Commit Graph

134 Commits

Author SHA1 Message Date
Akanksha Mahajan 56463d443d Provide support for subcompactions with user-defined timestamps (#10344)
Summary:
The subcompaction logic currently picks file boundaries as subcompaction boundaries. This is not compatible with user-defined timestamps because of two issues.
Issue1: ReadOptions.iterate_lower_bound and ReadOptions.iterate_upper_bound contains timestamps which results in assertion failure as BlockBasedTableIterator expects bounds to be without timestamps. As result, because of wrong comparison end key is returned as user_key resulting in assertion failure.
Issue2: Since it might result in two keys that only differ by user timestamp getting processed by two different subcompactions (and thus two different CompactionIterator state machines), which in turn can cause data correction issues.

This PR provide support to reenable subcompactions with user-defined timestamps.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10344

Test Plan:
Added new unit test
- Without fix for Issue1 unit test MultipleSubCompactions fails with error:
```
db_with_timestamp_compaction_test: ./db/compaction/clipping_iterator.h:247: void rocksdb::ClippingIterat│
or::AssertBounds(): Assertion `!valid_ || !end_ || cmp_->Compare(key(), *end_) < 0' failed.
Received signal 6 (Aborted)                                                                             │
#0   /usr/local/fbcode/platform009/lib/libc.so.6(gsignal+0x100) [0x7f8fbbbfe530] db_with_timestamp_compaction_test: ./db/compaction/clipping_iterator.h:247: void rocksdb::ClippingIterator::AssertBounds(): Assertion `!valid_ || !end_ || cmp_->Compare(key(), *end_) < 0' failed.
Aborted (core dumped)
```
Ran stress test
`make crash_test_with_ts -j32`

Reviewed By: riversand963

Differential Revision: D38220841

Pulled By: akankshamahajan15

fbshipit-source-id: 5d5cae2bd37fcaeba1e77fce0a69070ad4158ccb
2022-07-31 11:39:16 -07:00
Zichen Zhu c945a9a664 Allow sufficient subcompactions under round-robin compaction priority (#10422)
Summary:
Allow sufficient subcompactions can be used when the number of input files is less than `max_subcompactions` under round-robin compaction priority.

Test Case:
Add `RoundRobinWithoutAdditionalResources` into `db_compaction_test`

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10422

Reviewed By: ajkr

Differential Revision: D38186545

Pulled By: littlepig2013

fbshipit-source-id: b8e5098306f1e5b9561dfafafc8300a38f7fe88e
2022-07-26 20:37:34 -07:00
Zichen Zhu 8860fc902a Support subcmpct using reserved resources for round-robin priority (#10341)
Summary:
Earlier implementation of round-robin priority can only pick one file at a time and disallows parallel compactions within the same level. In this PR, round-robin compaction policy will expand towards more input files with respecting some additional constraints, which are summarized as follows:
 * Constraint 1: We can only pick consecutive files
   - Constraint 1a: When a file is being compacted (or some input files are being compacted after expanding), we cannot choose it and have to stop choosing more files
   - Constraint 1b: When we reach the last file (with the largest keys), we cannot choose more files (the next file will be the first one with small keys)
 * Constraint 2: We should ensure the total compaction bytes (including the overlapped files from the next level) is no more than `mutable_cf_options_.max_compaction_bytes`
 * Constraint 3: We try our best to pick as many files as possible so that the post-compaction level size can be just less than `MaxBytesForLevel(start_level_)`
 * Constraint 4: If trivial move is allowed, we reuse the logic of `TryNonL0TrivialMove()` instead of expanding files with Constraint 3

More details can be found in `LevelCompactionBuilder::SetupOtherFilesWithRoundRobinExpansion()`.

The above optimization accelerates the process of moving the compaction cursor, in which the write-amp can be further reduced. While a large compaction may lead to high write stall, we break this large compaction into several subcompactions **regardless of** the `max_subcompactions` limit.  The number of subcompactions for round-robin compaction priority is determined through the following steps:
* Step 1: Initialized against `max_output_file_limit`, the number of input files in the start level, and also the range size limit `ranges.size()`
* Step 2: Call `AcquireSubcompactionResources()`when max subcompactions is not sufficient, but we may or may not obtain desired resources, additional number of resources is stored in `extra_num_subcompaction_threads_reserved_`). Subcompaction limit is changed and update `num_planned_subcompactions` with `GetSubcompactionLimit()`
* Step 3: Call `ShrinkSubcompactionResources()` to ensure extra resources can be released (extra resources may exist for round-robin compaction when the number of actual number of subcompactions is less than the number of planned subcompactions)

More details can be found in `CompactionJob::AcquireSubcompactionResources()`,`CompactionJob::ShrinkSubcompactionResources()`, and `CompactionJob::ReleaseSubcompactionResources()`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10341

Test Plan: Add `CompactionPriMultipleFilesRoundRobin[1-3]` unit test in `compaction_picker_test.cc` and `RoundRobinSubcompactionsAgainstResources.SubcompactionsUsingResources/[0-4]`, `RoundRobinSubcompactionsAgainstPressureToken.PressureTokenTest/[0-1]` in `db_compaction_test.cc`

Reviewed By: ajkr, hx235

Differential Revision: D37792644

Pulled By: littlepig2013

fbshipit-source-id: 7fecb7c4ffd97b34bbf6e3b760b2c35a772a0657
2022-07-24 11:12:44 -07:00
sdong 252bea405e Improve SubCompaction Partitioning (#10393)
Summary:
Unit tests still haven't been fixed. Also need to add more tests. But I ran some simple fillrandom db_bench and the partitioning feels reasonable.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10393

Test Plan:
1. Make sure existing tests pass. This should cover some basic sub compaction logic to be correct and the partitioning result is reasonable;
2. Add a new unit test to ApproximateKeyAnchors()
3. Run some db_bench with max_subcompaction = 4 and watch the compaction is indeed partitioned evenly.

Reviewed By: jay-zhuang

Differential Revision: D38043783

fbshipit-source-id: 085008e0f85f9b7c5abff7800307618320efb19f
2022-07-23 17:38:49 -07:00
Gang Liao ec4ebeff30 Support prepopulating/warming the blob cache (#10298)
Summary:
Many workloads have temporal locality, where recently written items are read back in a short period of time. When using remote file systems, this is inefficient since it involves network traffic and higher latencies. Because of this, we would like to support prepopulating the blob cache during flush.

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

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10298

Reviewed By: ltamasi

Differential Revision: D37908743

Pulled By: gangliao

fbshipit-source-id: 9feaed234bc719d38f0c02975c1ad19fa4bb37d1
2022-07-17 07:13:59 -07:00
Jay Zhuang faa0f9723c Tiered compaction: integrate Seqno time mapping with per key placement (#10370)
Summary:
Using the Sequence number to time mapping to decide if a key is hot or not in
compaction and place it in the corresponding level.

Note: the feature is not complete, level compaction will run indefinitely until
all penultimate level data is cold and small enough to not trigger compaction.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10370

Test Plan:
CI
* Run basic db_bench for universal compaction manually

Reviewed By: siying

Differential Revision: D37892338

Pulled By: jay-zhuang

fbshipit-source-id: 792bbd91b1ccc2f62b5d14c53118434bcaac4bbe
2022-07-15 19:01:30 -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
Jay Zhuang 6ce0b2ca34 Tiered Compaction: per key placement support (#9964)
Summary:
Support per_key_placement for last level compaction, which will
be used for tiered compaction.
* compaction iterator reports which level a key should output to;
* compaction get the output level information and check if it's safe to
  output the data to penultimate level;
* all compaction output files will be installed.
* extra internal compaction stats added for penultimate level.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9964

Test Plan:
* Unittest
* db_bench, no significate difference: https://gist.github.com/jay-zhuang/3645f8fb97ec0ab47c10704bb39fd6e4
* microbench manual compaction no significate difference: https://gist.github.com/jay-zhuang/ba679b3e89e24992615ee9eef310e6dd
* run the db_stress multiple times (not covering the new feature) looks good (internal: https://fburl.com/sandcastle/9w84pp2m)

Reviewed By: ajkr

Differential Revision: D36249494

Pulled By: jay-zhuang

fbshipit-source-id: a96da57c8031c1df83e4a7a8567b657a112b80a3
2022-07-13 20:54:49 -07:00
zczhu 8debfe2b21 Replace the output split key with its pointer in subcompaction (#10316)
Summary:
Earlier implementation of cutting the output files with a compact cursor under Round-Robin priority uses `Valid()` to determine if the `output_split_key` is valid in `ShouldStopBefore`. This contributes to excessive CPU computation, as pointed out by [this issue](https://github.com/facebook/rocksdb/issues/10315). In this PR, we change the type of `output_split_key` to be `InternalKey*` and set it as `nullptr` if it is not going to be used in `ShouldStopBefore`, `Valid()` condition checking can be avoided using that pointer.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10316

Reviewed By: ajkr

Differential Revision: D37661492

Pulled By: littlepig2013

fbshipit-source-id: 66ff1105f3378e5573d3a126fdaff9bb23b5498f
2022-07-06 16:19:45 -07:00
zczhu 4f51101d31 Remove compact cursor when split sub-compactions (#10289)
Summary:
In round-robin compaction priority, when splitting the compaction into sub-compactions, the earlier implementation takes into account the compact cursor to have full use of available sub-compactions. But this may result in unbalanced sub-compactions, so we remove this here.  The removal does not affect the cursor-based splitting mechanism within a sub-compaction, and thus the output files are still ensured to be split according to the cursor.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10289

Reviewed By: ajkr

Differential Revision: D37559091

Pulled By: littlepig2013

fbshipit-source-id: b8b45b99f63b09cf873f7f049bcb4ab13871fffc
2022-06-30 15:36:46 -07:00
zczhu 17a1d65e3a Cut output files at compaction cursors (#10227)
Summary:
The files behind the compaction cursor contain newer data than the files ahead of it. If a compaction writes a file that spans from before its output level’s cursor to after it, then data before the cursor will be contaminated with the old timestamp from the data after the cursor. To avoid this, we can split the output file into two – one entirely before the cursor and one entirely after the cursor. Note that, in rare cases, we **DO NOT** need to cut the file if it is a trivial move since the file will not be contaminated by older files. In such case, the compact cursor is not guaranteed to be the boundary of the file, but it does not hurt the round-robin selection process.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10227

Test Plan:
Add 'RoundRobinCutOutputAtCompactCursor' unit test in `db_compaction_test`

Task: [T122216351](https://www.internalfb.com/intern/tasks/?t=122216351)

Reviewed By: jay-zhuang

Differential Revision: D37388088

Pulled By: littlepig2013

fbshipit-source-id: 9246a6a084b6037b90d6ab3183ba4dfb75a3378d
2022-06-23 14:25:42 -07:00
zczhu 30141461f9 Add basic kRoundRobin compaction policy (#10107)
Summary:
Add `kRoundRobin` as a compaction priority. The implementation is as follows.

- Define a cursor as the smallest Internal key in the successor of the selected file. Add `vector<InternalKey> compact_cursor_` into `VersionStorageInfo` where each element (`InternalKey`) in `compact_cursor_` represents a cursor. In round-robin compaction policy, we just need to select the first file (assuming files are sorted) and also has the smallest InternalKey larger than/equal to the cursor. After a file is chosen, we create a new `Fsize` vector which puts the selected file is placed at the first position in `temp`, the next cursor is then updated as the smallest InternalKey in successor of the selected file (the above logic is implemented in `SortFileByRoundRobin`).
- After a compaction succeeds, typically `InstallCompactionResults()`, we choose the next cursor for the input level and save it to `edit`. When calling `LogAndApply`, we save the next cursor with its level into some local variable and finally apply the change to `vstorage` in `SaveTo` function.
- Cursors are persist pair by pair (<level, InternalKey>) in `EncodeTo` so that they can be reconstructed when reopening. An empty cursor will not be encoded to MANIFEST

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10107

Test Plan: add unit test (`CompactionPriRoundRobin`) in `compaction_picker_test`, add `kRoundRobin` priority in `CompactionPriTest` from `db_compaction_test`, and add `PersistRoundRobinCompactCursor` in `db_compaction_test`

Reviewed By: ajkr

Differential Revision: D37316037

Pulled By: littlepig2013

fbshipit-source-id: 9f481748190ace416079139044e00df2968fb1ee
2022-06-21 11:56:53 -07:00
zczhu 3ee6c9baec Consolidate manual_compaction_paused_ check (#10070)
Summary:
As pointed out by [https://github.com/facebook/rocksdb/pull/8351#discussion_r645765422](https://github.com/facebook/rocksdb/pull/8351#discussion_r645765422), check `manual_compaction_paused` and `manual_compaction_canceled` can be reduced by setting `*canceled` to be true in `DisableManualCompaction()` and `*canceled` to be false in the last time calling `EnableManualCompaction()`.

Changed Tests: The origin `DBTest2.PausingManualCompaction1` uses a callback function to increase `manual_compaction_paused` and the origin CompactionJob/CompactionIterator with `manual_compaction_paused` can detect this. I changed the callback function so that it sets `*canceled` as true if `canceled` is not `nullptr` (to notify CompactionJob/CompactionIterator the compaction has been canceled).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10070

Test Plan: This change does not introduce new features, but some slight difference in compaction implementation. Run the same manual compaction unit tests as before (e.g., PausingManualCompaction[1-4], CancelManualCompaction[1-2], CancelManualCompactionWithListener in db_test2, and db_compaction_test).

Reviewed By: ajkr

Differential Revision: D36949133

Pulled By: littlepig2013

fbshipit-source-id: c5dc4c956fbf8f624003a0f5ad2690240063a821
2022-06-06 18:32:26 -07:00
Gang Liao e6432dfd4c Make it possible to enable blob files starting from a certain LSM tree level (#10077)
Summary:
Currently, if blob files are enabled (i.e. `enable_blob_files` is true), large values are extracted both during flush/recovery (when SST files are written into level 0 of the LSM tree) and during compaction into any LSM tree level. For certain use cases that have a mix of short-lived and long-lived values, it might make sense to support extracting large values only during compactions whose output level is greater than or equal to a specified LSM tree level (e.g. compactions into L1/L2/... or above). This could reduce the space amplification caused by large values that are turned into garbage shortly after being written at the price of some write amplification incurred by long-lived values whose extraction to blob files is delayed.

In order to achieve this, we would like to do the following:
- Add a new configuration option `blob_file_starting_level` (default: 0) to `AdvancedColumnFamilyOptions` (and `MutableCFOptions` and extend the related logic)
- Instantiate `BlobFileBuilder` in `BuildTable` (used during flush and recovery, where the LSM tree level is L0) and `CompactionJob` iff `enable_blob_files` is set and the LSM tree level is `>= blob_file_starting_level`
- Add unit tests for the new functionality, and add the new option to our stress tests (`db_stress` and `db_crashtest.py` )
- Add the new option to our benchmarking tool `db_bench` and the BlobDB benchmark script `run_blob_bench.sh`
- Add the new option to the `ldb` tool (see https://github.com/facebook/rocksdb/wiki/Administration-and-Data-Access-Tool)
- Ideally extend the C and Java bindings with the new option
- Update the BlobDB wiki to document the new option.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10077

Reviewed By: ltamasi

Differential Revision: D36884156

Pulled By: gangliao

fbshipit-source-id: 942bab025f04633edca8564ed64791cb5e31627d
2022-06-02 20:04:33 -07:00
sdong bea5831bff Move three info logging within DB Mutex to use log buffer (#10029)
Summary:
info logging with DB Mutex could potentially invoke I/O and cause performance issues. Move three of the cases to use log buffer.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10029

Test Plan: Run existing tests.

Reviewed By: jay-zhuang

Differential Revision: D36561694

fbshipit-source-id: cabb93fea299001a6b4c2802fcba3fde27fa062c
2022-05-23 10:09:37 -07:00
Jay Zhuang c6d326d3d7 Track SST unique id in MANIFEST and verify (#9990)
Summary:
Start tracking SST unique id in MANIFEST, which is used to verify with
SST properties to make sure the SST file is not overwritten or
misplaced. A DB option `try_verify_sst_unique_id` is introduced to
enable/disable the verification, if enabled, it opens all SST files
during DB-open to read the unique_id from table properties (default is
false), so it's recommended to use it with `max_open_files = -1` to
pre-open the files.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9990

Test Plan: unittests, format-compatible test, mini-crash

Reviewed By: anand1976

Differential Revision: D36381863

Pulled By: jay-zhuang

fbshipit-source-id: 89ea2eb6b35ed3e80ead9c724eb096083eaba63f
2022-05-19 11:04:21 -07:00
gitbw95 4da34b97ee Set Read rate limiter priority dynamically and pass it to FS (#9996)
Summary:
### Context:
Background compactions and flush generate large reads and writes, and can be long running, especially for universal compaction. In some cases, this can impact foreground reads and writes by users.

### Solution
User, Flush, and Compaction reads share some code path. For this task, we update the rate_limiter_priority in ReadOptions for code paths (e.g. FindTable (mainly in BlockBasedTable::Open()) and various iterators), and eventually update the rate_limiter_priority in IOOptions for FSRandomAccessFile.

**This PR is for the Read path.** The **Read:** dynamic priority for different state are listed as follows:

| State | Normal | Delayed | Stalled |
| ----- | ------ | ------- | ------- |
|  Flush (verification read in BuildTable()) | IO_USER | IO_USER | IO_USER |
|  Compaction | IO_LOW  | IO_USER | IO_USER |
|  User | User provided | User provided | User provided |

We will respect the read_options that the user provided and will not set it.
The only sst read for Flush is the verification read in BuildTable(). It claims to be "regard as user read".

**Details**
1. Set read_options.rate_limiter_priority dynamically:
- User: Do not update the read_options. Use the read_options that the user provided.
- Compaction: Update read_options in CompactionJob::ProcessKeyValueCompaction().
- Flush: Update read_options in BuildTable().

2. Pass the rate limiter priority to FSRandomAccessFile functions:
- After calling the FindTable(), read_options is passed through GetTableReader(table_cache.cc), BlockBasedTableFactory::NewTableReader(block_based_table_factory.cc), and BlockBasedTable::Open(). The Open() needs some updates for the ReadOptions variable and the updates are also needed for the called functions,  including PrefetchTail(), PrepareIOOptions(), ReadFooterFromFile(), ReadMetaIndexblock(), ReadPropertiesBlock(), PrefetchIndexAndFilterBlocks(), and ReadRangeDelBlock().
- In RandomAccessFileReader, the functions to be updated include Read(), MultiRead(), ReadAsync(), and Prefetch().
- Update the downstream functions of NewIndexIterator(), NewDataBlockIterator(), and BlockBasedTableIterator().

### Test Plans
Add unit tests.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9996

Reviewed By: anand1976

Differential Revision: D36452483

Pulled By: gitbw95

fbshipit-source-id: 60978204a4f849bb9261cb78d9bc1cb56d6008cf
2022-05-18 19:41:44 -07:00
gitbw95 05c678e135 Set Write rate limiter priority dynamically and pass it to FS (#9988)
Summary:
### Context:
Background compactions and flush generate large reads and writes, and can be long running, especially for universal compaction. In some cases, this can impact foreground reads and writes by users.

From the RocksDB perspective, there can be two kinds of rate limiters, the internal (native) one and the external one.
- The internal (native) rate limiter is introduced in [the wiki](https://github.com/facebook/rocksdb/wiki/Rate-Limiter). Currently, only IO_LOW and IO_HIGH are used and they are set statically.
- For the external rate limiter, in FSWritableFile functions,  IOOptions is open for end users to set and get rate_limiter_priority for their own rate limiter. Currently, RocksDB doesn’t pass the rate_limiter_priority through IOOptions to the file system.

### Solution
During the User Read, Flush write, Compaction read/write, the WriteController is used to determine whether DB writes are stalled or slowed down. The rate limiter priority (Env::IOPriority) can be determined accordingly. We decided to always pass the priority in IOOptions. What the file system does with it should be a contract between the user and the file system. We would like to set the rate limiter priority at file level, since the Flush/Compaction job level may be too coarse with multiple files and block IO level is too granular.

**This PR is for the Write path.** The **Write:** dynamic priority for different state are listed as follows:

| State | Normal | Delayed | Stalled |
| ----- | ------ | ------- | ------- |
|  Flush | IO_HIGH | IO_USER | IO_USER |
|  Compaction | IO_LOW | IO_USER | IO_USER |

Flush and Compaction writes share the same call path through BlockBaseTableWriter, WritableFileWriter, and FSWritableFile. When a new FSWritableFile object is created, its io_priority_ can be set dynamically based on the state of the WriteController. In WritableFileWriter, before the call sites of FSWritableFile functions, WritableFileWriter::DecideRateLimiterPriority() determines the rate_limiter_priority. The options (IOOptions) argument of FSWritableFile functions will be updated with the rate_limiter_priority.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9988

Test Plan: Add unit tests.

Reviewed By: anand1976

Differential Revision: D36395159

Pulled By: gitbw95

fbshipit-source-id: a7c82fc29759139a1a07ec46c37dbf7e753474cf
2022-05-18 00:41:41 -07:00
Yanqin Jin 3f263ef536 Add a temporary option for user to opt-out enforcement of SingleDelete contract (#9983)
Summary:
PR https://github.com/facebook/rocksdb/issues/9888 started to enforce the contract of single delete described in https://github.com/facebook/rocksdb/wiki/Single-Delete.

For some of existing use cases, it is desirable to have a transition during which compaction will not fail
if the contract is violated. Therefore, we add a temporary option `enforce_single_del_contracts` to allow
application to opt out from this new strict behavior. Once transition completes, the flag can be set to `true` again.

In a future release, the option will be removed.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9983

Test Plan: make check

Reviewed By: ajkr

Differential Revision: D36333672

Pulled By: riversand963

fbshipit-source-id: dcb703ea0ed08076a1422f1bfb9914afe3c2caa2
2022-05-16 15:44:59 -07:00
mrambacher bfc6a8ee4a Option type info functions (#9411)
Summary:
Add methods to set the various functions (Parse, Serialize, Equals) to the OptionTypeInfo.  These methods simplify the number of constructors required for OptionTypeInfo and make the code a little clearer.

Add functions to the OptionTypeInfo for Prepare and Validate.  These methods allow types other than Configurable and Customizable to have Prepare and Validate logic.  These methods could be used by an option to guarantee that its settings were in a range or that a value was initialized.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9411

Reviewed By: pdillinger

Differential Revision: D36174849

Pulled By: mrambacher

fbshipit-source-id: 72517d8c6bab4723788a4c1a9e16590bff870125
2022-05-13 04:57:08 -07:00
sdong 736a7b5433 Remove own ToString() (#9955)
Summary:
ToString() is created as some platform doesn't support std::to_string(). However, we've already used std::to_string() by mistake for 16 months (in db/db_info_dumper.cc). This commit just remove ToString().

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9955

Test Plan: Watch CI tests

Reviewed By: riversand963

Differential Revision: D36176799

fbshipit-source-id: bdb6dcd0e3a3ab96a1ac810f5d0188f684064471
2022-05-06 13:03:58 -07:00
sdong 49628c9a83 Use std::numeric_limits<> (#9954)
Summary:
Right now we still don't fully use std::numeric_limits but use a macro, mainly for supporting VS 2013. Right now we only support VS 2017 and up so it is not a problem. The code comment claims that MinGW still needs it. We don't have a CI running MinGW so it's hard to validate. since we now require C++17, it's hard to imagine MinGW would still build RocksDB but doesn't support std::numeric_limits<>.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9954

Test Plan: See CI Runs.

Reviewed By: riversand963

Differential Revision: D36173954

fbshipit-source-id: a35a73af17cdcae20e258cdef57fcf29a50b49e0
2022-05-05 13:08:21 -07:00
Levi Tamasi db536ee045 Propagate errors from UpdateBoundaries (#9851)
Summary:
In `FileMetaData`, we keep track of the lowest-numbered blob file
referenced by the SST file in question for the purposes of BlobDB's
garbage collection in the `oldest_blob_file_number` field, which is
updated in `UpdateBoundaries`. However, with the current code,
`BlobIndex` decoding errors (or invalid blob file numbers) are swallowed
in this method. The patch changes this by propagating these errors
and failing the corresponding flush/compaction. (Note that since blob
references are generated by the BlobDB code and also parsed by
`CompactionIterator`, in reality this can only happen in the case of
memory corruption.)

This change necessitated updating some unit tests that involved
fake/corrupt `BlobIndex` objects. Some of these just used a dummy string like
`"blob_index"` as a placeholder; these were replaced with real `BlobIndex`es.
Some were relying on the earlier behavior to simulate corruption; these
were replaced with `SyncPoint`-based test code that corrupts a valid
blob reference at read time.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9851

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D35683671

Pulled By: ltamasi

fbshipit-source-id: f7387af9945c48e4d5c4cd864f1ba425c7ad51f6
2022-04-15 20:25:48 -07:00
Yanqin Jin 0bd4dcde6b CompactionIterator sees consistent view of which keys are committed (#9830)
Summary:
**This PR does not affect the functionality of `DB` and write-committed transactions.**

`CompactionIterator` uses `KeyCommitted(seq)` to determine if a key in the database is committed.
As the name 'write-committed' implies, if write-committed policy is used, a key exists in the database only if
it is committed. In fact, the implementation of `KeyCommitted()` is as follows:

```
inline bool KeyCommitted(SequenceNumber seq) {
  // For non-txn-db and write-committed, snapshot_checker_ is always nullptr.
  return snapshot_checker_ == nullptr ||
         snapshot_checker_->CheckInSnapshot(seq, kMaxSequence) == SnapshotCheckerResult::kInSnapshot;
}
```

With that being said, we focus on write-prepared/write-unprepared transactions.

A few notes:
- A key can exist in the db even if it's uncommitted. Therefore, we rely on `snapshot_checker_` to determine data visibility. We also require that all writes go through transaction API instead of the raw `WriteBatch` + `Write`, thus at most one uncommitted version of one user key can exist in the database.
- `CompactionIterator` outputs a key as long as the key is uncommitted.

Due to the above reasons, it is possible that `CompactionIterator` decides to output an uncommitted key without
doing further checks on the key (`NextFromInput()`). By the time the key is being prepared for output, the key becomes
committed because the `snapshot_checker_(seq, kMaxSequence)` becomes true in the implementation of `KeyCommitted()`.
Then `CompactionIterator` will try to zero its sequence number and hit assertion error if the key is a tombstone.

To fix this issue, we should make the `CompactionIterator` see a consistent view of the input keys. Note that
for write-prepared/write-unprepared, the background flush/compaction jobs already take a "job snapshot" before starting
processing keys. The job snapshot is released only after the entire flush/compaction finishes. We can use this snapshot
to determine whether a key is committed or not with minor change to `KeyCommitted()`.

```
inline bool KeyCommitted(SequenceNumber sequence) {
  // For non-txn-db and write-committed, snapshot_checker_ is always nullptr.
  return snapshot_checker_ == nullptr ||
         snapshot_checker_->CheckInSnapshot(sequence, job_snapshot_) ==
             SnapshotCheckerResult::kInSnapshot;
}
```

As a result, whether a key is committed or not will remain a constant throughout compaction, causing no trouble
for `CompactionIterator`s assertions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9830

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D35561162

Pulled By: riversand963

fbshipit-source-id: 0e00d200c195240341cfe6d34cbc86798b315b9f
2022-04-14 11:11:04 -07:00
Jay Zhuang dc1c90c4e3 Support canceling running RemoteCompaction on remote side (#9725)
Summary:
Add the ability to cancel remote compaction on the remote side by
setting `OpenAndCompactOptions.canceled` to true.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9725

Test Plan: added unittest

Reviewed By: ajkr

Differential Revision: D35018800

Pulled By: jay-zhuang

fbshipit-source-id: be3652f9645e0347df429e42a5614d5a9b3a1ec4
2022-04-13 13:28:09 -07:00
Jay Zhuang f934a0af46 Add event listener support on remote compactor side (#9821)
Summary:
So the user is able to set event listener on the compactor
side.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9821

Test Plan: unittest added

Reviewed By: ajkr

Differential Revision: D35485388

Pulled By: jay-zhuang

fbshipit-source-id: 669d8a3aaee012b75b940470306756c03ffa09b2
2022-04-12 17:25:36 -07:00
Yanqin Jin 0ad9ee30ce Remove dead code (#9825)
Summary:
Options `preserve_deletes` and `iter_start_seqnum` have been removed since 7.0.

This PR removes dead code related to these two removed options.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9825

Test Plan: make check

Reviewed By: akankshamahajan15

Differential Revision: D35517950

Pulled By: riversand963

fbshipit-source-id: 86282ce5ec4087acb94a06a42a1b6d55b1715482
2022-04-11 10:26:55 -07:00
sdong e03f8a0c12 L0 Subcompaction to trim input files (#9802)
Summary:
When sub compaction is decided for L0->L1 compaction, most of the cases, all L0 files will be involved in all sub compactions. However, it is not always the case. When files are generally (but not strictly) inserted in sequential order, there can be a subset of L0 files invovled. Yet RocksDB always open all those L0 files, and build an iterator, read many of the files' first of last block with expensive readahead. We trim some input files to reduce overhead a little bit.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9802

Test Plan: Add a unit test to cover this case and manually validate the behavior while running the test.

Reviewed By: ajkr

Differential Revision: D35371031

fbshipit-source-id: 701ed7375b5cbe41672e93b38fe8a1503dad08b6
2022-04-06 18:19:19 -07:00
KNOEEE cb4d188a34 Fix a bug in PosixClock (#9695)
Summary:
Multiplier here should be 1e6 to get microseconds.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9695

Reviewed By: ajkr

Differential Revision: D34897086

Pulled By: jay-zhuang

fbshipit-source-id: 9c1d0811ea740ba0a007edc2da199edbd000b88b
2022-03-21 16:11:02 -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
Jay Zhuang 2fbc672732 Add temperature information to the event listener callbacks (#9591)
Summary:
RocksDB try to provide temperature information in the event
listener callbacks. The information is not guaranteed, as some operation
like backup won't have these information.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9591

Test Plan: Added unittest

Reviewed By: siying, pdillinger

Differential Revision: D34309339

Pulled By: jay-zhuang

fbshipit-source-id: 4aca4f270f99fa49186d85d300da42594663d6d7
2022-02-18 11:23:18 -08:00
Jay Zhuang f092f0fa5d Add subcompaction event API (#9311)
Summary:
Add event callback for subcompaction and adds a sub_job_id to identify it.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9311

Reviewed By: ajkr

Differential Revision: D33892707

Pulled By: jay-zhuang

fbshipit-source-id: 57b5e5e594d61b2112d480c18a79a36751f65a4e
2022-02-17 15:47:10 -08:00
Andrew Kryczka babe56ddba Add rate limiter priority to ReadOptions (#9424)
Summary:
Users can set the priority for file reads associated with their operation by setting `ReadOptions::rate_limiter_priority` to something other than `Env::IO_TOTAL`. Rate limiting `VerifyChecksum()` and `VerifyFileChecksums()` is the motivation for this PR, so it also includes benchmarks and minor bug fixes to get that working.

`RandomAccessFileReader::Read()` already had support for rate limiting compaction reads. I changed that rate limiting to be non-specific to compaction, but rather performed according to the passed in `Env::IOPriority`. Now the compaction read rate limiting is supported by setting `rate_limiter_priority = Env::IO_LOW` on its `ReadOptions`.

There is no default value for the new `Env::IOPriority` parameter to `RandomAccessFileReader::Read()`. That means this PR goes through all callers (in some cases multiple layers up the call stack) to find a `ReadOptions` to provide the priority. There are TODOs for cases I believe it would be good to let user control the priority some day (e.g., file footer reads), and no TODO in cases I believe it doesn't matter (e.g., trace file reads).

The API doc only lists the missing cases where a file read associated with a provided `ReadOptions` cannot be rate limited. For cases like file ingestion checksum calculation, there is no API to provide `ReadOptions` or `Env::IOPriority`, so I didn't count that as missing.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9424

Test Plan:
- new unit tests
- new benchmarks on ~50MB database with 1MB/s read rate limit and 100ms refill interval; verified with strace reads are chunked (at 0.1MB per chunk) and spaced roughly 100ms apart.
  - setup command: `./db_bench -benchmarks=fillrandom,compact -db=/tmp/testdb -target_file_size_base=1048576 -disable_auto_compactions=true -file_checksum=true`
  - benchmarks command: `strace -ttfe pread64 ./db_bench -benchmarks=verifychecksum,verifyfilechecksums -use_existing_db=true -db=/tmp/testdb -rate_limiter_bytes_per_sec=1048576 -rate_limit_bg_reads=1 -rate_limit_user_ops=true -file_checksum=true`
- crash test using IO_USER priority on non-validation reads with https://github.com/facebook/rocksdb/issues/9567 reverted: `python3 tools/db_crashtest.py blackbox --max_key=1000000 --write_buffer_size=524288 --target_file_size_base=524288 --level_compaction_dynamic_level_bytes=true --duration=3600 --rate_limit_bg_reads=true --rate_limit_user_ops=true --rate_limiter_bytes_per_sec=10485760 --interval=10`

Reviewed By: hx235

Differential Revision: D33747386

Pulled By: ajkr

fbshipit-source-id: a2d985e97912fba8c54763798e04f006ccc56e0c
2022-02-16 23:18:14 -08:00
Peter Dillinger e24734f843 Use -Wno-invalid-offsetof instead of dangerous offset_of hack (#9563)
Summary:
After https://github.com/facebook/rocksdb/issues/9515 added a unique_ptr to Status, we see some
warnings-as-error in some internal builds like this:

```
stderr: rocksdb/src/db/compaction/compaction_job.cc:2839:7: error:
offset of on non-standard-layout type 'struct CompactionServiceResult'
[-Werror,-Winvalid-offsetof]
     {offsetof(struct CompactionServiceResult, status),
      ^                                        ~~~~~~
```

I see three potential solutions to resolving this:

* Expand our use of an idiom that works around the warning (see offset_of
functions removed in this change, inspired by
https://gist.github.com/graphitemaster/494f21190bb2c63c5516)  However,
this construction is invoking undefined behavior that assumes consistent
layout with no compiler-introduced indirection. A compiler incompatible
with our assumptions will likely compile the code and exhibit undefined
behavior.
* Migrate to something in place of offset, like a function mapping
CompactionServiceResult* to Status* (for the `status` field). This might
be required in the long term.
* **Selected:** Use our new C++17 dependency to use offsetof in a well-defined way
when the compiler allows it. From a comment on
https://gist.github.com/graphitemaster/494f21190bb2c63c5516:

> A final note: in C++17, offsetof is conditionally supported, which
> means that you can use it on any type (not just standard layout
> types) and the compiler will error if it can't compile it correctly.
> That appears to be the best option if you can live with C++17 and
> don't need constexpr support.

The C++17 semantics are confirmed on
https://en.cppreference.com/w/cpp/types/offsetof, so we can suppress the
warning as long as we accept that we might run into a compiler that
rejects the code, and at that point we will find a solution, such as
the more intrusive "migrate" solution above.

Although this is currently only showing in our buck build, it will
surely show up also with make and cmake, so I have updated those
configurations as well.

Also in the buck build, -Wno-expansion-to-defined does not appear to be
needed anymore (both current compiler configurations) so I
removed it.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9563

Test Plan: Tried out buck builds with both current compiler configurations

Reviewed By: riversand963

Differential Revision: D34220931

Pulled By: pdillinger

fbshipit-source-id: d39436008259bd1eaaa87c77be69fb2a5b559e1f
2022-02-15 09:19:19 -08:00
Levi Tamasi 320d9a8e8a Use a sorted vector instead of a map to store blob file metadata (#9526)
Summary:
The patch replaces `std::map` with a sorted `std::vector` for
`VersionStorageInfo::blob_files_` and preallocates the space
for the `vector` before saving the `BlobFileMetaData` into the
new `VersionStorageInfo` in `VersionBuilder::Rep::SaveBlobFilesTo`.
These changes reduce the time the DB mutex is held while
saving new `Version`s, and using a sorted `vector` also makes
lookups faster thanks to better memory locality.

In addition, the patch introduces helper methods
`VersionStorageInfo::GetBlobFileMetaData` and
`VersionStorageInfo::GetBlobFileMetaDataLB` that can be used by
clients to perform lookups in the `vector`, and does some general
cleanup in the parts of code where blob file metadata are used.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9526

Test Plan:
Ran `make check` and the crash test script for a while.

Performance was tested using a load-optimized benchmark (`fillseq` with vector memtable, no WAL) and small file sizes so that a significant number of files are produced:

```
numactl --interleave=all ./db_bench --benchmarks=fillseq --allow_concurrent_memtable_write=false --level0_file_num_compaction_trigger=4 --level0_slowdown_writes_trigger=20 --level0_stop_writes_trigger=30 --max_background_jobs=8 --max_write_buffer_number=8 --db=/data/ltamasi-dbbench --wal_dir=/data/ltamasi-dbbench --num=800000000 --num_levels=8 --key_size=20 --value_size=400 --block_size=8192 --cache_size=51539607552 --cache_numshardbits=6 --compression_max_dict_bytes=0 --compression_ratio=0.5 --compression_type=lz4 --bytes_per_sync=8388608 --cache_index_and_filter_blocks=1 --cache_high_pri_pool_ratio=0.5 --benchmark_write_rate_limit=0 --write_buffer_size=16777216 --target_file_size_base=16777216 --max_bytes_for_level_base=67108864 --verify_checksum=1 --delete_obsolete_files_period_micros=62914560 --max_bytes_for_level_multiplier=8 --statistics=0 --stats_per_interval=1 --stats_interval_seconds=20 --histogram=1 --memtablerep=skip_list --bloom_bits=10 --open_files=-1 --subcompactions=1 --compaction_style=0 --min_level_to_compress=3 --level_compaction_dynamic_level_bytes=true --pin_l0_filter_and_index_blocks_in_cache=1 --soft_pending_compaction_bytes_limit=167503724544 --hard_pending_compaction_bytes_limit=335007449088 --min_level_to_compress=0 --use_existing_db=0 --sync=0 --threads=1 --memtablerep=vector --allow_concurrent_memtable_write=false --disable_wal=1 --enable_blob_files=1 --blob_file_size=16777216 --min_blob_size=0 --blob_compression_type=lz4 --enable_blob_garbage_collection=1 --seed=<some value>
```

Final statistics before the patch:

```
Cumulative writes: 0 writes, 700M keys, 0 commit groups, 0.0 writes per commit group, ingest: 284.62 GB, 121.27 MB/s
Interval writes: 0 writes, 334K keys, 0 commit groups, 0.0 writes per commit group, ingest: 139.28 MB, 72.46 MB/s
```

With the patch:

```
Cumulative writes: 0 writes, 760M keys, 0 commit groups, 0.0 writes per commit group, ingest: 308.66 GB, 131.52 MB/s
Interval writes: 0 writes, 445K keys, 0 commit groups, 0.0 writes per commit group, ingest: 185.35 MB, 93.15 MB/s
```

Total time to complete the benchmark is 2611 seconds with the patch, down from 2986 secs.

Reviewed By: riversand963

Differential Revision: D34082728

Pulled By: ltamasi

fbshipit-source-id: fc598abf676dce436734d06bb9d2d99a26a004fc
2022-02-09 12:36:43 -08:00
Peter Dillinger a495448eea Revisit #9118 for compaction outputs (#9480)
Summary:
Crash test recently started showing failures as in https://github.com/facebook/rocksdb/issues/9118 but
for files created by compaction. This change applies a similar fix.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9480

Test Plan:
Updated / extended unit test. (Some re-arranging to do the
simpler compaction testing before this special case.)

Reviewed By: ltamasi

Differential Revision: D33909835

Pulled By: pdillinger

fbshipit-source-id: 58e4b44e4ecc2d21e4df2c2d8440ec0633aa1f6c
2022-02-01 11:08:34 -08:00
Peter Dillinger fc9d4071f0 Fast path for detecting unchanged prefix_extractor (#9407)
Summary:
Fixes a major performance regression in 6.26, where
extra CPU is spent in SliceTransform::AsString when reads involve
a prefix_extractor (Get, MultiGet, Seek). Common case performance
is now better than 6.25.

This change creates a "fast path" for verifying that the current prefix
extractor is unchanged and compatible with what was used to
generate a table file. This fast path detects the common case by
pointer comparison on the current prefix_extractor and a "known
good" prefix extractor (if applicable) that is saved at the time the
table reader is opened. The "known good" prefix extractor is saved
as another shared_ptr copy (in an existing field, however) to ensure
the pointer is not recycled.

When the prefix_extractor has changed to a different instance but
same compatible configuration (rare, odd), performance is still a
regression compared to 6.25, but this is likely acceptable because
of the oddity of such a case. The performance of incompatible
prefix_extractor is essentially unchanged.

Also fixed a minor case (ForwardIterator) where a prefix_extractor
could be used via a raw pointer after being freed as a shared_ptr,
if replaced via SetOptions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9407

Test Plan:
## Performance
Populate DB with `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks=fillrandom -num=10000000 -disable_wal=1 -write_buffer_size=10000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -prefix_size=12`

Running head-to-head comparisons simultaneously with `TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -use_existing_db -readonly -benchmarks=seekrandom -num=10000000 -duration=20 -disable_wal=1 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -prefix_size=12`

Below each is compared by ops/sec vs. baseline which is version 6.25 (multiple baseline runs because of variable machine load)

v6.26: 4833 vs. 6698 (<- major regression!)
v6.27: 4737 vs. 6397 (still)
New: 6704 vs. 6461 (better than baseline in common case)
Disabled fastpath: 4843 vs. 6389 (e.g. if prefix extractor instance changes but is still compatible)
Changed prefix size (no usable filter) in new: 787 vs. 5927
Changed prefix size (no usable filter) in new & baseline: 773 vs. 784

Reviewed By: mrambacher

Differential Revision: D33677812

Pulled By: pdillinger

fbshipit-source-id: 571d9711c461fb97f957378a061b7e7dbc4d6a76
2022-01-21 11:37:46 -08:00
Jay Zhuang 29102641dd Skip directory fsync for filesystem btrfs (#8903)
Summary:
Directory fsync might be expensive on btrfs and it may not be needed.
Here are 4 directory fsync cases:
1. creating a new file: dir-fsync is not needed on btrfs, as long as the
   new file itself is synced.
2. renaming a file: dir-fsync is not needed if the renamed file is
   synced. So an API `FsyncAfterFileRename(filename, ...)` is provided
   to sync the file on btrfs. By default, it just calls dir-fsync.
3. deleting files: dir-fsync is forced by set
   `IOOptions.force_dir_fsync = true`
4. renaming multiple files (like backup and checkpoint): dir-fsync is
   forced, the same as above.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8903

Test Plan: run tests on btrfs and non btrfs

Reviewed By: ajkr

Differential Revision: D30885059

Pulled By: jay-zhuang

fbshipit-source-id: dd2730b31580b0bcaedffc318a762d7dbf25de4a
2021-11-03 12:21:27 -07:00
sdong a2b9be42b6 Try to start TTL earlier with kMinOverlappingRatio is used (#8749)
Summary:
Right now, when options.ttl is set, compactions are triggered around the time when TTL is reached. This might cause extra compactions which are often bursty. This commit tries to mitigate it by picking those files earlier in normal compaction picking process. This is only implemented using kMinOverlappingRatio with Leveled compaction as it is the default value and it is more complicated to change other styles.

When a file is aged more than ttl/2, RocksDB starts to boost the compaction priority of files in normal compaction picking process, and hope by the time TTL is reached, very few extra compaction is needed.

In order for this to work, another change is made: during a compaction, if an output level file is older than ttl/2, cut output files based on original boundary (if it is not in the last level). This is to make sure that after an old file is moved to the next level, and new data is merged from the upper level, the new data falling into this range isn't reset with old timestamp. Without this change, in many cases, most files from one level will keep having old timestamp, even if they have newer data and we stuck in it.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8749

Test Plan: Add a unit test to test the boosting logic. Will add a unit test to test it end-to-end.

Reviewed By: jay-zhuang

Differential Revision: D30735261

fbshipit-source-id: 503c2d89250b22911eb99e72b379be154de3428e
2021-11-01 14:36:31 -07:00
sdong c66b4429ff Incremental Space Amp Compactions in Universal Style (#8655)
Summary:
This commit introduces incremental compaction in univeral style for space amplification. This follows the first improvement mentioned in https://rocksdb.org/blog/2021/04/12/universal-improvements.html . The implemention simply picks up files about size of max_compaction_bytes to compact and execute if the penalty is not too big. More optimizations can be done in the future, e.g. prioritizing between this compaction and other types. But for now, the feature is supposed to be functional and can often reduce frequency of full compactions, although it can introduce penalty.

In order to add cut files more efficiently so that more files from upper levels can be included, SST file cutting threshold (for current file + overlapping parent level files) is set to 1.5X of target file size. A 2MB target file size will generate files like this: https://gist.github.com/siying/29d2676fba417404f3c95e6c013c7de8 Number of files indeed increases but it is not out of control.

Two set of write benchmarks are run:
1. For ingestion rate limited scenario, we can see full compaction is mostly eliminated: https://gist.github.com/siying/959bc1186066906831cf4c808d6e0a19 . The write amp increased from 7.7 to 9.4, as expected. After applying file cutting, the number is improved to 8.9. In another benchmark, the write amp is even better with the incremental approach: https://gist.github.com/siying/d1c16c286d7c59c4d7bba718ca198163
2. For ingestion rate unlimited scenario, incremental compaction turns out to be too expensive most of the time and is not executed, as expected.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8655

Test Plan: Add unit tests to the functionality.

Reviewed By: ajkr

Differential Revision: D31787034

fbshipit-source-id: ce813e63b15a61d5a56e97bf8902a1b28e011beb
2021-10-20 10:04:13 -07:00
Levi Tamasi 3e1bf771a3 Make it possible to force the garbage collection of the oldest blob files (#8994)
Summary:
The current BlobDB garbage collection logic works by relocating the valid
blobs from the oldest blob files as they are encountered during compaction,
and cleaning up blob files once they contain nothing but garbage. However,
with sufficiently skewed workloads, it is theoretically possible to end up in a
situation when few or no compactions get scheduled for the SST files that contain
references to the oldest blob files, which can lead to increased space amp due
to the lack of GC.

In order to efficiently handle such workloads, the patch adds a new BlobDB
configuration option called `blob_garbage_collection_force_threshold`,
which signals to BlobDB to schedule targeted compactions for the SST files
that keep alive the oldest batch of blob files if the overall ratio of garbage in
the given blob files meets the threshold *and* all the given blob files are
eligible for GC based on `blob_garbage_collection_age_cutoff`. (For example,
if the new option is set to 0.9, targeted compactions will get scheduled if the
sum of garbage bytes meets or exceeds 90% of the sum of total bytes in the
oldest blob files, assuming all affected blob files are below the age-based cutoff.)
The net result of these targeted compactions is that the valid blobs in the oldest
blob files are relocated and the oldest blob files themselves cleaned up (since
*all* SST files that rely on them get compacted away).

These targeted compactions are similar to periodic compactions in the sense
that they force certain SST files that otherwise would not get picked up to undergo
compaction and also in the sense that instead of merging files from multiple levels,
they target a single file. (Note: such compactions might still include neighboring files
from the same level due to the need of having a "clean cut" boundary but they never
include any files from any other level.)

This functionality is currently only supported with the leveled compaction style
and is inactive by default (since the default value is set to 1.0, i.e. 100%).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8994

Test Plan: Ran `make check` and tested using `db_bench` and the stress/crash tests.

Reviewed By: riversand963

Differential Revision: D31489850

Pulled By: ltamasi

fbshipit-source-id: 44057d511726a0e2a03c5d9313d7511b3f0c4eab
2021-10-11 18:03:01 -07:00
Jay Zhuang 6b34eb0ebc Add remote compaction read/write bytes statistics (#8939)
Summary:
Add basic read/write bytes statistics on the primary side:
`REMOTE_COMPACT_READ_BYTES`
`REMOTE_COMPACT_WRITE_BYTES`

Fixed existing statistics missing some IO for remote compaction.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8939

Test Plan: CI

Reviewed By: ajkr

Differential Revision: D31074672

Pulled By: jay-zhuang

fbshipit-source-id: c57afdba369990185008ffaec7e3fe7c62e8902f
2021-09-28 14:00:37 -07:00
Jay Zhuang 1c290c785d RemoteCompaction support Fallback to local compaction (#8709)
Summary:
Add support for fallback to local compaction, the user can
return `CompactionServiceJobStatus::kUseLocal` to instruct RocksDB to
run the compaction locally instead of waiting for the remote compaction
result.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8709

Test Plan: unittest

Reviewed By: ajkr

Differential Revision: D30560163

Pulled By: jay-zhuang

fbshipit-source-id: 65d8905a4a1bc185a68daa120997f21d3198dbe1
2021-09-18 00:25:04 -07:00
Akanksha Mahajan d6aa8c49f8 Expose blob file information through the EventListener interface (#8675)
Summary:
1. Extend FlushJobInfo and CompactionJobInfo with information about the blob files generated by flush/compaction jobs. This PR add two structures BlobFileInfo and BlobFileGarbageInfo that contains the required information of blob files.
 2. Notify the creation and deletion of blob files through OnBlobFileCreationStarted, OnBlobFileCreated, and OnBlobFileDeleted.
 3. Test OnFile*Finish operations notifications with Blob Files.
 4. Log the blob file creation/deletion events through EventLogger in Log file.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8675

Test Plan: Add new unit tests in listener_test

Reviewed By: ltamasi

Differential Revision: D30412613

Pulled By: akankshamahajan15

fbshipit-source-id: ca51b63c6e8c8d0485a38c503572bc5a82bd5d07
2021-09-16 17:23:36 -07:00
Jay Zhuang b97c53b629 Add compaction priority information in RemoteCompaction (#8707)
Summary:
Add compaction priority information in RemoteCompaction, which
can be used to schedule high priority job first.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8707

Test Plan: unittest

Reviewed By: ajkr

Differential Revision: D30548401

Pulled By: jay-zhuang

fbshipit-source-id: b30446511fb31b4583c49edd8565d496cf013a34
2021-09-16 15:09:35 -07:00
Jay Zhuang 249b1078c9 Add extra information to RemoteCompaction APIs (#8680)
Summary:
Currently, we only provide job_id in RemoteCompaction APIs, the
main problem of `job_id` is it cannot uniquely identify a compaction job
between DB instances or between sessions.
Providing DB and session id to the user, which will make building cross
DB compaction service easier.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8680

Test Plan: unittest

Reviewed By: ajkr

Differential Revision: D30444859

Pulled By: jay-zhuang

fbshipit-source-id: fdf107f4286564049637f154193c6d94c3c59448
2021-08-23 16:27:38 -07:00
Levi Tamasi 6878cedcc3 Add statistics support to integrated BlobDB (#8667)
Summary:
The patch adds statistics support to the integrated BlobDB implementation,
namely the tickers `BLOB_DB_BLOB_FILE_BYTES_READ` and
`BLOB_DB_GC_{NUM_KEYS,BYTES}_RELOCATED`, and the histograms
`BLOB_DB_(DE)COMPRESSION_MICROS`. (Some other statistics, like
`BLOB_DB_BLOB_FILE_BYTES_WRITTEN`, `BLOB_DB_BLOB_FILE_SYNCED`,
`BLOB_DB_BLOB_FILE_{READ,WRITE,SYNC}_MICROS` were already supported.)
Note that the vast majority of the old BlobDB's tickers/histograms are not
really applicable to the new implementation, since they e.g. pertain to calling
dedicated BlobDB APIs (which the integrated BlobDB does not have) or are
tied to the legacy BlobDB's design of writing blob files synchronously when
a write API is called. Such statistics are marked "legacy BlobDB only" in
`statistics.h`.

Fixes https://github.com/facebook/rocksdb/issues/8645 .

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8667

Test Plan: Ran `make check` and tested the new statistics using `db_bench`.

Reviewed By: riversand963

Differential Revision: D30356884

Pulled By: ltamasi

fbshipit-source-id: 5f8a833faee60401c5643c2f0a6c0415488190a4
2021-08-17 17:22:31 -07:00
sdong e7c24168d8 Move old files to warm tier in FIFO compactions (#8310)
Summary:
Some FIFO users want to keep the data for longer, but the old data is rarely accessed. This feature allows users to configure FIFO compaction so that data older than a threshold is moved to a warm storage tier.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8310

Test Plan: Add several unit tests.

Reviewed By: ajkr

Differential Revision: D28493792

fbshipit-source-id: c14824ea634814dee5278b449ab5c98b6e0b5501
2021-08-09 12:51:14 -07:00
leipeng 4171e3db9b CompactionJob::Install(): fix log truncation (#8563)
Summary:
event log info may be truncated, the default buffer size is 512, this PR changes buffer size to 8192.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8563

Reviewed By: ajkr

Differential Revision: D29838229

Pulled By: jay-zhuang

fbshipit-source-id: 00c5dea3caff0641a209f02c972e92d65b505f50
2021-07-23 11:39:24 -07:00
Jay Zhuang 3503f28982 Add sub-compaction support for RemoteCompaction (#8364)
Summary:
Change the job_id for remote compaction interface, which will include
both internal compaction job_id, also a sub_compaction_job_id. It is not
a backward compatible change. The user needs to update interface during
upgrade. (We will avoid backward incompatible change after the feature is
not experimental.)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8364

Reviewed By: ajkr

Differential Revision: D28917301

Pulled By: jay-zhuang

fbshipit-source-id: 6d72a21f652bb517ad6954d0387b496797fc4e11
2021-06-29 10:42:19 -07:00