On Wed, 23 Nov 2022 at 20:29, sirisha chamarthi <sirichamarthi22@gmail.com> wrote: > I ran your test1 exactly like your setup except the row count is 3000000 (with 13275 blocks). Shared_buffers is 128MB and the hardware configuration details at the bottom of the mail. It appears Master + 0001 + 0005 regressed compared to master slightly .
Thank you for running these tests.
Can you share if the plans used for these queries was a parallel plan? I had set max_parallel_workers_per_gather to 0 to remove the additional variability from parallel query.
Also, 13275 blocks is 104MBs, does EXPLAIN (ANALYZE, BUFFERS) indicate that all pages were in shared buffers? I used pg_prewarm() to ensure they were so that the runs were consistent.
I reran the test with setting max_parallel_workers_per_gather = 0 and with pg_prewarm. Appears I missed some step while testing on the master, thanks for sharing the details. New numbers show master has higher latency than Master + 0001 + 0005.
