Summary:
Implement a benchmark for universal compaction based on the feature description (see below), in-person discussions, and reading source code:
https://github.com/facebook/rocksdb/wiki/RocksDB-Tuning-Guidehttps://github.com/facebook/rocksdb/wiki/Universal-Compactionhttps://github.com/facebook/rocksdb/wiki/RocksDB-Tuning-Guide#universal-compaction
Universal compaction benchmark is based on `overwrite` benchmark, adding compaction specific options to it, and executing it for different values of subcompaction to understand the impact of scaling out subcompactions for a particular scenario.
Test Plan:
- Execute the benchmark on various machines for multiple iterations to verify the reliability.
- Observe the output to make sure that compaction is taking place.
- Observe the execution to make sure that arguments passed to `db_bench` are correct.
Reviewers: sdong, MarkCallaghan
Reviewed By: MarkCallaghan
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D54045
Summary: This set of changes is part of the work to introduce benchmark for universal style compaction in RocksDB. It's conceptually separate from the compaction work, so sending it out as a separate diff to get it out of the way.
Test Plan:
- Run `./tools/run_flash_bench.sh`.
- Look at the contents of `report.txt` and `report2.txt` to make sure that data is reported and attributed correctly.
- During `db_bench` execution time make sure that the correct flags are passed to `--disable_wal` depending on the benchmark being executed.
Reviewers: MarkCallaghan
Reviewed By: MarkCallaghan
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D53865
Summary:
1) changes tools/{benchmark,run_flash_bench}.sh to optionally use the write rate limit
2) removes code for --writes_per_second and switches the 'background' write rate limit
to use --benchmark_write_rate_limit
Replaces https://reviews.facebook.net/D49113
Task ID: #9555881
Blame Rev:
Test Plan:
tools/run_flash_bench.sh
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Database Impact:
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- begin *PUBLIC* platform impact section -
Bugzilla: #
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Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D52485
Summary:
db_bench output now displays Percentile many times with --statistics after
read IO latency histograms were added. So I only need the last one in the report output.
Task ID: #
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Test Plan:
run run_flash_bench.sh
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- begin *PUBLIC* platform impact section -
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Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D45093
Summary:
Changes include:
* don't sync-on-commit for single writer thread in readwhile... tests
* make default block size 8kb rather than 4kb to avoid too small blocks after compression
* use snappy instead of zlib to avoid stalls from compression latency
* disable statistics
* use bytes_per_sync=8M to reduce throughput loss on disk
* use open_files=-1 to reduce mutex contention
Task ID: #
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Test Plan:
run benchmark
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Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D44961
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:
This is done to avoid having each thread use the same seed between runs
of db_bench. Without this we can inflate the OS filesystem cache hit rate on
reads for read heavy tests and generally see the same key sequences get generated
between teste runs.
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Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D37563
Summary:
This adds:
1) use of --level_compaction_dynamic_level_bytes=true
2) use of --bytes_per_sync=2M
The second is a big win for disks. The first helps in general.
This also adds a new test, fillseq with 32kb values to increase the peak
ingest and make it more likely that storage limits throughput.
Sample outpout from the first 3 tests - https://gist.github.com/mdcallag/e793bd3038e367b05d6f
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Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D37509
Summary:
This changes loads to use vector memtable and disable the WAL. This also
increases the chance we will see IO bottlenecks during loads which is good to stress
test HW. But I also think it is a good way to load data quickly as this is a bulk
operation and the WAL isn't needed.
The two numbers below are the MB/sec rates for fillseq, bulkload using a skiplist
or vector memtable and the WAL enabled or disabled. There is a big benefit from
using the vector memtable and WAL disabled. Alas there is also a perf bug in
the use of std::sort for ordered input when the vector is flushed. Task is open
for that.
112, 66 - skiplist with wal
250, 116 - skiplist without wal
110, 108 - vector with wal
232, 370 - vector without wal
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Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36957
Summary:
This adds p99.9 and p99.99 response times to the benchmark report and
adds a second report, report2.txt that has tests listed in test order rather
than the time in which they were run, so overwrite tests are listed for
all thread counts, then update etc.
Also changes fillseq to compress all levels to avoid write-amp from rewriting
uncompressed files when they reach the first level to compress.
Increase max_write_buffer_number to avoid stalls during fillseq and make
max_background_flushes agree with max_write_buffer_number.
See https://gist.github.com/mdcallag/297ff4316a25cb2988f7 for an example
of the new report (report2.txt)
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Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36537
Summary:
The --stats_interval_seconds determines interval for stats reporting
and overrides --stats_interval when set. I also changed tools/benchmark.sh
to report stats every 60 seconds so I can avoid trying to figure out a
good value for --stats_interval per test and per storage device.
Task ID: #6631621
Blame Rev:
Test Plan:
run tools/run_flash_bench, look at output
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Database Impact:
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- begin *PUBLIC* platform impact section -
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Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36189
Summary:
This makes run_flash_bench.sh configurable. Previously it was hardwired for 1B keys and tests
ran for 12 hours each. That kept me from using it. This makes it configuable, adds more tests,
makes the duration per-test configurable and refactors the test scripts.
Adds the seekrandomwhilemerging test to db_bench which is the same as seekrandomwhilewriting except
the writer thread does Merge rather than Put.
Forces the stall-time column in compaction IO stats to use a fixed format (H:M:S) which makes
it easier to scrape and parse. Also adds an option to AppendHumanMicros to force a fixed format.
Sometimes automation and humans want different format.
Calls thread->stats.AddBytes(bytes); in db_bench for more tests to get the MB/sec summary
stats in the output at test end.
Adds the average ingest rate to compaction IO stats. Output now looks like:
https://gist.github.com/mdcallag/2bd64d18be1b93adc494
More information on the benchmark output is at https://gist.github.com/mdcallag/db43a58bd5ac624f01e1
For benchmark.sh changes default RocksDB configuration to reduce stalls:
* min_level_to_compress from 2 to 3
* hard_rate_limit from 2 to 3
* max_grandparent_overlap_factor and max_bytes_for_level_multiplier from 10 to 8
* L0 file count triggers from 4,8,12 to 4,12,20 for (start,stall,stop)
Task ID: #6596829
Blame Rev:
Test Plan:
run tools/run_flash_bench.sh
Revert Plan:
Database Impact:
Memcache Impact:
Other Notes:
EImportant:
- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36075
Summary:
This is like readwhilewriting but uses Merge rather than Put in the writer thread.
I am using it for in-progress benchmarks. I don't think the other benchmarks for Merge
cover this behavior. The purpose for this test is to measure read performance when
readers might have to merge results. This will also benefit from work-in-progress
to add skewed key generation.
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Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D35115
Summary:
Without this change about half of the updaterandom reads and merge puts will be for keys that don't exist.
I think it is better for these tests to start with a full database and use fillseq to fill it.
Task ID: #
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- begin *PUBLIC* platform impact section -
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- end platform impact -
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D35043
Summary:
Single threaded tests -> sync=0 Multi threaded tests -> sync=1 by default unless DB_BENCH_NO_SYNC is defined.
Also added updaterandom and mergerandom with putOperator. I am waiting for some results from udb on this.
Test Plan:
DB_BENCH_NO_SYNC=1 WAL_DIR=/tmp OUTPUT_DIR=/tmp/b DB_DIR=/tmp ./tools/benchmark.sh debug,bulkload,fillseq,overwrite,filluniquerandom,readrandom,readwhilewriting,updaterandom,mergerandom
WAL_DIR=/tmp OUTPUT_DIR=/tmp/b DB_DIR=/tmp ./tools/benchmark.sh debug,bulkload,fillseq,overwrite,filluniquerandom,readrandom,readwhilewriting,updaterandom,mergerandom
Verify sync settings
Reviewers: sdong, MarkCallaghan, igor, rven
Reviewed By: igor, rven
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D34185
Summary:
A command line like this to run all the tests:
source benchmark.config.sh && nohup ./benchmark.sh 'bulkload,fillseq,overwrite,filluniquerandom,readrandom,readwhilewriting'
where
benchmark.config.sh is:
export DB_DIR=/data/mysql/rocksdata
export WAL_DIR=/txlogs/rockswal
export OUTPUT_DIR=/root/rocks_benchmarking/output
Will fail for the tests that need a new DB .
Also 1) set disable_data_sync=0 and 2) add debug mode to run through all the tests more quickly
Test Plan: run ./benchmark.sh 'debug,bulkload,fillseq,overwrite,filluniquerandom,readrandom,readwhilewriting' and verify that there are no complaints about WAL dir not being empty.
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D30909
Summary: as title
Test Plan: ran it
Reviewers: yhchiang, igor, sdong, MarkCallaghan
Reviewed By: MarkCallaghan
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D25563
Summary: Try to match some parameters from Dhruba's benchmarks on github
Test Plan: ran it
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24687
Summary:
Hope these scripts will allow people to run/repro benchmark easily
I think it is time to re-run flash benchmarks and report results
Please comment if any other benchmark runs are needed
Test Plan: ran it
Reviewers: yhchiang, igor, sdong
Reviewed By: igor
Subscribers: dhruba, MarkCallaghan, leveldb
Differential Revision: https://reviews.facebook.net/D23139
Gunnar Kudrjavets