Summary:
Add PreReleaseCallback to be called at the end of WriteImpl but before publishing the sequence number. The callback is used in WritePrepareTxn to i) update the commit map, ii) update the last published sequence number in the 2nd write queue. It also ensures that all the commits will go to the 2nd queue.
These changes will ensure that the commit map is updated before the sequence number is published and used by reading snapshots. If we use two write queues, the snapshots will use the seq number published by the 2nd queue. If we use one write queue (the default, the snapshots will use the last seq number in the memtable, which also indicates the last published seq number.
Closes https://github.com/facebook/rocksdb/pull/3205
Differential Revision: D6438959
Pulled By: maysamyabandeh
fbshipit-source-id: f8b6c434e94bc5f5ab9cb696879d4c23e2577ab9
Summary:
Before we were checking every file in the level which was unnecessary. We can piggyback onto the code for checking point-key overlap, which already opens all the files that could possibly contain overlapping range deletions. This PR makes us check just the range deletions from those files, so no extra ones will be opened.
Closes https://github.com/facebook/rocksdb/pull/3179
Differential Revision: D6358125
Pulled By: ajkr
fbshipit-source-id: 00e200770fdb8f3cc6b1b2da232b755e4ba36279
Summary:
When snapshots are held for a long time, files may reach the bottom level containing overwritten/deleted keys. We previously had no mechanism to trigger compaction on such files. This particularly impacted DBs that write to different parts of the keyspace over time, as such files would never be naturally compacted due to second-last level files moving down. This PR introduces a mechanism for bottommost files to be recompacted upon releasing all snapshots that prevent them from dropping their deleted/overwritten keys.
- Changed `CompactionPicker` to compact files in `BottommostFilesMarkedForCompaction()`. These are the last choice when picking. Each file will be compacted alone and output to the same level in which it originated. The goal of this type of compaction is to rewrite the data excluding deleted/overwritten keys.
- Changed `ReleaseSnapshot()` to recompute the bottom files marked for compaction when the oldest existing snapshot changes, and schedule a compaction if needed. We cache the value that oldest existing snapshot needs to exceed in order for another file to be marked in `bottommost_files_mark_threshold_`, which allows us to avoid recomputing marked files for most snapshot releases.
- Changed `VersionStorageInfo` to track the list of bottommost files, which is recomputed every time the version changes by `UpdateBottommostFiles()`. The list of marked bottommost files is first computed in `ComputeBottommostFilesMarkedForCompaction()` when the version changes, but may also be recomputed when `ReleaseSnapshot()` is called.
- Extracted core logic of `Compaction::IsBottommostLevel()` into `VersionStorageInfo::RangeMightExistAfterSortedRun()` since logic to check whether a file is bottommost is now necessary outside of compaction.
Closes https://github.com/facebook/rocksdb/pull/3009
Differential Revision: D6062044
Pulled By: ajkr
fbshipit-source-id: 123d201cf140715a7d5928e8b3cb4f9cd9f7ad21
Summary:
The file numbers assigned post-repair were sometimes smaller than older files' numbers due to `LogAndApply` saving the wrong next file number in the manifest.
- Mark the highest file seen during repair as used before `LogAndApply` so the correct next file number will be stored.
- Renamed `MarkFileNumberUsedDuringRecovery` to `MarkFileNumberUsed` since now it's used during repair in addition to during recovery
- Added `TEST_Current_Next_FileNo` to expose the next file number for the unit test.
Closes https://github.com/facebook/rocksdb/pull/2988
Differential Revision: D6018083
Pulled By: ajkr
fbshipit-source-id: 3f25cbf74439cb8f16dd12af90b67f9f9f75e718
Summary:
Add kTypeBlobIndex value type, which will be used by blob db only, to insert a (key, blob_offset) KV pair. The purpose is to
1. Make it possible to open existing rocksdb instance as blob db. Existing value will be of kTypeIndex type, while value inserted by blob db will be of kTypeBlobIndex.
2. Make rocksdb able to detect if the db contains value written by blob db, if so return error.
3. Make it possible to have blob db optionally store value in SST file (with kTypeValue type) or as a blob value (with kTypeBlobIndex type).
The root db (DBImpl) basically pretended kTypeBlobIndex are normal value on write. On Get if is_blob is provided, return whether the value read is of kTypeBlobIndex type, or return Status::NotSupported() status if is_blob is not provided. On scan allow_blob flag is pass and if the flag is true, return wether the value is of kTypeBlobIndex type via iter->IsBlob().
Changes on blob db side will be in a separate patch.
Closes https://github.com/facebook/rocksdb/pull/2886
Differential Revision: D5838431
Pulled By: yiwu-arbug
fbshipit-source-id: 3c5306c62bc13bb11abc03422ec5cbcea1203cca
Summary:
This patch instruments the read path to verify each read value against an optional ReadCallback class. If the value is rejected, the reader moves on to the next value. The WritePreparedTxn makes use of this feature to skip sequence numbers that are not in the read snapshot.
Closes https://github.com/facebook/rocksdb/pull/2850
Differential Revision: D5787375
Pulled By: maysamyabandeh
fbshipit-source-id: 49d808b3062ab35e7ae98ad388f659757794184c
Summary:
When we had a single thread pool for compactions, a thread could be busy for a long time (minutes) executing a compaction involving the bottom level. In multi-instance setups, the entire thread pool could be consumed by such bottom-level compactions. Then, top-level compactions (e.g., a few L0 files) would be blocked for a long time ("head-of-line blocking"). Such top-level compactions are critical to prevent compaction stalls as they can quickly reduce number of L0 files / sorted runs.
This diff introduces a bottom-priority queue for universal compactions including the bottom level. This alleviates the head-of-line blocking situation for fast, top-level compactions.
- Added `Env::Priority::BOTTOM` thread pool. This feature is only enabled if user explicitly configures it to have a positive number of threads.
- Changed `ThreadPoolImpl`'s default thread limit from one to zero. This change is invisible to users as we call `IncBackgroundThreadsIfNeeded` on the low-pri/high-pri pools during `DB::Open` with values of at least one. It is necessary, though, for bottom-pri to start with zero threads so the feature is disabled by default.
- Separated `ManualCompaction` into two parts in `PrepickedCompaction`. `PrepickedCompaction` is used for any compaction that's picked outside of its execution thread, either manual or automatic.
- Forward universal compactions involving last level to the bottom pool (worker thread's entry point is `BGWorkBottomCompaction`).
- Track `bg_bottom_compaction_scheduled_` so we can wait for bottom-level compactions to finish. We don't count them against the background jobs limits. So users of this feature will get an extra compaction for free.
Closes https://github.com/facebook/rocksdb/pull/2580
Differential Revision: D5422916
Pulled By: ajkr
fbshipit-source-id: a74bd11f1ea4933df3739b16808bb21fcd512333
Summary:
This reverts the previous commit 1d7048c598, which broke the build.
Did a `git revert 1d7048c`.
Closes https://github.com/facebook/rocksdb/pull/2627
Differential Revision: D5476473
Pulled By: sagar0
fbshipit-source-id: 4756ff5c0dfc88c17eceb00e02c36176de728d06
Summary: This uses `clang-tidy` to comment out unused parameters (in functions, methods and lambdas) in fbcode. Cases that the tool failed to handle are fixed manually.
Reviewed By: igorsugak
Differential Revision: D5454343
fbshipit-source-id: 5dee339b4334e25e963891b519a5aa81fbf627b2
Summary:
Throughput: 46k tps in our sysbench settings (filling the details later)
The idea is to have the simplest change that gives us a reasonable boost
in 2PC throughput.
Major design changes:
1. The WAL file internal buffer is not flushed after each write. Instead
it is flushed before critical operations (WAL copy via fs) or when
FlushWAL is called by MySQL. Flushing the WAL buffer is also protected
via mutex_.
2. Use two sequence numbers: last seq, and last seq for write. Last seq
is the last visible sequence number for reads. Last seq for write is the
next sequence number that should be used to write to WAL/memtable. This
allows to have a memtable write be in parallel to WAL writes.
3. BatchGroup is not used for writes. This means that we can have
parallel writers which changes a major assumption in the code base. To
accommodate for that i) allow only 1 WriteImpl that intends to write to
memtable via mem_mutex_--which is fine since in 2PC almost all of the memtable writes
come via group commit phase which is serial anyway, ii) make all the
parts in the code base that assumed to be the only writer (via
EnterUnbatched) to also acquire mem_mutex_, iii) stat updates are
protected via a stat_mutex_.
Note: the first commit has the approach figured out but is not clean.
Submitting the PR anyway to get the early feedback on the approach. If
we are ok with the approach I will go ahead with this updates:
0) Rebase with Yi's pipelining changes
1) Currently batching is disabled by default to make sure that it will be
consistent with all unit tests. Will make this optional via a config.
2) A couple of unit tests are disabled. They need to be updated with the
serial commit of 2PC taken into account.
3) Replacing BatchGroup with mem_mutex_ got a bit ugly as it requires
releasing mutex_ beforehand (the same way EnterUnbatched does). This
needs to be cleaned up.
Closes https://github.com/facebook/rocksdb/pull/2345
Differential Revision: D5210732
Pulled By: maysamyabandeh
fbshipit-source-id: 78653bd95a35cd1e831e555e0e57bdfd695355a4
Summary:
We estimate number of reads per SST files, by updating the counter per file in sampled read requests. This information can later be used to trigger compactions to improve read performacne.
Closes https://github.com/facebook/rocksdb/pull/2417
Differential Revision: D5193528
Pulled By: siying
fbshipit-source-id: b4241c5ad0eaf444b61afb53f8e6290d9f5da2df
Summary:
The range deletion meta-block iterators weren't getting cleaned up properly since they don't support arena allocation. I didn't implement arena support since, in the general case, each iterator is used only once and separately from all other iterators, so there should be no benefit to data locality.
Anyways, this diff fixes up #2370 by treating range deletion iterators as non-arena-allocated.
Closes https://github.com/facebook/rocksdb/pull/2399
Differential Revision: D5171119
Pulled By: ajkr
fbshipit-source-id: bef6f5c4c5905a124f4993945aed4bd86e2807d8
Summary:
Previously we returned NotSupported when ingesting files into a database containing any range deletions. This diff adds the support.
- Flush if any memtable contains range deletions overlapping the to-be-ingested file
- Place to-be-ingested file before any level that contains range deletions overlapping it.
- Added support for `Version` to return iterators over range deletions in a given level. Previously, we piggybacked getting range deletions onto `Version`'s `Get()` / `AddIterator()` functions by passing them a `RangeDelAggregator*`. But file ingestion needs to get iterators over range deletions, not populate an aggregator (since the aggregator does collapsing and doesn't expose the actual ranges).
Closes https://github.com/facebook/rocksdb/pull/2370
Differential Revision: D5127648
Pulled By: ajkr
fbshipit-source-id: 816faeb9708adfa5287962bafdde717db56e3f1a
Summary:
Move some files under util/ to new directories env/, monitoring/ options/ and cache/
Closes https://github.com/facebook/rocksdb/pull/2090
Differential Revision: D4833681
Pulled By: siying
fbshipit-source-id: 2fd8bef
Summary:
PinnableSlice
Summary:
Currently the point lookup values are copied to a string provided by the
user. This incures an extra memcpy cost. This patch allows doing point lookup
via a PinnableSlice which pins the source memory location (instead of
copying their content) and releases them after the content is consumed
by the user. The old API of Get(string) is translated to the new API
underneath.
Here is the summary for improvements:
value 100 byte: 1.8% regular, 1.2% merge values
value 1k byte: 11.5% regular, 7.5% merge values
value 10k byte: 26% regular, 29.9% merge values
The improvement for merge could be more if we extend this approach to
pin the merge output and delay the full merge operation until the user
actually needs it. We have put that for future work.
PS:
Sometimes we observe a small decrease in performance when switching from
t5452014 to this patch but with the old Get(string) API. The d
Closes https://github.com/facebook/rocksdb/pull/1756
Differential Revision: D4391738
Pulled By: maysamyabandeh
fbshipit-source-id: 6f3edd3
Summary:
reimplement the compaction expansion on lower level.
Considering such a case:
input level file: 1[B E] 2[F G] 3[H I] 4 [J M]
output level file: 5[A C] 6[D K] 7[L O]
If we initially pick file 2, now we will compact file 2 and 6. But we can safely compact 2, 3 and 6 without expanding the output level.
The previous code is messy and wrong.
In this diff, I first determine the input range [a, b], and output range [c, d],
then we get the range [e,f] = [min(a, c), max(b, d] and put all eligible clean-cut files within [e, f] into this compaction.
**Note: clean-cut means the files don't have the same user key on the boundaries of some files that are not chosen in this compaction**.
Closes https://github.com/facebook/rocksdb/pull/1760
Differential Revision: D4395564
Pulled By: lightmark
fbshipit-source-id: 2dc2c5c
Summary:
Fix the bug when sync log fail, FlushJob::Run() will not be execute and
reference to cfd->current() will not be release.
Closes https://github.com/facebook/rocksdb/pull/1792
Differential Revision: D4441316
Pulled By: yiwu-arbug
fbshipit-source-id: 5523e28
Summary:
Currently the point lookup values are copied to a string provided by the user.
This incures an extra memcpy cost. This patch allows doing point lookup
via a PinnableSlice which pins the source memory location (instead of
copying their content) and releases them after the content is consumed
by the user. The old API of Get(string) is translated to the new API
underneath.
Here is the summary for improvements:
1. value 100 byte: 1.8% regular, 1.2% merge values
2. value 1k byte: 11.5% regular, 7.5% merge values
3. value 10k byte: 26% regular, 29.9% merge values
The improvement for merge could be more if we extend this approach to
pin the merge output and delay the full merge operation until the user
actually needs it. We have put that for future work.
PS:
Sometimes we observe a small decrease in performance when switching from
t5452014 to this patch but with the old Get(string) API. The difference
is a little and could be noise. More importantly it is safely
cancelled
Closes https://github.com/facebook/rocksdb/pull/1732
Differential Revision: D4374613
Pulled By: maysamyabandeh
fbshipit-source-id: a077f1a
Summary:
Note: reviewed in https://reviews.facebook.net/D65115
- DBIter maintains a range tombstone accumulator. We don't cleanup obsolete tombstones yet, so if the user seeks back and forth, the same tombstones would be added to the accumulator multiple times.
- DBImpl::NewInternalIterator() (used to make DBIter's underlying iterator) adds memtable/L0 range tombstones, L1+ range tombstones are added on-demand during NewSecondaryIterator() (see D62205)
- DBIter uses ShouldDelete() when advancing to check whether keys are covered by range tombstones
Closes https://github.com/facebook/rocksdb/pull/1464
Differential Revision: D4131753
Pulled By: ajkr
fbshipit-source-id: be86559
Summary:
During Get()/MultiGet(), build up a RangeDelAggregator with range
tombstones as we search through live memtable, immutable memtables, and
SST files. This aggregator is then used by memtable.cc's SaveValue() and
GetContext::SaveValue() to check whether keys are covered.
added tests for Get on memtables/files; end-to-end tests mainly in https://reviews.facebook.net/D64761
Closes https://github.com/facebook/rocksdb/pull/1456
Differential Revision: D4111271
Pulled By: ajkr
fbshipit-source-id: 6e388d4
Summary:
Changes in the diff
API changes:
- Introduce IngestExternalFile to replace AddFile (I think this make the API more clear)
- Introduce IngestExternalFileOptions (This struct will encapsulate the options for ingesting the external file)
- Deprecate AddFile() API
Logic changes:
- If our file overlap with the memtable we will flush the memtable
- We will find the first level in the LSM tree that our file key range overlap with the keys in it
- We will find the lowest level in the LSM tree above the the level we found in step 2 that our file can fit in and ingest our file in it
- We will assign a global sequence number to our new file
- Remove AddFile restrictions by using global sequence numbers
Other changes:
- Refactor all AddFile logic to be encapsulated in ExternalSstFileIngestionJob
Test Plan:
unit tests (still need to add more)
addfile_stress (https://reviews.facebook.net/D65037)
Reviewers: yiwu, andrewkr, lightmark, yhchiang, sdong
Reviewed By: sdong
Subscribers: jkedgar, hcz, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D65061
Summary:
This diff introduces RangeDelAggregator, which takes ownership of iterators
provided to it via AddTombstones(). The tombstones are organized in a two-level
map (snapshot stripe -> begin key -> tombstone). Tombstone creation avoids data
copy by holding Slices returned by the iterator, which remain valid thanks to pinning.
For compaction, we create a hierarchical range tombstone iterator with structure
matching the iterator over compaction input data. An aggregator based on that
iterator is used by CompactionIterator to determine which keys are covered by
range tombstones. In case of merge operand, the same aggregator is used by
MergeHelper. Upon finishing each file in the compaction, relevant range tombstones
are added to the output file's range tombstone metablock and file boundaries are
updated accordingly.
To check whether a key is covered by range tombstone, RangeDelAggregator::ShouldDelete()
considers tombstones in the key's snapshot stripe. When this function is used outside of
compaction, it also checks newer stripes, which can contain covering tombstones. Currently
the intra-stripe check involves a linear scan; however, in the future we plan to collapse ranges
within a stripe such that binary search can be used.
RangeDelAggregator::AddToBuilder() adds all range tombstones in the table's key-range
to a new table's range tombstone meta-block. Since range tombstones may fall in the gap
between files, we may need to extend some files' key-ranges. The strategy is (1) first file
extends as far left as possible and other files do not extend left, (2) all files extend right
until either the start of the next file or the end of the last range tombstone in the gap,
whichever comes first.
One other notable change is adding release/move semantics to ScopedArenaIterator
such that it can be used to transfer ownership of an arena-allocated iterator, similar to
how unique_ptr is used for malloc'd data.
Depends on D61473
Test Plan: compaction_iterator_test, mock_table, end-to-end tests in D63927
Reviewers: sdong, IslamAbdelRahman, wanning, yhchiang, lightmark
Reviewed By: lightmark
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D62205
Summary:
We always run consistency checks when compiling in debug mode
allow users to set Options::force_consistency_checks to true to be able to run such checks even when compiling in release mode
Test Plan:
make check -j64
make release
Reviewers: lightmark, sdong, yiwu
Reviewed By: yiwu
Subscribers: hermanlee4, andrewkr, yoshinorim, jkedgar, dhruba
Differential Revision: https://reviews.facebook.net/D64701
Summary: Use ImmutableDBOptions/MutableDBOptions internally and DBOptions only for user-facing APIs. MutableDBOptions is barely a placeholder for now. I'll start to move options to MutableDBOptions in following diffs.
Test Plan:
make all check
Reviewers: yhchiang, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D64065
Summary:
* Change constructor of MutableCFOptions to depends only on ColumnFamilyOptions.
* Move `max_subcompactions`, `compaction_options_fifo` and `compaction_pri` to ImmutableCFOptions to make it clear that they are immutable.
Test Plan: existing unit tests.
Reviewers: yhchiang, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D63945
Summary: Add option write_buffer_manager to help users control total memory spent on memtables across multiple DB instances.
Test Plan: Add a new unit test.
Reviewers: yhchiang, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: adela, benj, sumeet, muthu, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D59925
Summary:
memtable_prefix_bloom_probes is not a critical option. Remove it to reduce number of options.
It's easier for users to make mistakes with memtable_prefix_bloom_bits, turn it to memtable_prefix_bloom_bits_ratio
Test Plan: Run all existing tests
Reviewers: yhchiang, igor, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: gunnarku, yoshinorim, MarkCallaghan, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D59199
Summary: Backup options file to private directory
Test Plan:
backupable_db_test.cc, BackupOptions
Modify DB options by calling OpenDB for 3 times. Check the latest options file is in the right place. Also check no redundent files are backuped.
Reviewers: andrewkr
Reviewed By: andrewkr
Subscribers: leveldb, dhruba, andrewkr
Differential Revision: https://reviews.facebook.net/D59373
Summary: Make CompactionOptionsFIFO a part of mutable_cf_options
Test Plan: UT
Reviewers: sdong
Reviewed By: sdong
Subscribers: andrewkr, lgalanis, dhruba
Differential Revision: https://reviews.facebook.net/D58653
Summary:
This is needed so we can measure compression ratio improvements
achieved by D52287.
The property compares raw data size against the total file size for a given
level. If the level is empty it should return 0.0.
Test Plan: new unit test
Reviewers: IslamAbdelRahman, yhchiang, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D56967
Summary:
When subcompaction is used, all subcompactions share the same Compaction
pointer in CompactionJob while each subcompaction all keeps their mutable
stats in SubcompactionState. However, there're still some mutable part
that is currently store in the shared Compaction pointer.
This patch makes two changes:
1. Make the shared Compaction pointer const so that it can never be modified
during the compaction.
2. Move necessary states from Compaction to SubcompactionState.
3. Make functions of Compaction const if the function does not modify
its internal state.
Test Plan: rocksdb and MyRocks test
Reviewers: sdong, kradhakrishnan, andrewkr, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: andrewkr, dhruba, yoshinorim, gunnarku, leveldb
Differential Revision: https://reviews.facebook.net/D55923
Summary:
- Keep track of obsolete manifests in VersionSet
- Updated FindObsoleteFiles() to put obsolete manifests in the JobContext for later use by PurgeObsoleteFiles()
- Added test case that verifies a stale manifest is deleted by a non-full purge
Test Plan:
$ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation
Reviewers: IslamAbdelRahman, yoshinorim, sdong
Reviewed By: sdong
Subscribers: andrewkr, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D55269
Summary:
Following up on D53493, we can still enable the filter-skipping
optimization for last file in L0. It's correct to assume the key will be present
in the last L0 file when we're hit-optimized and L0 is deepest.
The FilePicker encapsulates the state for traversing each level's files, so I
needed to make it expose whether the returned file is last in its level.
Test Plan:
verified below test fails before this patch and passes afterwards.
The change to how the test memtable is populated is needed so file 1 has keys
(0, 30, 60), file 2 has keys (10, 40, 70), etc.
$ ./db_universal_compaction_test --gtest_filter=UniversalCompactionNumLevels/DBTestUniversalCompaction.OptimizeFiltersForHits/*
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D53583
Summary: Revert the functionaility of D7809 (but I'm keeping the logging and test code). We decided it was dangerous to ignore sync failures based on attempting to read the data written. The read does not tell us whether the data was synced.
Test Plan: There was no test for the particular functionaility that was reverted. Keeping the test code from D7809 that tests whether we set the DB to be readonly when paranoid checks are enabled.
Reviewers: rven, yhchiang, kradhakrishnan, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D52989
Summary: It's usually hard for users to set a value of options.delayed_write_rate. With this diff, after slowdown condition triggers, we greedily reduce write rate if estimated pending compaction bytes increase. If estimated compaction pending bytes drop, we increase the write rate.
Test Plan:
Add a unit test
Test with db_bench setting:
TEST_TMPDIR=/dev/shm/ ./db_bench --benchmarks=fillrandom -num=10000000 --soft_pending_compaction_bytes_limit=1000000000 --hard_pending_compaction_bytes_limit=3000000000 --delayed_write_rate=100000000
and make sure without the commit, write stop will happen, but with the commit, it will not happen.
Reviewers: igor, anthony, rven, yhchiang, kradhakrishnan, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D52131
Summary:
When Get() or NewIterator() trigger file loads, skip caching the filter block if
(1) optimize_filters_for_hits is set and (2) the file is on the bottommost
level. Also skip checking filters under the same conditions, which means that
for a preloaded file or a file that was trivially-moved to the bottom level, its
filter block will eventually expire from the cache.
- added parameters/instance variables in various places in order to propagate the config ("skip_filters") from version_set to block_based_table_reader
- in BlockBasedTable::Rep, this optimization prevents filter from being loaded when the file is opened simply by setting filter_policy = nullptr
- in BlockBasedTable::Get/BlockBasedTable::NewIterator, this optimization prevents filter from being used (even if it was loaded already) by setting filter = nullptr
Test Plan:
updated unit test:
$ ./db_test --gtest_filter=DBTest.OptimizeFiltersForHits
will also run 'make check'
Reviewers: sdong, igor, paultuckfield, anthony, rven, kradhakrishnan, IslamAbdelRahman, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D51633
Summary:
Currently, transactions can fail even if there is no actual write conflict. This is due to relying on only the memtables to check for write-conflicts. Users have to tune memtable settings to try to avoid this, but it's hard to figure out exactly how to tune these settings.
With this diff, TransactionDB will use both memtables and SST files to determine if there are any write conflicts. This relies on the fact that BlockBasedTable stores sequence numbers for all writes that happen after any open snapshot. Also, D50295 is needed to prevent SingleDelete from disappearing writes (the TODOs in this test code will be fixed once the other diff is approved and merged).
Note that Optimistic transactions will still rely on tuning memtable settings as we do not want to read from SST while on the write thread. Also, memtable settings can still be used to reduce how often TransactionDB needs to read SST files.
Test Plan: unit tests, db bench
Reviewers: rven, yhchiang, kradhakrishnan, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb, yoshinorim
Differential Revision: https://reviews.facebook.net/D50475
Summary: Deprecate options.soft_rate_limit, which is hard to tune, with options.soft_pending_compaction_bytes_limit, which would trigger the slowdown if estimated pending compaction bytes exceeds the threshold. The hope is to make it more striaght-forward to tune.
Test Plan: Modify DBTest.SoftLimit to cover options.soft_pending_compaction_bytes_limit instead; run all unit tests.
Reviewers: IslamAbdelRahman, yhchiang, rven, kradhakrishnan, igor, anthony
Reviewed By: anthony
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D51117
Summary: crash_test sometimes fails, hitting the add file overlapping assert. Add information in info logs help us to find the bug.
Test Plan: Run all test suites. Do some manual tests to make sure printing is correct.
Reviewers: kradhakrishnan, yhchiang, anthony, IslamAbdelRahman, rven, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D49017
Igor Sugak