Re: We probably need autovacuum_max_wraparound_workers - Mailing list pgsql-hackers

From Tom Lane
Subject Re: We probably need autovacuum_max_wraparound_workers
Date
Msg-id 9169.1340936802@sss.pgh.pa.us
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In response to Re: We probably need autovacuum_max_wraparound_workers  (Josh Berkus <josh@agliodbs.com>)
Responses Re: We probably need autovacuum_max_wraparound_workers
List pgsql-hackers
Josh Berkus <josh@agliodbs.com> writes:
> Well, I think it's "plausible but wrong under at least some common
> circumstances".  In addition to seeking, it ignores FS cache effects
> (not that I have any idea how to account for these mathematically).  It
> also makes the assumption that 3 autovacuum workers running at 1/3 speed
> each is better than having one worker running at full speed, which is
> debatable.

Well, no, not really, because the original implementation with only one
worker was pretty untenable.  But maybe we need some concept like only
one worker working on *big* tables?  Or at least, less than max_workers
of them.
        regards, tom lane


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