Horton

Re: MultiXact\SLRU buffers configuration

Васильев Дмитрий <vadv.mkn@gmail.com>

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From: Васильев Дмитрий <vadv.mkn@gmail.com>
To: Andrey Borodin <x4mmm@yandex-team.ru>
Cc: Thomas Munro <thomas.munro@gmail.com>, Gilles Darold <gilles@darold.net>, Tomas Vondra <tomas.vondra@enterprisedb.com>, Tomas Vondra <tomas.vondra@2ndquadrant.com>, Alexander Korotkov <aekorotkov@gmail.com>, Anastasia Lubennikova <a.lubennikova@postgrespro.ru>, Daniel Gustafsson <daniel@yesql.se>, Kyotaro Horiguchi <horikyota.ntt@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2021-06-14T17:40:16Z
Lists: pgsql-hackers 
пн, 14 июн. 2021 г. в 15:07, Andrey Borodin <x4mmm@yandex-team.ru>:

> PFA patch implementing this idea.
>

I'm benchmarked v17 patches.
Testing was done on a 96-core machine, with PGDATA completely placed in
tmpfs.
PostgreSQL was built with CFLAGS -O2.

for-update PgBench script:
\set aid random_zipfian(1, 100, 2)
begin;
select :aid from pgbench_accounts where aid = :aid for update;
update pgbench_accounts set abalance = abalance + 1 where aid = :aid;
update pgbench_accounts set abalance = abalance * 2 where aid = :aid;
update pgbench_accounts set abalance = abalance - 2 where aid = :aid;
end;

Before each test sample data was filled with "pgbench -i -s 100", testing
was performed 3 times for 1 hour each test.
The benchmark results are presented with changing
multi_xact_members_buffers and multicast_offsets_buffers (1:2 respectively):
settings                          tps
multixact_members_buffers_64Kb   693.2
multixact_members_buffers_128Kb  691.4
multixact_members_buffers_192Kb  696.3
multixact_members_buffers_256Kb  694.4
multixact_members_buffers_320Kb  692.3
multixact_members_buffers_448Kb  693.7
multixact_members_buffers_512Kb  693.3
vanilla                          676.1

Best regards, Dmitry Vasiliev.

Commits

  1. Rework new SLRU test with injection points

  2. injection_point: Add injection_points.stats

  3. injection_points: Add initialization of shmem state when loading module

  4. Add injection-point test for new multixact CV usage

  5. Use conditional variable to wait for next MultiXact offset

  6. Improve performance of subsystems on top of SLRU

  7. Adjust VACUUM hastup LP_REDIRECT comments.

  8. Test replay of regression tests, attempt II.