Insert benchmark: Postgres, InnoDB and MyRocks with low concurrency

This has results for the insert benchmark using Postgres, InnoDB and MyRocks. For an overview of the insert benchmark see here and here. Some information on the performance summaries generated by my test scripts is here. I used small servers and ran the test at low concurrency (1 or 2 threads) for cached and IO-bound workloads. The insert benchmark has several phases and the interesting phases are: insert-only without secondary indexes, insert-only with 3 secondary indexes and then range queries with rate-limited inserts.

Performance reports are provided for:

• Postgres versions 12.11, 13.7, 14.6 and 15.1: cached and IO-bound
• InnoDB 5.6.49, 5.7.35, 8.0.21 and 8.0.31: cached and IO-bound
• MyRocks 5.6.35 and 8.0.28: cached and IO-bound

Disclaimer - I used a small server and will soon repeat this on larger servers and with more concurrency.

tl;dr

• Postgres is boring: no CPU regressions from version 12 to 15 for cached and IO-bound workloads.
• The insert benchmark found a CPU regression in 15beta1 which was quickly fixed.
• InnoDB with a cached workload has large CPU regressions from 5.6 to 8.0.
• This is visible here. By large I mean that the insert and query rates for InnoDB in 8.0.31 are ~64% and ~75% of the rates in 5.6. The root cause is new CPU overhead in code other than the storage engine.
• MyRocks with a cached workload has large CPU regressions from 5.6 to 8.0
• This is visible here. The regression for insert-only without secondary indexes is similar to InnoDB. The regression for range queries is smaller than the one above for InnoDB (throughput declines by ~8%). The root cause is new CPU overhead in upstream MySQL.
• InnoDB with an IO-bound workload has large CPU regressions in the insert-only without secondary index phase, which is normally CPU-bound. See here.
• The regression is similar to what I describe above for the cached workload. Throughput for the insert-only with secondary index phase and range queries with rate-limited inserts phase is better in 8.0.31 than 5.6.
• MyRocks with an IO-bound workload has CPU regressions that are similar to MyRocks with a cached workload. See here.