove this option for pre-PR) -disable_auto_compactions=1 -write_buffer_size=100000 -num=4000000 | egrep 'fillseq'`
   - **compact micros/op -0.87%** : `TEST_TMPDIR=/dev/shm/testdb ./db_bench -benchmarks=fillseq -db=$TEST_TMPDIR -charge_file_metadata=1 -disable_auto_compactions=1 -write_buffer_size=100000 -num=4000000 -numdistinct=1000 && ./db_bench -benchmarks=compact -db=$TEST_TMPDIR -use_existing_db=1 -charge_file_metadata=1 -disable_auto_compactions=1 | egrep 'compact'`

table 1 - write

#-run | (pre-PR) avg micros/op | std micros/op | (post-PR)  micros/op | std micros/op | change (%)
-- | -- | -- | -- | -- | --
10 | 3.9711 | 0.264408 | 3.9914 | 0.254563 | 0.5111933721
20 | 3.83905 | 0.0664488 | 3.8251 | 0.0695456 | -0.3633711465
40 | 3.86625 | 0.136669 | 3.8867 | 0.143765 | 0.5289363078
80 | 3.87828 | 0.119007 | 3.86791 | 0.115674 | **-0.2673865734**
160 | 3.87677 | 0.162231 | 3.86739 | 0.16663 | **-0.2419539978**

table 2 - compact

#-run | (pre-PR) avg micros/op | std micros/op | (post-PR)  micros/op | std micros/op | change (%)
-- | -- | -- | -- | -- | --
10 | 2,399,650.00 | 96,375.80 | 2,359,537.00 | 53,243.60 | -1.67
20 | 2,410,480.00 | 89,988.00 | 2,433,580.00 | 91,121.20 | 0.96
40 | 2.41E+06 | 121811 | 2.39E+06 | 131525 | **-0.96**
80 | 2.40E+06 | 134503 | 2.39E+06 | 108799 | **-0.78**

- stress test: `python3 tools/db_crashtest.py blackbox --charge_file_metadata=1  --cache_size=1` killed as normal

Reviewed By: ajkr

Differential Revision: D36055583

Pulled By: hx235

fbshipit-source-id: b60eab94707103cb1322cf815f05810ef0232625
2022-06-14 13:06:40 -07:00
Peter Dillinger efd035164b Meta-internal folly integration with F14FastMap (#9546)
Summary:
Especially after updating to C++17, I don't see a compelling case for
*requiring* any folly components in RocksDB. I was able to purge the existing
hard dependencies, and it can be quite difficult to strip out non-trivial components
from folly for use in RocksDB. (The prospect of doing that on F14 has changed
my mind on the best approach here.)

But this change creates an optional integration where we can plug in
components from folly at compile time, starting here with F14FastMap to replace
std::unordered_map when possible (probably no public APIs for example). I have
replaced the biggest CPU users of std::unordered_map with compile-time
pluggable UnorderedMap which will use F14FastMap when USE_FOLLY is set.
USE_FOLLY is always set in the Meta-internal buck build, and a simulation of
that is in the Makefile for public CI testing. A full folly build is not needed, but
checking out the full folly repo is much simpler for getting the dependency,
and anything else we might want to optionally integrate in the future.

Some picky details:
* I don't think the distributed mutex stuff is actually used, so it was easy to remove.
* I implemented an alternative to `folly::constexpr_log2` (which is much easier
in C++17 than C++11) so that I could pull out the hard dependencies on
`ConstexprMath.h`
* I had to add noexcept move constructors/operators to some types to make
F14's complainUnlessNothrowMoveAndDestroy check happy, and I added a
macro to make that easier in some common cases.
* Updated Meta-internal buck build to use folly F14Map (always)

No updates to HISTORY.md nor INSTALL.md as this is not (yet?) considered a
production integration for open source users.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9546

Test Plan:
CircleCI tests updated so that a couple of them use folly.

Most internal unit & stress/crash tests updated to use Meta-internal latest folly.
(Note: they should probably use buck but they currently use Makefile.)

Example performance improvement: when filter partitions are pinned in cache,
they are tracked by PartitionedFilterBlockReader::filter_map_ and we can build
a test that exercises that heavily. Build DB with

```
TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks=fillrandom -num=10000000 -disable_wal=1 -write_buffer_size=30000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -partition_index_and_filters
```

and test with (simultaneous runs with & without folly, ~20 times each to see
convergence)

```
TEST_TMPDIR=/dev/shm/rocksdb ./db_bench_folly -readonly -use_existing_db -benchmarks=readrandom -num=10000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -partition_index_and_filters -duration=40 -pin_l0_filter_and_index_blocks_in_cache
```

Average ops/s no folly: 26229.2
Average ops/s with folly: 26853.3 (+2.4%)

Reviewed By: ajkr

Differential Revision: D34181736

Pulled By: pdillinger

fbshipit-source-id: ffa6ad5104c2880321d8a1aa7187e00ab0d02e94
2022-04-13 07:34:01 -07:00
Peter Dillinger cad809978a Fix heap use-after-free race with DropColumnFamily (#9730)
Summary:
Although ColumnFamilySet comments say that DB mutex can be
freed during iteration, as long as you hold a ref while releasing DB
mutex, this is not quite true because UnrefAndTryDelete might delete cfd
right before it is needed to get ->next_ for the next iteration of the
loop.

This change solves the problem by making a wrapper class that makes such
iteration easier while handling the tricky details of UnrefAndTryDelete
on the previous cfd only after getting next_ in operator++.

FreeDeadColumnFamilies should already have been obsolete; this removes
it for good. Similarly, ColumnFamilySet::iterator doesn't need to check
for cfd with 0 refs, because those are immediately deleted.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9730

Test Plan:
was reported with ASAN on unit tests like
DBLogicalBlockSizeCacheTest.CreateColumnFamily (very rare); keep watching

Reviewed By: ltamasi

Differential Revision: D35038143

Pulled By: pdillinger

fbshipit-source-id: 0a5478d5be96c135343a00603711b7df43ae19c9
2022-03-24 13:05:17 -07:00
slk 95305c44a1 Add OpenAndTrimHistory API to support trimming data with specified timestamp (#9410)
Summary:
As disscussed in (https://github.com/facebook/rocksdb/issues/9223), Here added a new API  named DB::OpenAndTrimHistory, this API will open DB and trim data to the timestamp specofied by **trim_ts** (The data with newer timestamp than specified trim bound will be removed). This API should only be used at a timestamp-enabled db instance recovery.

And this PR implemented a new iterator named HistoryTrimmingIterator to support trimming history with a new API named DB::OpenAndTrimHistory. HistoryTrimmingIterator wrapped around the underlying InternalITerator such that keys whose timestamps newer than **trim_ts** should not be returned to the compaction iterator while **trim_ts** is not null.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9410

Reviewed By: ltamasi

Differential Revision: D34410207

Pulled By: riversand963

fbshipit-source-id: e54049dc234eccd673244c566b15df58df5a6236
2022-03-11 16:13:23 -08:00
Zhiyi Zhang 0cb0fc6fd3 Add DB properties for BlobDB (#8734)
Summary:
RocksDB exposes certain internal statistics via the DB property interface.
However, there are currently no properties related to BlobDB.

For starters, we would like to add the following BlobDB properties:
`rocksdb.num-blob-files`: number of blob files in the current Version (kind of like `num-files-at-level` but note this is not per level, since blob files are not part of the LSM tree).
`rocksdb.blob-stats`: this could return the total number and size of all blob files, and potentially also the total amount of garbage (in bytes) in the blob files in the current Version.
`rocksdb.total-blob-file-size`: the total size of all blob files (as a blob counterpart for `total-sst-file-size`) of all Versions.
`rocksdb.live-blob-file-size`: the total size of all blob files in the current Version.
`rocksdb.estimate-live-data-size`: this is actually an existing property that we can extend so it considers blob files as well. When it comes to blobs, we actually have an exact value for live bytes. Namely, live bytes can be computed simply as total bytes minus garbage bytes, summed over the entire set of blob files in the Version.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8734

Test Plan:
```
➜  rocksdb git:(new_feature_blobDB_properties) ./db_blob_basic_test
[==========] Running 16 tests from 2 test cases.
[----------] Global test environment set-up.
[----------] 10 tests from DBBlobBasicTest
[ RUN      ] DBBlobBasicTest.GetBlob
[       OK ] DBBlobBasicTest.GetBlob (12 ms)
[ RUN      ] DBBlobBasicTest.MultiGetBlobs
[       OK ] DBBlobBasicTest.MultiGetBlobs (11 ms)
[ RUN      ] DBBlobBasicTest.GetBlob_CorruptIndex
[       OK ] DBBlobBasicTest.GetBlob_CorruptIndex (10 ms)
[ RUN      ] DBBlobBasicTest.GetBlob_InlinedTTLIndex
[       OK ] DBBlobBasicTest.GetBlob_InlinedTTLIndex (12 ms)
[ RUN      ] DBBlobBasicTest.GetBlob_IndexWithInvalidFileNumber
[       OK ] DBBlobBasicTest.GetBlob_IndexWithInvalidFileNumber (9 ms)
[ RUN      ] DBBlobBasicTest.GenerateIOTracing
[       OK ] DBBlobBasicTest.GenerateIOTracing (11 ms)
[ RUN      ] DBBlobBasicTest.BestEffortsRecovery_MissingNewestBlobFile
[       OK ] DBBlobBasicTest.BestEffortsRecovery_MissingNewestBlobFile (13 ms)
[ RUN      ] DBBlobBasicTest.GetMergeBlobWithPut
[       OK ] DBBlobBasicTest.GetMergeBlobWithPut (11 ms)
[ RUN      ] DBBlobBasicTest.MultiGetMergeBlobWithPut
[       OK ] DBBlobBasicTest.MultiGetMergeBlobWithPut (14 ms)
[ RUN      ] DBBlobBasicTest.BlobDBProperties
[       OK ] DBBlobBasicTest.BlobDBProperties (21 ms)
[----------] 10 tests from DBBlobBasicTest (124 ms total)

[----------] 6 tests from DBBlobBasicTest/DBBlobBasicIOErrorTest
[ RUN      ] DBBlobBasicTest/DBBlobBasicIOErrorTest.GetBlob_IOError/0
[       OK ] DBBlobBasicTest/DBBlobBasicIOErrorTest.GetBlob_IOError/0 (12 ms)
[ RUN      ] DBBlobBasicTest/DBBlobBasicIOErrorTest.GetBlob_IOError/1
[       OK ] DBBlobBasicTest/DBBlobBasicIOErrorTest.GetBlob_IOError/1 (10 ms)
[ RUN      ] DBBlobBasicTest/DBBlobBasicIOErrorTest.MultiGetBlobs_IOError/0
[       OK ] DBBlobBasicTest/DBBlobBasicIOErrorTest.MultiGetBlobs_IOError/0 (10 ms)
[ RUN      ] DBBlobBasicTest/DBBlobBasicIOErrorTest.MultiGetBlobs_IOError/1
[       OK ] DBBlobBasicTest/DBBlobBasicIOErrorTest.MultiGetBlobs_IOError/1 (10 ms)
[ RUN      ] DBBlobBasicTest/DBBlobBasicIOErrorTest.CompactionFilterReadBlob_IOError/0
[       OK ] DBBlobBasicTest/DBBlobBasicIOErrorTest.CompactionFilterReadBlob_IOError/0 (1011 ms)
[ RUN      ] DBBlobBasicTest/DBBlobBasicIOErrorTest.CompactionFilterReadBlob_IOError/1
[       OK ] DBBlobBasicTest/DBBlobBasicIOErrorTest.CompactionFilterReadBlob_IOError/1 (1013 ms)
[----------] 6 tests from DBBlobBasicTest/DBBlobBasicIOErrorTest (2066 ms total)

[----------] Global test environment tear-down
[==========] 16 tests from 2 test cases ran. (2190 ms total)
[  PASSED  ] 16 tests.
```

Reviewed By: ltamasi

Differential Revision: D30690849

Pulled By: Zhiyi-Zhang

fbshipit-source-id: a7567319487ad76bd1a2e24bf143afdbbd9e4346
2021-09-08 12:22:04 -07:00
Levi Tamasi 3f7e929865 Fix a race in ColumnFamilyData::UnrefAndTryDelete (#8605)
Summary:
The `ColumnFamilyData::UnrefAndTryDelete` code currently on the trunk
unlocks the DB mutex before destroying the `ThreadLocalPtr` holding
the per-thread `SuperVersion` pointers when the only remaining reference
is the back reference from `super_version_`. The idea behind this was to
break the circular dependency between `ColumnFamilyData` and `SuperVersion`:
when the penultimate reference goes away, `ColumnFamilyData` can clean up
the `SuperVersion`, which can in turn clean up `ColumnFamilyData`. (Assuming there
is a `SuperVersion` and it is not referenced by anything else.) However,
unlocking the mutex throws a wrench in this plan by making it possible for another thread
to jump in and take another reference to the `ColumnFamilyData`, keeping the
object alive in a zombie `ThreadLocalPtr`-less state. This can cause issues like
https://github.com/facebook/rocksdb/issues/8440 ,
https://github.com/facebook/rocksdb/issues/8382 ,
and might also explain the `was_last_ref` assertion failures from the `ColumnFamilySet`
destructor we sometimes observe during close in our stress tests.

Digging through the archives, this unlocking goes way back to 2014 (or earlier). The original
rationale was that `SuperVersionUnrefHandle` used to lock the mutex so it can call
`SuperVersion::Cleanup`; however, this logic turned out to be deadlock-prone.
https://github.com/facebook/rocksdb/pull/3510 fixed the deadlock but left the
unlocking in place. https://github.com/facebook/rocksdb/pull/6147 then introduced
the circular dependency and associated cleanup logic described above (in order
to enable iterators to keep the `ColumnFamilyData` for dropped column families alive),
and moved the unlocking-relocking snippet to its present location in `UnrefAndTryDelete`.
Finally, https://github.com/facebook/rocksdb/pull/7749 fixed a memory leak but
apparently exacerbated the race by (otherwise correctly) switching to `UnrefAndTryDelete`
in `SuperVersion::Cleanup`.

The patch simply eliminates the unlocking and relocking, which has been unnecessary
ever since https://github.com/facebook/rocksdb/issues/3510 made `SuperVersionUnrefHandle` lock-free.
This closes the window during which another thread could increase the reference count,
and hopefully fixes the issues above.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8605

Test Plan: Ran `make check` and stress tests locally.

Reviewed By: pdillinger

Differential Revision: D30051035

Pulled By: ltamasi

fbshipit-source-id: 8fe559e4b4ad69fc142579f8bc393ef525918528
2021-08-02 18:12:11 -07:00
Peter Dillinger 74b7c0d249 Fix use-after-free on implicit temporary FileOptions (#8571)
Summary:
FileOptions has an implicit conversion from EnvOptions and some
internal APIs take `const FileOptions&` and save the reference, which is
counter to Google C++ guidelines,

> Avoid defining functions that require a const reference parameter to outlive the call, because const reference parameters bind to temporaries. Instead, find a way to eliminate the lifetime requirement (for example, by copying the parameter), or pass it by const pointer and document the lifetime and non-null requirements.

This is at least a problem for repair.cc, which passes an EnvOptions to
TableCache(), which would save a reference to the temporary copy as
FileOptions. This was unfortunately only caught as a side effect of
changes in https://github.com/facebook/rocksdb/issues/8544.

This change fixes the repair.cc case and updates the involved internal
APIs that save a reference to use `const FileOptions*` instead.

Unfortunately, I don't know how to get any of our sanitizers to reliably
report bugs like this, so I can't rule out more existing in our
codebase.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8571

Test Plan:
Test that issues seen with https://github.com/facebook/rocksdb/issues/8544 are fixed (can reproduce on
AWS EC2)

Reviewed By: ajkr

Differential Revision: D29943890

Pulled By: pdillinger

fbshipit-source-id: 95f9c5251548777b4dc994c1a083dd2add5799c9
2021-07-27 21:49:14 -07:00
Baptiste Lemaire c521a9ab2b Retire superfluous functions introduced in earlier mempurge PRs. (#8558)
Summary:
The main challenge to make the memtable garbage collection prototype (nicknamed `mempurge`) was to not get rid of WAL files that contain unflushed (but mempurged) data. That was successfully guaranteed by not writing the VersionEdit to the MANIFEST file after a successful mempurge.
By not writing VersionEdits to the `MANIFEST` file after a succesful mempurge operation, we do not change the earliest log file number that contains unflushed data: `cfd->GetLogNumber()` (`cfd->SetLogNumber()` is only called in `VersionSet::ProcessManifestWrites`). As a result, a number of functions introduced earlier just for the mempurge operation are not obscolete/redundant. (e.g.: `FlushJob::ExtractEarliestLogFileNumber`), and this PR aims at cleaning up all these now-unnecessary functions. In particular, we no longer need to store the earliest log file number in the `MemTable` struct itself. This PR therefore also reverts the `MemTable` struct to its original form.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8558

Test Plan: Already included in `db_flush_test.cc`.

Reviewed By: anand1976

Differential Revision: D29764351

Pulled By: bjlemaire

fbshipit-source-id: 0f43b260fa270251862512f397d3f24ee62e8437
2021-07-22 18:29:13 -07:00
Baptiste Lemaire 206845c057 Mempurge support for wal (#8528)
Summary:
In this PR, `mempurge` is made compatible with the Write Ahead Log: in case of recovery, the DB is now capable of recovering the data that was "mempurged" and kept in the `imm()` list of immutable memtables.
The twist was to add a uint64_t to the `memtable` struct to store the number of the earliest log file containing entries from the `memtable`. When a `Flush` operation is replaced with a `MemPurge`, the `VersionEdit` (which usually contains the new min log file number to pick up for recovery and the level 0 file path of the newly created SST file) is no longer appended to the manifest log, and every time the `deleteWal` method is called, a check is made on the list of immutable memtables.
This PR also includes a unit test that verifies that no data is lost upon Reopening of the database when the mempurge feature is activated. This extensive unit test includes two column families, with valid data contained in the imm() at time of "crash"/reopening (recovery).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8528

Reviewed By: pdillinger

Differential Revision: D29701097

Pulled By: bjlemaire

fbshipit-source-id: 072a900fb6ccc1edcf5eef6caf88f3060238edf9
2021-07-15 17:49:13 -07:00
Baptiste Lemaire 837705ad80 Make mempurge a background process (equivalent to in-memory compaction). (#8505)
Summary:
In https://github.com/facebook/rocksdb/issues/8454, I introduced a new process baptized `MemPurge` (memtable garbage collection). This new PR is built upon this past mempurge prototype.
In this PR, I made the `mempurge` process a background task, which provides superior performance since the mempurge process does not cling on the db_mutex anymore, and addresses severe restrictions from the past iteration (including a scenario where the past mempurge was failling, when a memtable was mempurged but was still referred to by an iterator/snapshot/...).
Now the mempurge process ressembles an in-memory compaction process: the stack of immutable memtables is filtered out, and the useful payload is used to populate an output memtable. If the output memtable is filled at more than 60% capacity (arbitrary heuristic) the mempurge process is aborted and a regular flush process takes place, else the output memtable is kept in the immutable memtable stack. Note that adding this output memtable to the `imm()` memtable stack does not trigger another flush process, so that the flush thread can go to sleep at the end of a successful mempurge.
MemPurge is activated by making the `experimental_allow_mempurge` flag `true`. When activated, the `MemPurge` process will always happen when the flush reason is `kWriteBufferFull`.
The 3 unit tests confirm that this process supports `Put`, `Get`, `Delete`, `DeleteRange` operators and is compatible with `Iterators` and `CompactionFilters`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8505

Reviewed By: pdillinger

Differential Revision: D29619283

Pulled By: bjlemaire

fbshipit-source-id: 8a99bee76b63a8211bff1a00e0ae32360aaece95
2021-07-09 17:23:59 -07:00
Baptiste Lemaire 9dc887ece0 Memtable "MemPurge" prototype (#8454)
Summary:
Implement an experimental feature called "MemPurge", which consists in purging "garbage" bytes out of a memtable and reuse the memtable struct instead of making it immutable and eventually flushing its content to storage.
The prototype is by default deactivated and is not intended for use. It is intended for correctness and validation testing. At the moment, the "MemPurge" feature can be switched on by using the `options.experimental_allow_mempurge` flag. For this early stage, when the allow_mempurge flag is set to `true`, all the flush operations will be rerouted to perform a MemPurge. This is a temporary design decision that will give us the time to explore meaningful heuristics to use MemPurge at the right time for relevant workloads . Moreover, the current MemPurge operation only supports `Puts`, `Deletes`, `DeleteRange` operations, and handles `Iterators` as well as `CompactionFilter`s that are invoked at flush time .
Three unit tests are added to `db_flush_test.cc` to test if MemPurge works correctly (and checks that the previously mentioned operations are fully supported thoroughly tested).
One noticeable design decision is the timing of the MemPurge operation in the memtable workflow: for this prototype, the mempurge happens when the memtable is switched (and usually made immutable). This is an inefficient process because it implies that the entirety of the MemPurge operation happens while holding the db_mutex. Future commits will make the MemPurge operation a background task (akin to the regular flush operation) and aim at drastically enhancing the performance of this operation. The MemPurge is also not fully "WAL-compatible" yet, but when the WAL is full, or when the regular MemPurge operation fails (or when the purged memtable still needs to be flushed), a regular flush operation takes place. Later commits will also correct these behaviors.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8454

Reviewed By: anand1976

Differential Revision: D29433971

Pulled By: bjlemaire

fbshipit-source-id: 6af48213554e35048a7e03816955100a80a26dc5
2021-07-02 05:23:02 -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
Levi Tamasi d83542ca83 Make it possible to apply only a subrange of table property collectors (#8298)
Summary:
This patch does two things:
1) Introduces some aliases in order to eliminate/prevent long-winded type names
w/r/t the internal table property collectors (see e.g.
`std::vector<std::unique_ptr<IntTblPropCollectorFactory>>`).
2) Makes it possible to apply only a subrange of table property collectors during
table building by turning `TableBuilderOptions::int_tbl_prop_collector_factories`
from a pointer to a `vector` into a range (i.e. a pair of iterators).

Rationale: I plan to introduce a BlobDB related table property collector, which
should only be applied during table creation if blob storage is enabled at the moment
(which can be changed dynamically). This change will make it possible to include/
exclude the BlobDB related collector as needed without having to introduce
a second `vector` of collectors in `ColumnFamilyData` with pretty much the same
contents.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8298

Test Plan: `make check`

Reviewed By: jay-zhuang

Differential Revision: D28430910

Pulled By: ltamasi

fbshipit-source-id: a81d28f2c59495865300f43deb2257d2e6977c8e
2021-05-17 18:28:39 -07:00
mrambacher 8948dc8524 Make ImmutableOptions struct that inherits from ImmutableCFOptions and ImmutableDBOptions (#8262)
Summary:
The ImmutableCFOptions contained a bunch of fields that belonged to the ImmutableDBOptions.  This change cleans that up by introducing an ImmutableOptions struct.  Following the pattern of Options struct, this class inherits from the DB and CFOption structs (of the Immutable form).

Only one structural change (the ImmutableCFOptions::fs was changed to a shared_ptr from a raw one) is in this PR.  All of the other changes involve moving the member variables from the ImmutableCFOptions into the ImmutableOptions and changing member variables or function parameters as required for compilation purposes.

Follow-on PRs may do a further clean-up of the code, such as renaming variables (such as "ImmutableOptions cf_options") and potentially eliminating un-needed function parameters (there is no longer a need to pass both an ImmutableDBOptions and an ImmutableOptions to a function).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8262

Reviewed By: pdillinger

Differential Revision: D28226540

Pulled By: mrambacher

fbshipit-source-id: 18ae71eadc879dedbe38b1eb8e6f9ff5c7147dbf
2021-05-05 14:00:17 -07:00
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
fanrui03 67d72fb5dc Fix checkpoint stuck (#7921)
Summary:
## 1. Bug description:

When RocksDB Checkpoint, it may be stuck in `WaitUntilFlushWouldNotStallWrites` method.

## 2. Simple analysis of the reasons:

### 2.1 Configuration parameters:

```yaml
Compaction Style : Universal

max_write_buffer_number : 4
min_write_buffer_number_to_merge : 3
```

Checkpoint is usually very fast. When the Checkpoint is executed, `WaitUntilFlushWouldNotStallWrites` is called. If there are 2 Immutable MemTables, which are less than `min_write_buffer_number_to_merge`, they will not be flushed. But will enter this code.

```c++
// method: GetWriteStallConditionAndCause
if (mutable_cf_options.max_write_buffer_number> 3 &&
              num_unflushed_memtables >=
                  mutable_cf_options.max_write_buffer_number-1) {
     return {WriteStallCondition::kDelayed, WriteStallCause::kMemtableLimit};
}
```

code link: fbed72f03c/db/column_family.cc (L847)

Checkpoint thought there was a FlushJob, but it didn't. So will always wait.

### 2.2 solution:

Increase the restriction: the `number of Immutable MemTable` >= `min_write_buffer_number_to_merge will wait`.

If there are other better solutions, you can correct me.

### 2.3 Code that can reproduce the problem:

https://github.com/1996fanrui/fanrui-learning/blob/flink-1.12/module-java/src/main/java/com/dream/rocksdb/RocksDBCheckpointStuck.java

## 3. Interesting point

This bug will be triggered only when `the number of sorted runs >= level0_file_num_compaction_trigger`.

Because there is a break in WaitUntilFlushWouldNotStallWrites.

```c++
if (cfd->imm()->NumNotFlushed() <
        cfd->ioptions()->min_write_buffer_number_to_merge &&
    vstorage->l0_delay_trigger_count() <
        mutable_cf_options.level0_file_num_compaction_trigger) {
  break;
}
```

code link: fbed72f03c/db/db_impl/db_impl_compaction_flush.cc (L1974)

Universal may have `l0_delay_trigger_count() >= level0_file_num_compaction_trigger`, so this bug is triggered.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7921

Reviewed By: jay-zhuang

Differential Revision: D26900559

Pulled By: ajkr

fbshipit-source-id: 133c1252dad7393753f04a47590b68c7d8e670df
2021-03-09 02:21:25 -08:00
Cheng Chang fbce7a3808 Track WAL obsoletion when updating empty CF's log number (#7781)
Summary:
In the write path, there is an optimization: when a new WAL is created during SwitchMemtable, we update the internal log number of the empty column families to the new WAL. `FindObsoleteFiles` marks a WAL as obsolete if the WAL's log number is less than `VersionSet::MinLogNumberWithUnflushedData`. After updating the empty column families' internal log number, `VersionSet::MinLogNumberWithUnflushedData` might change, so some WALs might become obsolete to be purged from disk.

For example, consider there are 3 column families: 0, 1, 2:
1. initially, all the column families' log number is 1;
2. write some data to cf0, and flush cf0, but the flush is pending;
3. now a new WAL 2 is created;
4. write data to cf1 and WAL 2, now cf0's log number is 1, cf1's log number is 2, cf2's log number is 2 (because cf1 and cf2 are empty, so their log numbers will be set to the highest log number);
5. now cf0's flush hasn't finished, flush cf1, a new WAL 3 is created, and cf1's flush finishes, now cf0's log number is 1, cf1's log number is 3, cf2's log number is 3, since WAL 1 still contains data for the unflushed cf0, no WAL can be deleted from disk;
6. now cf0's flush finishes, cf0's log number is 2 (because when cf0 was switching memtable, WAL 3 does not exist yet), cf1's log number is 3, cf2's log number is 3, so WAL 1 can be purged from disk now, but WAL 2 still cannot because `MinLogNumberToKeep()` is 2;
7. write data to cf2 and WAL 3, because cf0 is empty, its log number is updated to 3, so now cf0's log number is 3, cf1's log number is 3, cf2's log number is 3;
8. now if the background threads want to purge obsolete files from disk, WAL 2 can be purged because `MinLogNumberToKeep()` is 3. But there are only two flush results written to MANIFEST: the first is for flushing cf1, and the `MinLogNumberToKeep` is 1, the second is for flushing cf0, and the `MinLogNumberToKeep` is 2. So without this PR, if the DB crashes at this point and try to recover, `WalSet` will still expect WAL 2 to exist.

When WAL tracking is enabled, we assume WALs will only become obsolete after a flush result is written to MANIFEST in `MemtableList::TryInstallMemtableFlushResults` (or its atomic flush counterpart). The above situation breaks this assumption.

This PR tracks WAL obsoletion if necessary before updating the empty column families' log numbers.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7781

Test Plan:
watch existing tests and stress tests to pass.
`make -j48 blackbox_crash_test` on devserver

Reviewed By: ltamasi

Differential Revision: D25631695

Pulled By: cheng-chang

fbshipit-source-id: ca7fff967bdb42204b84226063d909893bc0a4ec
2020-12-18 21:34:36 -08:00
Peter Dillinger b1ee191405 Fix memory leak for ColumnFamily drop with live iterator (#7749)
Summary:
Uncommon bug seen by ASAN with
ColumnFamilyTest.LiveIteratorWithDroppedColumnFamily, if the last two
references to a ColumnFamilyData are both SuperVersions (during
InstallSuperVersion). The fix is to use UnrefAndTryDelete even in
SuperVersion::Cleanup but with a parameter to avoid re-entering Cleanup
on the same SuperVersion being cleaned up.

ColumnFamilyData::Unref is considered unsafe so removed.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7749

Test Plan: ./column_family_test --gtest_filter=*LiveIter* --gtest_repeat=100

Reviewed By: jay-zhuang

Differential Revision: D25354304

Pulled By: pdillinger

fbshipit-source-id: e78f3a3f67c40013b8432f31d0da8bec55c5321c
2020-12-11 11:18:21 -08:00
Yanqin Jin eee0af9af1 Add full_history_ts_low to column family (#7740)
Summary:
Following https://github.com/facebook/rocksdb/issues/7655 and https://github.com/facebook/rocksdb/issues/7657, this PR adds `full_history_ts_low_` to `ColumnFamilyData`.
`ColumnFamilyData::full_history_ts_low_` will be used to create `FlushJob` and `CompactionJob`.

`ColumnFamilyData::full_history_ts_low` is persisted to the MANIFEST file. An application can only
increase its value. Consider the following case:

>
> The database has a key at ts=950. `full_history_ts_low` is first set to 1000, and then a GC is triggered
> and cleans up all data older than 1000. If the application sets `full_history_ts_low` to 900 afterwards,
> and tries to read at ts=960, the key at 950 is not seen. From the perspective of the read, the result
> is hard to reason. For simplicity, we just do now allow decreasing full_history_ts_low for now.
>

During recovery, the value of `full_history_ts_low` is restored for each column family if applicable. Note that
version edits in the MANIFEST file for the same column family may have `full_history_ts_low` unsorted due
to the potential interleaving of `LogAndApply` calls. Only the max will be used to restore the state of the
column family.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7740

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D25296217

Pulled By: riversand963

fbshipit-source-id: 24acda1df8262cd7cfdc6ce7b0ec56438abe242a
2020-12-05 14:18:22 -08:00
Ramkumar Vadivelu 9a690a74e1 In ParseInternalKey(), include corrupt key info in Status (#7515)
Summary:
Fixes Issue https://github.com/facebook/rocksdb/issues/7497

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

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

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

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

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

Reviewed By: ajkr

Differential Revision: D24240264

Pulled By: ramvadiv

fbshipit-source-id: bc48f5d4475ac19d7713e16df37505b31aac42e7
2020-10-28 10:12:58 -07:00
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
Akanksha Mahajan 8e0df9050c Store FSRandomAccessPtr object in RandomAccessFileReader (#7192)
Summary:
Replace FSRandomAccessFile pointer with FSRandomAccessFilePtr
    object in RandomAccessFileReader.
    This new object wraps FSRandomAccessFile pointer.

    Objective: If tracing is enabled, FSRandomAccessFile Ptr returns
    FSRandomAccessFileTracingWrapper pointer that includes all necessary
    information in IORecord and calls underlying FileSystem and invokes
    IOTracer to dump that record in a binary file. If tracing is disabled
    then, underlying FileSystem pointer is returned directly.
    FSRandomAccessFilePtr wrapper class is added to bypass the FSRandomAccessFileWrapper when
    tracing is disabled.

    Test Plan: make check -j64

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7192

Reviewed By: anand1976

Differential Revision: D23356867

Pulled By: akankshamahajan15

fbshipit-source-id: 48f31168166a17a7444b40be44a9a9d4a5c7182c
2020-08-27 11:21:52 -07:00
Jay Zhuang b0c5ecd6b3 Make max_subcompactions dynamically changeable (#7159)
Summary:
Make `max-subcompactions` dynamically changeable by passing the `DBOption` to Compaction.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7159

Reviewed By: siying

Differential Revision: D22671238

Pulled By: jay-zhuang

fbshipit-source-id: 311ca9f6bb606965544d8708616d358cfed5be42
2020-07-22 18:32:52 -07:00
Yanqin Jin fb09ef05dc Attempt to recover from db with missing table files (#6334)
Summary:
There are situations when RocksDB tries to recover, but the db is in an inconsistent state due to SST files referenced in the MANIFEST being missing. In this case, previous RocksDB will just fail the recovery and return a non-ok status.
This PR enables another possibility. During recovery, RocksDB checks possible MANIFEST files, and try to recover to the most recent state without missing table file. `VersionSet::Recover()` applies version edits incrementally and "materializes" a version only when this version does not reference any missing table file. After processing the entire MANIFEST, the version created last will be the latest version.
`DBImpl::Recover()` calls `VersionSet::Recover()`. Afterwards, WAL replay will *not* be performed.
To use this capability, set `options.best_efforts_recovery = true` when opening the db. Best-efforts recovery is currently incompatible with atomic flush.

Test plan (on devserver):
```
$make check
$COMPILE_WITH_ASAN=1 make all && make check
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6334

Reviewed By: anand1976

Differential Revision: D19778960

Pulled By: riversand963

fbshipit-source-id: c27ea80f29bc952e7d3311ecf5ee9c54393b40a8
2020-03-20 19:30:48 -07:00
Cheng Chang 2d9efc9ab2 Cache result of GetLogicalBufferSize in Linux (#6457)
Summary:
In Linux, when reopening DB with many SST files, profiling shows that 100% system cpu time spent for a couple of seconds for `GetLogicalBufferSize`. This slows down MyRocks' recovery time when site is down.

This PR introduces two new APIs:
1. `Env::RegisterDbPaths` and `Env::UnregisterDbPaths` lets `DB` tell the env when it starts or stops using its database directories . The `PosixFileSystem` takes this opportunity to set up a cache from database directories to the corresponding logical block sizes.
2. `LogicalBlockSizeCache` is defined only for OS_LINUX to cache the logical block sizes.

Other modifications:
1. rename `logical buffer size` to `logical block size` to be consistent with Linux terms.
2. declare `GetLogicalBlockSize` in `PosixHelper` to expose it to `PosixFileSystem`.
3. change the functions `IOError` and `IOStatus` in `env/io_posix.h` to have external linkage since they are used in other translation units too.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6457

Test Plan:
1. A new unit test is added for `LogicalBlockSizeCache` in `env/io_posix_test.cc`.
2. A new integration test is added for `DB` operations related to the cache in `db/db_logical_block_size_cache_test.cc`.

`make check`

Differential Revision: D20131243

Pulled By: cheng-chang

fbshipit-source-id: 3077c50f8065c0bffb544d8f49fb10bba9408d04
2020-03-11 18:40:05 -07:00
Zhichao Cao 8d73137ae8 Replace Directory with FSDirectory in DB (#6468)
Summary:
In the current code base, we can use Directory from Env to manage directory (e.g, Fsync()). The PR https://github.com/facebook/rocksdb/issues/5761  introduce the File System as a new Env API. So we further replace the Directory class in DB with FSDirectory such that we can have more IO information from IOStatus returned by FSDirectory.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6468

Test Plan: pass make asan_check

Differential Revision: D20195261

Pulled By: zhichao-cao

fbshipit-source-id: 93962cb9436852bfcfb76e086d9e7babd461cbe1
2020-03-02 16:16:26 -08:00
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
sdong 36c504be17 Avoid create directory for every column families (#6358)
Summary:
A relatively recent regression causes for every CF, create and open directory is called for the DB directory, unless CF has a private directory. This doesn't scale well with large number of column families.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6358

Test Plan: Run all existing tests and see it pass. strace with db_bench --num_column_families and observe it doesn't open directory for number of column families.

Differential Revision: D19675141

fbshipit-source-id: da01d9216f1dae3f03d4064fbd88ce71245bd9be
2020-02-03 14:13:39 -08:00
解轶伦 39fcaf8246 delete superversions in BackgroundCallPurge (#6146)
Summary:
I found that CleanupSuperVersion() may block Get() for 30ms+ (per MemTable is 256MB).

Then I found "delete sv" in ~SuperVersion() takes the time.

The backtrace looks like this

DBImpl::GetImpl() -> DBImpl::ReturnAndCleanupSuperVersion() ->
DBImpl::CleanupSuperVersion() : delete sv; -> ~SuperVersion()

I think it's better to delete in a background thread,  please review it。
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6146

Differential Revision: D18972066

fbshipit-source-id: 0f7b0b70b9bb1e27ad6fc1c8a408fbbf237ae08c
2019-12-17 13:22:57 -08:00
anand76 afa2420c2b Introduce a new storage specific Env API (#5761)
Summary:
The current Env API encompasses both storage/file operations, as well as OS related operations. Most of the APIs return a Status, which does not have enough metadata about an error, such as whether its retry-able or not, scope (i.e fault domain) of the error etc., that may be required in order to properly handle a storage error. The file APIs also do not provide enough control over the IO SLA, such as timeout, prioritization, hinting about placement and redundancy etc.

This PR separates out the file/storage APIs from Env into a new FileSystem class. The APIs are updated to return an IOStatus with metadata about the error, as well as to take an IOOptions structure as input in order to allow more control over the IO.

The user can set both ```options.env``` and ```options.file_system``` to specify that RocksDB should use the former for OS related operations and the latter for storage operations. Internally, a ```CompositeEnvWrapper``` has been introduced that inherits from ```Env``` and redirects individual methods to either an ```Env``` implementation or the ```FileSystem``` as appropriate. When options are sanitized during ```DB::Open```, ```options.env``` is replaced with a newly allocated ```CompositeEnvWrapper``` instance if both env and file_system have been specified. This way, the rest of the RocksDB code can continue to function as before.

This PR also ports PosixEnv to the new API by splitting it into two - PosixEnv and PosixFileSystem. PosixEnv is defined as a sub-class of CompositeEnvWrapper, and threading/time functions are overridden with Posix specific implementations in order to avoid an extra level of indirection.

The ```CompositeEnvWrapper``` translates ```IOStatus``` return code to ```Status```, and sets the severity to ```kSoftError``` if the io_status is retryable. The error handling code in RocksDB can then recover the DB automatically.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5761

Differential Revision: D18868376

Pulled By: anand1976

fbshipit-source-id: 39efe18a162ea746fabac6360ff529baba48486f
2019-12-13 14:48:41 -08:00
Jermy Li c2029f9716 Support concurrent CF iteration and drop (#6147)
Summary:
It's easy to cause coredump when closing ColumnFamilyHandle with unreleased iterators, especially iterators release is controlled by java GC when using JNI.

This patch fixed concurrent CF iteration and drop, we let iterators(actually SuperVersion) hold a ColumnFamilyData reference to prevent the CF from being released too early.

fixed https://github.com/facebook/rocksdb/issues/5982
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6147

Differential Revision: D18926378

fbshipit-source-id: 1dff6d068c603d012b81446812368bfee95a5e15
2019-12-12 19:04:48 -08:00
sdong 4c74dba5fa Bump up memory order of ref counting of ColumnFamilyData (#5723)
Summary:
We see this TSAN warning:

WARNING: ThreadSanitizer: data race (pid=282806)
  Write of size 8 at 0x7b6c00000e38 by thread T16 (mutexes: write M1023578822185846136):
    #0 operator delete(void*) <null> (libtsan.so.0+0x0000000795f8)
    https://github.com/facebook/rocksdb/issues/1 rocksdb::DBImpl::BackgroundFlush(bool*, rocksdb::JobContext*, rocksdb::LogBuffer*, rocksdb::FlushReason*, rocksdb::Env::Priority) db/db_impl/db_impl_compaction_flush.cc:2202 (db_flush_test+0x00000060b462)
    https://github.com/facebook/rocksdb/issues/2 rocksdb::DBImpl::BackgroundCallFlush(rocksdb::Env::Priority) db/db_impl/db_impl_compaction_flush.cc:2226 (db_flush_test+0x00000060cbd8)
    https://github.com/facebook/rocksdb/issues/3 rocksdb::DBImpl::BGWorkFlush(void*) db/db_impl/db_impl_compaction_flush.cc:2073 (db_flush_test+0x00000060d5ac)
    ......

Previous atomic write of size 4 at 0x7b6c00000e38 by main thread:
    #0 __tsan_atomic32_fetch_sub <null> (libtsan.so.0+0x00000006d721)
    https://github.com/facebook/rocksdb/issues/1 std::__atomic_base<int>::fetch_sub(int, std::memory_order) /mnt/gvfs/third-party2/libgcc/c67031f0f739ac61575a061518d6ef5038f99f90/7.x/platform007/5620abc/include/c++/7.3.0/bits/atomic_base.h:524 (db_flush_test+0x0000005f9e38)
    https://github.com/facebook/rocksdb/issues/2 rocksdb::ColumnFamilyData::Unref() db/column_family.h:286 (db_flush_test+0x0000005f9e38)
    https://github.com/facebook/rocksdb/issues/3 rocksdb::DBImpl::FlushMemTable(rocksdb::ColumnFamilyData*, rocksdb::FlushOptions const&, rocksdb::FlushReason, bool) db/db_impl/db_impl_compaction_flush.cc:1624 (db_flush_test+0x0000005f9e38)
    https://github.com/facebook/rocksdb/issues/4 rocksdb::DBImpl::TEST_FlushMemTable(rocksdb::ColumnFamilyData*, rocksdb::FlushOptions const&) db/db_impl/db_impl_debug.cc:127 (db_flush_test+0x00000061ace9)
    https://github.com/facebook/rocksdb/issues/5 rocksdb::DBFlushTest_CFDropRaceWithWaitForFlushMemTables_Test::TestBody() db/db_flush_test.cc:320 (db_flush_test+0x0000004b44e5)
    https://github.com/facebook/rocksdb/issues/6 void testing::internal::HandleSehExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) third-party/gtest-1.7.0/fused-src/gtest/gtest-all.cc:3824 (db_flush_test+0x000000be2988)
    ......

It's still very clear the cause of the warning is because that TSAN treats results from relaxed atomic::fetch_sub() as non-atomic with the operation itself. We can make it more explicit by bumping up the order to CS.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5723

Test Plan: Run all existing test.

Differential Revision: D16908250

fbshipit-source-id: bf17d39ed19058372bdf97f6440a743f88153021
2019-08-20 10:34:33 -07:00
haoyuhuang bb4178066d Integrate block cache tracer into db_impl (#5433)
Summary:
This PR integrates the block cache tracer class into db_impl.cc.
db_impl.cc contains a member variable of AtomicBlockCacheTraceWriter class and passes its reference to the block_based_table_reader.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5433

Differential Revision: D15728016

Pulled By: HaoyuHuang

fbshipit-source-id: 23d5659e8c82d556833dcc1a5558aac8c1f7db71
2019-06-13 15:43:10 -07:00
Maysam Yabandeh ae05a83e19 Call ValidateOptions from SetOptions (#5368)
Summary:
Currently we validate options in DB::Open. However the validation step is missing when options are dynamically updated in ::SetOptions. The patch fixes that.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5368

Differential Revision: D15540101

Pulled By: maysamyabandeh

fbshipit-source-id: d27bbffd8f0252d1b50bcf59e0a70a278ed937f4
2019-06-03 19:49:57 -07:00
Siying Dong 596cc1547a Update comments in column_family.h (#5347)
Summary:
Document relationships of data structures declared in column_family.h
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5347

Differential Revision: D15496941

Pulled By: siying

fbshipit-source-id: 47b37835abba26aa31a94fabea6b2775483e0ccb
2019-05-24 12:07:15 -07:00
Zhongyi Xie baa5302447 Avoid double-compacting data in bottom level in manual compactions (#5138)
Summary:
Depending on the config, manual compaction (leveled compaction style) does following compactions:
L0->L1
L1->L2
...
Ln-1 -> Ln
Ln -> Ln
The final Ln -> Ln compaction is partly unnecessary as it recompacts all the files that were just generated by the Ln-1 -> Ln. We should avoid recompacting such files. This rule should be applied to Lmax only.
Resolves issue https://github.com/facebook/rocksdb/issues/4995
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5138

Differential Revision: D14940106

Pulled By: miasantreble

fbshipit-source-id: 8d3cf5507a17e76f3333cfd4bac5256d005636e5
2019-04-16 23:32:20 -07:00
Anand Ananthabhotla b9d6eccac1 Lock free MultiGet (#4754)
Summary:
Avoid locking the DB mutex in order to reference SuperVersions. Instead, we get the thread local cached SuperVersion for each column family in the list. It depends on finding a sequence number that overlaps with all the open memtables. We start with the latest published sequence number, and if any of the memtables is sealed before we can get all the SuperVersions, the process is repeated. After a few times, give up and lock the DB mutex.

Tests:
1. Unit tests
2. make check
3. db_bench -

TEST_TMPDIR=/dev/shm ./db_bench -use_existing_db=true -benchmarks=readrandom -write_buffer_size=4194304 -target_file_size_base=4194304 -max_bytes_for_level_base=16777216 -num=5000000 -reads=1000000 -threads=32 -compression_type=none -cache_size=1048576000 -batch_size=1 -bloom_bits=1
readrandom   :       0.167 micros/op 5983920 ops/sec;  426.2 MB/s (1000000 of 1000000 found)

Multireadrandom with batch size 1:
multireadrandom :       0.176 micros/op 5684033 ops/sec; (1000000 of 1000000 found)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4754

Differential Revision: D13363550

Pulled By: anand1976

fbshipit-source-id: 6243e8de7dbd9c8bb490a8eca385da0c855b1dd4
2019-01-02 11:42:54 -08:00
Huachao Huang ed7a95b28c Add max_subcompactions as a compaction option
Summary:
Sometimes we want to compact files as fast as possible, but don't want to set a large `max_subcompactions` in the `DBOptions` by default.
I add a `max_subcompactions` options to `CompactionOptions` so that we can choose a proper concurrency dynamically.
Closes https://github.com/facebook/rocksdb/pull/3775

Differential Revision: D7792357

Pulled By: ajkr

fbshipit-source-id: 94f54c3784dce69e40a229721a79a97e80cd6a6c
2018-04-27 11:57:39 -07:00
Yanqin Jin 7dfbe33532 Rename pending_compaction_ to queued_for_compaction_.
Summary:
We use `queued_for_flush_` to indicate a column family has been added to the
flush queue. Similarly and to be consistent in our naming, we need to use `queued_for_compaction_` to indicate a column family has been added to the compaction queue. In the past we used
`pending_compaction_` which can also be ambiguous.
Closes https://github.com/facebook/rocksdb/pull/3781

Differential Revision: D7790063

Pulled By: riversand963

fbshipit-source-id: 6786b11a4fcaea36dc9b4672233dbe042f921804
2018-04-27 11:12:01 -07:00
Yanqin Jin 513b5ce618 Rename pending_flush_ to queued_for_flush_.
Summary:
With ColumnFamilyData::pending_flush_, we have the following code snippet in DBImpl::ScheedulePendingFlush

```
if (!cfd->pending_flush() && cfd->imm()->IsFlushPending()) {
...
}
```

`Pending` is ambiguous, and I feel `queued_for_flush` is a better name,
especially for the sake of readability.
Closes https://github.com/facebook/rocksdb/pull/3777

Differential Revision: D7783066

Pulled By: riversand963

fbshipit-source-id: f1bd8c8bfe5eafd2c94da0d8566c9b2b6bb57229
2018-04-26 21:12:51 -07:00
Phani Shekhar Mantripragada 446b32cfc3 Support for Column family specific paths.
Summary:
In this change, an option to set different paths for different column families is added.
This option is set via cf_paths setting of ColumnFamilyOptions. This option will work in a similar fashion to db_paths setting. Cf_paths is a vector of Dbpath values which contains a pair of the absolute path and target size. Multiple levels in a Column family can go to different paths if cf_paths has more than one path.
To maintain backward compatibility, if cf_paths is not specified for a column family, db_paths setting will be used. Note that, if db_paths setting is also not specified, RocksDB already has code to use db_name as the only path.

Changes :
1) A new member "cf_paths" is added to ImmutableCfOptions. This is set, based on cf_paths setting of ColumnFamilyOptions and db_paths setting of ImmutableDbOptions.  This member is used to identify the path information whenever files are accessed.
2) Validation checks are added for cf_paths setting based on existing checks for db_paths setting.
3) DestroyDB, PurgeObsoleteFiles etc. are edited to support multiple cf_paths.
4) Unit tests are added appropriately.
Closes https://github.com/facebook/rocksdb/pull/3102

Differential Revision: D6951697

Pulled By: ajkr

fbshipit-source-id: 60d2262862b0a8fd6605b09ccb0da32bb331787d
2018-04-05 19:58:20 -07:00
Siying Dong 93d52696bf Memory Problem Of Destorying ColumnFamilyHandle after deleting the CF
Summary:
When destorying column family handle after the column family has been deleted, the handle may hold share pointers of some objects in ColumnFamilyOptions, but in the destructor, the destructing order may cause some of the objects to be destoryed before being used by the following steps. Fix it by making a copy of the option object and destory it as the last step.
Closes https://github.com/facebook/rocksdb/pull/3610

Differential Revision: D7281025

Pulled By: siying

fbshipit-source-id: ac18f3b2841788cba4ccfa1abd8d59158c1113bc
2018-03-20 17:13:12 -07:00
Yi Wu bf937cf15b Add "rocksdb.live-sst-files-size" DB property
Summary:
Add "rocksdb.live-sst-files-size" DB property which only include files of latest version. Existing "rocksdb.total-sst-files-size" include files from all versions and thus include files that's obsolete but not yet deleted. I'm going to use this new property to cap blob db sst + blob files size.
Closes https://github.com/facebook/rocksdb/pull/3548

Differential Revision: D7116939

Pulled By: yiwu-arbug

fbshipit-source-id: c6a52e45ce0f24ef78708156e1a923c1dd6bc79a
2018-03-01 18:01:10 -08:00
Andrew Kryczka 3ae0047278 skip CompactRange flush based on memtable contents
Summary:
CompactRange has a call to Flush because we guarantee that, at the time it's called, all existing keys in the range will be pushed through the user's compaction filter. However, previously the flush was done blindly, so it'd happen even if the memtable does not contain keys in the range specified by the user. This caused unnecessarily many L0 files to be created, leading to write stalls in some cases. This PR checks the memtable's contents, and decides to flush only if it overlaps with `CompactRange`'s range.

- Move the memtable overlap check logic from `ExternalSstFileIngestionJob` to `ColumnFamilyData::RangesOverlapWithMemtables`
- Reuse the above logic in `CompactRange` and skip flushing if no overlap
Closes https://github.com/facebook/rocksdb/pull/3520

Differential Revision: D7018897

Pulled By: ajkr

fbshipit-source-id: a3c6b1cfae56687b49dd89ccac7c948e53545934
2018-02-27 17:12:44 -08:00
Andrew Kryczka ee1c802675 Add delay before flush in CompactRange to avoid write stalling
Summary:
- Refactored logic for checking write stall condition to a helper function: `GetWriteStallConditionAndCause`. Now it is decoupled from the logic for updating WriteController / stats in `RecalculateWriteStallConditions`, so we can reuse it for predicting whether write stall will occur.
- Updated `CompactRange` to first check whether the one additional immutable memtable / L0 file would cause stalling before it flushes. If so, it waits until that is no longer true.
- Updated `bg_cv_` to be signaled on `SetOptions` calls. The stall conditions `CompactRange` cares about can change when (1) flush finishes, (2) compaction finishes, or (3) options dynamically change. The cv was already signaled for (1) and (2) but not yet for (3).
Closes https://github.com/facebook/rocksdb/pull/3381

Differential Revision: D6754983

Pulled By: ajkr

fbshipit-source-id: 5613e03f1524df7192dc6ae885d40fd8f091d972
2018-02-12 15:42:47 -08:00