Commit Graph

159 Commits

Author SHA1 Message Date
Siying Dong
52a7f38b19 WriteOptions.low_pri which can throttle low pri writes if needed
Summary:
If ReadOptions.low_pri=true and compaction is behind, the write will either return immediate or be slowed down based on ReadOptions.no_slowdown.
Closes https://github.com/facebook/rocksdb/pull/2369

Differential Revision: D5127619

Pulled By: siying

fbshipit-source-id: d30e1cff515890af0eff32dfb869d2e4c9545eb0
2017-06-05 15:02:35 -07:00
hyunwoo
c7662a44a4 fixed typo
Summary:
fixed typo
Closes https://github.com/facebook/rocksdb/pull/2376

Differential Revision: D5183630

Pulled By: ajkr

fbshipit-source-id: 133cfd0445959e70aa2cd1a12151bf3c0c5c3ac5
2017-06-05 11:27:34 -07:00
Andrew Kryczka
a4d9c02511 Pass CF ID to MemTableRepFactory
Summary:
Some users want to monitor column family activity in their custom memtable implementations. Previously there was no way to figure out with which column family a memtable is associated. This diff:

- adds an overload to MemTableRepFactory::CreateMemTableRep() that provides the CF ID. For compatibility, its default implementation calls the old overload.
- updates MemTable to create MemTableRep's using the new overload.
Closes https://github.com/facebook/rocksdb/pull/2346

Differential Revision: D5108061

Pulled By: ajkr

fbshipit-source-id: 3a1921214a348dd8ea0f54e1cab3b71c3d46d616
2017-06-02 12:12:06 -07:00
Sagar Vemuri
7bb1f5d483 Increase of compaction threads should be logged at info level instead of a warning
Summary:
This log message shouldn't be a warning; some services are seeing high warning count due to this.

The count for the below line is a few hundreds of millions, as per Logview:
```
[rocksdb/src/db/column_family.cc:729] [checkpoints] Increasing compaction threads because we have 2 level-0 files
```
Closes https://github.com/facebook/rocksdb/pull/2364

Differential Revision: D5123565

Pulled By: sagar0

fbshipit-source-id: a07ce499a4f82f0ebde9cda9f4948fb9df6a734c
2017-05-26 09:56:13 -07:00
Mikhail Antonov
ba685a472a Support ingest_behind for IngestExternalFile
Summary:
First cut for early review; there are few conceptual points to answer and some code structure issues.

For conceptual points -

 - restriction-wise, we're going to disallow ingest_behind if (use_seqno_zero_out=true || disable_auto_compaction=false), the user is responsible to properly open and close DB with required params
 - we wanted to ingest into reserved bottom most level. Should we fail fast if bottom level isn't empty, or should we attempt to ingest if file fits there key-ranges-wise?
 - Modifying AssignLevelForIngestedFile seems the place we we'd handle that.

On code structure - going to refactor GenerateAndAddExternalFile call in the test class to allow passing instance of IngestionOptions, that's just going to incur lots of changes at callsites.
Closes https://github.com/facebook/rocksdb/pull/2144

Differential Revision: D4873732

Pulled By: lightmark

fbshipit-source-id: 81cb698106b68ef8797f564453651d50900e153a
2017-05-17 11:42:42 -07:00
Siying Dong
264d3f540c Allow IntraL0 compaction in FIFO Compaction
Summary:
Allow an option for users to do some compaction in FIFO compaction, to pay some write amplification for fewer number of files.
Closes https://github.com/facebook/rocksdb/pull/2163

Differential Revision: D4895953

Pulled By: siying

fbshipit-source-id: a1ab608dd0627211f3e1f588a2e97159646e1231
2017-05-04 18:16:13 -07:00
Siying Dong
aeaba07b2a Remove an assert that causes TSAN failure.
Summary:
ColumnFamilyData::ConstructNewMemtable is called out of DB mutex, and it asserts current_ is not empty, but current_ should only be accessed inside DB mutex. Remove this assert to make TSAN happy.
Closes https://github.com/facebook/rocksdb/pull/2235

Differential Revision: D4978531

Pulled By: siying

fbshipit-source-id: 423685a7dae88ed3faaa9e1b9ccb3427ac704a4b
2017-05-01 16:35:15 -07:00
Siying Dong
d616ebea23 Add GPLv2 as an alternative license.
Summary: Closes https://github.com/facebook/rocksdb/pull/2226

Differential Revision: D4967547

Pulled By: siying

fbshipit-source-id: dd3b58ae1e7a106ab6bb6f37ab5c88575b125ab4
2017-04-27 18:06:12 -07:00
Siying Dong
ff97287016 Refactor compaction picker code
Summary:
1. Move universal compaction picker to separate files compaction_picker_universal.cc and compaction_picker_universal.h.
2. Rename some functions to make the code easier to understand.
3. Move leveled compaction picking code to a dedicated class, so that we we don't need to pass some common variable around when calling functions. It also allowed us to break down LevelCompactionPicker::PickCompaction() to smaller functions.
Closes https://github.com/facebook/rocksdb/pull/2100

Differential Revision: D4845948

Pulled By: siying

fbshipit-source-id: efa0ab4
2017-04-06 20:09:34 -07:00
Siying Dong
d2dce5611a Move some files under util/ to separate dirs
Summary:
Move some files under util/ to new directories env/, monitoring/ options/ and cache/
Closes https://github.com/facebook/rocksdb/pull/2090

Differential Revision: D4833681

Pulled By: siying

fbshipit-source-id: 2fd8bef
2017-04-05 19:09:16 -07:00
Islam AbdelRahman
e19163688b Add macros to include file name and line number during Logging
Summary:
current logging
```
2017/03/14-14:20:30.393432 7fedde9f5700 (Original Log Time 2017/03/14-14:20:30.393414) [default] Level summary: base level 1 max bytes base 268435456 files[1 0 0 0 0 0 0] max score 0.25
2017/03/14-14:20:30.393438 7fedde9f5700 [JOB 2] Try to delete WAL files size 61417909, prev total WAL file size 73820858, number of live WAL files 2.
2017/03/14-14:20:30.393464 7fedde9f5700 [DEBUG] [JOB 2] Delete /dev/shm/old_logging//MANIFEST-000001 type=3 #1 -- OK
2017/03/14-14:20:30.393472 7fedde9f5700 [DEBUG] [JOB 2] Delete /dev/shm/old_logging//000003.log type=0 #3 -- OK
2017/03/14-14:20:31.427103 7fedd49f1700 [default] New memtable created with log file: #9. Immutable memtables: 0.
2017/03/14-14:20:31.427179 7fedde9f5700 [JOB 3] Syncing log #6
2017/03/14-14:20:31.427190 7fedde9f5700 (Original Log Time 2017/03/14-14:20:31.427170) Calling FlushMemTableToOutputFile with column family [default], flush slots available 1, compaction slots allowed 1, compaction slots scheduled 1
2017/03/14-14:20:31.
Closes https://github.com/facebook/rocksdb/pull/1990

Differential Revision: D4708695

Pulled By: IslamAbdelRahman

fbshipit-source-id: cb8968f
2017-03-15 19:39:12 -07:00
Siying Dong
1ba2804b7f Remove XFunc tests
Summary:
Xfunc is hardly used. Remove it to keep the code simple.
Closes https://github.com/facebook/rocksdb/pull/1905

Differential Revision: D4603220

Pulled By: siying

fbshipit-source-id: 731f96d
2017-02-23 12:09:11 -08:00
Reid Horuff
5cf176ca15 Fix for 2PC causing WAL to grow too large
Summary:
Consider the following single column family scenario:
prepare in log A
commit in log B
*WAL is too large, flush all CFs to releast log A*
*CFA is on log B so we do not see CFA is depending on log A so no flush is requested*

To fix this we must also consider the log containing the prepare section when determining what log a CF is dependent on.
Closes https://github.com/facebook/rocksdb/pull/1768

Differential Revision: D4403265

Pulled By: reidHoruff

fbshipit-source-id: ce800ff
2017-01-19 15:39:12 -08:00
Islam AbdelRahman
3c6b49ed66 Fix implicit conversion between int64_t to int
Summary:
Make conversion explicit, implicit conversion breaks the build
Closes https://github.com/facebook/rocksdb/pull/1589

Differential Revision: D4245158

Pulled By: IslamAbdelRahman

fbshipit-source-id: aaec00d
2016-11-29 10:54:15 -08:00
Islam AbdelRahman
a2bf265a39 Avoid intentional overflow in GetL0ThresholdSpeedupCompaction
Summary:
99c052a34f fixes integer overflow in GetL0ThresholdSpeedupCompaction() by checking if int become -ve.
UBSAN will complain about that since this is still an overflow, we can fix the issue by simply using int64_t
Closes https://github.com/facebook/rocksdb/pull/1582

Differential Revision: D4241525

Pulled By: IslamAbdelRahman

fbshipit-source-id: b3ae21f
2016-11-28 18:39:13 -08:00
Siying Dong
cd7c4143d7 Improve Write Stalling System
Summary:
Current write stalling system has the problem of lacking of positive feedback if the restricted rate is already too low. Users sometimes stack in very low slowdown value. With the diff, we add a positive feedback (increasing the slowdown value) if we recover from slowdown state back to normal. To avoid the positive feedback to keep the slowdown value to be to high, we add issue a negative feedback every time we are close to the stop condition. Experiments show it is easier to reach a relative balance than before.

Also increase level0_stop_writes_trigger default from 24 to 32. Since level0_slowdown_writes_trigger default is 20, stop trigger 24 only gives four files as the buffer time to slowdown writes. In order to avoid stop in four files while 20 files have been accumulated, the slowdown value must be very low, which is amost the same as stop. It also doesn't give enough time for the slowdown value to converge. Increase it to 32 will smooth out the system.
Closes https://github.com/facebook/rocksdb/pull/1562

Differential Revision: D4218519

Pulled By: siying

fbshipit-source-id: 95e4088
2016-11-23 09:24:15 -08:00
Yi Wu
dfb6fe6755 Unified InlineSkipList::Insert algorithm with hinting
Summary:
This PR is based on nbronson's diff with small
modifications to wire it up with existing interface. Comparing to
previous version, this approach works better for inserting keys in
decreasing order or updating the same key, and impose less restriction
to the prefix extractor.

---- Summary from original diff ----

This diff introduces a single InlineSkipList::Insert that unifies
the existing sequential insert optimization (prev_), concurrent insertion,
and insertion using externally-managed insertion point hints.

There's a deep symmetry between insertion hints (cursors) and the
concurrent algorithm.  In both cases we have partial information from
the recent past that is likely but not certain to be accurate.  This diff
introduces the struct InlineSkipList::Splice, which encodes predecessor
and successor information in the same form that was previously only used
within a single call to InsertConcurrently.  Splice holds information
about an insertion point that can be used to levera
Closes https://github.com/facebook/rocksdb/pull/1561

Differential Revision: D4217283

Pulled By: yiwu-arbug

fbshipit-source-id: 33ee437
2016-11-22 14:09:13 -08:00
Andrew Kryczka
661e4c9267 DeleteRange unsupported in non-block-based tables
Summary:
Return an error from DeleteRange() (or Write() if the user is using the
low-level WriteBatch API) if an unsupported table type is configured.
Closes https://github.com/facebook/rocksdb/pull/1519

Differential Revision: D4185933

Pulled By: ajkr

fbshipit-source-id: abcdf84
2016-11-15 15:24:16 -08:00
Islam AbdelRahman
eba99c28e4 Fix min_write_buffer_number_to_merge = 0 bug
Summary:
It's possible that we set min_write_buffer_number_to_merge to 0.
This should never happen
Closes https://github.com/facebook/rocksdb/pull/1515

Differential Revision: D4183356

Pulled By: yiwu-arbug

fbshipit-source-id: c9d39d7
2016-11-15 13:54:08 -08:00
Yi Wu
1ea79a78c9 Optimize sequential insert into memtable - Part 1: Interface
Summary:
Currently our skip-list have an optimization to speedup sequential
inserts from a single stream, by remembering the last insert position.
We extend the idea to support sequential inserts from multiple streams,
and even tolerate small reordering wihtin each stream.

This PR is the interface part adding the following:
- Add `memtable_insert_prefix_extractor` to allow specifying prefix for each key.
- Add `InsertWithHint()` interface to memtable, to allow underlying
  implementation to return a hint of insert position, which can be later
  pass back to optimize inserts.
- Memtable will maintain a map from prefix to hints and pass the hint
  via `InsertWithHint()` if `memtable_insert_prefix_extractor` is non-null.
Closes https://github.com/facebook/rocksdb/pull/1419

Differential Revision: D4079367

Pulled By: yiwu-arbug

fbshipit-source-id: 3555326
2016-11-13 19:09:18 -08:00
Lijun Tang
adb665e0bf Allowed delayed_write_rate option to be dynamically set.
Summary: Closes https://github.com/facebook/rocksdb/pull/1488

Differential Revision: D4157784

Pulled By: siying

fbshipit-source-id: f150081
2016-11-12 15:54:11 -08:00
Edouard A
99c052a34f Fix integer overflow in GetL0ThresholdSpeedupCompaction (#1378) 2016-10-23 18:43:29 -07:00
Aaron Gao
59a7c0337b Change ioptions to store user_comparator, fix bug
Summary:
change ioptions.comparator to user_comparator instread of internal_comparator.
Also change Comparator* to InternalKeyComparator* to make its type explicitly.

Test Plan: make all check -j64

Reviewers: andrewkr, sdong, yiwu

Reviewed By: yiwu

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D65121
2016-10-21 11:31:42 -07:00
Islam AbdelRahman
5691a1d8a4 Fix compaction conflict with running compaction
Summary:
Issue scenario:
(1) We have 3 files in L1 and we issue a compaction that will compact them into 1 file in L2
(2) While compaction (1) is running, we flush a file into L0 and trigger another compaction that decide to move this file to L1 and then move it again to L2 (this file don't overlap with any other files)
(3) compaction (1) finishes and install the file it generated in L2, but this file overlap with the file we generated in (2) so we break the LSM consistency

Looks like this issue can be triggered by using non-exclusive manual compaction or AddFile()

Test Plan: unit tests

Reviewers: sdong

Reviewed By: sdong

Subscribers: hermanlee4, jkedgar, andrewkr, dhruba, yoshinorim

Differential Revision: https://reviews.facebook.net/D64947
2016-10-13 10:49:06 -07:00
Yi Wu
9ed928e7a9 Split DBOptions into ImmutableDBOptions and MutableDBOptions
Summary: Use ImmutableDBOptions/MutableDBOptions internally and DBOptions only for user-facing APIs. MutableDBOptions is barely a placeholder for now. I'll start to move options to MutableDBOptions in following diffs.

Test Plan:
  make all check

Reviewers: yhchiang, IslamAbdelRahman, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D64065
2016-09-23 16:34:04 -07:00
Aaron Gao
0a1bd9c509 add cfh deletion started listener
Summary: add ColumnFamilyHandleDeletionStarted listener which can be called when user deletes handler.

Test Plan: ./listener_test

Reviewers: yiwu, IslamAbdelRahman, sdong, andrewkr

Reviewed By: andrewkr

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D60717
2016-09-22 11:56:18 -07:00
Yi Wu
0a88f38b7e Remove ColumnFamilyData::options()
Summary: One more small refactor before I split DBOptions into mutable and immutable parts.

Test Plan: existing unit tests.

Reviewers: yhchiang, IslamAbdelRahman, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D64047
2016-09-16 15:09:14 -07:00
Yi Wu
17f76fc564 DB::GetOptions() reflect dynamic changed options
Summary: DB::GetOptions() reflect dynamic changed options.

Test Plan: See the new unit test.

Reviewers: yhchiang, sdong, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D63903
2016-09-14 22:10:28 -07:00
Yi Wu
81747f1be6 Refactor MutableCFOptions
Summary:
* Change constructor of MutableCFOptions to depends only on ColumnFamilyOptions.
* Move `max_subcompactions`, `compaction_options_fifo` and `compaction_pri` to ImmutableCFOptions to make it clear that they are immutable.

Test Plan: existing unit tests.

Reviewers: yhchiang, IslamAbdelRahman, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D63945
2016-09-13 21:11:59 -07:00
sdong
32149059f9 Merge options source_compaction_factor, max_grandparent_overlap_bytes and expanded_compaction_factor into max_compaction_bytes
Summary: To reduce number of options, merge source_compaction_factor, max_grandparent_overlap_bytes and expanded_compaction_factor into max_compaction_bytes.

Test Plan: Add two new unit tests. Run all existing tests, including jtest.

Reviewers: yhchiang, igor, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D59829
2016-09-01 14:33:24 -07:00
Yi Wu
ee027fc19f Ignore write stall triggers when auto-compaction is disabled
Summary:
My understanding is that the purpose of write stall triggers are to wait for auto-compaction to catch up. Without auto-compaction, we don't need to stall writes.

Also with this diff, flush/compaction conditions are recalculated on dynamic option change. Previously the conditions are recalculate only when write stall options are changed.

Test Plan: See the new test. Removed two tests that are no longer valid.

Reviewers: IslamAbdelRahman, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D61437
2016-08-02 21:55:26 -07:00
Jay Edgar
cdc4eb6892 Add a GetComparator() function to the ColumnFamilyHandle base class so that the user's comparator can be retrieved.
Summary: MyRocks is adding support for the user of the SstFileWriter which needs a comparator.  It would be more convenient to get the comparator from the column family (which already has to have it) than to have caller keep track of it.

Test Plan: Standard tests (adding one for the new method)

Reviewers: IslamAbdelRahman, sdong

Reviewed By: sdong

Subscribers: andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D61155
2016-08-02 14:34:57 -07:00
sdong
32df9733d1 Add options.write_buffer_manager: control total memtable size across DB instances
Summary: Add option write_buffer_manager to help users control total memory spent on memtables across multiple DB instances.

Test Plan: Add a new unit test.

Reviewers: yhchiang, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: adela, benj, sumeet, muthu, leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D59925
2016-07-05 18:11:25 -07:00
sdong
7b79238b65 Deprectate filter_deletes
Summary: filter_deltes is not a frequently used feature. Remove it.

Test Plan: Run all test suites.

Reviewers: igor, yhchiang, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D59427
2016-06-17 10:30:47 -07:00
sdong
20699df843 memtable_prefix_bloom_bits -> memtable_prefix_bloom_bits_ratio and deprecate memtable_prefix_bloom_probes
Summary:
memtable_prefix_bloom_probes is not a critical option. Remove it to reduce number of options.
It's easier for users to make mistakes with memtable_prefix_bloom_bits, turn it to memtable_prefix_bloom_bits_ratio

Test Plan: Run all existing tests

Reviewers: yhchiang, igor, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: gunnarku, yoshinorim, MarkCallaghan, leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D59199
2016-06-10 12:12:10 -07:00
Warren Falk
b8cf9130f8 Fix #1110, 32-bit build failure on Mac OSX (#1112)
Using explicit 64-bit type in conditional in platforms above 32-bits
This appears to be necessary on Mac OSX as std::conditional does not appear to short circuit and evaluates the third template arg
Making the third template arg be 64 bits explicitly works around this problem and will work on both 32 bit and 64+ bit platforms.
2016-05-02 10:04:37 -07:00
Dhruba Borthakur
1a2cc27e01 ColumnFamilyOptions SanitizeOptions is buggy on 32-bit platforms.
Summary:
The pre-existing code is trying to clamp between 65,536 and 0,
resulting in clamping to 65,536, resulting in very small buffers,
resulting in ShouldFlushNow() being true quite easily,
resulting in assertion failing and database performance
being "not what it should be".

https://github.com/facebook/rocksdb/issues/1018

Test Plan: make check

Reviewers: sdong, andrewkr, IslamAbdelRahman, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D55455
2016-03-14 16:21:54 -07:00
Baraa Hamodi
21e95811d1 Updated all copyright headers to the new format. 2016-02-09 15:12:00 -08:00
sdong
b1887c5dd9 Explictly fail when memtable doesn't support concurrent insert
Summary: If users turn on concurrent insert but the memtable doesn't support it, they might see unexcepted crash. Fix it by explicitly fail.

Test Plan:
Run different setting of stress_test and make sure it fails correctly.
Will add a unit test too.

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

Reviewed By: ngbronson

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D53895
2016-02-05 14:15:50 -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
sdong
6ee38bb15c Slowdown of writing to the last memtable should not override stopping
Summary: Now slowing down for the last mem table takes priority against some stopping conditions. This is logically confusing. Fix it.

Test Plan: Run all existing tests.

Reviewers: yhchiang, IslamAbdelRahman, kradhakrishnan, andrewkr, anthony

Reviewed By: anthony

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D53529
2016-01-28 21:52:29 -08:00
Yueh-Hsuan Chiang
6935eb24e0 Add ColumnFamilyHandle::GetDescriptor()
Summary:
This patch addes ColumnFamilyHandle::GetDescriptor(), which allows
developers to obtain the CF options and names of the associated column
family given its handle.

  // Returns the up-to-date descriptor used by the current handle.  Since it
  // returns the up-to-date information, this call might internally locks
  // and releases DB mutex to access the up-to-date CF options.
  virtual ColumnFamilyDescriptor GetDescriptor() = 0;

Test Plan: augment column_family_test

Reviewers: sdong, yoshinorim, IslamAbdelRahman, rven, kradhakrishnan, anthony

Reviewed By: anthony

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D51543
2016-01-06 18:14:01 -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
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
sdong
b9f77ba12b When slowdown is triggered, reduce the write rate
Summary: It's usually hard for users to set a value of options.delayed_write_rate. With this diff, after slowdown condition triggers, we greedily reduce write rate if estimated pending compaction bytes increase. If estimated compaction pending bytes drop, we increase the write rate.

Test Plan:
Add a unit test
Test with db_bench setting:
TEST_TMPDIR=/dev/shm/ ./db_bench --benchmarks=fillrandom -num=10000000 --soft_pending_compaction_bytes_limit=1000000000 --hard_pending_compaction_bytes_limit=3000000000 --delayed_write_rate=100000000

and make sure without the commit, write stop will happen, but with the commit, it will not happen.

Reviewers: igor, anthony, rven, yhchiang, kradhakrishnan, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D52131
2015-12-23 11:33:15 -08:00
sdong
d72b31774e Slowdown when writing to the last write buffer
Summary: Now if inserting to mem table is much faster than writing to files, there is no mechanism users can rely on to avoid stopping for reaching options.max_write_buffer_number. With the commit, if there are more than four maximum write buffers configured, we slow down to the rate of options.delayed_write_rate while we reach the last one.

Test Plan:
1. Add a new unit test.
2. Run db_bench with

./db_bench --benchmarks=fillrandom --num=10000000 --max_background_flushes=6 --batch_size=32 -max_write_buffer_number=4 --delayed_write_rate=500000 --statistics

based on hard drive and see stopping is avoided with the commit.

Reviewers: yhchiang, IslamAbdelRahman, anthony, rven, kradhakrishnan, igor

Reviewed By: igor

Subscribers: MarkCallaghan, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D52047
2015-12-17 10:49:08 -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
sdong
56e77f0967 Deprecate options.soft_rate_limit and add options.soft_pending_compaction_bytes_limit
Summary: Deprecate options.soft_rate_limit, which is hard to tune, with options.soft_pending_compaction_bytes_limit, which would trigger the slowdown if estimated pending compaction bytes exceeds the threshold. The hope is to make it more striaght-forward to tune.

Test Plan: Modify DBTest.SoftLimit to cover options.soft_pending_compaction_bytes_limit instead; run all unit tests.

Reviewers: IslamAbdelRahman, yhchiang, rven, kradhakrishnan, igor, anthony

Reviewed By: anthony

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D51117
2015-12-09 18:22:45 -08:00
sdong
dac5b248b1 UniversalCompactionPicker::PickCompaction(): avoid to form compactions if there is no file
Summary:
Currently RocksDB may break in lines like this:

for (size_t i = sorted_runs.size() - 1; i >= first_index_after; i--) {

if options.level0_file_num_compaction_trigger=0.

Fix it by not executing the logic of picking compactions if there is no file (sorted_runs.size() = 0). Also internally set options.level0_file_num_compaction_trigger=1 if users give a 0. 0 is a value makes no sense in RocksDB.

Test Plan: Run all tests. Will add a unit test too.

Reviewers: yhchiang, IslamAbdelRahman, anthony, kradhakrishnan, rven

Reviewed By: rven

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D50727
2015-11-16 10:32:45 -08:00
Venkatesh Radhakrishnan
a98fbacfa0 Moving memtable related files from util to a new directory memtable
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
2015-10-16 14:10:33 -07:00