Summary:
We started getting two kinds of crashes since we started using `DB::CompactFiles()`:
(1) `CompactFiles()` fails saying something like "/data/logdevice/4440/shard12/012302.sst: No such file or directory", and presumably makes DB read-only,
(2) DB fails to open saying "Corruption: Can't access /267000.sst: IO error: /data/logdevice/4440/shard1/267000.sst: No such file or directory".
AFAICT, both can be explained by background thread deleting compaction output as "obsolete" while it's being written, before it's committed to manifest. If it ends up committed to the manifest, we get (2); if compaction notices the disappearance and fails, we get (1). The internal tasks t10068021 and t10134177 have some details about the investigation that led to this.
Test Plan: `make -j check`; the new test fails to reopen the DB without the fix
Reviewers: yhchiang
Reviewed By: yhchiang
Subscribers: dhruba, sdong
Differential Revision: https://reviews.facebook.net/D54561
Summary:
Introude SstFileManager::SetMaxAllowedSpaceUsage() that can be used to limit the maximum space usage allowed for RocksDB.
When this limit is exceeded WriteImpl() will fail and return Status::Aborted()
Test Plan: unit testing
Reviewers: yhchiang, anthony, andrewkr, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D53763
Summary: There is an issue in DBImpl::WriteImpl where if an empty writebatch comes in and sync=true then the logs will be marked as being synced yet the sync never actually happens because there is no data in the writebatch. This causes the next incoming batch to hang while waiting for the logs to complete syncing. This fix syncs logs even if the writebatch is empty.
Test Plan: DoubleEmptyBatch unit test in transaction_test.
Reviewers: yoshinorim, hermanlee4, sdong, ngbronson, anthony
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D54057
Summary:
Add kSstFileTier to ReadTier, which allows Get and MultiGet to
read only directly from SST files and skip mem-tables.
kSstFileTier = 0x2 // data in SST files.
// Note that this ReadTier currently only supports
// Get and MultiGet and does not support iterators.
Test Plan: add new test in db_test.
Reviewers: anthony, IslamAbdelRahman, rven, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: igor, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D53511
Summary:
copy from task 8196669:
1) Optimistic transactions do not support batching writes from different threads.
2) Pessimistic transactions do not support batching writes if an expiration time is set.
In these 2 cases, we currently do not do any write batching in DBImpl::WriteImpl() because there is a WriteCallback that could decide at the last minute to abort the write. But we could support batching write operations with callbacks if we make sure to process the callbacks correctly.
To do this, we would first need to modify write_thread.cc to stop preventing writes with callbacks from being batched together. Then we would need to change DBImpl::WriteImpl() to call all WriteCallback's in a batch, only write the batches that succeed, and correctly set the state of each batch's WriteThread::Writer.
Test Plan: Added test WriteWithCallbackTest to write_callback_test.cc which creates multiple client threads and verifies that writes are batched and executed properly.
Reviewers: hermanlee4, anthony, ngbronson
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D52863
Summary:
Before this diff, there were duplicated constants to refer to properties (user-
facing API had strings and InternalStats had an enum). I noticed these were
inconsistent in terms of which constants are provided, names of constants, and
documentation of constants. Overall it seemed annoying/error-prone to maintain
these duplicated constants.
So, this diff gets rid of InternalStats's constants and replaces them with a map
keyed on the user-facing constant. The value in that map contains a function
pointer to get the property value, so we don't need to do string matching while
holding db->mutex_. This approach has a side benefit of making many small
handler functions rather than a giant switch-statement.
Test Plan: db_properties_test passes, running "make commit-prereq -j32"
Reviewers: sdong, yhchiang, kradhakrishnan, IslamAbdelRahman, rven, anthony
Reviewed By: anthony
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D53253
Summary:
Concurrent memtable adds were incorrectly computing
the last sequence number for a write batch group when the
write batches were not solitary. This is the cause of
https://github.com/facebook/mysql-5.6/issues/155
Test Plan:
1. unit tests
2. new unit test
3. parallel db_bench stress tests with batch size of 10 and asserts enabled
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: IslamAbdelRahman, MarkCallaghan, dhruba
Differential Revision: https://reviews.facebook.net/D53595
Summary:
If options.base_background_compactions is given, we try to schedule number of compactions not existing this number, only when L0 files increase to certain number, or pending compaction bytes more than certain threshold, we schedule compactions based on options.max_background_compactions.
The watermarks are calculated based on slowdown thresholds.
Test Plan:
Add new test cases in column_family_test.
Adding more unit tests.
Reviewers: IslamAbdelRahman, yhchiang, kradhakrishnan, rven, anthony
Reviewed By: anthony
Subscribers: leveldb, dhruba, yoshinorim
Differential Revision: https://reviews.facebook.net/D53409
Summary:
Add a new class SstFileTracker that will be notified whenever a DB add/delete/move and sst file, it will also replace DeleteScheduler
SstFileTracker can be used later to abort writes when we exceed a specific size
Test Plan: unit tests
Reviewers: rven, anthony, yhchiang, sdong
Reviewed By: sdong
Subscribers: igor, lovro, march, dhruba
Differential Revision: https://reviews.facebook.net/D50469
Summary:
We can avoid the dependency by forward-declaring ColumnFamilyData and
then treating it as a black box. That means callers of ThreadStatusUtil need to
explicitly provide more options, even if they can be derived from the
ColumnFamilyData, since ThreadStatusUtil doesn't include the definition.
This is part of a series of diffs to eliminate circular dependencies between
directories (e.g., db/* files depending on util/* files and vice-versa).
Test Plan:
$ ./db_test --gtest_filter=DBTest.GetThreadStatus
$ make -j32 commit-prereq
Reviewers: sdong, yhchiang, IslamAbdelRahman
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D53361
Summary:
I split the db-specific test points out into a separate file under db/
directory. There were also a few bugs to fix in xfunc.{h,cc} that prevented it
from compiling previously; see https://reviews.facebook.net/D36825.
Test Plan:
compilation works now, below command works, will also run "make xfunc".
$ make check ROCKSDB_XFUNC_TEST='managed_new' tests-regexp='DBTest' -j32
Reviewers: sdong, yhchiang
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D53343
Summary:
SstFileWriter may create an sst file with no entries
Right now this will fail when being ingested using DB::AddFile() saying that the keys are corrupted
Test Plan: make check
Reviewers: yhchiang, rven, anthony, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D52815
Makefile adjust paths for solaris build
Makefile enable _GLIBCXX_USE_C99 so that std::to_string is available
db_compaction_test.cc Initialise a variable to avoid a compilation error
db_impl.cc Include <alloca.h>
db_test.cc Include <alloca.h>
Environment.java recognise solaris envrionment
options_bulder.cc Make log unambiguous
geodb_impl.cc Make log and floor unambiguous
Summary:
While running the myrocks regression suite, I found that while
dropping a table soon after inserting rows into it resulted in an
assertion failure in CheckConsistencyForDeletes for not finding
a file which was recently added or moved. Marking the files to be
deleted as being compacted before calling LogAndApplyChange
fixed the assertion failures.
Test Plan: DBCompactionTest.DeleteFileRange
Reviewers: IslamAbdelRahman, anthony, yhchiang, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: dhruba, yoshinorim, leveldb
Differential Revision: https://reviews.facebook.net/D52599
Summary: DBImpl::GetLatestSequenceForKey() can do memcpy's to load a value that will never be used. This can be optimized by changing all the Get() functions called to optionally not fetch the value (and only fetch the sequencenumber).
Test Plan: optimistic_transaction_test and transaction_test
Reviewers: anthony
Reviewed By: anthony
Subscribers: leveldb, dhruba, hermanlee4
Differential Revision: https://reviews.facebook.net/D52227
Summary:
We need to clean the job context if we end up not deleting any
files because no files are in the range specified.
Test Plan: DBCompactionTest.DeleteFileRange
Reviewers: sdong, anthony, yhchiang, kradhakrishnan, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D52467
Summary:
myrocks seems to build rocksdb using
-Wmissing-field-initializers (and treats warnings as errors). This diff
adds that flag to the rocksdb build, and fixes the compilation failures
that result. I have not checked for any other differences in the build
flags for rocksdb build as part of myrocks.
Test Plan: make check
Reviewers: sdong, rven
Reviewed By: rven
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D52443
Summary:
This is an initial diff for providing the ability to delete
files which are completely within a given range of keys.
Test Plan: DBCompactionTest.DeleteRange
Reviewers: IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: yoshinorim, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D52293
Summary: Fix some CLANG errors introduced in 7d87f02799
Test Plan: Build with both of CLANG and gcc
Reviewers: rven, yhchiang, kradhakrishnan, anthony, IslamAbdelRahman, ngbronson
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D52329
Summary:
This diff adds support for concurrent adds to the skiplist memtable
implementations. Memory allocation is made thread-safe by the addition of
a spinlock, with small per-core buffers to avoid contention. Concurrent
memtable writes are made via an additional method and don't impose a
performance overhead on the non-concurrent case, so parallelism can be
selected on a per-batch basis.
Write thread synchronization is an increasing bottleneck for higher levels
of concurrency, so this diff adds --enable_write_thread_adaptive_yield
(default off). This feature causes threads joining a write batch
group to spin for a short time (default 100 usec) using sched_yield,
rather than going to sleep on a mutex. If the timing of the yield calls
indicates that another thread has actually run during the yield then
spinning is avoided. This option improves performance for concurrent
situations even without parallel adds, although it has the potential to
increase CPU usage (and the heuristic adaptation is not yet mature).
Parallel writes are not currently compatible with
inplace updates, update callbacks, or delete filtering.
Enable it with --allow_concurrent_memtable_write (and
--enable_write_thread_adaptive_yield). Parallel memtable writes
are performance neutral when there is no actual parallelism, and in
my experiments (SSD server-class Linux and varying contention and key
sizes for fillrandom) they are always a performance win when there is
more than one thread.
Statistics are updated earlier in the write path, dropping the number
of DB mutex acquisitions from 2 to 1 for almost all cases.
This diff was motivated and inspired by Yahoo's cLSM work. It is more
conservative than cLSM: RocksDB's write batch group leader role is
preserved (along with all of the existing flush and write throttling
logic) and concurrent writers are blocked until all memtable insertions
have completed and the sequence number has been advanced, to preserve
linearizability.
My test config is "db_bench -benchmarks=fillrandom -threads=$T
-batch_size=1 -memtablerep=skip_list -value_size=100 --num=1000000/$T
-level0_slowdown_writes_trigger=9999 -level0_stop_writes_trigger=9999
-disable_auto_compactions --max_write_buffer_number=8
-max_background_flushes=8 --disable_wal --write_buffer_size=160000000
--block_size=16384 --allow_concurrent_memtable_write" on a two-socket
Xeon E5-2660 @ 2.2Ghz with lots of memory and an SSD hard drive. With 1
thread I get ~440Kops/sec. Peak performance for 1 socket (numactl
-N1) is slightly more than 1Mops/sec, at 16 threads. Peak performance
across both sockets happens at 30 threads, and is ~900Kops/sec, although
with fewer threads there is less performance loss when the system has
background work.
Test Plan:
1. concurrent stress tests for InlineSkipList and DynamicBloom
2. make clean; make check
3. make clean; DISABLE_JEMALLOC=1 make valgrind_check; valgrind db_bench
4. make clean; COMPILE_WITH_TSAN=1 make all check; db_bench
5. make clean; COMPILE_WITH_ASAN=1 make all check; db_bench
6. make clean; OPT=-DROCKSDB_LITE make check
7. verify no perf regressions when disabled
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, IslamAbdelRahman, anthony, yhchiang, rven, sdong, guyg8, kradhakrishnan, dhruba
Differential Revision: https://reviews.facebook.net/D50589
Summary:
Add CompactionReason to CompactionJobInfo
This will allow users to understand why compaction started which will help options tuning
Test Plan:
added new tests
make check -j64
Reviewers: yhchiang, anthony, kradhakrishnan, sdong, rven
Reviewed By: rven
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D51975
Summary:
This patch fixes https://github.com/facebook/mysql-5.6/issues/121
There is a recent change in rocksdb to disable auto compactions on startup: https://reviews.facebook.net/D51147. However, there is a small timing window where a column family needs to be compacted and schedules a compaction, but the scheduled compaction fails when it checks the disable_auto_compactions setting. The expectation is once the application is ready, it will call EnableAutoCompactions() to allow new compactions to go through. However, if the Column family is stalled because L0 is full, and no writes can go through, it is possible the column family may never have a new compaction request get scheduled. EnableAutoCompaction() should probably schedule an new flush and compaction event when it resets disable_auto_compaction.
Using InstallSuperVersionAndScheduleWork, we call SchedulePendingFlush,
SchedulePendingCompaction, as well as MaybeScheduleFlushOrcompaction on all the
column families to avoid the situation above.
This is still a first pass for feedback.
Could also just call SchedePendingFlush and SchedulePendingCompaction directly.
Test Plan:
Run on Asan build
cd _build-5.6-ASan/ && ./mysql-test/mtr --mem --big --testcase-timeout=36000 --suite-timeout=12000 --parallel=16 --suite=rocksdb,rocksdb_rpl,rocksdb_sys_vars --mysqld=--default-storage-engine=rocksdb --mysqld=--skip-innodb --mysqld=--default-tmp-storage-engine=MyISAM --mysqld=--rocksdb rocksdb_rpl.rpl_rocksdb_stress_crash --repeat=1000
Ensure that it no longer hangs during the test.
Reviewers: hermanlee4, yhchiang, anthony
Reviewed By: anthony
Subscribers: leveldb, yhchiang, dhruba
Differential Revision: https://reviews.facebook.net/D51747
Summary:
When there are waiting manual compactions, we need to signal
them after removing the current manual compaction from the deque.
Test Plan: ColumnFamilytTest.SameCFManualManualCommaction
Reviewers: anthony, IslamAbdelRahman, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: dhruba, yoshinorim
Differential Revision: https://reviews.facebook.net/D52119
Summary:
This patch update the Iterator API to introduce new functions that allow users to keep the Slices returned by key() valid as long as the Iterator is not deleted
ReadOptions::pin_data : If true keep loaded blocks in memory as long as the iterator is not deleted
Iterator::IsKeyPinned() : If true, this mean that the Slice returned by key() is valid as long as the iterator is not deleted
Also add a new option BlockBasedTableOptions::use_delta_encoding to allow users to disable delta_encoding if needed.
Benchmark results (using https://phabricator.fb.com/P20083553)
```
// $ du -h /home/tec/local/normal.4K.Snappy/db10077
// 6.1G /home/tec/local/normal.4K.Snappy/db10077
// $ du -h /home/tec/local/zero.8K.LZ4/db10077
// 6.4G /home/tec/local/zero.8K.LZ4/db10077
// Benchmarks for shard db10077
// _build/opt/rocks/benchmark/rocks_copy_benchmark \
// --normal_db_path="/home/tec/local/normal.4K.Snappy/db10077" \
// --zero_db_path="/home/tec/local/zero.8K.LZ4/db10077"
// First run
// ============================================================================
// rocks/benchmark/RocksCopyBenchmark.cpp relative time/iter iters/s
// ============================================================================
// BM_StringCopy 1.73s 576.97m
// BM_StringPiece 103.74% 1.67s 598.55m
// ============================================================================
// Match rate : 1000000 / 1000000
// Second run
// ============================================================================
// rocks/benchmark/RocksCopyBenchmark.cpp relative time/iter iters/s
// ============================================================================
// BM_StringCopy 611.99ms 1.63
// BM_StringPiece 203.76% 300.35ms 3.33
// ============================================================================
// Match rate : 1000000 / 1000000
```
Test Plan: Unit tests
Reviewers: sdong, igor, anthony, yhchiang, rven
Reviewed By: rven
Subscribers: dhruba, lovro, adsharma
Differential Revision: https://reviews.facebook.net/D48999
Summary:
List of changes:
1) Fix the snprintf() usage in cases where wrong variable was used to determine the output buffer size.
2) Remove unnecessary checks before calling delete operator.
3) Increase code correctness by using size_t type when getting vector's size.
4) Unify the coding style by removing namespace::std usage at the top of the file to confirm to the majority usage.
5) Fix various lint errors pointed out by 'arc lint'.
Test Plan:
Code review and build:
git diff
make clean
make -j 32 commit-prereq
arc lint
Reviewers: kradhakrishnan, sdong, rven, anthony, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D51849
Summary:
This diff provides a framework for doing manual
compactions in parallel with other compactions. We now have a deque of manual compactions. We also pass manual compactions as an argument from RunManualCompactions down to
BackgroundCompactions, so that RunManualCompactions can be reentrant.
Parallelism is controlled by the two routines
ConflictingManualCompaction to allow/disallow new parallel/manual
compactions based on already existing ManualCompactions. In this diff, by default manual compactions still have to run exclusive of other compactions. However, by setting the compaction option, exclusive_manual_compaction to false, it is possible to run other compactions in parallel with a manual compaction. However, we are still restricted to one manual compaction per column family at a time. All of these restrictions will be relaxed in future diffs.
I will be adding more tests later.
Test Plan: Rocksdb regression + new tests + valgrind
Reviewers: igor, anthony, IslamAbdelRahman, kradhakrishnan, yhchiang, sdong
Reviewed By: sdong
Subscribers: yoshinorim, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D47973
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: For Transactions, we want to start using the SST files to do write conflict checking. To do this, we need to make sure that compaction never removes all writes if an earlier snapshot exists. So I had to change the way we process SingleDeletes to sometimes leave a SingleDelete behind when we encounter a Put followed by a SingleDelete. See the comments in this diff for a more detailed explanation.
Test Plan: added more unit tests
Reviewers: rven, igor, kradhakrishnan, IslamAbdelRahman, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D50295
Summary:
This patch fix a race condition in persisting options which will cause a crash when:
* Thread A obtain cf options and start to persist options based on that cf options.
* Thread B kicks in and finish DropColumnFamily and delete cf_handle.
* Thread A wakes up and tries to finish the persisting options and crashes.
Test Plan: Add a test in column_family_test that can reproduce the crash
Reviewers: anthony, IslamAbdelRahman, rven, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D51717
Summary:
D51183 was reverted due to breaking the LITE build.
This diff is the same as D51183 but with a fix for the LITE BUILD(D51693)
Test Plan: run all unit tests
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D51711
Summary:
D50475 enables using SST files for transaction write-conflict checking. In order for this to work, we need to make sure not to compact out SingleDeletes when there is an earlier transaction snapshot(D50295). If there is a long-held snapshot, this could reduce the benefit of the SingleDelete optimization.
This diff allows Transactions to mark snapshots as being used for write-conflict checking. Then, during compaction, we will be able to optimize SingleDeletes better in the future.
This diff adds a flag to SnapshotImpl which is used by Transactions. This diff also passes the earliest write-conflict snapshot's sequence number to CompactionIterator. This diff does not actually change Compaction (after this diff is pushed, D50295 will be able to use this information).
Test Plan: no behavior change, ran existing tests
Reviewers: rven, kradhakrishnan, yhchiang, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D51183
Summary:
This patch fix a race condition in persisting options which will cause a crash when:
* Thread A obtain cf options and start to persist options based on that cf options.
* Thread B kicks in and finish DropColumnFamily and delete cf_handle.
* Thread A wakes up and tries to finish the persisting options and crashes.
Test Plan: Add a test in column_family_test that can reproduce the crash
Reviewers: anthony, IslamAbdelRahman, rven, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D51609
Summary:
Fixes T8781168.
Added a new function EnableAutoCompactions in db.h to be publicly
avialable. This allows compaction to be re-enabled after disabling it via
SetOptions
Refactored code to set the dbptr earlier on in TransactionDB::Open and DB::Open
Temporarily disable auto_compaction in TransactionDB::Open until dbptr is set to
prevent race condition.
Test Plan:
Ran make all check
verified fix on myrocks side:
was able to reproduce the seg fault with
../tools/mysqltest.sh --mem --force rocksdb.drop_table
method was to manually sleep the thread after DB::Open but before TransactionDB ptr was
assigned in transaction_db_impl.cc:
DB::Open(db_options, dbname, column_families_copy, handles, &db);
clock_t goal = (60000 * 10) + clock();
while (goal > clock());
...dbptr(aka rdb) gets assigned below
verified my changes fixed the issue.
Also added unit test 'ToggleAutoCompaction' in transaction_test.cc
Reviewers: hermanlee4, anthony
Reviewed By: anthony
Subscribers: alex, dhruba
Differential Revision: https://reviews.facebook.net/D51147
Summary: When option.db_write_buffer_size is hit, we currently flush all column families. Move to flush the column family with the largest active memt table instead. In this way, we can avoid too many small files in some cases.
Test Plan: Modify test DBTest.SharedWriteBuffer to work with the updated behavior
Reviewers: kradhakrishnan, yhchiang, rven, anthony, IslamAbdelRahman, igor
Reviewed By: igor
Subscribers: march, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D51291
Summary: Handle multiple calls to DBImpl::PauseBackgroundWork() and DBImpl::ContinueBackgroundWork()
Test Plan: rocksdb.information_schema handles this case.
Reviewers: igor
Reviewed By: igor
Subscribers: hermanlee4, jkedgar, dhruba
Differential Revision: https://reviews.facebook.net/D50781
Summary:
Since level 0 files can overlap, two level 0 compactions cannot
run in parallel. Compact files needs to check this before running a
compaction.
Test Plan: CompactFilesTest.L0ConflictsFiles
Reviewers: igor, IslamAbdelRahman, anthony, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D50079
Summary:
There's no need for WriteImpl to flatten the write batch group
into a single WriteBatch if the WAL is disabled. This diff moves the
flattening into the WAL step, and skips flattening entirely if it isn't
needed. It's good for about 5% speedup on a multi-threaded workload
with no WAL.
This diff also adds clarifying comments about the chance for partial
failure of WriteBatchInternal::InsertInto, and always sets bg_error_ if
the memtable state diverges from the logged state or if a WriteBatch
succeeds only partially.
Benchmark for speedup:
db_bench -benchmarks=fillrandom -threads=16 -batch_size=1 -memtablerep=skip_list -value_size=0 --num=200000 -level0_slowdown_writes_trigger=9999 -level0_stop_writes_trigger=9999 -disable_auto_compactions --max_write_buffer_number=8 -max_background_flushes=8 --disable_wal --write_buffer_size=160000000
Test Plan: asserts + make check
Reviewers: sdong, igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D50583
Summary:
This patch allows rocksdb to persist options into a file on
DB::Open, SetOptions, and Create / Drop ColumnFamily.
Options files are created under the same directory as the rocksdb
instance.
In addition, this patch also adds a fail_if_missing_options_file in DBOptions
that makes any function call return non-ok status when it is not able to
persist options properly.
// If true, then DB::Open / CreateColumnFamily / DropColumnFamily
// / SetOptions will fail if options file is not detected or properly
// persisted.
//
// DEFAULT: false
bool fail_if_missing_options_file;
Options file names are formatted as OPTIONS-<number>, and RocksDB
will always keep the latest two options files.
Test Plan:
Add options_file_test.
options_test
column_family_test
Reviewers: igor, IslamAbdelRahman, sdong, anthony
Reviewed By: anthony
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48285
Summary:
MyRocks testing found an issue that while iterating over keys
that are outside the prefix, sometimes wrong results were seen for keys
outside the prefix. We now tighten the range of keys seen with a new
read option called prefix_seen_at_start. This remembers the starting
prefix and then compares it on a Next for equality of prefix. If they
are from a different prefix, it sets valid to false.
Test Plan: PrefixTest.PrefixValid
Reviewers: IslamAbdelRahman, sdong, yhchiang, anthony
Reviewed By: anthony
Subscribers: spetrunia, hermanlee4, yoshinorim, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D50211
Summary:
This patch adds GetAggregatedIntProperty() that returns the aggregated
value from all CFs
Test Plan: Added a test in db_test
Reviewers: igor, sdong, anthony, IslamAbdelRahman, rven
Reviewed By: rven
Subscribers: rven, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D49497
Summary:
Update DB::AddFile() restrictions to be
- Key range in loaded table file don't overlap with existing keys or tombstones in DB.
- No other writes happen during AddFile call.
The updated AddFile() will verify that the file key range don't overlap with any keys or tombstones in the DB, and then add the file to L0
Test Plan: unit tests
Reviewers: igor, rven, anthony, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: adsharma, ameyag, dhruba
Differential Revision: https://reviews.facebook.net/D49233
Summary:
CreateLoggerFromOptions have some parameters like db_log_dir and env, these parameters are redundant since they already exist in DBOptions
this patch remove the redundant parameters and expose CreateLoggerFromOptions to users
Test Plan: make check
Reviewers: igor, anthony, yhchiang, rven, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: dhruba, hermanlee4
Differential Revision: https://reviews.facebook.net/D49713
Summary: Run "make format" for some recent commits.
Test Plan: Build and run tests
Reviewers: IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D49707
Summary:
An uninitialized parameter was being passed into the call to fetch the table
properties during the compaction notification callbacks.
Test Plan:
Build it with myrocks and verify unit test passed.
Run unit tests.
Reviewers: rven, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D49635
Summary: As above.
Test Plan: USE_CLANG=1 make check -j
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48981
We will need the log number to validate the recycle-style CRCs. The log
is helpful for debugging, but optional, as not all callers have it.
Signed-off-by: Sage Weil <sage@redhat.com>
When we recycle log files, we need to mix the log number into the CRC
for each record. Note that for logs that don't get recycled (like the
manifest), we always pass a log_number of 0 and false.
Signed-off-by: Sage Weil <sage@redhat.com>
If log recycling is enabled, put old WAL files on a recycle queue instead of
deleting them. When we need a new log file, take a recycled file off the
list if one is available.
Signed-off-by: Sage Weil <sage@redhat.com>
Summary: In MyRocks, it is sometimes important to get propeties only for the subset of the database. This diff implements the API in RocksDB.
Test Plan: ran the GetPropertiesOfTablesInRange
Reviewers: rven, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48651
Summary:
Add rocksdb.num-running-compactions and rocksdb.num-running-flushes
to GetIntProperty() that reports the number of currently running
compactions / flushes.
Test Plan: augmented existing tests in db_test
Reviewers: igor, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D48693
Summary:
Add kill points in:
1. after creating a file
2. before writing a manifest record
3. before syncing manifest
4. before creating a new current file
5. after creating a new current file
Test Plan: Run all current tests.
Reviewers: yhchiang, igor, anthony, IslamAbdelRahman, rven, kradhakrishnan
Reviewed By: kradhakrishnan
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D48855
Summary:
We are cleaning up dependencies.
This diff takes a first step at moving memtable files to their own
directory called memtable. In future diffs, we will move other memtable
files from db to memtable.
Test Plan: make check
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D48915
Summary: db_test_util is used in multiple test files but it dont compile under ROCKSDB_LITE
Test Plan:
make check
make static_lib
OPT=-DROCKSDB_LITE make db_wal_test
Reviewers: igor, yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48579
Summary:
Separate a new class InternalIterator from class Iterator, when the look-up is done internally, which also means they operate on key with sequence ID and type.
This change will enable potential future optimizations but for now InternalIterator's functions are still the same as Iterator's.
At the same time, separate the cleanup function to a separate class and let both of InternalIterator and Iterator inherit from it.
Test Plan: Run all existing tests.
Reviewers: igor, yhchiang, anthony, kradhakrishnan, IslamAbdelRahman, rven
Reviewed By: rven
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D48549
Summary:
Long time ago we add InternalDumpCommand to ldb_tool https://reviews.facebook.net/D11517
This command is using TEST_NewInternalIterator although it's not a test. This patch move TEST_NewInternalIterator outside of db_impl_debug.cc
Test Plan:
make check
make static_lib
Reviewers: yhchiang, igor, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48561
Summary: It would be nice to have and access to table properties in compaction callbacks. In MyRocks project, it will make possible to update optimizer statistics online.
Test Plan: ran the unit test. Ran myrocks with the new way of collecting stats.
Reviewers: igor, rven, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48267
Summary: Pass column family ID through TablePropertiesCollectorFactory::CreateTablePropertiesCollector() so that users can identify which column family this file is for and handle it differently.
Test Plan: Add unit test scenarios in tests related to table properties collectors to verify the information passed in is correct.
Reviewers: rven, yhchiang, anthony, kradhakrishnan, igor, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: yoshinorim, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D48411
Summary:
Handle SST files with both ".sst" and ".ldb" suffix.
This enables user to migrate from leveldb to rocksdb.
Test Plan:
Added unit test with DB operating on SSTs with names schema.
See db/dc_test.cc:SSTsWithLdbSuffixHandling for details
Reviewers: yhchiang, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D48003
Summary:
To support a new MongoDB capability, we need to make sure that we don't do any IO for a short period of time. For background, see:
* https://jira.mongodb.org/browse/SERVER-20704
* https://jira.mongodb.org/browse/SERVER-18899
To implement that, I add a new API calls PauseBackgroundWork() and ContinueBackgroundWork() which reuse the capability we already have in place for RefitLevel() function.
Test Plan: Added a new test in db_test. Made sure that test fails when PauseBackgroundWork() is commented out.
Reviewers: IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D47901
Summary:
This is an initial version of bulk load feature
This diff allow us to create sst files, and then bulk load them later, right now the restrictions for loading an sst file are
(1) Memtables are empty
(2) Added sst files have sequence number = 0, and existing values in database have sequence number = 0
(3) Added sst files values are not overlapping
Test Plan: unit testing
Reviewers: igor, ott, sdong
Reviewed By: sdong
Subscribers: leveldb, ott, dhruba
Differential Revision: https://reviews.facebook.net/D39081
Summary: https://reviews.facebook.net/D23343 changed WAL sync bytes to extra fsync. This change does the same for internal stats.
Test Plan: Run all existing unit tests and verify results in db_bench.
Reviewers: anthony, rven, igor, MarkCallaghan, kradhakrishnan, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D47349
Summary:
This patch fixes#7460559. It introduces SingleDelete as a new database
operation. This operation can be used to delete keys that were never
overwritten (no put following another put of the same key). If an overwritten
key is single deleted the behavior is undefined. Single deletion of a
non-existent key has no effect but multiple consecutive single deletions are
not allowed (see limitations).
In contrast to the conventional Delete() operation, the deletion entry is
removed along with the value when the two are lined up in a compaction. Note:
The semantics are similar to @igor's prototype that allowed to have this
behavior on the granularity of a column family (
https://reviews.facebook.net/D42093 ). This new patch, however, is more
aggressive when it comes to removing tombstones: It removes the SingleDelete
together with the value whenever there is no snapshot between them while the
older patch only did this when the sequence number of the deletion was older
than the earliest snapshot.
Most of the complex additions are in the Compaction Iterator, all other changes
should be relatively straightforward. The patch also includes basic support for
single deletions in db_stress and db_bench.
Limitations:
- Not compatible with cuckoo hash tables
- Single deletions cannot be used in combination with merges and normal
deletions on the same key (other keys are not affected by this)
- Consecutive single deletions are currently not allowed (and older version of
this patch supported this so it could be resurrected if needed)
Test Plan: make all check
Reviewers: yhchiang, sdong, rven, anthony, yoshinorim, igor
Reviewed By: igor
Subscribers: maykov, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D43179
Summary:
Some users have observed errors in the log file when
the log file or sst file is already deleted.
Test Plan:
Make sure that the errors do not appear for already deleted
files.
Reviewers: sdong
Reviewed By: sdong
Subscribers: anthony, kradhakrishnan, yhchiang, rven, igor, IslamAbdelRahman, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D47115
Summary: Now DB::Open() flushes info log before printing DB pointer, so it may not show up if no activity after DB open. Move log flushing from after printing options to printing DB pointer.
Test Plan: make commit-prereq
Reviewers: igor, IslamAbdelRahman, yhchiang, kradhakrishnan, anthony, rven
Reviewed By: rven
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D47121
Summary: Change the log level of DB start-up log from Warn to Header.
Test Plan: db_bench and observe the LOG header
Reviewers: igor, anthony, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D47067
Summary: This will unblock the corresponding change in MyRocks
Test Plan: ran rocksdb.write_sync test
Reviewers: sdong, kolmike
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D46911
Summary:
Releasing mutex between getting min_pending_output and scanning files may cause min_pending_output to be max but some non-final files are found in file scanning, ending up with deleting wrong files.
As a recent regression, mutex can be released while waiting for log sync. We move it to after file scanning.
Test Plan: Run all existing tests. Don't think it is easy to write a unit test. Maybe we should find a way to assert lock not released so that we can have some test verification for similar cases.
Reviewers: igor, anthony, IslamAbdelRahman, kradhakrishnan, yhchiang, kolmike, rven
Reviewed By: rven
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D46899
Summary: The current code, considers data to be consistent if the record
checksum passes. We do have customer issues where the record checksum passed but
the data was incomprehensible. There is no way to get out of this error case
since all WAL recovery model will consider this error as unrelated to WAL.
Relaxing the definition and including errors while inserting to memtable as WAL
errors and handing them as per the recovery level.
Test Plan: Used customer dump to verify the fix for different level. The db
opens for kSkipAnyCorruptedRecords and kPointInTimeRecovery, but fails for
kAbsoluteConsistency and kTolerateCorruptedTailRecords.
Reviewers: sdon igor
CC: leveldb@
Task ID: #7918721
Blame Rev:
Summary: We should never set max_open_files to be bigger than the system's ulimit. Otherwise we will get "Too many open files" errors. See an example in this Travis run: https://travis-ci.org/facebook/rocksdb/jobs/79591566
Test Plan:
make check
I will also verify that max_max_open_files is reasonable.
Reviewers: anthony, kradhakrishnan, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D46551
Summary:
This diff is a collection of cleanups that were initially part of D43179.
Additionally it adds a unified way of defining key-value maps that use a
Comparator for sorting (this was previously implemented in four different
places).
Test Plan: make clean check all
Reviewers: rven, anthony, yhchiang, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D45993
Summary:
MarkLogsSynced() was doing `logs_.erase(it++);`. The standard is saying:
```
all iterators and references are invalidated, unless the erased members are at an end (front or back) of the deque (in which case only iterators and references to the erased members are invalidated)
```
Because `it` is an iterator to the first element of the container, it is
invalidated, only one iteration is executed and `log.getting_synced = false;`
is not being done, so `while (logs_.front().getting_synced)` in `WriteImpl()`
is not terminating.
Test Plan: make db_bench && ./db_bench --benchmarks=fillsync
Reviewers: igor, rven, IslamAbdelRahman, anthony, kradhakrishnan, yhchiang, sdong, tnovak
Reviewed By: tnovak
Subscribers: kolmike, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D45807
Summary:
ReadaheadRandomAccessFile acts as a transparent layer on top of RandomAccessFile. When a Read() request is issued, it issues a much bigger request to the OS and caches the result. When a new request comes in and we already have the data cached, it doesn't have to issue any requests to the OS.
We add ReadaheadRandomAccessFile layer only when file is read during compactions.
D45105 was incorrectly closed by Phabricator because I committed it to a separate branch (not master), so I'm resubmitting the diff.
Test Plan: make check
Reviewers: MarkCallaghan, sdong
Reviewed By: sdong
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D45123
Summary:
See task #7983654. The example was triggering an assert in compaction job
because the compaction was not marked as manual. With this patch,
CompactionPicker::FormCompaction() marks compactions as manual. This patch
also fixes a couple of typos, adds optimistic_transaction_example to
.gitignore and librocksdb as a dependency for examples. Adding librocksdb as
a dependency makes sure that the examples are built with the latest changes
in librocksdb.
Test Plan: make clean && cd examples && make all && ./compact_files_example
Reviewers: rven, sdong, anthony, igor, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D45117
Summary:
This patch fixes a race condition in DBTEst.DynamicMemtableOptions. In rare cases,
it was possible that the main thread would fill up both memtables before the flush
job acquired its work. Then, the flush job was flushing both memtables together,
producing only one L0 file while the test expected two. Now, the test waits for
flushes to finish earlier, to make sure that the memtables are flushed in separate
flush jobs.
Test Plan:
Insert "usleep(10000);" after "IOSTATS_SET_THREAD_POOL_ID(Env::Priority::HIGH);" in BGWorkFlush()
to make the issue more likely. Then test with:
make db_test && time while ./db_test --gtest_filter=*DynamicMemtableOptions; do true; done
Reviewers: rven, sdong, yhchiang, anthony, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D45429
Summary:
Currently, we only purge duplicate keys and deletions during flush if `earliest_seqno_in_memtable <= newest_snapshot`. This means that the newest snapshot happened before we first created the memtable. This is almost never true for MyRocks and MongoRocks.
This patch makes purging during flush able to understand snapshots. The main logic is copied from compaction_job.cc, although the logic over there is much more complicated and extensive. However, we should try to merge the common functionality at some point.
I need this patch to implement no_overwrite_i_promise functionality for flush. We'll also need this to support SingleDelete() during Flush(). @yoshinorim requested the feature.
Test Plan:
make check
I had to adjust some unit tests to understand this new behavior
Reviewers: yhchiang, yoshinorim, anthony, sdong, noetzli
Reviewed By: noetzli
Subscribers: yoshinorim, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42087
Summary: Update DestroyDB so that all SST files in the first path id go through DeleteScheduler instead of being deleted immediately
Test Plan: added a unittest
Reviewers: igor, yhchiang, anthony, kradhakrishnan, rven, sdong
Reviewed By: sdong
Subscribers: jeanxu2012, dhruba
Differential Revision: https://reviews.facebook.net/D44955
Summary:
In prepration for running multiple threads at the same time during
a compaction job, this patch assigns each subcompaction its own state
(instead of sharing the one global CompactionState). Each subcompaction then
uses this state to update its statistics, keep track of its snapshots, etc.
during the course of execution. Then at the end of all the executions the
statistics are aggregated across the subcompactions so that the final result
is the same as if only one larger compaction had run.
Test Plan: ./db_test ./db_compaction_test ./compaction_job_test
Reviewers: sdong, anthony, igor, noetzli, yhchiang
Reviewed By: yhchiang
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D43239
Summary: In internal stats, remember read latency histogram, if statistics is enabled. It can be retrieved from DB::GetProperty() with "rocksdb.dbstats" property, if it is enabled.
Test Plan: Manually run db_bench and prints out "rocksdb.dbstats" by hand and make sure it prints out as expected
Reviewers: igor, IslamAbdelRahman, rven, kradhakrishnan, anthony, yhchiang
Reviewed By: yhchiang
Subscribers: MarkCallaghan, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D44193
Summary:
This diff allows a Writer to join the next write batch group
without acquiring any locks. Waiting is performed via a per-Writer mutex,
so all of the non-leader writers never need to acquire the db mutex.
It is now possible to join a write batch group after the leader has been
chosen but before the batch has been constructed. This diff doesn't
increase parallelism, but reduces synchronization overheads.
For some CPU-bound workloads (no WAL, RAM-sized working set) this can
substantially reduce contention on the db mutex in a multi-threaded
environment. With T=8 N=500000 in a CPU-bound scenario (see the test
plan) this is good for a 33% perf win. Not all scenarios see such a
win, but none show a loss. This code is slightly faster even for the
single-threaded case (about 2% for the CPU-bound scenario below).
Test Plan:
1. unit tests
2. COMPILE_WITH_TSAN=1 make check
3. stress high-contention scenarios with db_bench -benchmarks=fillrandom -threads=$T -batch_size=1 -memtablerep=skip_list -value_size=0 --num=$N -level0_slowdown_writes_trigger=9999 -level0_stop_writes_trigger=9999 -disable_auto_compactions --max_write_buffer_number=8 -max_background_flushes=8 --disable_wal --write_buffer_size=160000000
Reviewers: sdong, igor, rven, ljin, yhchiang
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D43887
Summary:
Add options.compaction_measure_io_stats to print out / pass to listener accumulated time spent on write calls. Example outputs in info logs:
2015/08/12-16:27:59.463944 7fd428bff700 (Original Log Time 2015/08/12-16:27:59.463922) EVENT_LOG_v1 {"time_micros": 1439422079463897, "job": 6, "event": "compaction_finished", "output_level": 1, "num_output_files": 4, "total_output_size": 6900525, "num_input_records": 111483, "num_output_records": 106877, "file_write_nanos": 15663206, "file_range_sync_nanos": 649588, "file_fsync_nanos": 349614797, "file_prepare_write_nanos": 1505812, "lsm_state": [2, 4, 0, 0, 0, 0, 0]}
Add two more counters in iostats_context.
Also add a parameter of db_bench.
Test Plan: Add a unit test. Also manually verify LOG outputs in db_bench
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D44115
Summary:
Initial implementation of Pessimistic Transactions. This diff contains the api changes discussed in D38913. This diff is pretty large, so let me know if people would prefer to meet up to discuss it.
MyRocks folks: please take a look at the API in include/rocksdb/utilities/transaction[_db].h and let me know if you have any issues.
Also, you'll notice a couple of TODOs in the implementation of RollbackToSavePoint(). After chatting with Siying, I'm going to send out a separate diff for an alternate implementation of this feature that implements the rollback inside of WriteBatch/WriteBatchWithIndex. We can then decide which route is preferable.
Next, I'm planning on doing some perf testing and then integrating this diff into MongoRocks for further testing.
Test Plan: Unit tests, db_bench parallel testing.
Reviewers: igor, rven, sdong, yhchiang, yoshinorim
Reviewed By: sdong
Subscribers: hermanlee4, maykov, spetrunia, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D40869
Summary:
Visual Studio complains about deque<LogWriterNumber> because LogWriterNumber is non-copyable for its unique_ptr member writer. Move away from it, and do explit free.
It is less safe but I can't think of a better way to unblock it.
Test Plan: valgrind check test
Reviewers: anthony, IslamAbdelRahman, kolmike, rven, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D43647
Summary:
Subj. We really need this feature.
Previous diff D40899 has most of the changes to make this possible, this diff just adds the method.
Test Plan: `make check`, the new test fails without this diff; ran with ASAN, TSAN and valgrind.
Reviewers: igor, rven, IslamAbdelRahman, anthony, kradhakrishnan, tnovak, yhchiang, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, maykov, hermanlee4, yoshinorim, tnovak, dhruba
Differential Revision: https://reviews.facebook.net/D40905
Summary:
Introduce DeleteScheduler that allow enforcing a rate limit on file deletion
Instead of deleting files immediately, files are moved to trash directory and deleted in a background thread that apply sleep penalty between deletes if needed.
I have updated PurgeObsoleteFiles and PurgeObsoleteWALFiles to use the delete_scheduler instead of env_->DeleteFile
Test Plan:
added delete_scheduler_test
existing unit tests
Reviewers: kradhakrishnan, anthony, rven, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D43221
Summary: Fix for universal compaction with trivial move, when the ouput level is 0. The tests where failing. Fixed by allowing normal compaction when output level is 0.
Test Plan: modified test cases run successfully.
Reviewers: sdong, yhchiang, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: anthony, kradhakrishnan, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D42933
Summary:
I'll just copy internal task summary here:
"
This sequence will cause data loss in the middle after an sync write:
non-sync write key 1
flush triggered, not yet scheduled
sync write key 2
system crash
After rebooting, users might see key 2 but not key 1, which violates the API of sync write.
This can be reproduced using unit test FaultInjectionTest::DISABLED_WriteOptionSyncTest.
One way to fix it is for a sync write, if there is outstanding unsynced log files, we need to syc them too.
"
This diff should be considered together with the next diff D40905; in isolation this fix probably could be a little simpler.
Test Plan: `make check`; added a test for that (DBTest.SyncingPreviousLogs) before noticing FaultInjectionTest.WriteOptionSyncTest (keeping both since mine asserts a bit more); both tests fail without this diff; for D40905 stacked on top of this diff, ran tests with ASAN, TSAN and valgrind
Reviewers: rven, yhchiang, IslamAbdelRahman, anthony, kradhakrishnan, igor, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D40899
Summary: Add new CheckFileExists method. Considered changing the FileExists api but didn't want to break anyone's builds.
Test Plan: unit tests
Reviewers: yhchiang, igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42003
Summary: We want to keep Env a think layer for better portability. Less platform dependent codes should be moved out of Env. In this patch, I create a wrapper of file readers and writers, and put rate limiting, write buffering, as well as most perf context instrumentation and random kill out of Env. It will make it easier to maintain multiple Env in the future.
Test Plan: Run all existing unit tests.
Reviewers: anthony, kradhakrishnan, IslamAbdelRahman, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D42321
Summary:
When we first started, max_background_flushes was 0 by default and compaction thread was executing flushes (since there was no flush thread). Then, we switched the default max_background_flushes to 1. However, we still support the case where there is no flush thread and flushes are done in compaction. This is making our code a bit more complicated. By not supporting this use-case we can make our code simpler.
We have a special case that when you set max_background_flushes to 0, we
schedule the flush to execute on the compaction thread.
Test Plan: make check (there might be some unit tests that depend on this behavior)
Reviewers: IslamAbdelRahman, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D41931
Summary: It has been around for a while and it looks like it never found any uses in the wild. It's also complicating our compaction_job code quite a bit. We're deprecating it in 3.13, but will put it back in 3.14 if we actually find users that need this feature.
Test Plan: make check
Reviewers: noetzli, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42405
Summary:
Previous run may leave some SST files with higher file numbers than manifest indicates.
Compaction or flush may start to run while DB::Open() is still going on. SST file garbage collection may happen interleaving with compaction or flush, and overwrite files generated by compaction of flushes after they are generated. This might cause data loss. This possibility of interleaving is recently introduced.
Fix it by not allowing compaction or flush to be scheduled before DB::Open() finishes.
Test Plan: Add a unit test. This verification will have a chance to fail without the fix but doesn't fix without the fix.
Reviewers: kradhakrishnan, anthony, yhchiang, IslamAbdelRahman, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42399
Summary:
Trvial move in universal compaction was failing when trying to move files from levels other than 0.
This was because the DeleteFile while trivially moving, was only deleting files of level 0 which caused duplication of same file in different levels.
This is fixed by passing the right level as argument in the call of DeleteFile while doing trivial move.
Test Plan: ./db_test ran successfully with the new test cases.
Reviewers: sdong
Reviewed By: sdong
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D42135
Summary:
In one of our recent meetings, we discussed deprecating features that are not being actively used. One of those features, at least within Facebook, is timeout_hint. The feature is really nicely implemented, but if nobody needs it, we should remove it from our code-base (until we get a valid use-case). Some arguments:
* Less code == better icache hit rate, smaller builds, simpler code
* The motivation for adding timeout_hint_us was to work-around RocksDB's stall issue. However, we're currently addressing the stall issue itself (see @sdong's recent work on stall write_rate), so we should never see sharp lock-ups in the future.
* Nobody is using the feature within Facebook's code-base. Googling for `timeout_hint_us` also doesn't yield any users.
Test Plan: make check
Reviewers: anthony, kradhakrishnan, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: sdong, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D41937
Summary: This helps Windows port to format their changes, as discussed. Might have formatted some other codes too becasue last 10 commits include more.
Test Plan: Build it.
Reviewers: anthony, IslamAbdelRahman, kradhakrishnan, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D41961
Summary: Print whether fast CRC32 is supported in DB info LOG
Test Plan: Run db_bench and see it prints out correctly.
Reviewers: yhchiang, anthony, kradhakrishnan, igor
Reviewed By: igor
Subscribers: MarkCallaghan, yoshinorim, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D41733
Summary: Change the naming style of getter and setters according to Google C++ style in compaction.h file
Test Plan: Compilation success
Reviewers: sdong
Reviewed By: sdong
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D41265
Summary: This change enables trivial move if all the input files are non onverlapping while doing Universal Compaction.
Test Plan: ./compaction_picker_test and db_test ran successfully with the new testcases.
Reviewers: sdong
Reviewed By: sdong
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D40875
Summary:
This fixes the following scenario we've hit:
- we reached max_total_wal_size, created a new wal and scheduled flushing all memtables corresponding to the old one,
- before the last of these flushes started its column family was dropped; the last background flush call was a no-op; no one removed the old wal from alive_logs_,
- hours have passed and no flushes happened even though lots of data was written; data is written to different column families, compactions are disabled; old column families are dropped before memtable grows big enough to trigger a flush; the old wal still sits in alive_logs_ preventing max_total_wal_size limit from kicking in,
- a few more hours pass and we run out disk space because of one huge .log file.
Test Plan: `make check`; backported the new test, checked that it fails without this diff
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D40893
Summary: Make RocksDb build and run on Windows to be functionally
complete and performant. All existing test cases run with no
regressions. Performance numbers are in the pull-request.
Test plan: make all of the existing unit tests pass, obtain perf numbers.
Co-authored-by: Praveen Rao praveensinghrao@outlook.com
Co-authored-by: Sherlock Huang baihan.huang@gmail.com
Co-authored-by: Alex Zinoviev alexander.zinoviev@me.com
Co-authored-by: Dmitri Smirnov dmitrism@microsoft.com
Summary:
Fixes task 7156865 where a compaction causes a hang in flush
memtable if CancelAllBackgroundWork was called prior to it.
Stack trace is in : https://phabricator.fb.com/P19848829
We end up waiting for a flush which will never happen because there are no background threads.
Test Plan: PreShutdownFlush
Reviewers: sdong, igor
Reviewed By: sdong, igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D40617
Summary: Replace force_bottommost_level_compaction in CompactRangeOption with an option that allow the user to (always skip, always compact, compact if compaction filter is present) the bottommost level for level based compaction.
Test Plan: make check
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D40527
Summary:
Implementation of a table-level row cache.
It only caches point queries done through the `DB::Get` interface, queries done through the `Iterator` interface will completely skip the cache.
Supports snapshots and merge operations.
Test Plan: Ran `make valgrind_check commit-prereq`
Reviewers: igor, philipp, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D39849
Summary:
The "one size fits all" approach with WAL recovery will only introduce inconvenience for our varied clients as we go forward. The current recovery is a bit heuristic. We introduce the following levels of consistency while replaying the WAL.
1. RecoverAfterRestart (kTolerateCorruptedTailRecords)
This mocks the current recovery mode.
2. RecoverAfterCleanShutdown (kAbsoluteConsistency)
This is ideal for unit test and cases where the store is shutdown cleanly. We tolerate no corruption or incomplete writes.
3. RecoverPointInTime (kPointInTimeRecovery)
This is ideal when using devices with controller cache or file systems which can loose data on restart. We recover upto the point were is no corruption or incomplete write.
4. RecoverAfterDisaster (kSkipAnyCorruptRecord)
This is ideal mode to recover data. We tolerate corruption and incomplete writes, and we hop over those sections that we cannot make sense of salvaging as many records as possible.
Test Plan:
(1) Run added unit test to cover all levels.
(2) Run make check.
Reviewers: leveldb, sdong, igor
Subscribers: yoshinorim, dhruba
Differential Revision: https://reviews.facebook.net/D38487
Summary: Fixing bad merge
Test Plan: make -j64 check (this is not enough to verify the fix)
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D40521
Summary:
Currently RocksDB silently ignores this issue and doesn't compress the data. Based on discussion, we agree that this is pretty bad because it can cause confusion for our users.
This patch fails DB::Open() if we don't support the compression that is specified in the options.
Test Plan: make check with LZ4 not present. If Snappy is not present all tests will just fail because Snappy is our default library. We should make Snappy the requirement, since without it our default DB::Open() fails.
Reviewers: sdong, MarkCallaghan, rven, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D39687
Summary:
This is https://reviews.facebook.net/D39999 but after introducing an option to force compaction the bottom most level
Changes in this patch
- Introduce force_bottommost_level_compaction to CompactRangeOptions that force compacting bottommost level during compaction
- Skip bottommost level compaction if we dont have a compaction filter and force_bottommost_level_compaction options is not set
Although tests pass on my machine but I suspect that there maybe some tests that I am not aware of that should use force_bottommost_level_compaction to pass in a deterministic way
Test Plan:
make check
adding new tests
Reviewers: igor, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D40059
Summary:
Universal compaction can involves in multiple levels. However,
the current implementation of bytes_readn and bytes_readnp1
(and some other stats with postfix `n` and `np1`) assumes compaction
can only have two levels.
This patch fixes this bug and redefines bytes_readn and bytes_readnp1:
* bytes_readnp1: the number of bytes read in the compaction output level.
* bytes_readn: the total number of bytes read minus bytes_readnp1
Test Plan: Add a test in compaction_job_stats_test
Reviewers: igor, sdong, rven, anthony, kradhakrishnan, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D40239
Summary:
This diff update DB::CompactRange to use RangeCompactionOptions instead of using multiple parameters
Old CompactRange is still available but deprecated
Test Plan:
make all check
make rocksdbjava
USE_CLANG=1 make all
OPT=-DROCKSDB_LITE make release
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D40209
Summary:
We go to great lengths to make sure MaybeScheduleFlushOrCompaction() is called outside of write thread. But anyway, it's still called in the mutex, so it's not that much cheaper.
This diff removes the "optimization" and cleans up the code a bit.
Test Plan: make check
Reviewers: rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D40113
Summary:
Add an option in GetApproximateSize() so that the result will include estimated sizes in mem tables.
To implement it, implement an estimated count from the beginning to a key in skip list. The approach is to count to find the entry, how many Next() is issued from each level, and sum them with a weight that is <branching factor> ^ <level>.
Test Plan: Add a test case
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D40119
Summary:
Reverting this diff https://reviews.facebook.net/D39999
Will add an option to force bottom most level compaction and then re submit it
Test Plan: make check
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D40041
Summary: If we don't have a compaction filter then we can skip compacting the bottom most level
Test Plan:
make check
added unit tests
Reviewers: yhchiang, sdong, igor
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D39999
Summary:
We slow down data into the database to the rate of options.delayed_write_rate (a new option) with this patch.
The thread synchronization approach I take is to still synchronize write controller by DB mutex and GetDelay() is inside DB mutex. Try to minimize the frequency of getting time in GetDelay(). I verified it through db_bench and it seems to work
hard_rate_limit is deprecated.
options.delayed_write_rate is still not dynamically changeable. Need to work on it as a follow-up.
Test Plan: Add new unit tests in db_test
Reviewers: yhchiang, rven, kradhakrishnan, anthony, MarkCallaghan, igor
Reviewed By: igor
Subscribers: ikabiljo, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D36351
Summary:
Adding largest sequence number to FlushJobInfo
and passing flushed file metadata to NotifyOnFlushCompleted which include alot of other values that we may want to expose in FlushJobInfo
Test Plan: make check
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D39927
Summary:
Add Env::GetThreadID(), which returns the ID of the current thread.
In addition, make GetThreadList() and InfoLog use same unique ID for the same thread.
Test Plan:
db_test
listener_test
Reviewers: igor, rven, IslamAbdelRahman, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D39735
Summary:
Right now the level we pass to ReFitLevel is the maximum level with files (before compaction), there are multiple cases where this maximum level have changed after compaction
- all files where in L0 (now maximum level is L1)
- using kCompactionStyleUniversal (now maximum level in the last level)
- level_compaction_dynamic_level_bytes ??
We can handle each of these cases individually, but I felt it's safer to calculate max_level_with_files again if we want to do a ReFitLevel
Test Plan:
adding some tests
make -j64 check
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: ott, dhruba
Differential Revision: https://reviews.facebook.net/D39663
Summary:
There is a hang during DB close in the following scenario:
a) a load with WAL disabled was done,
b) CancelAllBackgroundWork was called,
c) DB Close was called
This was because in that we will wait for a flush but we cannot do a
background flush because we have called CancelAllBackgroundWork which
marks the DB as shutting downn.
Test Plan: Added DBTest FlushOnDestroy
Reviewers: sdong
Reviewed By: sdong
Subscribers: yoshinorim, hermanlee4, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D39747
Summary: We currently issue malloc and free inside DB mutex in GetSnapshot() and ReleaseSnapshot(). Move them out.
Test Plan:
Go through all tests
make valgrind_check
Reviewers: yhchiang, rven, IslamAbdelRahman, anthony, igor
Reviewed By: igor
Subscribers: maykov, hermanlee4, MarkCallaghan, yoshinorim, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D39753
Summary:
It is experimental. Allow users to return from a call back function TablePropertiesCollector::NeedCompact(), based on the data in the file.
It can be used to allow users to suggest DB to clear up delete tombstones faster.
Test Plan: Add a unit test.
Reviewers: igor, yhchiang, kradhakrishnan, rven
Reviewed By: rven
Subscribers: yoshinorim, MarkCallaghan, maykov, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D39585
Summary:
EventListener::OnFlushCompleted() now passes a structure instead
of a list of parameters. This minimizes the API change in the
future.
Test Plan:
listener_test
compact_files_test
example/compact_files_example
Reviewers: kradhakrishnan, sdong, IslamAbdelRahman, rven, igor
Reviewed By: rven, igor
Subscribers: IslamAbdelRahman, rven, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D39543
Summary: I encountered an issue where the database hang, it looks like the mutex is not unlocked on return in ReFitLevel function
Test Plan: make -j64 check
Reviewers: yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D39609
Summary:
The type of smallest_output_key_prefix and largest_output_key_prefix
have been changed to std::string in https://reviews.facebook.net/D39537.
As a result, we shouldn't do smallest_output_key_prefix[0] = 0 in the
initialization.
Test Plan: compile db_test with tsan enabled and repeat DBTest.CompactionDeletionTrigger test to verify the tsan issue has been gone.
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D39645
Summary:
This diff updates the logic of how we do trivial move, now trivial move can run on any number of files in input level as long as they are not overlapping
The conditions for trivial move have been updated
Introduced conditions:
- Trivial move cannot happen if we have a compaction filter (except if the compaction is not manual)
- Input level files cannot be overlapping
Removed conditions:
- Trivial move only run when the compaction is not manual
- Input level should can contain only 1 file
More context on what tests failed because of Trivial move
```
DBTest.CompactionsGenerateMultipleFiles
This test is expecting compaction on a file in L0 to generate multiple files in L1, this test will fail with trivial move because we end up with one file in L1
```
```
DBTest.NoSpaceCompactRange
This test expect compaction to fail when we force environment to report running out of space, of course this is not valid in trivial move situation
because trivial move does not need any extra space, and did not check for that
```
```
DBTest.DropWrites
Similar to DBTest.NoSpaceCompactRange
```
```
DBTest.DeleteObsoleteFilesPendingOutputs
This test expect that a file in L2 is deleted after it's moved to L3, this is not valid with trivial move because although the file was moved it is now used by L3
```
```
CuckooTableDBTest.CompactionIntoMultipleFiles
Same as DBTest.CompactionsGenerateMultipleFiles
```
This diff is based on a work by @sdong https://reviews.facebook.net/D34149
Test Plan: make -j64 check
Reviewers: rven, sdong, igor
Reviewed By: igor
Subscribers: yhchiang, ott, march, dhruba, sdong
Differential Revision: https://reviews.facebook.net/D34797
Summary:
Add EventListener::OnTableFileDeletion(), which will be
called when a table file is deleted.
Test Plan: Extend three existing tests in db_test to verify the deleted files.
Reviewers: rven, anthony, kradhakrishnan, igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D38931
Summary:
Allow EventListener::OnCompactionCompleted to return CompactionJobStats,
which contains useful information about a compaction.
Example CompactionJobStats returned by OnCompactionCompleted():
smallest_output_key_prefix 05000000
largest_output_key_prefix 06990000
elapsed_time 42419
num_input_records 300
num_input_files 3
num_input_files_at_output_level 2
num_output_records 200
num_output_files 1
actual_bytes_input 167200
actual_bytes_output 110688
total_input_raw_key_bytes 5400
total_input_raw_value_bytes 300000
num_records_replaced 100
is_manual_compaction 1
Test Plan: Developed a mega test in db_test which covers 20 variables in CompactionJobStats.
Reviewers: rven, igor, anthony, sdong
Reviewed By: sdong
Subscribers: tnovak, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D38463
Summary:
Add EventListener::OnTableFileCreated(), which will be called
when a table file is created. This patch is part of the
EventLogger and EventListener integration.
Test Plan: Augment existing test in db/listener_test.cc
Reviewers: anthony, kradhakrishnan, rven, igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D38865
Summary: Add a stats counter for DB_WRITE back which was mistakenly removed.
Test Plan: augment GroupCommitTest
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D39399
Summary:
We occasionally get write stalls (>1s Write() calls) on HDD under read load. The following timers explain almost all of the stalls:
- perf_context.db_mutex_lock_nanos
- perf_context.db_condition_wait_nanos
- iostats_context.open_time
- iostats_context.allocate_time
- iostats_context.write_time
- iostats_context.range_sync_time
- iostats_context.logger_time
In my experiments each of these occasionally takes >1s on write path under some workload. There are rare cases when Write() takes long but none of these takes long.
Test Plan: Added code to our application to write the listed timings to log for slow writes. They usually add up to almost exactly the time Write() call took.
Reviewers: rven, yhchiang, sdong
Reviewed By: sdong
Subscribers: march, dhruba, tnovak
Differential Revision: https://reviews.facebook.net/D39177
Summary: In DB::CompactRange(), change parameter "reduce_level" to "change_level". Users can compact all data to the last level if needed. By doing it, users can migrate the DB to options.level_compaction_dynamic_level_bytes=true.
Test Plan: Add a unit test for it.
Reviewers: yhchiang, anthony, kradhakrishnan, igor, rven
Reviewed By: rven
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D39099
Summary:
DBImpl::notifying_events_ is a internal counter in DBImpl which is
used to prevent DB close when DB is notifying events. However, as
the current events all rely on either compaction or flush which
already have similar counters to prevent DB close, it is safe to
remove notifying_events_.
Test Plan:
listener_test
examples/compact_files_example
Reviewers: igor, anthony, kradhakrishnan, rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D39315
Summary: Broken by optimistic transaction diff. (I only built 'release' not 'static_lib' when testing).
Test Plan: build
Reviewers: yhchiang, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D39219
Summary: Optimistic transactions supporting begin/commit/rollback semantics. Currently relies on checking the memtable to determine if there are any collisions at commit time. Not yet implemented would be a way of enuring the memtable has some minimum amount of history so that we won't fail to commit when the memtable is empty. You should probably start with transaction.h to get an overview of what is currently supported.
Test Plan: Added a new test, but still need to look into stress testing.
Reviewers: yhchiang, igor, rven, sdong
Reviewed By: sdong
Subscribers: adamretter, MarkCallaghan, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D33435
Summary:
For transactions, we are using the memtables to validate that there are no write conflicts. But after flushing, we don't have any memtables, and transactions could fail to commit. So we want to someone keep around some extra history to use for conflict checking. In addition, we want to provide a way to increase the size of this history if too many transactions fail to commit.
After chatting with people, it seems like everyone prefers just using Memtables to store this history (instead of a separate history structure). It seems like the best place for this is abstracted inside the memtable_list. I decide to create a separate list in MemtableListVersion as using the same list complicated the flush/installalflushresults logic too much.
This diff adds a new parameter to control how much memtable history to keep around after flushing. However, it sounds like people aren't too fond of adding new parameters. So I am making the default size of flushed+not-flushed memtables be set to max_write_buffers. This should not change the maximum amount of memory used, but make it more likely we're using closer the the limit. (We are now postponing deleting flushed memtables until the max_write_buffer limit is reached). So while we might use more memory on average, we are still obeying the limit set (and you could argue it's better to go ahead and use up memory now instead of waiting for a write stall to happen to test this limit).
However, if people are opposed to this default behavior, we can easily set it to 0 and require this parameter be set in order to use transactions.
Test Plan: Added a xfunc test to play around with setting different values of this parameter in all tests. Added testing in memtablelist_test and planning on adding more testing here.
Reviewers: sdong, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D37443
Summary:
Rename EventLoggerHelpers EventHelpers, as it's going to include
all event-related helper functions instead of EventLogger only stuffs.
Test Plan: make
Reviewers: sdong, rven, anthony
Reviewed By: anthony
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D39093
Summary: Removed an unused private variable in db_impl.h
Test Plan: make db_test
Reviewers: sdong, anthony, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D38925
Summary:
This patch fixes the following two bugs on logging file deletion.
1. Previously, file deletion failure was only logged in INFO_LEVEL.
This patch changes it to ERROR_LEVEL and does some code clean.
2. EventLogger previously will always generate the same log on
table file deletion even when file deletion is not successful.
Now the resulting status of file deletion will also be logged.
Test Plan: make all check
Reviewers: sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D38817
Summary: Avoid logging under mutex in DBImpl::WriteLevel0TableForRecovery().
Test Plan: make all check
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D38823
Summary: Dump db stats in WARN level
Test Plan: run db_bench and verify the LOG
Reviewers: igor, MarkCallaghan
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D38691
Summary:
sync_file_range is not always asyncronous and thus can block writes if we do this for WAL in the foreground thread. See more here: http://yoshinorimatsunobu.blogspot.com/2014/03/how-syncfilerange-really-works.html
Some users don't want us to call sync_file_range on WALs. Some other do.
Thus, I'm adding a separate option wal_bytes_per_sync to control calling
sync_file_range on WAL files. bytes_per_sync will apply only to table
files now.
Test Plan: no more sync_file_range for WAL as evidenced by strace
Reviewers: yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D38253
Summary: As title. I spent some time thinking about it and I don't think there should be any issue with running manual compaction and flushes in parallel
Test Plan: make check works
Reviewers: rven, yhchiang, sdong
Reviewed By: yhchiang, sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D38355
Summary: CompactRange() now is much more expensive for dynamic level base size as it goes through all the levels. Skip those not used levels between level 0 an base level.
Test Plan: Run all unit tests
Reviewers: yhchiang, rven, anthony, kradhakrishnan, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D37125
Summary:
Added a couple functions to WriteBatchWithIndex to make it easier to query the value of a key including reading pending writes from a batch. (This is needed for transactions).
I created write_batch_with_index_internal.h to use to store an internal-only helper function since there wasn't a good place in the existing class hierarchy to store this function (and it didn't seem right to stick this function inside WriteBatchInternal::Rep).
Since I needed to access the WriteBatchEntryComparator, I moved some helper classes from write_batch_with_index.cc into write_batch_with_index_internal.h/.cc. WriteBatchIndexEntry, ReadableWriteBatch, and WriteBatchEntryComparator are all unchanged (just moved to a different file(s)).
Test Plan: Added new unit tests.
Reviewers: rven, yhchiang, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D38037
Summary:
Couple changes:
1. instead of SnapshotList, just take a vector of snapshots
2. don't take a separate parameter is_snapshots_supported. If there are snapshots in the list, that means they are supported. I actually think we should get rid of this notion of snapshots not being supported.
3. don't pass in mutable_cf_options as a parameter. Lifetime of mutable_cf_options is a bit tricky to maintain, so it's better to not pass it in for the whole compaction job. We only really need it when we install the compaction results.
Test Plan: make check
Reviewers: sdong, rven, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36627
Summary:
CPU profiling reveals GetApproximateSizes as a bottleneck for performance. The current implementation is sub-optimal, it scans every file in every level to compute the result.
We can take advantage of the fact that all levels above 0 are sorted in the increasing order of key ranges and use binary search to locate the starting index. This can reduce the number of comparisons required to compute the result.
Test Plan: We have good test coverage. Run the tests.
Reviewers: sdong, igor, rven, dynamike
Subscribers: dynamike, maykov, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D37755
Summary:
Added these events:
* Recovery start, finish and also when recovery creates a file
* Trivial move
* Compaction start, finish and when compaction creates a file
* Flush start, finish
Also includes small fix to EventLogger
Also added option ROCKSDB_PRINT_EVENTS_TO_STDOUT which is useful when we debug things. I've spent far too much time chasing LOG files.
Still didn't get sst table properties in JSON. They are written very deeply into the stack. I'll address in separate diff.
TODO:
* Write specification. Let's first use this for a while and figure out what's good data to put here, too. After that we'll write spec
* Write tools that parse and analyze LOGs. This can be in python or go. Good intern task.
Test Plan: Ran db_bench with ROCKSDB_PRINT_EVENTS_TO_STDOUT. Here's the output: https://phabricator.fb.com/P19811976
Reviewers: sdong, yhchiang, rven, MarkCallaghan, kradhakrishnan, anthony
Reviewed By: anthony
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D37521
Summary:
CompactRange for universal compaction with num_levels > 1 seems to have a bug. The unit test also has a bug so it doesn't capture the problem.
Fix it. Revert the compact range to the logic equivalent to num_levels=1. Always compact all files together.
It should also fix DBTest.IncreaseUniversalCompactionNumLevels. The issue was that options.write_buffer_size = 100 << 10 and options.write_buffer_size = 100 << 10 are not used in later test scenarios. So write_buffer_size of 4MB was used. The compaction trigger condition is not anymore obvious as expected.
Test Plan: Run the new test and all test suites
Reviewers: yhchiang, rven, kradhakrishnan, anthony, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D37551
Summary:
Based on feedback from D37083.
Are all of these correct? In some spaces it seems like we're doing SetMaxPossibleForUserKey() although we want the smallest possible internal key for user key.
Test Plan: make check
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D37341
Summary: D36669 introduces a bug that trivial moved data is not going to specific level but the next level, which will incorrectly be level 1 for level 0 compaciton if base level is not level 1. Fixing it by appreciating the output level
Test Plan: Run all tests
Reviewers: MarkCallaghan, rven, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D37119
Summary:
The goal of this diff is to make Compaction class easier to use. This should also make new compaction algorithms easier to write (like CompactFiles from @yhchiang and dynamic leveled and multi-leveled universal from @sdong).
Here are couple of things demonstrating that Compaction class is hard to use:
1. we have two constructors of Compaction class
2. there's this thing called grandparents_, but it appears to only be setup for leveled compaction and not compactfiles
3. it's easy to introduce a subtle and dangerous bug like this: D36225
4. SetupBottomMostLevel() is hard to understand and it shouldn't be. See this comment: afbafeaeae/db/compaction.cc (L236-L241). It also made it harder for @yhchiang to write CompactFiles, as evidenced by this: afbafeaeae/db/compaction_picker.cc (L204-L210)
The problem is that we create Compaction object, which holds a lot of state, and then pass it around to some functions. After those functions are done mutating, then we call couple of functions on Compaction object, like SetupBottommostLevel() and MarkFilesBeingCompacted(). It is very hard to see what's happening with all that Compaction's state while it's travelling across different functions. If you're writing a new PickCompaction() function you need to try really hard to understand what are all the functions you need to run on Compaction object and what state you need to setup.
My proposed solution is to make important parts of Compaction immutable after construction. PickCompaction() should calculate compaction inputs and then pass them onto Compaction object once they are finalized. That makes it easy to create a new compaction -- just provide all the parameters to the constructor and you're done. No need to call confusing functions after you created your object.
This diff doesn't fully achieve that goal, but it comes pretty close. Here are some of the changes:
* have one Compaction constructor instead of two.
* inputs_ is constant after construction
* MarkFilesBeingCompacted() is now private to Compaction class and automatically called on construction/destruction.
* SetupBottommostLevel() is gone. Compaction figures it out on its own based on the input.
* CompactionPicker's functions are not passing around Compaction object anymore. They are only passing around the state that they need.
Test Plan:
make check
make asan_check
make valgrind_check
Reviewers: rven, anthony, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: sdong, yhchiang, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36687
Summary:
Fix a compile error in ROCKSDB_LITE in db/db_impl.cc
related to internal_stats.
Test Plan: make OPT=-DROCKSDB_LITE shared_lib
Reviewers: sdong, igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36819
Summary: Now EnvOptions uses unsanitized DB options. bytes_per_sync is tuned off when rate_limiter is used, but this change doesn't take effort.
Test Plan: See different I/O pattern in db_bench running fillseq.
Reviewers: yhchiang, kradhakrishnan, rven, anthony, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D36723
Summary: Now we add warnings when user configures compression and the compression is not supported.
Test Plan:
Configured compression to non-supported values. Observed messages in my log:
2015/03/26-12:17:57.586341 7ffb8a496840 [WARN] Compression type chosen for level 2 is not supported: LZ4. RocksDB will not compress data on level 2.
2015/03/26-12:19:10.768045 7f36f15c5840 [WARN] Compression type chosen is not supported: LZ4. RocksDB will not compress data.
Reviewers: rven, sdong, yhchiang
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D35979
Summary:
Currently users have no idea a key is add, delete or merge from TablePropertiesCollector call back. Add a new function to add it.
Also refactor the codes so that
(1) make table property collector and internal table property collector two separate data structures with the later one now exposed
(2) table builders only receive internal table properties
Test Plan: Add cases in table_properties_collector_test to cover both of old and new ways of using TablePropertiesCollector.
Reviewers: yhchiang, igor.sugak, rven, igor
Reviewed By: rven, igor
Subscribers: meyering, yoshinorim, maykov, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D35373
Summary:
With this change, we use L1 and up to store compaction outputs in universal compaction.
The compaction pick logic stays the same. Outputs are stored in the largest "level" as possible.
If options.num_levels=1, it behaves all the same as now.
Test Plan:
1) convert most of existing unit tests for universal comapaction to include the option of one level and multiple levels.
2) add a unit test to cover parallel compaction in universal compaction and run it in one level and multiple levels
3) add unit test to migrate from multiple level setting back to one level setting
4) add a unit test to insert keys to trigger multiple rounds of compactions and verify results.
Reviewers: rven, kradhakrishnan, yhchiang, igor
Reviewed By: igor
Subscribers: meyering, leveldb, MarkCallaghan, dhruba
Differential Revision: https://reviews.facebook.net/D34539
Summary:
Cleaning up log files can do heavy IO, since we call ftruncate() in the destructor. We don't want to call ftruncate() in user threads.
This diff moves cleaning to background threads (flush and compaction)
Test Plan: make check, will also run valgrind
Reviewers: yhchiang, rven, MarkCallaghan, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36177
Summary:
Assign the string properties to const string variables under the
DB::Properties namespace. This helps catch typos during compilation and
also consolidates the property definition in one place.
Test Plan: Run rocksdb unit tests
Reviewers: sdong, yoshinorim, igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D35991
Summary: It's useful to know if we have compression support or no
Test Plan:
Observed this in my LOG:
2015/03/26-10:34:35.460681 7f5b322b7840 Snappy supported
2015/03/26-10:34:35.460682 7f5b322b7840 Zlib supported
2015/03/26-10:34:35.460686 7f5b322b7840 Bzip supported
2015/03/26-10:34:35.460687 7f5b322b7840 LZ4 NOT supported
Reviewers: sdong, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D35955
Summary:
Improve ThreadStatusSingleCompaction in two ways:
1. Use SYNC_POINT to ensure compaction won't happen
before the test finishes its "Put Phase" instead of
using sleep.
2. In Put Phase, it continues until we have sufficient
number of L0 files. Note that during the put phase,
there won't be any compaction that consumes L0 files
because of item 1.
Test Plan: ./db_test --gtest_filter="*ThreadStatusSingleCompaction*"
Reviewers: sdong, igor, rven
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D35727
Summary:
To understand the bug read t5943287 and check out the new test in column_family_test (ReadDroppedColumnFamily), iter 0.
RocksDB contract allowes you to read a drop column family as long as there is a live reference. However, since our iteration ignores dropped column families, AddLiveFiles() didn't mark files of a dropped column families as live. So we deleted them.
In this patch I no longer ignore dropped column families in the iteration. I think this behavior was confusing and it also led to this bug. Now if an iterator client wants to ignore dropped column families, he needs to do it explicitly.
Test Plan: Added a new unit test that is failing on master. Unit test succeeds now.
Reviewers: sdong, rven, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D32535
Summary: It is no longer used by the implementation, so we should also remove it from the public API.
Test Plan: make check
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D34971
Summary: Some suggestions for cleanup from Igor.
Test Plan: Regression tests.
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D35169
Summary:
On RocksDB, when there are multiple instances doing
flushes/compactions in the background, the close call takes a long time
because the flushes/compactions need to complete before the database can
shut down. If another instance is using the background threads and the compaction for this instance is in the queue since it has been scheduled, we still cannot shutdown. We now remove the scheduled background tasks which have not yet started running, so that shutdown is speeded up.
Test Plan: DB Test added.
Reviewers: yhchiang, igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D33741
Summary:
Here's my proposal for making our LOGs easier to read by machines.
The idea is to dump all events as JSON objects. JSON is easy to read by humans, but more importantly, it's easy to read by machines. That way, we can parse this, load into SQLite/mongo and then query or visualize.
I started with table_create and table_delete events, but if everybody agrees, I'll continue by adding more events (flush/compaction/etc etc)
Test Plan:
Ran db_bench. Observed:
2015/01/15-14:13:25.788019 1105ef000 EVENT_LOG_v1 {"time_micros": 1421360005788015, "event": "table_file_creation", "file_number": 12, "file_size": 1909699}
2015/01/15-14:13:25.956500 110740000 EVENT_LOG_v1 {"time_micros": 1421360005956498, "event": "table_file_deletion", "file_number": 12}
Reviewers: yhchiang, rven, dhruba, MarkCallaghan, lgalanis, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D31647
Summary:
Provide an API which enables users to infor Rocksdb that it is
shutting down.
Test Plan: db_test
Reviewers: sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D34617
