Summary:
This is the initial step in the development of a lock-free clock cache. This PR includes the base hash table design (which we mostly ported over from FastLRUCache) and the clock eviction algorithm. Importantly, it's still _not_ lock-free---all operations use a shard lock. Besides the locking, there are other features left as future work:
- Remove keys from the handles. Instead, use 128-bit bijective hashes of them for handle comparisons, probing (we need two 32-bit hashes of the key for double hashing) and sharding (we need one 6-bit hash).
- Remove the clock_usage_ field, which is updated on every lookup. Even if it were atomically updated, it could cause memory invalidations across cores.
- Middle insertions into the clock list.
- A test that exercises the clock eviction policy.
- Update the Java API of ClockCache and Java calls to C++.
Along the way, we improved the code and comments quality of FastLRUCache. These changes are relatively minor.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10273
Test Plan: ``make -j24 check``
Reviewed By: pdillinger
Differential Revision: D37522461
Pulled By: guidotag
fbshipit-source-id: 3d70b737dbb70dcf662f00cef8c609750f083943
Summary:
`GetWindowsErrSz` may assign a `nullptr` to `std::string` in the event it cannot format the error code to a string. This will result in a crash when `std::string` attempts to calculate the length from `nullptr`.
The change here checks the output from `FormatMessageA` and only assigns to the otuput `std::string` if it is not null. Additionally, the call to free the buffer is only made if a non-null value is returned from `FormatMessageA`. In the event `FormatMessageA` does not output a string, an empty string is returned instead.
Fixes https://github.com/facebook/rocksdb/issues/10274
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10282
Reviewed By: riversand963
Differential Revision: D37542143
Pulled By: ajkr
fbshipit-source-id: c21f5119ddb451f76960acec94639d0f538052f2
Summary:
Currently, when installing a new super version, when stalling condition triggers, we compare estimated compaction bytes to previously, and if the new value is larger or equal to the previous one, we reduce the slowdown write rate. However, if concurrent compactions happen, the same value might be used. The result is that, although some compactions reduce estimated compaction bytes, we treat them as a signal for further slowing down. In some cases, it causes slowdown rate drops all the way to the minimum, far lower than needed.
Fix the bug by not triggering a re-calculation if a new super version doesn't have Version or a memtable change. With this fix, number of compaction finishes are still undercounted in this algorithm, but it is still better than the current bug where they are negatively counted.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10270
Test Plan: Run a benchmark where the slowdown rate is dropped to minimal unnessarily and see it is back to a normal value.
Reviewed By: ajkr
Differential Revision: D37497327
fbshipit-source-id: 9bca961cc38fed965c3af0fa6c9ca0efaa7637c4
Summary:
Resolves https://github.com/facebook/rocksdb/issues/9761
With this PR, applications can create an iterator with the following
```cpp
ReadOptions read_opts;
read_opts.timestamp = &ts_ub;
read_opts.iter_start_ts = &ts_lb;
auto* it = db->NewIterator(read_opts);
it->SeekToLast();
// or it->SeekForPrev("foo");
it->Prev();
...
```
The application can access different versions of the same user key via `key()`, `value()`, and `timestamp()`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10200
Test Plan: make check
Reviewed By: ltamasi
Differential Revision: D37258074
Pulled By: riversand963
fbshipit-source-id: 3f0b866ade50dcff7ef60d506397a9dd6ec91565
Summary:
Most of the properties listed as required for prefix extractors
are not really required but offer some conveniences. This updates API
comments to clarify actual requirements, and adds tests to demonstrate
how previously presumed requirements can be safely violated.
This might seem like a useless exercise, but this relaxing of requirements
would be needed if we generalize prefixes to group keys not just at the
byte level but also based on bits or arbitrary value ranges. For
applications without a "natural" prefix size, having only byte-level
granularity often means one prefix size to the next differs in magnitude
by a factor of 256.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10245
Test Plan: Tests added, also covering missing Iterator cases from https://github.com/facebook/rocksdb/issues/10244
Reviewed By: bjlemaire
Differential Revision: D37371559
Pulled By: pdillinger
fbshipit-source-id: ab2dd719992eea7656e9042cf8542393e02fa244
Summary:
We saw flakes with the following failure:
```
[ RUN ] RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/1
utilities/backup/backup_engine_test.cc:2667: Failure
Expected: (restore_time) > (0.8 * rate_limited_restore_time), actual: 48269 vs 60470.4
terminate called after throwing an instance of 'testing::internal::GoogleTestFailureException'
what(): utilities/backup/backup_engine_test.cc:2667: Failure
Expected: (restore_time) > (0.8 * rate_limited_restore_time), actual: 48269 vs 60470.4
Received signal 6 (Aborted)
t/run-backup_engine_test-RateLimiting-BackupEngineRateLimitingTestWithParam.RateLimiting-1: line 4: 1032887 Aborted (core dumped) TEST_TMPDIR=$d ./backup_engine_test --gtest_filter=RateLimiting/BackupEngineRateLimitingTestWithParam.RateLimiting/1
```
Investigation revealed we forgot to use the mock time `SystemClock` for
restore rate limiting. Then the test used wall clock time, which made
the execution of "GenericRateLimiter::Request:PostTimedWait"
non-deterministic as wall clock time might have advanced enough that
waiting was not needed.
This PR changes restore rate limiting to use
mock time, which guarantees we always execute
"GenericRateLimiter::Request:PostTimedWait". Then the assertions that
rely on times recorded inside that callback should be robust.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10271
Test Plan:
Applied the following patch which guaranteed repro before the fix.
Verified the test passes after this PR even with that patch applied.
```
diff --git a/util/rate_limiter.cc b/util/rate_limiter.cc
index f369e3220..6b3ed82fa 100644
--- a/util/rate_limiter.cc
+++ b/util/rate_limiter.cc
@@ -158,6 +158,7 @@ void GenericRateLimiter::SetBytesPerSecond(int64_t bytes_per_second) {
void GenericRateLimiter::Request(int64_t bytes, const Env::IOPriority pri,
Statistics* stats) {
+ usleep(100000);
assert(bytes <= refill_bytes_per_period_.load(std::memory_order_relaxed));
bytes = std::max(static_cast<int64_t>(0), bytes);
TEST_SYNC_POINT("GenericRateLimiter::Request");
```
Reviewed By: hx235
Differential Revision: D37499848
Pulled By: ajkr
fbshipit-source-id: fd790d5a192996be8ba13b656751ccc7d8cb8f6e
Summary:
The `bytes_read` returned by the current BlobSource interface is ambiguous. The uncompressed blob size is returned if the cache hits. The size of the blob read from disk, presumably the compressed version, is returned if the cache misses. Two differing semantics might cause ambiguity and consistency issues. For example, this inconsistency causes the assertion failure (T124246362 and its hot fix is https://github.com/facebook/rocksdb/issues/10249).
This goal is to require that the value of `byte read` always be an on-disk blob record size.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10248
Reviewed By: ltamasi
Differential Revision: D37470292
Pulled By: gangliao
fbshipit-source-id: fbca521b2791d3674dbf2484cea5fcae2fdd94d2
Summary:
The patch fixes a couple of issues related to in-place updates: 1) the value type was not passed from
`MemTableInserter::PutCFImpl` to `MemTable::Update` and 2) `MemTable::UpdateCallback` was called
for any value type (with the callee's logic assuming `kTypeValue`) even though the callback mechanism
is only safe for plain values.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10254
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D37463644
Pulled By: ltamasi
fbshipit-source-id: 33802477dac0691681f416ae84c4d9742c6fe41a
Summary:
Before this PR, when user-defined timestamp is enabled, db_stress disables compaction filter.
This is no longer necessary after this PR, since the `DbStressCompactionFilter` is now aware of
the presence of timestamps.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10259
Test Plan: TEST_TMPDIR=/dev/shm make crash_test_with_ts
Reviewed By: ajkr
Differential Revision: D37459692
Pulled By: riversand963
fbshipit-source-id: 8fe62e90a63bd9317fe1bb95a2b4984080c9e5ef
Summary:
The patch builds on https://github.com/facebook/rocksdb/pull/9915 and adds
a new API called `PutEntity` that can be used to write a wide-column entity
to the database. The new API is added to both `DB` and `WriteBatch`. Note
that currently there is no way to retrieve these entities; more precisely, all
read APIs (`Get`, `MultiGet`, and iterator) return `NotSupported` when they
encounter a wide-column entity that is required to answer a query. Read-side
support (as well as other missing functionality like `Merge`, compaction filter,
and timestamp support) will be added in later PRs.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10242
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D37369748
Pulled By: ltamasi
fbshipit-source-id: 7f5e412359ed7a400fd80b897dae5599dbcd685d
Summary:
Need to disable it for now as CI is failing, particularly `MultiOpsTxnsStressTest`. Investigation details in internal task T124324915. This PR disables mempurge more widely than `MultiOpsTxnsStressTest` until we know the issue is contained to that particular test.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10252
Reviewed By: riversand963
Differential Revision: D37432948
Pulled By: ajkr
fbshipit-source-id: d0cf5b0e0ec7c3142c382a0347f35a4c34f4607a
Summary:
With https://github.com/facebook/rocksdb/pull/9996 , we can pass the rate_limiter_priority to FS for most cases. This PR is to update the code path for filter block reader.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10251
Test Plan: Current unit tests should pass.
Reviewed By: pdillinger
Differential Revision: D37427667
Pulled By: gitbw95
fbshipit-source-id: 1ce5b759b136efe4cfa48a6b97e2f837ff087433
Summary:
The 'PersistRoundRobinCompactCursor' unit test in `db_compaction_test` may occasionally fail due to the inconsistent LSM state. The issue is fixed by adding `Flush()` and `WaitForFlushMemTable()` to produce a more predictable and stable LSM state.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10250
Test Plan: 'PersistRoundRobinCompactCursor' unit test in `db_compaction_test`
Reviewed By: jay-zhuang, riversand963
Differential Revision: D37426091
Pulled By: littlepig2013
fbshipit-source-id: 56fbaab0384c380c1f279a16dc8732b139c9f611
Summary:
Currently SortFileByOverlappingRatio() is O(nlogn). It is usually OK but When there are a lot of files in an LSM-tree, SortFileByOverlappingRatio() can take non-trivial amount of time. The problem is severe when the user is loading keys in sorted order, where compaction is only trivial move and this operation becomes the bottleneck and limit the total throughput. This commit makes SortFileByOverlappingRatio() only find the top 50 files based on score. 50 files are usually enough for the parallel compactions needed for the level, and in case it is not enough, we would fall back to random, which should be acceptable.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10161
Test Plan:
Run a fillseq that generates a lot of files, and observe throughput improved (although stall is not yet eliminated). The command ran:
TEST_TMPDIR=/dev/shm/ ./db_bench_sort --benchmarks=fillseq --compression_type=lz4 --write_buffer_size=5000000 --num=100000000 --value_size=1000
The throughput improved by 11%.
Reviewed By: jay-zhuang
Differential Revision: D37129469
fbshipit-source-id: 492da2ef5bfc7cdd6daa3986b50d2ff91f88542d
Summary:
This task is to fix assertion failures during the crash test runs. The cache entry size might not match value size because value size can include the on-disk (possibly compressed) size. Therefore, we removed the assertions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10249
Reviewed By: ltamasi
Differential Revision: D37407576
Pulled By: gangliao
fbshipit-source-id: 577559f267c5b2437bcd0631cd0efabb6dde3b69
Summary:
Resolves https://github.com/facebook/rocksdb/issues/10129
I extracted this fix from https://github.com/facebook/rocksdb/issues/7516 since it's also already a bug in main branch, and we want to
separate it from the main part of the PR.
There can be a race condition between two threads. Thread 1 executes
`DBImpl::FindObsoleteFiles()` while thread 2 executes `GetSortedWals()`.
```
Time thread 1 thread 2
| mutex_.lock
| read disable_delete_obsolete_files_
| ...
| wait on log_sync_cv and release mutex_
| mutex_.lock
| ++disable_delete_obsolete_files_
| mutex_.unlock
| mutex_.lock
| while (pending_purge_obsolete_files > 0) { bg_cv.wait;}
| wake up with mutex_ locked
| compute WALs tracked by MANIFEST
| mutex_.unlock
| wake up with mutex_ locked
| ++pending_purge_obsolete_files_
| mutex_.unlock
|
| delete obsolete WAL
| WAL missing but tracked in MANIFEST.
V
```
The fix proposed eliminates the possibility of the above by increasing
`pending_purge_obsolete_files_` before `FindObsoleteFiles()` can possibly release the mutex.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10187
Test Plan: make check
Reviewed By: ltamasi
Differential Revision: D37214235
Pulled By: riversand963
fbshipit-source-id: 556ab1b58ae6d19150169dfac4db08195c797184
Summary:
Add suggest_compact_range() and suggest_compact_range_cf() to C API.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10175
Test Plan:
As verifying the result requires SyncPoint, which is not available in the c_test.c,
the test is currently done by invoking the functions and making sure it does not crash.
Reviewed By: jay-zhuang
Differential Revision: D37305191
Pulled By: ajkr
fbshipit-source-id: 0fe257b45914f6c9aeb985d8b1820dafc57a20db
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
Summary:
There is currently no caching mechanism for blobs, which is not ideal especially when the database resides on remote storage (where we cannot rely on the OS page cache). As part of this task, we would like to make it possible for the application to configure a blob cache.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10225
Test Plan:
Add test cases for MultiGetBlob
In this task, we added the new API MultiGetBlob() for BlobSource.
This PR is a part of https://github.com/facebook/rocksdb/issues/10156
Reviewed By: ltamasi
Differential Revision: D37358364
Pulled By: gangliao
fbshipit-source-id: aff053a37615d96d768fb9aedde17da5618c7ae6
Summary:
cache_bench wasn't generating 16B keys, which are necessary for FastLRUCache. Also:
- Added asserts in cache_bench, which is assuming that inserts never fail. When they fail (for example, if we used keys of the wrong size), memory allocated to the values will becomes leaked, and eventually the program crashes.
- Move kCacheKeySize to the right spot.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10234
Test Plan:
``make -j24 check``. Also, run cache_bench with FastLRUCache and check that memory usage doesn't blow up:
``./cache_bench -cache_type=fast_lru_cache -num_shard_bits=6 -skewed=true \
-lookup_insert_percent=100 -lookup_percent=0 -insert_percent=0 -erase_percent=0 \
-populate_cache=true -cache_size=1073741824 -ops_per_thread=10000000 \
-value_bytes=8192 -resident_ratio=1 -threads=16``
Reviewed By: pdillinger
Differential Revision: D37382949
Pulled By: guidotag
fbshipit-source-id: b697a942ebb215de5d341f98dc8566763436ba9b
Summary:
When a key is "out of domain" for the prefix_extractor (no
prefix assigned) then the Bloom filter is not queried. PerfContext
was counting this as a Bloom "hit" while Statistics doesn't count this
as a prefix Bloom checked. I think it's more accurate to call it neither
hit nor miss, so changing the counting to make it PerfContext coounting
more like Statistics.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10244
Test Plan:
tests updates and expanded (Get and MultiGet). Iterator test
coverage of the change will come in next PR
Reviewed By: bjlemaire
Differential Revision: D37371297
Pulled By: pdillinger
fbshipit-source-id: fed132fba6a92b2314ab898d449fce2d1586c157
Summary:
**Summary**
Make the mempurge option flag a Mutable Column Family option flag. Therefore, the mempurge feature can be dynamically toggled.
**Motivation**
RocksDB users prefer having the ability to switch features on and off without having to close and reopen the DB. This is particularly important if the feature causes issues and needs to be turned off. Dynamically changing a DB option flag does not seem currently possible.
Moreover, with this new change, the MemPurge feature can be toggled on or off independently between column families, which we see as a major improvement.
**Content of this PR**
This PR includes removal of the `experimental_mempurge_threshold` flag as a DB option flag, and its re-introduction as a `MutableCFOption` flag. I updated the code to handle dynamic changes of the flag (in particular inside the `FlushJob` file). Additionally, this PR includes a new test to demonstrate the capacity of the code to toggle the MemPurge feature on and off, as well as the addition in the `db_stress` module of 2 different mempurge threshold values (0.0 and 1.0) that can be randomly changed with the `set_option_one_in` flag. This is useful to stress test the dynamic changes.
**Benchmarking**
I will add numbers to prove that there is no performance impact within the next 12 hours.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10011
Reviewed By: pdillinger
Differential Revision: D36462357
Pulled By: bjlemaire
fbshipit-source-id: 5e3d63bdadf085c0572ecc2349e7dd9729ce1802
Summary:
In order to facilitate correctness and performance testing, we would like to add the new blob cache to our stress test tool `db_stress` and our continuously running crash test script `db_crashtest.py`, as well as our synthetic benchmarking tool `db_bench` and the BlobDB performance testing script `run_blob_bench.sh`.
As part of this task, we would also like to utilize these benchmarking tools to get some initial performance numbers about the effectiveness of caching blobs.
This PR is a part of https://github.com/facebook/rocksdb/issues/10156
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10202
Reviewed By: ltamasi
Differential Revision: D37325739
Pulled By: gangliao
fbshipit-source-id: deb65d0d414502270dd4c324d987fd5469869fa8
Summary:
* Add metadata related structs and functions in C API, including
- `rocksdb_get_column_family_metadata()` and `rocksdb_get_column_family_metadata_cf()`
that returns `rocksdb_column_family_metadata_t`.
- `rocksdb_column_family_metadata_t` and its get functions & destroy function.
- `rocksdb_level_metadata_t` and its and its get functions & destroy function.
- `rocksdb_file_metadata_t` and its and get functions & destroy functions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10207
Test Plan:
Extend the existing c_test.c to include additional checks for column_family_metadata
inside CheckCompaction.
Reviewed By: riversand963
Differential Revision: D37305209
Pulled By: ajkr
fbshipit-source-id: 0a5183206353acde145f5f9b632c3bace670aa6e
Summary:
Recently merged CI benchmark scripts were failing.
There has clearly been a major revision of the fields of benchmark output. The upload script expects and sanity-checks the existence of some fields (changes date to conform to OpenSearch format)..., so the script needs to change.
Also add a bit more exception checking to make it more obvious when this happens again.
We have deleted the existing report.tsv from the benchmark machine. An existing report.tsv is appended to by default, so that if the fields change, later rows no longer match the header. This makes for an upload that dies half way through the report file, when the format no longer matches the header.
Re-instate the config.yml for running the benchmarks, so we can once again test it in situ.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10120
Reviewed By: pdillinger
Differential Revision: D37314908
Pulled By: jay-zhuang
fbshipit-source-id: 34f5243fee694b75c6838eb55d3398e4273254b2
Summary:
Even after https://github.com/facebook/rocksdb/issues/10069, `BackupEngineTest.Concurrency` is still flaky with decreased probability of failure.
Repro steps as follows
```bash
make backup_engine_test
gtest-parallel -r 1000 -w 64 ./backup_engine_test --gtest_filter=BackupEngineTest.Concurrency
```
The first two commits of this PR demonstrate how the test is flaky. https://github.com/facebook/rocksdb/issues/10069 handles the case in which
`Rename()` file returns `IOError` with subcode `PathNotFound`, and `CreateLoggerFromOptions()`
allows the operation to succeed, as expected by the test. However, `BackupEngineTest` uses
`RemapFileSystem` on top of `ChrootFileSystem` which can return `NotFound` instead of `IOError`.
This behavior is different from `Env::Default()` which returns PathNotFound if the src of `rename()`
does not exist. We should make the behaviors of the test Env/FS match a real Env/FS.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10228
Test Plan:
```bash
make check
gtest-parallel -r 1000 -w 64 ./backup_engine_test --gtest_filter=BackupEngineTest.Concurrency
```
Reviewed By: pdillinger
Differential Revision: D37337241
Pulled By: riversand963
fbshipit-source-id: 07a53115e424467b55a731866e571f0ad4c6635d
Summary:
https://github.com/facebook/rocksdb/issues/9984 changes the behavior of RocksDB: if logger creation failed during `SanitizeOptions()`,
`DB::Open()` will fail. However, since `SanitizeOptions()` is called in `DBImpl::DBImpl()`, we cannot
directly expose the error to caller without some additional work.
This is a first version proposal which:
- Adds a new member `init_logger_creation_s` to `DBImpl` to store the result of init logger creation
- Checks the error during `DB::Open()` and return it to caller if non-ok
This is not very ideal. We can alternatively move the logger creation logic out of the `SanitizeOptions()`.
Since `SanitizeOptions()` is used in other places, we need to check whether this change breaks anything
in case other callers of `SanitizeOptions()` assumes that a logger should be created.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10223
Test Plan: make check
Reviewed By: pdillinger
Differential Revision: D37321717
Pulled By: riversand963
fbshipit-source-id: 58042358a86369d606549dd9938933dd47591c4b
Summary:
There was a bug in the MultiGet enhancement in https://github.com/facebook/rocksdb/issues/9899 with data
block hash index, which was not caught because data block hash index was
never added to stress tests. This change fixes both issues.
Fixes https://github.com/facebook/rocksdb/issues/10186
I intend to pick this into the 7.4.0 release candidate
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10220
Test Plan:
Failure quickly reproduces in crash test with
kDataBlockBinaryAndHash, and does not seem to with the fix. Reproducing
the failure with a unit test I believe would be too tricky and fragile
to be worthwhile.
Reviewed By: anand1976
Differential Revision: D37315647
Pulled By: pdillinger
fbshipit-source-id: 9f648265bba867275edc752f7a56611a59401cba
Summary:
So that DBImpl::RecoverLogFiles do not have to deal with implementation
details of WalFilter.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10214
Test Plan: make check
Reviewed By: ajkr
Differential Revision: D37299122
Pulled By: riversand963
fbshipit-source-id: acf1a80f1ef75da393d375f55968b2f3ac189816
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
Summary:
In FastLRUCache, we replace the current chained per-shard hash table by an open-addressing hash table. In particular, this allows us to preallocate all handles.
Because all handles are preallocated, this implementation doesn't support strict_capacity_limit = false (i.e., allowing insertions beyond the predefined capacity). This clashes with current assumptions of some tests, namely two tests in cache_test and the crash tests. We have disabled these for now.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10194
Test Plan: ``make -j24 check``
Reviewed By: pdillinger
Differential Revision: D37296770
Pulled By: guidotag
fbshipit-source-id: 232ff1b8260331d868ebf4e3e5d8ad709390b0ad
Summary:
There is currently no caching mechanism for blobs, which is not ideal especially when the database resides on remote storage (where we cannot rely on the OS page cache). As part of this task, we would like to make it possible for the application to configure a blob cache.
In this task, we formally introduced the blob source to RocksDB. BlobSource is a new abstraction layer that provides universal access to blobs, regardless of whether they are in the blob cache, secondary cache, or (remote) storage. Depending on user settings, it always fetch blobs from multi-tier cache and storage with minimal cost.
Note: The new `MultiGetBlob()` implementation is not included in the current PR. To go faster, we aim to create a separate PR for it in parallel!
This PR is a part of https://github.com/facebook/rocksdb/issues/10156
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10198
Reviewed By: ltamasi
Differential Revision: D37294735
Pulled By: gangliao
fbshipit-source-id: 9cb50422d9dd1bc03798501c2778b6c7520c7a1e
Summary:
One consistency check in SaveTo() is dupilcated with the one within Apply(). Remove one of then in release mode to reduce time spent in DB mutex.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10169
Test Plan: Run existing tests and see nothing breaks.
Reviewed By: ltamasi
Differential Revision: D37157821
fbshipit-source-id: 73b89443a20b43362ff66d10b9212022034a8234
Summary:
include "include/rocksdb/blah.h" is messing up some internal
builds vs. include "rocksdb/blah." This fixes the bad case and adds a
check for future instances.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10213
Test Plan: back-port to 7.4 release candidate and watch internal build
Reviewed By: hx235
Differential Revision: D37296202
Pulled By: pdillinger
fbshipit-source-id: d7cc6b2c57d858dff0444f19320d83c8b4f9b185
Summary:
This bug was discovered after write batch checksum verification before WAL is added (https://github.com/facebook/rocksdb/issues/10114) and stress test with write batch checksum protection is turned on (https://github.com/facebook/rocksdb/issues/10037). In this [line](d5d8920f2c/db/write_batch.cc (L2887)), the number of checksums may not be consistent with `batch->Count()`. This PR fixes this issue.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10201
Test Plan:
```
./db_stress --batch_protection_bytes_per_key=8 --destroy_db_initially=1 --max_key=100000 --use_txn=1
```
Reviewed By: ajkr
Differential Revision: D37260799
Pulled By: cbi42
fbshipit-source-id: ff8dce7dcce295d689333bc9d892d17a843bf0ea
Summary:
`FlushWAL(true /* sync */)` is used internally and for manual WAL sync. It had a bug when used together with `track_and_verify_wals_in_manifest` where the synced size tracked in MANIFEST was larger than the number of bytes actually synced.
The bug could be repro'd almost immediately with the following crash test command: `python3 tools/db_crashtest.py blackbox --simple --write_buffer_size=524288 --max_bytes_for_level_base=2097152 --target_file_size_base=524288 --duration=3600 --interval=10 --sync_fault_injection=1 --disable_wal=0 --checkpoint_one_in=1000 --max_key=10000 --value_size_mult=33`.
An example error message produced by the above command is shown below. The error sometimes arose from the checkpoint and other times arose from the main stress test DB.
```
Corruption: Size mismatch: WAL (log number: 119) in MANIFEST is 27938 bytes , but actually is 27859 bytes on disk.
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10185
Test Plan:
- repro unit test
- the above crash test command no longer finds the error. It does find a different error after a while longer such as "Corruption: WAL file 481 required by manifest but not in directory list"
Reviewed By: riversand963
Differential Revision: D37200993
Pulled By: ajkr
fbshipit-source-id: 98e0071c1a89f4d009888512ed89f9219779ae5f
Guido Tagliavini Ponce