Re: lazy vacuum and AccessExclusiveLock

Tom Lane wrote:
> Alvaro Herrera <alvherre(at)commandprompt(dot)com> writes:
> > An alternative solution would be to lower the vacuum delay settings before
> > starting the truncating phase, but this doesn't work very well in autovacuum
> > due to the autobalancing code (which can cause other processes to change our
> > cost delay settings). This case could be considered in the balancing code, but
> > it is simpler this way.
>
> I don't think autovacuum has a problem --- if someone requests a
> conflicting lock, autovac will get kicked off, no? The OP's problem
> comes from doing a manual vacuum. Perhaps "don't do that" is a good
> enough answer.

Hah, that was part of the commit message, which predates autovacuum
getting kicked out in case of conflicting locks IIRC.

I think the process being described is unusual enough that a manual
vacuum at just the right time is warranted ...

--
Alvaro Herrera http://www.CommandPrompt.com/
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