Re: optimizing CleanupTempFiles

On Thu, 2008-09-18 at 09:23 +0300, Heikki Linnakangas wrote:
> Tom Lane wrote:
> > Alvaro Herrera <alvherre(at)commandprompt(dot)com> writes:
> >> BTW in testing this patch I was surprised by the fact that temp tables
> >> files are removed at checkpoint time,
> >
> > [ blink... ] Doesn't look like that should happen. What is your
> > test case?
>
> Hmph, must be because of the patch from last winter to prevent
> relfilenode reuse until next checkpoint. Looks like we didn't make an
> exception for temporary tables. Although it's harmless...

An unfortunate choice of words! Harmless is not how your average DBA
would describe it when their disk fills and they are apparently unable
to reduce space consumption. So there is still a problem there even if
we fix the temp files portion of it.

Seems like a complete fix must have some kind of pressure relief valve
for when things get full. Disk overflow is a much more likely problem
than a relfilenode recycling problem.

--
Simon Riggs www.2ndQuadrant.com
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