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NikolayS / howto.md
Last active January 29, 2023 20:25
log_min_duration_statement = 0 and I/O impact

How to get an estimate of the impact of writing Postgres logs with log_min_duration_statement = 0:

  1. Do select pg_stat_statements_reset(); and wait N seconds (where N >> 60 – say 1-24 hours, covering typical busy hours). Remember when it was, and write down somewhere – this timestamp will be needed!

  2. Check if select count(*) from pg_stat_statements is lower than pg_stat_statements.max. If it's equal to it, then raise pg_stat_statements.max and restart with the step 1.

  3. Get the estimate:

\set TS_PGSS_RESET 'XXXX-XX-XX XX:XX:XX';