Commit Graph

900 Commits

Author SHA1 Message Date
Yueh-Hsuan Chiang
24110ce90c Correct Statistics FLUSH_WRITE_BYTES
Summary:
In https://reviews.facebook.net/D56271, we fixed an issue where
we consider flush as compaction.  However, that makes us mistakenly
count FLUSH_WRITE_BYTES twice (one in flush_job and one in db_impl.)

This patch removes the one incremented in db_impl.

Test Plan: db_test

Reviewers: yiwu, andrewkr, IslamAbdelRahman, kradhakrishnan, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D57111
2016-04-25 12:01:01 -07:00
sdong
4b6833aec1 Rename options.compaction_measure_io_stats to options.report_bg_io_stats and include flush too.
Summary: It is useful to print out IO stats in flush jobs too. Extend options.compaction_measure_io_stats to flush jobs and raname it.

Test Plan: Try db_bench and see the stats are printed out.

Reviewers: yhchiang

Reviewed By: yhchiang

Subscribers: kradhakrishnan, yiwu, IslamAbdelRahman, leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D56769
2016-04-15 10:22:18 -07:00
Jay Edgar
2448f80375 Make sure that if use_mmap_reads is on use_os_buffer is also on
Summary: The code assumes that if use_mmap_reads is on then use_os_buffer is also on.  This make sense as by using memory mapped files for reading you are expecting the OS to cache what it needs.  Add code to make sure the user does not turn off use_os_buffer when they turn on use_mmap_reads

Test Plan: New test: DBTest.MMapAndBufferOptions

Reviewers: sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D56397
2016-04-08 14:30:15 -07:00
Andrew Kryczka
2391ef7214 Embed column family name in SST file
Summary:
Added the column family name to the properties block. This property
is omitted only if the property is unavailable, such as when RepairDB()
writes SST files.

In a next diff, I will change RepairDB to use this new property for
deciding to which column family an existing SST file belongs. If this
property is missing, it will add it to the "unknown" column family (same
as its existing behavior).

Test Plan:
New unit test:

  $ ./db_table_properties_test --gtest_filter=DBTablePropertiesTest.GetColumnFamilyNameProperty

Reviewers: IslamAbdelRahman, yhchiang, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D55605
2016-04-06 23:10:32 -07:00
Marton Trencseni
9b51987521 Adding pin_l0_filter_and_index_blocks_in_cache feature and related fixes.
Summary:
When a block based table file is opened, if prefetch_index_and_filter is true, it will prefetch the index and filter blocks, putting them into the block cache.
What this feature adds: when a L0 block based table file is opened, if pin_l0_filter_and_index_blocks_in_cache is true in the options (and prefetch_index_and_filter is true), then the filter and index blocks aren't released back to the block cache at the end of BlockBasedTableReader::Open(). Instead the table reader takes ownership of them, hence pinning them, ie. the LRU cache will never push them out. Meanwhile in the table reader, further accesses will not hit the block cache, thus avoiding lock contention.

Test Plan:
'export TEST_TMPDIR=/dev/shm/ && DISABLE_JEMALLOC=1 OPT=-g make all valgrind_check -j32' is OK.
I didn't run the Java tests, I don't have Java set up on my devserver.

Reviewers: sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D56133
2016-04-01 10:42:39 -07:00
zensan
78711524b7 In all the places where log records are read, there was a check that
record.size() should not be less than 12.

This "magic number" seems to be the WriteBatch header (8 byte sequence
and 4 byte count).   Replaced all the places where "12" was used
by WriteBatchInternal::kHeader.
2016-03-30 23:05:22 +05:30
Praveen Rao
583157f710 Avoid overloaded virtual function 2016-03-22 17:10:31 -07:00
Praveen Rao
4f1c74a46e merge from master 2016-03-18 12:48:01 -07:00
Praveen Rao
f8c2189307 Publish log numbers for column family to wal_filter, and provide log number in the record callback 2016-03-18 12:32:15 -07:00
Baris Yazici
e8e6cf0173 fix: handle_fatal_signal (sig=6) in std::vector<std::string, std::allocator<std::string> >::_M_range_check | c++/4.8.2/bits/stl_vector.h:794 #174
Summary:
Fix for https://github.com/facebook/mysql-5.6/issues/174

When there is no old files to purge, vector.at(i) function was crashing

if (old_info_log_file_count != 0 &&
      old_info_log_file_count >= db_options_.keep_log_file_num) {
    std::sort(old_info_log_files.begin(), old_info_log_files.end());
    size_t end = old_info_log_file_count - db_options_.keep_log_file_num;
    for (unsigned int i = 0; i <= end; i++) {
      std::string& to_delete = old_info_log_files.at(i);

Added check to old_info_log_file_count be non zero.

Test Plan: run existing tests

Reviewers: gunnarku, vasilep, sdong, yhchiang

Reviewed By: yhchiang

Subscribers: andrewkr, webscalesql-eng, dhruba

Differential Revision: https://reviews.facebook.net/D55245
2016-03-11 11:11:45 -08:00
Andrew Kryczka
d9620239d2 Cleanup stale manifests outside of full purge
Summary:
- Keep track of obsolete manifests in VersionSet
- Updated FindObsoleteFiles() to put obsolete manifests in the JobContext for later use by PurgeObsoleteFiles()
- Added test case that verifies a stale manifest is deleted by a non-full purge

Test Plan:
  $ ./backupable_db_test --gtest_filter=BackupableDBTest.ChangeManifestDuringBackupCreation

Reviewers: IslamAbdelRahman, yoshinorim, sdong

Reviewed By: sdong

Subscribers: andrewkr, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D55269
2016-03-10 18:16:21 -08:00
Yueh-Hsuan Chiang
765597fa78 Update compaction score right after CompactFiles forms a compaction
Summary:
This is a follow-up patch of https://reviews.facebook.net/D54891.
As the information about files being compacted will also be used
when making compaction decision, it is necessary to update the compaction
score when a compaction plan has been made but not yet execute.

This patch adds a missing call to update the compaction score in
CompactFiles().

Test Plan: compact_files_test

Reviewers: sdong, IslamAbdelRahman, kradhakrishnan, yiwu, andrewkr

Reviewed By: andrewkr

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D55227
2016-03-10 14:34:28 -08:00
Yueh-Hsuan Chiang
a7d4eb2f34 Fix a bug where flush does not happen when a manual compaction is running
Summary:
Currently, when rocksdb tries to run manual compaction to refit data into a level,
there's a ReFitLevel() process that requires no bg work is currently running.
When RocksDB plans to ReFitLevel(), it will do the following:

 1. pause scheduling new bg work.
 2. wait until all bg work finished
 3. do the ReFitLevel()
 4. unpause scheduling new bg work.

However, as it pause scheduling new bg work at step one and waiting for all bg work
finished in step 2, RocksDB will stop flushing until all bg work is done (which
could take a long time.)

This patch fix this issue by changing the way ReFitLevel() pause the background work:

1. pause scheduling compaction.
2. wait until all bg work finished.
3. pause scheduling flush
4. do ReFitLevel()
5. unpause both flush and compaction.

The major difference is that.  We only pause scheduling compaction in step 1 and wait
for all bg work finished in step 2.  This prevent flush being blocked for a long time.
Although there's a very rare case that ReFitLevel() might be in starvation in step 2,
but it's less likely the case as flush typically finish very fast.

Test Plan: existing test.

Reviewers: anthony, IslamAbdelRahman, kradhakrishnan, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D55029
2016-03-04 14:24:52 -08:00
Islam AbdelRahman
dfe96c72c3 Fix WriteLevel0TableForRecovery file delete protection
Summary:
The call to

```
CaptureCurrentFileNumberInPendingOutputs()
```

should be before

```
versions_->NewFileNumber()
```
Right now we are not actually protecting the file from being deleted

Test Plan: make check

Reviewers: sdong, anthony, yhchiang

Reviewed By: yhchiang

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D54645
2016-03-03 18:25:07 -08:00
sdong
e79ad9e184 Add Iterator Property rocksdb.iterator.version_number
Summary: We want to provide a way to detect whether an iterator is stale and needs to be recreated. Add a iterator property to return version number.

Test Plan: Add two unit tests for it.

Reviewers: IslamAbdelRahman, yhchiang, anthony, kradhakrishnan, andrewkr

Reviewed By: andrewkr

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D54921
2016-03-02 16:23:59 -08:00
Islam AbdelRahman
6743135ea1 Fix DB::AddFile() issue when PurgeObsoleteFiles() is called
Summary:
In some situations the DB will scan all existing files in the DB path and delete the ones that are Obsolete.
If this happen during adding an external sst file. this could cause the file to be deleted while we are adding it.
This diff fix this issue

Test Plan:
unit test to reproduce the bug
existing unit tests

Reviewers: sdong, yhchiang, andrewkr

Reviewed By: andrewkr

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D54627
2016-03-01 12:05:29 -08:00
sdong
38201b3599 Fix assert failure when DBImpl::SyncWAL() conflicts with log rolling
Summary: DBImpl::SyncWAL() releases db mutex before calling DBImpl::MarkLogsSynced(), while inside DBImpl::MarkLogsSynced() we assert there is none or one outstanding log file. However, a memtable switch can happen in between and causing two or outstanding logs there, failing the assert. The diff adds a unit test that repros the issue and fix the assert so that the unit test passes.

Test Plan: Run the new tests.

Reviewers: anthony, kolmike, yhchiang, IslamAbdelRahman, kradhakrishnan, andrewkr

Reviewed By: andrewkr

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D54621
2016-02-23 11:42:15 -08:00
Mike Kolupaev
eef63ef807 Fixed CompactFiles() spuriously failing or corrupting DB
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
2016-02-22 13:54:58 -08:00
Islam AbdelRahman
df9ba6df62 Introduce SstFileManager::SetMaxAllowedSpaceUsage() to cap disk space usage
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
2016-02-17 15:20:23 -08:00
reid horuff
5bcf952a87 Fix WriteImpl empty batch hanging issue
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
2016-02-16 12:21:33 -08:00
Mike Kolupaev
44371501f0 Fixed a segfault when compaction fails
Summary: We've hit it today.

Test Plan: `make -j check`; didn't reproduce the issue

Reviewers: yhchiang

Reviewed By: yhchiang

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D54219
2016-02-16 11:11:16 -08:00
Baraa Hamodi
21e95811d1 Updated all copyright headers to the new format. 2016-02-09 15:12:00 -08:00
Yueh-Hsuan Chiang
4a8cbf4e31 Allows Get and MultiGet to read directly from SST files.
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
2016-02-09 11:20:22 -08:00
reid horuff
6f71d3b68b Improve perf of Pessimistic Transaction expirations (and optimistic transactions)
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
2016-02-05 10:44:13 -08:00
Andrew Kryczka
284aa613a7 Eliminate duplicated property constants
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
2016-02-02 19:14:56 -08:00
Nathan Bronson
9c2cf9479b Fix for --allow_concurrent_memtable_write with batching
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
2016-02-01 20:41:57 -08:00
SherlockNoMad
37159a6448 Add histogram for value size per operation 2016-01-31 18:09:24 -08:00
Venkatesh Radhakrishnan
3b2a1ddd2e Add options.base_background_compactions as a number of compaction threads for low compaction debt
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
2016-01-29 16:15:53 -08:00
Islam AbdelRahman
d6c838f1e1 Add SstFileManager (component tracking all SST file in DBs and control the deletion rate)
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
2016-01-28 18:35:01 -08:00
Andrew Kryczka
167bd8856d [directory includes cleanup] Finish removing util->db dependencies 2016-01-26 10:49:24 -08:00
Andrew Kryczka
acd7d58695 [directory includes cleanup] Remove util->db dependency for ThreadStatusUtil
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
2016-01-26 10:49:16 -08:00
Andrew Kryczka
46f9cd46af [directory includes cleanup] Move cross-function test points
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
2016-01-26 10:49:05 -08:00
Islam AbdelRahman
2fbc59a348 Disallow SstFileWriter from creating empty sst files
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
2016-01-25 13:47:07 -08:00
David Bernard
3f12e16f27 Make alloca.h optional 2016-01-19 06:17:31 +00:00
David Bernard
d78c6b28c4 Changes for build on solaris
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
2016-01-19 04:45:21 +00:00
Venkatesh Radhakrishnan
7ece10ecb6 DeleteFilesInRange: Mark files to be deleted as being compacted before applying change
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
2016-01-07 14:48:45 -08:00
Reid Horuff
da032495d3 Optimize GetLatestSequenceForKey
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
2016-01-06 13:43:22 -08:00
Venkatesh Radhakrishnan
d74c9f0a57 DeleteFilesInRange: Clean job context if no files deleted
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
2016-01-04 10:55:31 -08:00
Nathan Bronson
ac16663bd6 use -Werror=missing-field-initializers, to closer match MyRocks build
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
2015-12-30 14:56:18 -08:00
Venkatesh Radhakrishnan
63ddb783db Delete files in given key range
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
2015-12-29 13:22:13 -08:00
Siying Dong
22c0ed8a5f Disable Visual Studio Warning C4351
Currently Windows build is broken because of Warning C4351. Disable the warning before figuring out the right way to fix it.
2015-12-28 15:06:34 -08:00
sdong
11672df19a Fix CLANG errors introduced by 7d87f02799
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
2015-12-28 10:00:58 -08:00
Nathan Bronson
7d87f02799 support for concurrent adds to memtable
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
2015-12-25 11:03:40 -08:00
Siying Dong
298ba27ae2 Merge pull request #846 from yuslepukhin/enble_c4244_lossofdata
Enable MS compiler warning c4244.
2015-12-23 22:59:42 -08:00
Islam AbdelRahman
d005c66faf Report compaction reason in CompactionListener
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
2015-12-22 11:37:19 -08:00
Alex Yang
33e09c0e19 add call to install superversion and schedule work in enableautocompactions
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
2015-12-21 10:06:49 -08:00
Venkatesh Radhakrishnan
7b12ae97d4 Add signalall after removing item from manual_compaction deque
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
2015-12-17 16:59:00 -08:00
Islam AbdelRahman
aececc209e Introduce ReadOptions::pin_data (support zero copy for keys)
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
2015-12-16 12:08:30 -08:00
Gunnar Kudrjavets
97265f5f14 Fix minor bugs in delete operator, snprintf, and size_t usage
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
2015-12-15 15:26:20 -08:00
Venkatesh Radhakrishnan
030215bf01 Running manual compactions in parallel with other automatic or manual compactions in restricted cases
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
2015-12-14 11:20:34 -08:00