Commit Graph

20 Commits

Author SHA1 Message Date
sdong
f1b9f804e9 Add a mode to always pick the oldest file to compact for each level
Summary:
Add options.compaction_pri, which specifies the policy about which file to compact first.
kCompactionPriByLargestSeq will compact oldest files first.
Verified the behavior in db_bench but did not write unit tests yet. Also need to make it settable through option string and dynamically changeable.

Test Plan: Will write unit tests

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

Reviewed By: yhchiang

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D45951
2015-09-21 17:21:59 -07:00
sdong
5de807ac16 Add options.hard_pending_compaction_bytes_limit to stop writes if compaction lagging behind
Summary: Add an option to stop writes if compaction lefts behind. If estimated pending compaction bytes is more than threshold specified by options.hard_pending_compaction_bytes_liimt, writes will stop until compactions are cleared to under the threshold.

Test Plan: Add unit test DBTest.HardLimit

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

Reviewed By: igor

Subscribers: MarkCallaghan, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D45999
2015-09-14 12:51:16 -07:00
Ari Ekmekji
b6def58f73 Changed 'num_subcompactions' to the more accurate 'max_subcompactions'
Summary:
Up until this point we had DbOptions.num_subcompactions, but
it is semantically more correct to call this max_subcompactions since
we will schedule *up to* DbOptions.max_subcompactions smaller compactions
at a time during a compaction job.

I also added a --subcompactions option to db_bench

Test Plan: make all   make check

Reviewers: sdong, igor, anthony, yhchiang

Reviewed By: yhchiang

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D45069
2015-08-21 14:25:34 -07:00
sdong
603b6da8b8 Add options.compaction_measure_io_stats to print write I/O stats in compactions
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
2015-08-13 16:52:26 -07:00
Ari Ekmekji
40c64434d4 Parallelize L0-L1 Compaction: Restructure Compaction Job
Summary:
As of now compactions involving files from Level 0 and Level 1 are single
threaded because the files in L0, although sorted, are not range partitioned like
the other levels. This means that during L0-L1 compaction each file from L1
needs to be merged with potentially all the files from L0.

This attempt to parallelize the L0-L1 compaction assigns a thread and a
corresponding iterator to each L1 file that then considers only the key range
found in that L1 file and only the L0 files that have those keys (and only the
specific portion of those L0 files in which those keys are found). In this way
the overlap is minimized and potentially eliminated between different iterators
focusing on the same files.

The first step is to restructure the compaction logic to break L0-L1 compactions
into multiple, smaller, sequential compactions. Eventually each of these smaller
jobs will be run simultaneously. Areas to pay extra attention to are

  # Correct aggregation of compaction job statistics across multiple threads
  # Proper opening/closing of output files (make sure each thread's is unique)
  # Keys that span multiple L1 files
  # Skewed distributions of keys within L0 files

Test Plan: Make and run db_test (newer version has separate compaction tests) and compaction_job_stats_test

Reviewers: igor, noetzli, anthony, sdong, yhchiang

Reviewed By: yhchiang

Subscribers: MarkCallaghan, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D42699
2015-08-03 11:32:14 -07:00
Igor Canadi
35ca59364c Don't let flushes preempt compactions
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
2015-07-17 12:02:52 -07:00
sdong
397b6588bd options.paranoid_file_checks to read all rows after writing to a file.
Summary: To further distinguish the corruption cases were caused by storage media or in memory states when writing it, add a paranoid check after writing the file to iterate all the rows.

Test Plan: Add a new unit test for it

Reviewers: rven, igor

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D37335
2015-04-23 11:34:35 -07:00
sdong
b23bbaa82a Universal Compactions with Small Files
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
2015-03-30 15:12:02 -07:00
Igor Canadi
db03739340 options.level_compaction_dynamic_level_bytes to allow RocksDB to pick size bases of levels dynamically.
Summary:
When having fixed max_bytes_for_level_base, the ratio of size of largest level and the second one can range from 0 to the multiplier. This makes LSM tree frequently irregular and unpredictable. It can also cause poor space amplification in some cases.

In this improvement (proposed by Igor Kabiljo), we introduce a parameter option.level_compaction_use_dynamic_max_bytes. When turning it on, RocksDB is free to pick a level base in the range of (options.max_bytes_for_level_base/options.max_bytes_for_level_multiplier, options.max_bytes_for_level_base] so that real level ratios are close to options.max_bytes_for_level_multiplier.

Test Plan: New unit tests and pass tests suites including valgrind.

Reviewers: MarkCallaghan, rven, yhchiang, igor, ikabiljo

Reviewed By: ikabiljo

Subscribers: yoshinorim, ikabiljo, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D31437
2015-03-02 22:40:41 -08:00
Lei Jin
8d3f8f9696 remove all remaining references to cfd->options()
Summary:
The very last reference happens in DBImpl::GetOptions()
I built with both DBImpl::GetOptions() and ColumnFamilyData::options() commented out

Test Plan: make all check

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D29073
2014-11-18 10:20:10 -08:00
Igor Canadi
767777c2bd Turn on -Wshorten-64-to-32 and fix all the errors
Summary:
We need to turn on -Wshorten-64-to-32 for mobile. See D1671432 (internal phabricator) for details.

This diff turns on the warning flag and fixes all the errors. There were also some interesting errors that I might call bugs, especially in plain table. Going forward, I think it makes sense to have this flag turned on and be very very careful when converting 64-bit to 32-bit variables.

Test Plan: compiles

Reviewers: ljin, rven, yhchiang, sdong

Reviewed By: yhchiang

Subscribers: bobbaldwin, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D28689
2014-11-11 16:47:22 -05:00
Lei Jin
f1841985e4 dynamic inplace_update options
Summary:
Make inplace_update_support and inplace_update_num_locks dynamic.
inplace_callback becomes immutable
We are almost free of references to cfd->options() in db_impl

Test Plan: unit test

Reviewers: igor, yhchiang, rven, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D25293
2014-10-27 12:10:13 -07:00
Lei Jin
122f98e0b9 dynamic max_mem_compact_level
Summary: as title

Test Plan: unit test

Reviewers: sdong, yhchiang, rven, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D25347
2014-10-23 15:37:14 -07:00
Lei Jin
574028679b dynamic max_sequential_skip_in_iterations
Summary:
This is not a critical options. Making it dynamic so that we can remove
more reference to cfd->options()

Test Plan: unit test

Reviewers: yhchiang, sdong, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D24957
2014-10-23 15:34:21 -07:00
Lei Jin
d6c8dba727 Log MutableCFOptions in SetOptions
Summary: as title

Test Plan: make release

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D24903
2014-10-16 17:22:28 -07:00
Lei Jin
4d5708aa56 dynamic soft_rate_limit and hard_rate_limit
Summary: as title

Test Plan:
unit test
I am only able to build the test case for hard_rate_limit.
soft_rate_limit is essentially the same thing as hard_rate_limit

Reviewers: igor, sdong, yhchiang

Reviewed By: yhchiang

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D24759
2014-10-16 17:21:31 -07:00
Lei Jin
065a67c4f0 dynamic disable_auto_compactions
Summary: Add more tests as well

Test Plan: unit test

Reviewers: igor, sdong, yhchiang

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D24747
2014-10-16 17:14:17 -07:00
Lei Jin
dc50a1a593 make max_write_buffer_number dynamic
Summary: as title

Test Plan: unit test

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D24729
2014-10-16 16:57:59 -07:00
Lei Jin
5ec53f3edf make compaction related options changeable
Summary:
make compaction related options changeable. Most of changes are tedious,
following the same convention: grabs MutableCFOptions at the beginning
of compaction under mutex, then pass it throughout the job and register
it in SuperVersion at the end.

Test Plan: make all check

Reviewers: igor, yhchiang, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23349
2014-10-01 16:19:16 -07:00
Lei Jin
a062e1f2c4 SetOptions() for memtable related options
Summary: as title

Test Plan:
make all check
I will think a way to set up stress test for this

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23055
2014-09-17 12:49:13 -07:00