Summary:
First, we made a small reduction in DURATION_RW as runs were exceeding 1 hour and colliding with subsequent runs.
See Mark Callaghan’s blog post at http://smalldatum.blogspot.com/2023/01/variance-in-rocksdb-benchmarks-on-cloud.html
Configuration parameters which are not consistent with the following email from Mark (see the blog post for more context) have been updated. Where Mark has defined the parameter and we haven't, we define it explicitly. We will need to further monitor for an expected reduction in variance of test times:
To match what I did:
---
nsecs=1800
dbdir=/data/m/rx
resultdir=bm.lc.nt1.cm1.d0
env WRITE_BUFFER_SIZE_MB=16 TARGET_FILE_SIZE_BASE_MB=16 MAX_BYTES_FOR_LEVEL_BASE_MB=64 MAX_BACKGROUND_JOBS=4 NUM_KEYS=20000000 CACHE_SIZE_MB=10240 DURATION_RW=$nsecs DURATION_RO=$nsecs MB_WRITE_PER_SEC=2 NUM_THREADS=1 COMPRESSION_TYPE=none CACHE_INDEX_AND_FILTER_BLOCKS=1 VALUE_SIZE=400 NUMA=1 MIN_LEVEL_TO_COMPRESS=3 COMPACTION_STYLE=leveled bash benchmark_compare.sh $dbdir $resultdir 7.8.fb
env WRITE_BUFFER_SIZE_MB=16 TARGET_FILE_SIZE_BASE_MB=16 MAX_BYTES_FOR_LEVEL_BASE_MB=64 MAX_BACKGROUND_JOBS=4 NUM_KEYS=200000000 CACHE_SIZE_MB=10240 DURATION_RW=$nsecs DURATION_RO=$nsecs MB_WRITE_PER_SEC=2 NUM_THREADS=1 COMPRESSION_TYPE=lz4 CACHE_INDEX_AND_FILTER_BLOCKS=1 VALUE_SIZE=400 NUMA=1 MIN_LEVEL_TO_COMPRESS=3 COMPACTION_STYLE=leveled bash benchmark_compare.sh $dbdir $resultdir 7.8.fb
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11074
Reviewed By: ajkr
Differential Revision: D42969668
Pulled By: cbi42
fbshipit-source-id: 1ea4e6a3901be4016108f93817eb58f74baac21a
Summary:
CI benchmarks refine configuration
Run only “essential” benchmarks, but for longer
Fix (reduce) the NUM_KEYS to ensure cached behaviour
Reduce level size to try to ensure more levels
Refine test durations again, more time per test, but fewer tests.
In CI benchmark mode, the only read test is readrandom.
There are still 3 mostly-read tests.
Goal is to squeeze complete run a little bit inside 1 hour so it doesn’t clash with the next run (cron scheduled for main branch), but it gets to run as long as possible, so that results are as credible as possible.
Reduce thread count to physical capacity, in an attempt to reduce throughput variance for write heavy tests. See Mark Callaghan’s comments in related documentation..
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10514
Reviewed By: ajkr
Differential Revision: D38952469
Pulled By: jay-zhuang
fbshipit-source-id: 72fa6bba897cc47066ced65facd1fd36e28f30a8