Summary:
Set the perf_level in ```tools/regression_test.sh``` in order to exercise ```PerfContext``` counters in regression tests.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8031
Test Plan: Manually run the script
Reviewed By: ajkr
Differential Revision: D31508269
Pulled By: anand1976
fbshipit-source-id: 20ddfd1cbca37f1439eed2870086a86d90653b44
Summary:
The patch adds a new BlobDB benchmarking script called `run_blob_bench.sh`.
It is a thin wrapper around `benchmark.sh` (similarly to `run_flash_bench.sh`):
it actually calls `benchmark.sh` a number of times, cycling through six workloads,
two write-only ones (bulk load and overwrite), two read/write ones (point lookups
while writing, range scans while writing), and two read-only ones (point lookups
and range scans).
Note: this is a simpler/cleaned up/reworked version of the script used to produce the
benchmark results in http://rocksdb.org/blog/2021/05/26/integrated-blob-db.html .
The new version takes advantage of several recent `benchmark.sh` improvements
like the ability to pass in arbitrary `db_bench` options or the possibility of using a
job ID.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9015
Test Plan: Ran the script manually with different parameter combinations.
Reviewed By: riversand963
Differential Revision: D31555277
Pulled By: ltamasi
fbshipit-source-id: 0e151b2f7b2cf6f66ed7f95455571492ad7ea87f
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
Summary:
`FaultInjectionTest{Env,FS}::ReopenWritableFile()` functions were accidentally deleting WALs from previous `db_stress` runs causing verification to fail. They were operating under the assumption that `ReopenWritableFile()` would delete any existing file. It was a reasonable assumption considering the `{Env,FileSystem}::ReopenWritableFile()` documentation stated that would happen. The only problem was neither the implementations we offer nor the "real" clients in RocksDB code followed that contract. So, this PR updates the contract as well as fixing the fault injection client usage.
The fault injection change exposed that `ExternalSSTFileBasicTest.SyncFailure` was relying on a fault injection `Env` dropping unsynced data written by a regular `Env`. I changed that test to make its `SstFileWriter` use fault injection `Env`, and also implemented `LinkFile()` in fault injection so the unsynced data is tracked under the new name.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8995
Test Plan:
- Verified it fixes the following failure:
```
$ ./db_stress --clear_column_family_one_in=0 --column_families=1 --db=/dev/shm/rocksdb_crashtest_whitebox --delpercent=5 --expected_values_dir=/dev/shm/rocksdb_crashtest_expected --iterpercent=0 --key_len_percent_dist=1,30,69 --max_key=100000 --max_key_len=3 --nooverwritepercent=1 --ops_per_thread=1000 --prefixpercent=0 --readpercent=60 --reopen=0 --target_file_size_base=1048576 --test_batches_snapshots=0 --write_buffer_size=1048576 --writepercent=35 --value_size_mult=33 -threads=1
...
$ ./db_stress --avoid_flush_during_recovery=1 --clear_column_family_one_in=0 --column_families=1 --db=/dev/shm/rocksdb_crashtest_whitebox --delpercent=5 --destroy_db_initially=0 --expected_values_dir=/dev/shm/rocksdb_crashtest_expected --iterpercent=10 --key_len_percent_dist=1,30,69 --max_bytes_for_level_base=4194304 --max_key=100000 --max_key_len=3 --nooverwritepercent=1 --open_files=-1 --open_metadata_write_fault_one_in=8 --open_write_fault_one_in=16 --ops_per_thread=1000 --prefix_size=-1 --prefixpercent=0 --readpercent=50 --sync=1 --target_file_size_base=1048576 --test_batches_snapshots=0 --write_buffer_size=1048576 --writepercent=35 --value_size_mult=33 -threads=1
...
Verification failed for column family 0 key 000000000000001300000000000000857878787878 (1143): Value not found: NotFound:
Crash-recovery verification failed :(
...
```
- `make check -j48`
Reviewed By: ltamasi
Differential Revision: D31495388
Pulled By: ajkr
fbshipit-source-id: 7886ccb6a07cb8b78ad7b6c1c341ccf40bb68385
Summary:
Enable SingleDelete with user defined timestamp in db_bench,
db_stress and crash test
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8971
Test Plan:
1. For db_stress, ran the command for full duration: i) python3 -u tools/db_crashtest.py
--enable_ts whitebox --nooverwritepercent=100
ii) make crash_test_with_ts
2. For db_bench, ran: ./db_bench -benchmarks=randomreplacekeys
-user_timestamp_size=8 -use_single_deletes=true
Reviewed By: riversand963
Differential Revision: D31246558
Pulled By: akankshamahajan15
fbshipit-source-id: 29cd8740c9921341e52f09242fca3c44d75a12b7
Summary:
The ldb list_live_files_metadata command does not print any information about blob files currently. We would like to add this functionality. Note that list_live_files_metadata has two different modes of operation: the one shown above, which shows the LSM tree structure, and another one, which can be enabled using the flag --sort_by_filename and simply lists the files in numerical order regardless of level. We would like to show blob files in both modes.
Changes:
1. Using GetAllColumnFamilyMetaData API instead of GetLiveFilesMetaData API for fetching live files data.
Testing:
1. Created a sample rocksdb instance using dbbench command (this creates both SST and blob files)
2. Checked if the blob files are listed or not by using ldb commands.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8976
Reviewed By: ltamasi
Differential Revision: D31316061
Pulled By: pradeepambati
fbshipit-source-id: d15cdea192febf7a45f28deee2ba40615d3d84ab
Summary:
This header file was including everything and the kitchen sink when it did not need to. This resulted in many places including this header when they needed other pieces instead.
Cleaned up this header to only include what was needed and fixed up the remaining code to include what was now missing.
Hopefully, this sort of code hygiene cleanup will speed up the builds...
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8930
Reviewed By: pdillinger
Differential Revision: D31142788
Pulled By: mrambacher
fbshipit-source-id: 6b45de3f300750c79f751f6227dece9cfd44085d
Summary:
This is a precursor refactoring to enable an upcoming feature: persistence failure correctness testing.
- Changed `--expected_values_path` to `--expected_values_dir` and migrated "db_crashtest.py" to use the new flag. For persistence failure correctness testing there are multiple possible correct states since unsynced data is allowed to be dropped. Making it possible to restore all these possible correct states will eventually involve files containing snapshots of expected values and DB trace files.
- The expected values directory is managed by an `ExpectedStateManager` instance. Managing expected state files is separated out of `SharedState` to prevent `SharedState` from becoming too complex when the new files and features (snapshotting, tracing, and restoring) are introduced.
- Migrated expected values file access/management out of `SharedState` into a separate class called `ExpectedState`. This is not exposed directly to the test but rather the `ExpectedState` for the latest values file is accessed via a pass-through API on `ExpectedStateManager`. This forces the test to always access the single latest `ExpectedState`.
- Changed the initialization of the latest expected values file to use a tempfile followed by rename, and also add cleanup logic for possible stranded tempfiles.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8913
Test Plan:
run in several ways; try to make sure it's not obviously broken.
- crashtest blackbox without TEST_TMPDIR
```
$ python3 tools/db_crashtest.py blackbox --simple --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --duration=120 --interval=10 --compression_type=none --blob_compression_type=none
```
- crashtest blackbox with TEST_TMPDIR
```
$ TEST_TMPDIR=/dev/shm python3 tools/db_crashtest.py blackbox --simple --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --duration=120 --interval=10 --compression_type=none --blob_compression_type=none
```
- crashtest whitebox with TEST_TMPDIR
```
$ TEST_TMPDIR=/dev/shm python3 tools/db_crashtest.py whitebox --simple --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --duration=120 --interval=10 --compression_type=none --blob_compression_type=none --random_kill_odd=88887
```
- db_stress without expected_values_dir
```
$ ./db_stress --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --ops_per_thread=10000 --clear_column_family_one_in=0 --destroy_db_initially=true
```
- db_stress with expected_values_dir and manual corruption
```
$ ./db_stress --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --ops_per_thread=10000 --clear_column_family_one_in=0 --destroy_db_initially=true --expected_values_dir=./
// modify one byte in "./LATEST.state"
$ ./db_stress --write_buffer_size=1048576 --target_file_size_base=1048576 --max_bytes_for_level_base=4194304 --max_key=100000 --value_size_mult=33 --compression_type=none --ops_per_thread=10000 --clear_column_family_one_in=0 --destroy_db_initially=false --expected_values_dir=./
...
Verification failed for column family 0 key 0000000000000000 (0): Value not found: NotFound:
...
```
Reviewed By: riversand963
Differential Revision: D30921951
Pulled By: ajkr
fbshipit-source-id: babfe218062e55d018c9b046536c0289fb78f41c
Summary:
For now, disable it since the below command indicates it can cause a
failure. Running that command with `-experimental_mempurge_threshold=0`
has been running successfully for several minutes, whereas before it
failed in seconds.
```
$ while rm -rf /dev/shm/single_stress && ./db_stress --clear_column_family_one_in=0 --column_families=1 --db=/dev/shm/single_stress --experimental_mempurge_threshold=5.493146827397074 --flush_one_in=10000 --reopen=0 --write_buffer_size=262144 --value_size_mult=33 --max_write_buffer_number=3 -ops_per_thread=10000; do : ; done
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8958
Reviewed By: ltamasi
Differential Revision: D31187059
Pulled By: ajkr
fbshipit-source-id: 04d5bfb4fcc4f5b66233e691427dfd940c67037f
Summary:
Several improvements to MultiRead:
1. Fix a bug in stress test which causes false positive when both MultiRead() return and individual read request have failure injected.
2. Add two more types of fault that should be handled: empty read results and checksum mismatch
3. Add a message indicating which type of fault is injected
4. Increase the failure rate
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8937
Reviewed By: anand1976
Differential Revision: D31085930
fbshipit-source-id: 3a04994a3cadebf9a64d25e1fe12b14b7a272fba
Summary:
In FileChecksumTestHelper::VerifyEachFileChecksum(), we query the file list, and then for each file in the list verify the checksum. However, compaction can delete those files in the mean time and cause failures. To prevent it from happening, disable file deletion during the validation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8942
Test Plan: Run exsiting test and see it doesn't fail.
Reviewed By: pdillinger
Differential Revision: D31086488
fbshipit-source-id: 554608f36d2dd3bf0a20dfc4039c68bd8533d7f8
Summary:
In case of IO uring bugs, we need to provide a way for users to turn it off.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8931
Test Plan: Manually run db_bench with/without the option and verify the behavior
Reviewed By: pdillinger
Differential Revision: D31040252
Pulled By: anand1976
fbshipit-source-id: 56f2537d6ac8488c9e126296d8190ad9e0158f70
Summary:
As title. The reason is that after loading customized options, the env is not set back to the correct one. Fix it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8929
Test Plan: Manually validate in an environment where the command failed.
Reviewed By: riversand963
Differential Revision: D31026931
fbshipit-source-id: c25dc788bf80ed5bf4b24922c442781943bcd65b
Summary:
Because even 32-bit systems can have large files
This is a "change" that I don't want intermingled with an upcoming refactoring.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8926
Test Plan: CI
Reviewed By: zhichao-cao
Differential Revision: D31020974
Pulled By: pdillinger
fbshipit-source-id: ca9eb4510697df6f1f55e37b37730b88b1809a92
Summary:
* Started on some proper usage text to document the options
* Added a `JOB_ID` parameter, so that we can trace jobs and relate them to other assets
* Now generates a correct TSV file of the summary
* Summary has new additional fields:
* RocksDB Version
* Date
* Job ID
* db_bench log files now also include the Job ID
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8730
Reviewed By: mrambacher
Differential Revision: D30747344
Pulled By: jay-zhuang
fbshipit-source-id: 87eb78d20959b6d95804aebf129606fa9c71f407
Summary:
These tests would frequently fail to find SST files due to race
condition in running ldb (read-only) on an open DB which might do automatic
compaction. But only sometimes would that failure translate into test
failure because the implementation of ldb file_checksum_dump would
swallow many errors. Now,
* DB closed while running ldb to avoid unnecessary race condition
* Detect and report/propagate more failures in `ldb file_checksum_dump`
* Use --hex so that random binary data is not printed to console
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8898
Test Plan: ./ldb_cmd_test --gtest_filter=*Checksum* --gtest_repeat=100
Reviewed By: zhichao-cao
Differential Revision: D30848738
Pulled By: pdillinger
fbshipit-source-id: 20290b517eeceba99bb538bb5a17088f7e878405
Summary:
This allows the wrapper classes to own the wrapped object and eliminates confusion as to ownership. Previously, many classes implemented their own ownership solutions. Fixes https://github.com/facebook/rocksdb/issues/8606
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8618
Reviewed By: pdillinger
Differential Revision: D30136064
Pulled By: mrambacher
fbshipit-source-id: d0bf471df8818dbb1770a86335fe98f761cca193
Summary:
Make the Statistics object into a Customizable object. Statistics can now be stored and created to/from the Options file.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8637
Reviewed By: zhichao-cao
Differential Revision: D30530550
Pulled By: mrambacher
fbshipit-source-id: 5fc7d01d8431f37b2c205bbbd8342c9f697023bd
Summary:
This PR does the following:
-> Makes the MemTableRepFactory into a Customizable class and creatable/configurable via CreateFromString
-> Makes the existing implementations compatible with configurations
-> Moves the "SpecialRepFactory" test class into testutil, accessible via the ObjectRegistry or a NewSpecial API
New tests were added to validate the functionality and all existing tests pass. db_bench and memtablerep_bench were hand-tested to verify the functionality in those tools.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8419
Reviewed By: zhichao-cao
Differential Revision: D29558961
Pulled By: mrambacher
fbshipit-source-id: 81b7229636e4e649a0c914e73ac7b0f8454c931c
Summary:
* Don't hardcode namespace rocksdb (use ROCKSDB_NAMESPACE)
* Don't #include <rocksdb/...> (use double quotes)
* Support putting NOCOMMIT (any case) in source code that should not be
committed/pushed in current state.
These will be run with `make check` and in GitHub actions
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8821
Test Plan: existing tests, manually try out new checks
Reviewed By: zhichao-cao
Differential Revision: D30791726
Pulled By: pdillinger
fbshipit-source-id: 399c883f312be24d9e55c58951d4013e18429d92
Summary:
Regression test is broken and not running:
1. failed test is not reporting, fix it by add `set -e`
2. internal regression test is not run inside github, removing that
3. fix a few minor issues to pass the test
4. delete unused binary size build, and regression test is reporting binary size now.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8753
Test Plan: CI: https://www.internalfb.com/intern/sandcastle/job/13510799359573861
Reviewed By: ltamasi
Differential Revision: D30754380
Pulled By: jay-zhuang
fbshipit-source-id: 0cfa008327fff31bc61118a3fe642924090d28e1
Summary:
* FullKey and ParseFullKey appear to serve no purpose in the public API
(or anything else) so removed. Only use in one test updated.
* NumberToString serves no purpose vs. ToString so removed, numerous
calls updated
* Remove unnecessary forward declarations in metadata.h by re-arranging
class definitions.
* Remove some unneeded semicolons
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8736
Test Plan: existing tests
Reviewed By: mrambacher
Differential Revision: D30700039
Pulled By: pdillinger
fbshipit-source-id: 1e436a576f511a6ed8b4d97af7cc8216bc729af2
Summary:
Current implementation does not support user-defined timestamp when
block-based filter is used. Will implement the support in the future, or
wait to see if block-based filter can be deprecated and removed.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8703
Test Plan: make whitebox_crash_test_with_ts
Reviewed By: pdillinger
Differential Revision: D30528931
Pulled By: riversand963
fbshipit-source-id: 60dd74ee0a6194e69072069d8c4bd876f249f38d
Summary:
Handler functions now use a common output function to output to stdout/files.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8697
Test Plan: `trace_analyzer_test` can pass.
Reviewed By: zhichao-cao
Differential Revision: D30527696
Pulled By: autopear
fbshipit-source-id: c626cf4d53a39665a9c4bcf0cb019c448434abe4
Summary:
This is essentially resurrection and fixing of the part of
https://github.com/facebook/rocksdb/issues/8198 that was reverted in https://github.com/facebook/rocksdb/issues/8212, using data added in https://github.com/facebook/rocksdb/issues/8246. Basically,
when configuring Ribbon filter, you can specify an LSM level before which
Bloom will be used instead of Ribbon. But Bloom is only considered for
Leveled and Universal compaction styles and file going into a known LSM
level. This way, SST file writer, FIFO compaction, etc. use Ribbon filter as
you would expect with NewRibbonFilterPolicy.
So that this can be controlled with a single int value and so that flushes
can be distinguished from intra-L0, we consider flush to go to level -1 for
the purposes of this option. (Explained in API comment.)
I also expect the most common and recommended Ribbon configuration to
use Bloom during flush, to minimize slowing down writes and because according
to my estimates, Ribbon only pays off if the structure lives in memory for
more than an hour. Thus, I have changed the default for NewRibbonFilterPolicy
to be this mild hybrid configuration. I don't really want to add something like
NewHybridFilterPolicy because at least the mild hybrid configuration (Bloom for
flush, Ribbon otherwise) should be considered a natural choice.
C APIs also updated, but because they don't support overloading,
rocksdb_filterpolicy_create_ribbon is kept pure ribbon for clarity and
rocksdb_filterpolicy_create_ribbon_hybrid must be called for a hybrid
configuration. While touching C API, I changed bits per key options from
int to double.
BuiltinFilterPolicy is needed so that LevelThresholdFilterPolicy doesn't inherit
unused fields from BloomFilterPolicy.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8679
Test Plan: new + updated tests, including crash test
Reviewed By: jay-zhuang
Differential Revision: D30445797
Pulled By: pdillinger
fbshipit-source-id: 6f5aeddfd6d79f7e55493b563c2d1d2d568892e1
Summary:
`Replayer::Execute()` can directly returns the result (e.g, request latency, DB::Get() return code, returned value, etc.)
`Replayer::Replay()` reports the results via a callback function.
New interface:
`TraceRecordResult` in "rocksdb/trace_record_result.h".
`DBTest2.TraceAndReplay` and `DBTest2.TraceAndManualReplay` are updated accordingly.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8657
Reviewed By: ajkr
Differential Revision: D30290216
Pulled By: autopear
fbshipit-source-id: 3c8d4e6b180ec743de1a9d9dcaee86064c74f0d6
Summary:
New public interfaces:
`TraceRecord` and `TraceRecord::Handler`, available in "rocksdb/trace_record.h".
`Replayer`, available in `rocksdb/utilities/replayer.h`.
User can use `DB::NewDefaultReplayer()` to create a Replayer to auto/manual replay a trace file.
Unit tests:
- `./db_test2 --gtest_filter="DBTest2.TraceAndReplay"`: Updated with the internal API changes.
- `./db_test2 --gtest_filter="DBTest2.TraceAndManualReplay"`: New for manual replay.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8611
Reviewed By: ajkr
Differential Revision: D30266329
Pulled By: autopear
fbshipit-source-id: 1ecb3cbbedae0f6a67c18f0cc82e002b4d81b6f8
Summary:
The last few releases overlooked adding to this test. This
change fixes that.
This change also fixes the problem of older branches not understanding
ROCKSDB_NO_FBCODE and referencing compilers no longer supported.
During the test, build_detect_platform is patched to force no FBCODE
compiler usage. (We should not need to update old branches perpetually.)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8651
Test Plan: local run reproduces regression described in https://github.com/facebook/rocksdb/issues/8650
Reviewed By: jay-zhuang, zhichao-cao
Differential Revision: D30261872
Pulled By: pdillinger
fbshipit-source-id: 02b447d224d7e0eb8613c63185437ded146713bc
Summary:
Changes the API of the MemPurge process: the `bool experimental_allow_mempurge` and `experimental_mempurge_policy` flags have been replaced by a `double experimental_mempurge_threshold` option.
This change of API reflects another major change introduced in this PR: the MemPurgeDecider() function now works by sampling the memtables being flushed to estimate the overall amount of useful payload (payload minus the garbage), and then compare this useful payload estimate with the `double experimental_mempurge_threshold` value.
Therefore, when the value of this flag is `0.0` (default value), mempurge is simply deactivated. On the other hand, a value of `DBL_MAX` would be equivalent to always going through a mempurge regardless of the garbage ratio estimate.
At the moment, a `double experimental_mempurge_threshold` value else than 0.0 or `DBL_MAX` is opnly supported`with the `SkipList` memtable representation.
Regarding the sampling, this PR includes the introduction of a `MemTable::UniqueRandomSample` function that collects (approximately) random entries from the memtable by using the new `SkipList::Iterator::RandomSeek()` under the hood, or by iterating through each memtable entry, depending on the target sample size and the total number of entries.
The unit tests have been readapted to support this new API.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8628
Reviewed By: pdillinger
Differential Revision: D30149315
Pulled By: bjlemaire
fbshipit-source-id: 1feef5390c95db6f4480ab4434716533d3947f27
Summary:
`GenericRateLimiter` slow path handles requests that cannot be satisfied
immediately. Such requests enter a queue, and their thread stays in `Request()`
until they are granted or the rate limiter is stopped. These threads are
responsible for unblocking themselves. The work to do so is split into two main
duties.
(1) Waiting for the next refill time.
(2) Refilling the bytes and granting requests.
Prior to this PR, the slow path logic involved a leader election algorithm to
pick one thread to perform (1) followed by (2). It elected the thread whose
request was at the front of the highest priority non-empty queue since that
request was most likely to be granted. This algorithm was efficient in terms of
reducing intermediate wakeups, which is a thread waking up only to resume
waiting after finding its request is not granted. However, the conceptual
complexity of this algorithm was too high. It took me a long time to draw a
timeline to understand how it works for just one edge case yet there were so
many.
This PR drops the leader election to reduce conceptual complexity. Now, the two
duties can be performed by whichever thread acquires the lock first. The risk
of this change is increasing the number of intermediate wakeups, however, we
took steps to mitigate that.
- `wait_until_refill_pending_` flag ensures only one thread performs (1). This\
prevents the thundering herd problem at the next refill time. The remaining\
threads wait on their condition variable with an unbounded duration -- thus we\
must remember to notify them to ensure forward progress.
- (1) is typically done by a thread at the front of a queue. This is trivial\
when the queues are initially empty as the first choice that arrives must be\
the only entry in its queue. When queues are initially non-empty, we achieve\
this by having (2) notify a thread at the front of a queue (preferring higher\
priority) to perform the next duty.
- We do not require any additional wakeup for (2). Typically it will just be\
done by the thread that finished (1).
Combined, the second and third bullet points above suggest the refill/granting
will typically be done by a request at the front of its queue. This is
important because one wakeup is saved when a granted request happens to be in an
already running thread.
Note there are a few cases that still lead to intermediate wakeup, however. The
first two are existing issues that also apply to the old algorithm, however, the
third (including both subpoints) is new.
- No request may be granted (only possible when rate limit dynamically\
decreases).
- Requests from a different queue may be granted.
- (2) may be run by a non-front request thread causing it to not be granted even\
if some requests in that same queue are granted. It can happen for a couple\
(unlikely) reasons.
- A new request may sneak in and grab the lock at the refill time, before the\
thread finishing (1) can wake up and grab it.
- A new request may sneak in and grab the lock and execute (1) before (2)'s\
chosen candidate can wake up and grab the lock. Then that non-front request\
thread performing (1) can carry over to perform (2).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8602
Test Plan:
- Use existing tests. The edge cases listed in the comment are all performance\
related; I could not really think of any related to correctness. The logic\
looks the same whether a thread wakes up/finishes its work early/on-time/late,\
or whether the thread is chosen vs. "steals" the work.
- Verified write throughput and CPU overhead are basically the same with and\
without this change, even in a rate limiter heavy workload:
Test command:
```
$ rm -rf /dev/shm/dbbench/ && TEST_TMPDIR=/dev/shm /usr/bin/time ./db_bench -benchmarks=fillrandom -num_multi_db=64 -num_low_pri_threads=64 -num_high_pri_threads=64 -write_buffer_size=262144 -target_file_size_base=262144 -max_bytes_for_level_base=1048576 -rate_limiter_bytes_per_sec=16777216 -key_size=24 -value_size=1000 -num=10000 -compression_type=none -rate_limiter_refill_period_us=1000
```
Results before this PR:
```
fillrandom : 108.463 micros/op 9219 ops/sec; 9.0 MB/s
7.40user 8.84system 1:26.20elapsed 18%CPU (0avgtext+0avgdata 256140maxresident)k
```
Results after this PR:
```
fillrandom : 108.108 micros/op 9250 ops/sec; 9.0 MB/s
7.45user 8.23system 1:26.68elapsed 18%CPU (0avgtext+0avgdata 255688maxresident)k
```
Reviewed By: hx235
Differential Revision: D30048013
Pulled By: ajkr
fbshipit-source-id: 6741bba9d9dfbccab359806d725105817fef818b
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
Summary:
- Changed MergeOperator, CompactionFilter, and CompactionFilterFactory into Customizable classes.
- Added Options/Configurable/Object Registration for TTL and Cassandra variants
- Changed the StringAppend MergeOperators to accept a string delimiter rather than a simple char. Made the delimiter into a configurable option
- Added tests for new functionality
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8481
Reviewed By: zhichao-cao
Differential Revision: D30136050
Pulled By: mrambacher
fbshipit-source-id: 271d1772835935b6773abaf018ee71e42f9491af
Summary:
Prior to this change, the "wal_dir" DBOption would always be set (defaults to dbname) when the DBOptions were sanitized. Because of this setitng in the options file, it was not possible to rename/relocate a database directory after it had been created and use the existing options file.
After this change, the "wal_dir" option is only set under specific circumstances. Methods were added to the ImmutableDBOptions class to see if it is set and if it is set to something other than the dbname. Additionally, a method was added to retrieve the effective value of the WAL dir (either the option or the dbname/path).
Tests were added to the core and ldb to test that a database could be created and renamed without issue. Additional tests for various permutations of wal_dir were also added.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8582
Reviewed By: pdillinger, autopear
Differential Revision: D29881122
Pulled By: mrambacher
fbshipit-source-id: 67d3d033dc8813d59917b0a3fba2550c0efd6dfb
Summary:
Introduction of a new `fillanddeleteuniquerandom` benchmark (`db_bench`) with 5 new option flags to simulate a benchmark where the following sequence is repeated multiple times:
"A set of keys S1 is inserted ('`disposable entries`'), then after some delay another set of keys S2 is inserted ('`persistent entries`') and the first set of keys S1 is deleted. S2 artificially represents the insertion of hypothetical results from some undefined computation done on the first set of keys S1. The next sequence can start as soon as the last disposable entry in the set S1 of this sequence is inserted, if the `delay` is non negligible."
New flags:
- `disposable_entries_delete_delay`: minimum delay in microseconds between insertion of the last `disposable` entry, and the start of the insertion of the first `persistent` entry.
- `disposable_entries_batch_size`: number of `disposable` entries inserted at the beginning of each sequence.
- `disposable_entries_value_size`: size of the random `value` string for the `disposable` entries.
- `persistent_entries_batch_size`: number of `persistent` entries inserted at the end of each sequence, right before the deletion of the `disposable` entries starts.
- `persistent_entries_value_size`: size of the random value string for the `persistent` entries.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8593
Reviewed By: pdillinger
Differential Revision: D29974436
Pulled By: bjlemaire
fbshipit-source-id: f578033e5b45e8268ba6fa6f38f4770c2e6e801d
Summary:
* Basic handling of SST file with just range tombstones rather than
failing assertion about smallest_seqno <= largest_seqno
* Adds --verbose option so that there exists a way to see the INFO
output from Repairer.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8544
Test Plan: unit test added, manual testing for --verbose
Reviewed By: ajkr
Differential Revision: D29954805
Pulled By: pdillinger
fbshipit-source-id: 696af25805fc36cc178b04ba6045922a22625fd9
Summary:
Add `experimental_mempurge_policy` flag to `db_stress` and `db_crashtest.py`.
This flag is only read if the `experimental_allow_mempurge` flag is set to `true`. This flag can take the following values: `kAlways`, and `kAlternate` (default).
- `kAlways`: a flush is always redirected to a mempurge. If the mempurge aborts, the a regular flush proceeds.
- `kAlternate`: if one or more of the flush input memtables is an mempurge output memtable, then a flush is performed, else a mempurge is carried out. Similar to kAlways, if a mempurge aborts, the FlushJob proceeds to a regular flush to storage.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8588
Reviewed By: pdillinger
Differential Revision: D29934251
Pulled By: bjlemaire
fbshipit-source-id: 90c1debed2029b9915d066914556547507c33dae
Summary:
- Added Type/CreateFromString
- Added ability to load EventListeners to DBOptions
- Since EventListeners did not previously have a Name(), defaulted to "". If there is no name, the listener cannot be loaded from the ObjectRegistry.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8473
Reviewed By: zhichao-cao
Differential Revision: D29901488
Pulled By: mrambacher
fbshipit-source-id: 2d3a4aa6db1562ac03e7ad41b360e3521d486254
Summary:
Add `experimental_mempurge_policy` option flag and introduce two new `MemPurge` (Memtable Garbage Collection) policies: 'ALWAYS' and 'ALTERNATE'. Default value: ALTERNATE.
`ALWAYS`: every flush will first go through a `MemPurge` process. If the output is too big to fit into a single memtable, then the mempurge is aborted and a regular flush process carries on. `ALWAYS` is designed for user that need to reduce the number of L0 SST file created to a strict minimum, and can afford a small dent in performance (possibly hits to CPU usage, read efficiency, and maximum burst write throughput).
`ALTERNATE`: a flush is transformed into a `MemPurge` except if one of the memtables being flushed is the product of a previous `MemPurge`. `ALTERNATE` is a good tradeoff between reduction in number of L0 SST files created and performance. `ALTERNATE` perform particularly well for completely random garbage ratios, or garbage ratios anywhere in (0%,50%], and even higher when there is a wild variability in garbage ratios.
This PR also includes support for `experimental_mempurge_policy` in `db_bench`.
Testing was done locally by replacing all the `MemPurge` policies of the unit tests with `ALTERNATE`, as well as local testing with `db_crashtest.py` `whitebox` and `blackbox`. Overall, if an `ALWAYS` mempurge policy passes the tests, there is no reasons why an `ALTERNATE` policy would fail, and therefore the mempurge policy was set to `ALWAYS` for all mempurge unit tests.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8583
Reviewed By: pdillinger
Differential Revision: D29888050
Pulled By: bjlemaire
fbshipit-source-id: e2cf26646d66679f6f5fb29842624615610759c1
Summary:
PR https://github.com/facebook/rocksdb/issues/8519 fix db_bench_tool.cc for MSVC build errors by simply copy-paste, this PR fix the copy-paste while also works for MSVC.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8553
Reviewed By: ajkr
Differential Revision: D29838056
Pulled By: jay-zhuang
fbshipit-source-id: 0cd60c146b87a355c3dc1061dfe813169d75cea4
Summary:
Now we can analyze the MultiGet queries in the trace file and generate a set of the statistic and analysis files. Note that, when one MultiGet access N keys, we count each sub-get-query individually. But the over all query number is still the MultiGet not the sub-get-query.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8575
Test Plan: added new unit test and make check
Reviewed By: anand1976
Differential Revision: D29860633
Pulled By: zhichao-cao
fbshipit-source-id: a132128527f36828d266df8e36e3ec626c2170be
Summary:
Add flags `overwrite_probability` and `overwrite_window_size` flag to `db_bench`.
Add the possibility of performing a `filluniquerandom` benchmark with an overwrite probability.
For each write operation, there is a probability _p_ that the write is an overwrite (_p_=`overwrite_probability`).
When an overwrite is decided, the key is randomly chosen from the last _N_ keys previously inserted into the DB (with _N_=`overwrite_window_size`).
When a pure write is decided, the key inserted into the DB is unique and therefore will not be an overwrite.
The `overwrite_window_size` is used so that the user can decide if the overwrite are mostly targeting recently inserted keys (when `overwrite_window_size` is small compared to the total number of writes), or can also target keys inserted "a long time ago" (when `overwrite_window_size` is comparable to total number of writes).
Note that total number of writes = # of unique insertions + # of overwrites.
No unit test specifically added.
Local testing show the following **throughputs** for `filluniquerandom` with 1M total writes:
- bypass the code inserts (no `overwrite_probability` flag specified): ~14.0MB/s
- `overwrite_probability=0.99`, `overwrite_window_size=10`: ~17.0MB/s
- `overwrite_probability=0.10`, `overwrite_window_size=10`: ~14.0MB/s
- `overwrite_probability=0.99`, `overwrite_window_size=1M`: ~14.5MB/s
- `overwrite_probability=0.10`, `overwrite_window_size=1M`: ~14.0MB/s
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8569
Reviewed By: pdillinger
Differential Revision: D29818631
Pulled By: bjlemaire
fbshipit-source-id: d472b4ea4e457a4da7c4ee4f14b40cccd6a4587a
anand76