Summary:
Enabling time PerfCounter stats in RocksDB is currently very expensive, as it enables all sorts of relatively uninteresting stats, such as iteration, point lookup breakdown etc. This PR adds a new perf level between `kEnableCount` and `kEnableTimeExceptForMutex` to enable stats for time spent by user (i.e a RocksDB user) threads blocked by other RocksDB threads or events, such as a write group leader, write delay or stalls etc. It does not include time spent waiting to acquire mutexes, or waiting for IO.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12368
Test Plan: Add a unit test for write_thread_wait_nanos
Reviewed By: ajkr
Differential Revision: D54021583
Pulled By: anand1976
fbshipit-source-id: 3f6fcf71010132ffffca0391a5565f3b59fddd48
Summary:
This PR expands on the capabilities added in https://github.com/facebook/rocksdb/issues/12343. It adds sanity checks for external file's comparator name and user-defined timestamps related flag. With this, it now supports ingesting files to a column family that enables user-defined timestamps in Memtable only feature.
Two fields in the table properties are used for aformentioned check: 1) the comparator name, it records what comparator is used to create this external sst file, 2) the flag `user_defined_timestamps_persisted`. We compare these two fields with the column family's settings. The details are in util function `ValidateUserDefinedTimestampsOptions`.
To optimize for the majority of the cases where sanity check should pass and the table properties read should not affect how `TableReader` is constructed, instead of read the table properties block separately and use it for sanity check before creating a `TableReader`. We continue using the current flow to first create a `TableReader`, use it for reading table properties and do sanity checks, and reset the`TableReader` for the case where the column family enables UDTs in memtable only feature, and the external file does not contain user-defined timestamps.
This PR also groups other table properties related sanity check in function `GetIngestedFileInfo` into the newly added `SanityCheckTableProperties` function.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12356
Test Plan:
added unit test
existing unit test
Reviewed By: cbi42
Differential Revision: D54025116
Pulled By: jowlyzhang
fbshipit-source-id: a918276c15f9908bd9df8513ce667638882e1554
Summary:
This occasional filesystem read in the write path has caused user pain. It doesn't seem very useful considering it only limits one component's merge chain length, and only helps merge uncached (i.e., infrequently read) values. This PR proposes allowing `max_successive_merges` to be exceeded when the value cannot be read from in-memory components. I included a rollback flag (`strict_max_successive_merges`) just in case.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12365
Test Plan:
"rocksdb.block.cache.data.add" is number of data blocks read from filesystem. Since the benchmark is write-only, compaction is disabled, and flush doesn't read data blocks, any nonzero value means the user write issued the read.
```
$ for s in false true; do echo -n "strict_max_successive_merges=$s: " && ./db_bench -value_size=64 -write_buffer_size=131072 -writes=128 -num=1 -benchmarks=mergerandom,flush,mergerandom -merge_operator=stringappend -disable_auto_compactions=true -compression_type=none -strict_max_successive_merges=$s -max_successive_merges=100 -statistics=true |& grep 'block.cache.data.add COUNT' ; done
strict_max_successive_merges=false: rocksdb.block.cache.data.add COUNT : 0
strict_max_successive_merges=true: rocksdb.block.cache.data.add COUNT : 1
```
Reviewed By: hx235
Differential Revision: D53982520
Pulled By: ajkr
fbshipit-source-id: e40f761a60bd601f232417ac0058e4a33ee9c0f4
Summary:
A lot of variants of Get and MultiGet have been added to `include/rocksdb/db.h` over the years. Try to consolidate them by marking variants that don't return timestamps as deprecated. The underlying DB implementation will check and return Status::NotSupported() if it doesn't support returning timestamps and the caller asks for it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12327
Reviewed By: pdillinger
Differential Revision: D53828151
Pulled By: anand1976
fbshipit-source-id: e0b5ca42d32daa2739d5f439a729815a2d4ff050
Summary:
Modify ReadAsync callback API to remove const from FSReadRequest as const doesn't let to fs_scratch to move the ownership.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11649
Test Plan: CircleCI jobs
Reviewed By: anand1976
Differential Revision: D53585309
Pulled By: akankshamahajan15
fbshipit-source-id: 3bff9035db0e6fbbe34721a5963443355807420d
Summary:
The RocksDB ticker and histogram statistics were out of sync between the C++ and Java code, with a number of newer stats missing in TickerType.java and HistogramType.java. Also, there were gaps in numbering in portal.h, which could soon become an issue due to the number of tickers and the fact that we're limited to 1 byte in Java. This PR adds the missing stats, and re-numbers all of them. It also moves some stats around to try to group related stats together. Since this will go into a major release, compatibility shouldn't be an issue.
This should be automated at some point, since the current process is somewhat error prone.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12355
Reviewed By: jaykorean
Differential Revision: D53825324
Pulled By: anand1976
fbshipit-source-id: 298c180872f4b9f1ee54b8bb22f4e280458e7e09
Summary:
This change contains a prototype new API for "higher dimensional" filtering of read queries. Existing filters treat keys as one-dimensional, either as distinct points (whole key) or as contiguous ranges in comparator order (prefix filters). The proposed KeySegmentsExtractor allows treating keys as multi-dimensional for filtering purposes even though they still have a single total order across dimensions. For example, consider these keys in different LSM levels:
L0:
abc_0123
abc_0150
def_0114
ghi_0134
L1:
abc_0045
bcd_0091
def_0077
xyz_0080
If we get a range query for [def_0100, def_0200), a prefix filter (up to the underscore) will tell us that both levels are potentially relevant. However, if each SST file stores a simple range of the values for the second segment of the key, we would see that L1 only has [0045, 0091] which (under certain required assumptions) we are sure does not overlap with the given range query. Thus, we can filter out processing or reading any index or data blocks from L1 for the query.
This kind of case shows up with time-ordered data but is more general than filtering based on user timestamp. See https://github.com/facebook/rocksdb/issues/11332 . Here the "time" segments of the keys are meaningfully ordered with respect to each other even when the previous segment is different, so summarizing data along an alternate dimension of the key like this can work well for filtering.
This prototype implementation simply leverages existing APIs for user table properties and table filtering, which is not very CPU efficient. Eventually, we expect to create a native implementation. However, I have put some significant
thought and engineering into the new APIs overall, which I expect to be close to refined enough for production.
For details, see new public APIs in experimental.h. For a detailed example, see the new unit test in db_bloom_filter_test.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12075
Test Plan: Unit test included
Reviewed By: jowlyzhang
Differential Revision: D53619406
Pulled By: pdillinger
fbshipit-source-id: 9e6e7b82b4db8d815db76a6ab340e90db2c191f2
Summary:
There is no strong reason for user to need this mode while on the other hand, its behavior is destructive.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12337
Reviewed By: hx235
Differential Revision: D53630393
Pulled By: jowlyzhang
fbshipit-source-id: ce94b537258102cd98f89aa4090025663664dd78
Summary:
This PR adds initial support to bulk loading external sst files with user-defined timestamps.
To ensure this invariant is met while ingesting external files:
assume there are two internal keys: <K, ts1, seq1> and <K, ts2, seq2>, the following should hold:
ts1 < ts2 iff. seq1 < seq2
These extra requirements are added for ingesting external files with user-defined timestamps:
1) A file with overlapping user key (without timestamp) range with the db cannot be ingested. This is because we cannot ensure above invariant is met without checking each overlapped key's timestamp and compare it with the timestamp from the db. This is an expensive step. This bulk loading feature will be used by MyRocks and currently their usage can guarantee ingested file's key range doesn't overlap with db.
4f3a57a13f/storage/rocksdb/ha_rocksdb.cc (L3312)
We can consider loose this requirement by doing this check in the future, this initial support just disallow this.
2) Files with overlapping user key (without timestamp) range are not allowed to be ingested. For similar reasons, it's hard to ensure above invariant is met. For example, if we have two files where user keys are interleaved like this:
file1: [c10, c8, f10, f5]
file2: [b5, c11, f4]
Either file1 gets a bigger global seqno than file2, or the other way around, above invariant cannot be met.
So we disallow this.
2) When a column family enables user-defined timestamps, it doesn't support ingestion behind mode. Ingestion behind currently simply puts the file at the bottommost level, and assign a global seqno 0 to the file. We need to do similar search though the LSM tree for key range overlap checks to make sure aformentioned invariant is met. So this initial support disallow this mode. We can consider adding it in the future.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12343
Test Plan: Add unit tests
Reviewed By: cbi42
Differential Revision: D53686182
Pulled By: jowlyzhang
fbshipit-source-id: f05e3fb27967f7974ed40179d78634c40ecfb136
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12347
`DBImpl::disable_delete_obsolete_files_` should only be accessed while holding the DB mutex to prevent data races. There's a piece of logic in `DBImpl::RenameTempFileToOptionsFile` where this synchronization was previously missing. The patch fixes this issue similarly to how it's handled in `DisableFileDeletions` and `EnableFileDeletions`, that is, by saving the counter value while holding the mutex and then performing the actual file deletion outside the critical section. Note: this PR only fixes the race itself; as a followup, we can also look into cleaning up and optimizing the file deletion logic (which is currently inefficient on multiple different levels).
Reviewed By: jowlyzhang
Differential Revision: D53675153
fbshipit-source-id: 5358e894ee6829d3edfadac50a93d97f8819e481
Summary:
The following are risks associated with pointer-to-pointer reinterpret_cast:
* Can produce the "wrong result" (crash or memory corruption). IIRC, in theory this can happen for any up-cast or down-cast for a non-standard-layout type, though in practice would only happen for multiple inheritance cases (where the base class pointer might be "inside" the derived object). We don't use multiple inheritance a lot, but we do.
* Can mask useful compiler errors upon code change, including converting between unrelated pointer types that you are expecting to be related, and converting between pointer and scalar types unintentionally.
I can only think of some obscure cases where static_cast could be troublesome when it compiles as a replacement:
* Going through `void*` could plausibly cause unnecessary or broken pointer arithmetic. Suppose we have
`struct Derived: public Base1, public Base2`. If we have `Derived*` -> `void*` -> `Base2*` -> `Derived*` through reinterpret casts, this could plausibly work (though technical UB) assuming the `Base2*` is not dereferenced. Changing to static cast could introduce breaking pointer arithmetic.
* Unnecessary (but safe) pointer arithmetic could arise in a case like `Derived*` -> `Base2*` -> `Derived*` where before the Base2 pointer might not have been dereferenced. This could potentially affect performance.
With some light scripting, I tried replacing pointer-to-pointer reinterpret_casts with static_cast and kept the cases that still compile. Most occurrences of reinterpret_cast have successfully been changed (except for java/ and third-party/). 294 changed, 257 remain.
A couple of related interventions included here:
* Previously Cache::Handle was not actually derived from in the implementations and just used as a `void*` stand-in with reinterpret_cast. Now there is a relationship to allow static_cast. In theory, this could introduce pointer arithmetic (as described above) but is unlikely without multiple inheritance AND non-empty Cache::Handle.
* Remove some unnecessary casts to void* as this is allowed to be implicit (for better or worse).
Most of the remaining reinterpret_casts are for converting to/from raw bytes of objects. We could consider better idioms for these patterns in follow-up work.
I wish there were a way to implement a template variant of static_cast that would only compile if no pointer arithmetic is generated, but best I can tell, this is not possible. AFAIK the best you could do is a dynamic check that the void* conversion after the static cast is unchanged.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12308
Test Plan: existing tests, CI
Reviewed By: ltamasi
Differential Revision: D53204947
Pulled By: pdillinger
fbshipit-source-id: 9de23e618263b0d5b9820f4e15966876888a16e2
Summary:
Introduce some different range classes `UserKeyRange` and `UserKeyRangePtr` to be used by internal implementation. The `Range` class is used in both public APIs like `DB::GetApproximateSizes`, `DB::GetApproximateMemTableStats`, `DB::GetPropertiesOfTablesInRange` etc and internal implementations like `ColumnFamilyData::RangesOverlapWithMemtables`, `VersionSet::GetPropertiesOfTablesInRange`.
These APIs have different expectations of what keys this range class contain. Public API users are supposed to populate the range with the user keys without timestamp, in the same way that point lookup and range scan APIs' key input only expect the user key without timestamp. The internal APIs implementation expect a user key whose format is compatible with the user comparator, a.k.a a user key with the timestamp.
This PR contains:
1) introducing counterpart range class `UserKeyRange` `UserKeyRangePtr` for internal implementation while leave the existing `Range` and `RangePtr` class only for public APIs. Internal implementations are updated to use this new class instead.
2) add user-defined timestamp support for `DB::GetPropertiesOfTablesInRange` API and `DeleteFilesInRanges` API.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12071
Test Plan:
existing tests
Added test for `DB::GetPropertiesOfTablesInRange` and `DeleteFilesInRanges` APIs for when user-defined timestamp is enabled.
The change in external_file_ingestion_job doesn't have a user-defined timestamp enabled test case coverage, will add one in a follow up PR that adds file ingestion support for UDT.
Reviewed By: ltamasi
Differential Revision: D53292608
Pulled By: jowlyzhang
fbshipit-source-id: 9a9279e23c640a6d8f8232636501a95aef7638b8
Summary:
info_log gets an error logged when wal_dir or a db_path/cf_path is missing. Under this condition, the directory is created later (in DBImpl::Recover -> Directories::SetDirectories) with no error status returned.
To avoid error spam in logs, change these to a descriptive "header" log entry.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12326
Test Plan: manual with DBBasicTest.DBCloseAllDirectoryFDs which exercises this code
Reviewed By: jowlyzhang
Differential Revision: D53374743
Pulled By: pdillinger
fbshipit-source-id: 32d1ce18809da13a25bdd6183d661f66a3b6a111
Summary:
The option is introduced in https://github.com/facebook/rocksdb/issues/10835 to allow disabling the new compaction behavior if it's not safe. The option is enabled by default and there has not been a need to disable it. So it should be safe to remove now.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12323
Reviewed By: ajkr
Differential Revision: D53330336
Pulled By: cbi42
fbshipit-source-id: 36eef4664ac96b3a7ed627c48bd6610b0a7eafc5
Summary:
The option is introduced in https://github.com/facebook/rocksdb/issues/10655 to allow reverting to old behavior. The option is enabled by default and there has not been a need to disable it. Remove it for 9.0 release. Also fixed and improved a few unit tests that depended on setting this option to false.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12325
Test Plan: existing tests.
Reviewed By: hx235
Differential Revision: D53369430
Pulled By: cbi42
fbshipit-source-id: 0ec2440ca8d88db7f7211c581542c7581bd4d3de
Summary:
I've always found this name difficult to read, because it sounds like it's for collecting int(eger)
table properties.
I'm fixing this now to set up for a change that I have stubbed out in the public API (table_properties.h):
a new adapter function `TablePropertiesCollector::AsInternal()` that allows RocksDB-provided
TablePropertiesCollectors (such as CompactOnDeletionCollector) to implement the easier-to-upgrade
internal interface while still (superficially) implementing the public interface. In addition to added flexibility,
this should be a performance improvement as the adapter class UserKeyTablePropertiesCollector can be
avoided for such cases where a RocksDB-provided collector is used (AsInternal() returns non-nullptr).
table_properties.h is the only file with changes that aren't simple find-replace renaming.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12320
Test Plan: existing tests, CI
Reviewed By: ajkr
Differential Revision: D53336945
Pulled By: pdillinger
fbshipit-source-id: 02535bcb30bbfb00e29e8478af62e5dad50a63b8
Summary:
The RocksDB correctness testing has recently discovered a possible, but very unlikely, correctness issue with MultiGet. The issue happens when all of the below conditions are met -
1. Duplicate keys in a MultiGet batch
2. Key matches the last key in a non-zero, non-bottommost level file
3. Final value is not in the file (merge operand, not snapshot visible etc)
4. Multiple entries exist for the key in the file spanning more than 1 data block. This can happen due to snapshots, which would force multiple versions of the key in the file, and they may spill over to another data block
5. Lookup attempt in the SST for the first of the duplicates fails with IO error on a data block (NOT the first data block, but the second or subsequent uncached block), but no errors for the other duplicates
6. Value or merge operand for the key is present in the very next level
The problem is, in FilePickerMultiGet, when looking up keys in a level we use FileIndexer and the overlapping file in the current level to determine the search bounds for that key in the file list in the next level. If the next level is empty, the search bounds are reset and we do a full binary search in the next non-empty level's LevelFilesBrief. However, under the conditions https://github.com/facebook/rocksdb/issues/1 and https://github.com/facebook/rocksdb/issues/2 listed above, only the first of the duplicates has its next-level search bounds updated, and the remaining duplicates are skipped.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12295
Test Plan: Add unit tests that fail an assertion or return wrong result without the fix
Reviewed By: hx235
Differential Revision: D53187634
Pulled By: anand1976
fbshipit-source-id: a5eadf4fede9bbdec784cd993b15e3341436d1ea
Summary:
`check_flush_compaction_key_order` option was introduced for the key order checking online validation. It gave users the ability to disable the validation without downgrade in case the validation caused inefficiencies or false positives. Over time this validation has shown to be cheap and correct, so the option to disable it can now be removed.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12311
Reviewed By: cbi42
Differential Revision: D53233379
Pulled By: ajkr
fbshipit-source-id: 1384361104021d6e3e580dce2ec123f9f99ce637
Summary:
We should be consistent in how we check key range overlap in memtables and in sst files. While all the sst file key range overlap check compares the user key without timestamp, for example:
377eee77f8/db/version_set.cc (L129-L130)
This key range overlap check for memtable is comparing the whole user key. Currently it happen to achieve the same effect because this function is only called by `ExternalSstFileIngestionJob` and `DBImpl::CompactRange`, which takes a user key without timestamp as the range end, pad a max or min timestamp to it depending on whether the end is exclusive. So use `Compartor::Compare` here is working too, but we should update it to `Comparator::CompareWithoutTimestamp` to be consistent with all the other file key range overlapping check functions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12315
Test Plan: existing tests
Reviewed By: ltamasi
Differential Revision: D53273456
Pulled By: jowlyzhang
fbshipit-source-id: c094ae1f0c195d52542124c4fb03fdca14241e85
Summary:
To stop spamming our warning logs with normal behavior.
Also fix comment on `DisableFileDeletions()`.
In response to https://github.com/facebook/rocksdb/issues/12001 I've indicated my objection to granting legitimacy to force=true, but I'm not addressing that here and now. In short, the user shouldn't be asked to think about whether they want to use the *wrong* behavior. ;)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12310
Test Plan: existing tests
Reviewed By: jowlyzhang
Differential Revision: D53233117
Pulled By: pdillinger
fbshipit-source-id: 5d2aedb76b02b30f8a5fa5b436fc57fde5d40d6e
Summary:
RocksDB self throttles per-DB compaction parallelism until it detects compaction pressure. This PR adds pressure detection based on the number of files marked for compaction.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12306
Reviewed By: cbi42
Differential Revision: D53200559
Pulled By: ajkr
fbshipit-source-id: 63402ee336881a4539204d255960f04338ab7a0e
Summary:
and also fix comment/label on some MacOS CI jobs. Motivated by a crash test failure missing a definitive indicator of the genesis of the status:
```
file ingestion error: Operation failed. Try again.:
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12307
Test Plan: just cosmetic changes. These statuses should not arise frequently enough to be a performance issue (copying messages).
Reviewed By: jaykorean
Differential Revision: D53199529
Pulled By: pdillinger
fbshipit-source-id: ad83daaa5d80f75c9f81158e90fb6d9ecca33fe3
Summary:
As titled, the replacement tickers have been introduced in https://github.com/facebook/rocksdb/issues/11509 and in use since release 8.4. This PR completely removes the misspelled ones.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12302
Test Plan: CI tests
Reviewed By: jaykorean
Differential Revision: D53196935
Pulled By: jowlyzhang
fbshipit-source-id: 9c9d0d321247690db5edfdc52b4fecb2f1218979
Summary:
For the user defined timestamps in memtable only feature, some special handling for range deletion blocks are needed since both the key (start_key) and the value (end_key) of a range tombstone can contain user-defined timestamps. Handling for the key is taken care of in the same way as the other data blocks in the block based table. This PR adds the special handling needed for the value (end_key) part. This includes:
1) On the write path, when L0 SST files are first created from flush, user-defined timestamps are removed from an end key of a range tombstone. There are places where it's logically removed (replaced with a min timestamp) because there is still logic with the running comparator that expects a user key that contains timestamp. And in the block based builder, it is eventually physically removed before persisted in a block.
2) On the read path, when range deletion block is being read, we artificially pad a min timestamp to the end key of a range tombstone in `BlockBasedTableReader`.
3) For file boundary `FileMetaData.largest`, we artificially pad a max timestamp to it if it contains a range deletion sentinel. Anytime when range deletion end_key is used to update file boundaries, it's using max timestamp instead of the range tombstone's actual timestamp to mark it as an exclusive end. d69628e6ce/db/dbformat.h (L923-L935)
This max timestamp is removed when in memory `FileMetaData.largest` is persisted into Manifest, we pad it back when it's read from Manifest while handling related `VersionEdit` in `VersionEditHandler`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12254
Test Plan: Added unit test and enabled this feature combination's stress test.
Reviewed By: cbi42
Differential Revision: D52965527
Pulled By: jowlyzhang
fbshipit-source-id: e8315f8a2c5268e2ae0f7aec8012c266b86df985
Summary:
In C++, `extern` is redundant in a number of cases:
* "Global" function declarations and definitions
* "Global" variable definitions when already declared `extern`
For consistency and simplicity, I've removed these in code that *we own*. In a couple of cases, I removed obsolete declarations, and for MagicNumber constants, I have consolidated the declarations into a header file (format.h)
as standard best practice would prescribe.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12300
Test Plan: no functional changes, CI
Reviewed By: ajkr
Differential Revision: D53148629
Pulled By: pdillinger
fbshipit-source-id: fb8d927959892e03af09b0c0d542b0a3b38fd886
Summary:
... to include the actual numbers of processed and expected records, and the file number for input files. The purpose is to be able to find the offending files even when the relevant LOG file is gone.
Another change is to check the record count even when `compaction_verify_record_count` is false, and log a warning message without setting corruption status if there is a mismatch. This is consistent with how we check the record count for flush.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12297
Test Plan:
print the status message in `DBCompactionTest.VerifyRecordCount`
```
before
Corruption: Compaction number of input keys does not match number of keys processed.
after
Compaction number of input keys does not match number of keys processed. Expected 20 but processed 10. Compaction summary: Base version 4 Base level 0, inputs: [11(2156B) 9(2156B)]
```
Reviewed By: ajkr
Differential Revision: D53110130
Pulled By: cbi42
fbshipit-source-id: 6325cbfb8f71f25ce37f23f8277ebe9264863c3b
Summary:
https://github.com/facebook/rocksdb/issues/12267 apparently introduced a data race in test code where a background read of estimated_compaction_needed_bytes while holding the DB mutex could race with forground write for testing purposes. This change adds the DB mutex to those writes.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12294
Test Plan: 1000 TSAN runs of test (massively fails before change, passes after)
Reviewed By: ajkr
Differential Revision: D53095483
Pulled By: pdillinger
fbshipit-source-id: 13fcb383ebad313dabe39eb8f9085c34d370b54a
Summary:
**Context/Summary:**
We recently found out some code paths in flush and compaction aren't rate-limited when they should.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12290
Test Plan: existing UT**
Reviewed By: anand1976
Differential Revision: D53066103
Pulled By: hx235
fbshipit-source-id: 9dc4cab5f841230d18e5504dc480ac523e9d3950
Summary:
After https://github.com/facebook/rocksdb/issues/12253 this function has crashed in the crash test, in its call to `std::copy`. I haven't reproduced the crash directly, but `std::copy` probably has undefined behavior if the starting iterator is after the ending iterator, which was possible. I've fixed the logic to deal with that case and to add an assertion to check that precondition of `std::copy` (which appears can be unchecked by `std::copy` itself even with UBSAN+ASAN).
Also added some unit tests etc. that were unfinished for https://github.com/facebook/rocksdb/issues/12253, and slightly tweak SeqnoToTimeMapping::EnforceMaxTimeSpan handling of zero time span case.
This is intended for patching 8.11.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12293
Test Plan: tests added. Will trigger ~20 runs of the crash test job that saw the crash. https://fburl.com/ci/5iiizvfa
Reviewed By: jowlyzhang
Differential Revision: D53090422
Pulled By: pdillinger
fbshipit-source-id: 69d60b1847d9c7e4ae62b153011c2040405db461
Summary:
The test has been failing with
```
[ RUN ] DBCompactionTest.BottomPriCompactionCountsTowardConcurrencyLimit
db/db_compaction_test.cc:9661: Failure
Expected equality of these values:
0u
Which is: 0
env_->GetThreadPoolQueueLen(Env::Priority::LOW)
Which is: 1
```
This can happen when thread pool queue len is checked before `test::SleepingBackgroundTask::DoSleepTask` is scheduled.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12289
Reviewed By: ajkr
Differential Revision: D53064300
Pulled By: cbi42
fbshipit-source-id: 9ed1b714243880f82bd1cc1584b402ac9cf57507
Summary:
While ingesting multiple external files with key range overlap, current flow go through the lsm tree to do a search for a target level and later discard that result by defaulting back to L0. This PR improves this by just skip the search altogether.
The other change is to remove default to L0 for the combination of universal compaction + force global sequence number, which was initially added to meet a pre https://github.com/facebook/rocksdb/issues/7421 invariant.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12284
Test Plan:
Added unit test:
./external_sst_file_test --gtest_filter="*IngestFileWithGlobalSeqnoAssignedUniversal*"
Reviewed By: ajkr
Differential Revision: D53072238
Pulled By: jowlyzhang
fbshipit-source-id: 30943e2e284a7f23b495c0ea4c80cb166a34a8ac
Summary:
Seen in build-macos-cmake:
```
Received signal 11 (Segmentation fault: 11)
https://github.com/facebook/rocksdb/issues/1 rocksdb::MockSystemClock::InstallTimedWaitFixCallback()::$_0::operator()(void*) const (in seqno_time_test) (mock_time_env.cc:29)
https://github.com/facebook/rocksdb/issues/2 decltype(std::declval<rocksdb::MockSystemClock::InstallTimedWaitFixCallback()::$_0&>()(std::declval<void*>())) std::__1::__invoke[abi:v15006]<rocksdb::MockSystemClock::InstallTimedWaitFixCallback()::$_0&, void*>(rocksdb::MockSystemClock::InstallTimedWait ixCallback()::$_0&, void*&&) (in seqno_time_test) (invoke.h:394)
...
```
This is presumably because the std::function from the lambda only saves a copy of the SeqnoTimeTest* this pointer, which doesn't prevent it from being reclaimed on parallel shutdown. If we instead save a copy of the `std::shared_ptr<MockSystemClock>` in the std::function, this should prevent the crash. (Note that in `SyncPoint::Data::Process()` copies the std::function before releasing the mutex for calling the callback.)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12282
Test Plan: watch CI
Reviewed By: cbi42
Differential Revision: D53027136
Pulled By: pdillinger
fbshipit-source-id: 26cd9c0352541d806d42bb061dd349d3b47171a5
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12278
`-Wextra-semi` or `-Wextra-semi-stmt`
If the code compiles, this is safe to land.
Reviewed By: jaykorean
Differential Revision: D52969116
fbshipit-source-id: 8cb28dafdbede54e8cb59c2b8d461b1eddb3de68
Summary:
The test is [flaky](https://github.com/facebook/rocksdb/actions/runs/7616272304/job/20742657041?pr=12257&fbclid=IwAR1vNI1rSRVKnOsXs0WCPklqTkBXxlwS1GMJgWWe7D8dtAvh6e6wxk067FY) but I could not reproduce the test failure. Add some debug print to make the next failure more helpful
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12268
Test Plan:
```
check print works when test fails:
[ RUN ] DBTestWithParam/DBTestWithParam.ThreadStatusSingleCompaction/0
thread id: 6134067200, thread status:
thread id: 6133493760, thread status: Compaction
db/db_test.cc:4680: Failure
Expected equality of these values:
op_count
Which is: 1
expected_count
Which is: 0
```
Reviewed By: hx235
Differential Revision: D52987503
Pulled By: cbi42
fbshipit-source-id: 33b369796f9b97155578b45167e722ddcde93594
Summary:
This PR adds estimated pending compaction bytes in two places:
- The "Level summary", which is printed to the info LOG after every flush or compaction
- The "rocksdb.cfstats" property, which is printed to the info LOG periodically according to `stats_dump_period_sec`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12267
Test Plan:
Ran `./db_bench -benchmarks=filluniquerandom -stats_dump_period_sec=1 -statistics=true -write_buffer_size=524288` and looked at the LOG.
```
** Compaction Stats [default] **
...
Estimated pending compaction bytes: 12117691
...
2024/01/22-13:15:12.283563 1572872 (Original Log Time 2024/01/22-13:15:12.283540) [/db_impl/db_impl_compaction_flush.cc:371] [default] Level summary: files[10 1 0 0 0 0 0] max score 0.50, estimated pending compaction bytes 12359137
```
Reviewed By: cbi42
Differential Revision: D52973337
Pulled By: ajkr
fbshipit-source-id: c4e546bd9bdac387eebeeba303d04125212037b8
Summary:
This is a non functional refactor, mostly for deduplicating the stats recording logic in error handler. Plus some documentation update and simple code dedupe.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11992
Test Plan: existing tests
Reviewed By: hx235
Differential Revision: D52967713
Pulled By: jowlyzhang
fbshipit-source-id: d584eae1a06410438f5a4c59c2cb67666ea7de1a
Summary:
introduce a new option `intra_l0_compaction_size` to allow more intra-L0 compaction when total L0 size is under a threshold. This option applies only to leveled compaction. It is enabled by default and set to `max_bytes_for_level_base / max_bytes_for_level_multiplier` only for atomic_flush users. When atomic_flush=true, it is more likely that some CF's total L0 size is small when it's eligible for compaction. This option aims to reduce write amplification in this case.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12214
Test Plan:
- new unit test
- benchmark:
```
TEST_TMPDIR=/dev/shm ./db_bench --benchmarks=fillrandom --write_buffer_size=51200 --max_bytes_for_level_base=5242880 --level0_file_num_compaction_trigger=4 --statistics=1
main:
fillrandom : 234.499 micros/op 4264 ops/sec 234.499 seconds 1000000 operations; 0.5 MB/s
rocksdb.compact.read.bytes COUNT : 1490756235
rocksdb.compact.write.bytes COUNT : 1469056734
rocksdb.flush.write.bytes COUNT : 71099011
branch:
fillrandom : 128.494 micros/op 7782 ops/sec 128.494 seconds 1000000 operations; 0.9 MB/s
rocksdb.compact.read.bytes COUNT : 807474156
rocksdb.compact.write.bytes COUNT : 781977610
rocksdb.flush.write.bytes COUNT : 71098785
```
Reviewed By: ajkr
Differential Revision: D52637771
Pulled By: cbi42
fbshipit-source-id: 4f2c7925d0c3a718635c948ea0d4981ed9fabec3
Summary:
The SeqnoToTimeMapping class (RocksDB internal) used by the preserve_internal_time_seconds / preclude_last_level_data_seconds options was essentially in a prototype state with some significant flaws that would risk biting us some day. This is a big, complicated change because both the implementation and the behavioral requirements of the class needed to be upgraded together. In short, this makes SeqnoToTimeMapping more internally responsible for maintaining good invariants, so that callers don't easily encounter dangerous scenarios.
* Some API functions were confusingly named and structured, so I fully refactored the APIs to use clear naming (e.g. `DecodeFrom` and `CopyFromSeqnoRange`), object states, function preconditions, etc.
* Previously the object could informally be sorted / compacted or not, and there was limited checking or enforcement on these states. Now there's a well-defined "enforced" state that is consistently checked in debug mode for applicable operations. (I attempted to create a separate "builder" class for unenforced states, but IIRC found that more cumbersome for existing uses than it was worth.)
* Previously operations would coalesce data in a way that was better for `GetProximalTimeBeforeSeqno` than for `GetProximalSeqnoBeforeTime` which is odd because the latter is the only one used by DB code currently (what is the seqno cut-off for data definitely older than this given time?). This is now reversed to consistently favor `GetProximalSeqnoBeforeTime`, with that logic concentrated in one place: `SeqnoToTimeMapping::SeqnoTimePair::Merge()`. Unfortunately, a lot of unit test logic was specifically testing the old, suboptimal behavior.
* Previously, the natural behavior of SeqnoToTimeMapping was to THROW AWAY data needed to get reasonable answers to the important `GetProximalSeqnoBeforeTime` queries. This is because SeqnoToTimeMapping only had a FIFO policy for staying within the entry capacity (except in aggregate+sort+serialize mode). If the DB wasn't extremely careful to avoid gathering too many time mappings, it could lose track of where the seqno cutoff was for cold data (`GetProximalSeqnoBeforeTime()` returning 0) and preventing all further data migration to the cold tier--until time passes etc. for mappings to catch up with FIFO purging of them. (The problem is not so acute because SST files contain relevant snapshots of the mappings, but the problem would apply to long-lived memtables.)
* Now the SeqnoToTimeMapping class has fully-integrated smarts for keeping a sufficiently complete history, within capacity limits, to give good answers to `GetProximalSeqnoBeforeTime` queries.
* Fixes old `// FIXME: be smarter about how we erase to avoid data falling off the front prematurely.`
* Fix an apparent bug in how entries are selected for storing into SST files. Previously, it only selected entries within the seqno range of the file, but that would easily leave a gap at the beginning of the timeline for data in the file for the purposes of answering GetProximalXXX queries with reasonable accuracy. This could probably lead to the same problem discussed above in naively throwing away entries in FIFO order in the old SeqnoToTimeMapping. The updated testing of GetProximalSeqnoBeforeTime in BasicSeqnoToTimeMapping relies on the fixed behavior.
* Fix a potential compaction CPU efficiency/scaling issue in which each compaction output file would iterate over and sort all seqno-to-time mappings from all compaction input files. Now we distill the input file entries to a constant size before processing each compaction output file.
Intended follow-up (me or others):
* Expand some direct testing of SeqnoToTimeMapping APIs. Here I've focused on updating existing tests to make sense.
* There are likely more gaps in availability of needed SeqnoToTimeMapping data when the DB shuts down and is restarted, at least with WAL.
* The data tracked in the DB could be kept more accurate and limited if it used the oldest seqno of unflushed data. This might require some more API refactoring.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12253
Test Plan: unit tests updated
Reviewed By: jowlyzhang
Differential Revision: D52913733
Pulled By: pdillinger
fbshipit-source-id: 020737fcbbe6212f6701191a6ab86565054c9593
Summary:
We saw failures like
```
db/perf_context_test.cc:952: Failure
Expected: (next_count) > (count), actual: 26699 vs 26699
```
I can repro by running the test repeatedly and the test fails with different seek keys. So
the cause is likely not with Seek() implementation. I found that
`clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ts);` can return the same time when
called repeatedly. However, I don't know if Seek() is fast enough that this happened during
continuous test.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12252
Test Plan: `gtest_parallel.py --repeat=10000 --workers=1 ./perf_context_test --gtest_filter="PerfContextTest.CPUTimer"`
Reviewed By: ajkr
Differential Revision: D52912751
Pulled By: cbi42
fbshipit-source-id: 8985ae93baa99cdf4b9136ea38addd2e41f4b202
Summary:
Add asserts to help debug a crash test failure. The test fails as wollows -
```rocksdb::FilePickerMultiGet::PrepareNextLevel(): Assertion `fp_ctx.search_right_bound == -1 || fp_ctx.search_right_bound == FileIndexer::kLevelMaxIndex' failed```
Also add a unit test to verify an edge case.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12241
Reviewed By: cbi42
Differential Revision: D52819029
Pulled By: anand1976
fbshipit-source-id: 33316985c8ace1aed9ecc2400da8b777aec488ff
