Fwd: [BUG]: the walsender does not update its IO statistics until it exits
Xuneng Zhou <xunengzhou@gmail.com>
From: Xuneng Zhou <xunengzhou@gmail.com>
To: PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2025-03-13T11:35:24Z
Lists: pgsql-hackers
Sorry, forgot to cc this one too. ---------- Forwarded message --------- 发件人: Xuneng Zhou <xunengzhou@gmail.com> Date: 2025年3月13日周四 19:29 Subject: Re: [BUG]: the walsender does not update its IO statistics until it exits To: Bertrand Drouvot <bertranddrouvot.pg@gmail.com> Hi, Given that PGSTAT_MIN_INTERVAL is the go-to setting for stats flushes * Unless called with 'force', pending stats updates are flushed happen once * per PGSTAT_MIN_INTERVAL (1000ms). When not forced, stats flushes do not * block on lock acquisition, except if stats updates have been pending for * longer than PGSTAT_MAX_INTERVAL (60000ms). * * Whenever pending stats updates remain at the end of pgstat_report_stat() a * suggested idle timeout is returned. Currently this is always * PGSTAT_IDLE_INTERVAL (10000ms). Callers can use the returned time to set up * a timeout after which to call pgstat_report_stat(true), but are not * required to do so. I am curious about the reason for this: > 1. maybe relying on PGSTAT_IDLE_INTERVAL would make more sense? In both > case > PGSTAT_MIN_INTERVAL or PGSTAT_MIN_INTERVAL, I'm not sure there is a need to > update the related doc. > > PGSTAT_IDLE_INTERVAL seems to reduce the frequency even more. > > With the attached in place, the number of times the stats are being flushed > reduce drastically but still seems enough to get an accurate idea of the > walsender > IO activity. Thoughts? > > >
Commits
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Flush the IO statistics of active WAL senders more frequently
- e2a82cd23a88 16.9 landed
- 5cbbe70a9cc6 17.5 landed
- 039549d70f6a 18.0 landed
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Optimize check for pending backend IO stats
- 6d3ea48ff1ae 18.0 landed