Re: PATCH to allow concurrent VACUUMs to not lock each

Alvaro has just applied a modified version of this patch.

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Hannu Krosing wrote:
> On E, 2005-05-23 at 11:42 -0400, Tom Lane wrote:
> > Hannu Krosing <hannu(at)skype(dot)net> writes:
> > > I can't think of any other cases where it could matter, as at least the
> > > work done inside vacuum_rel() itself seema non-rollbackable.
> >
> > VACUUM FULL's tuple-moving is definitely roll-back-able, so it might be
> > prudent to only do this for lazy VACUUM. But on the other hand, VACUUM
> > FULL holds an exclusive lock on the table so no one else is going to see
> > its effects concurrently anyway.
>
> Ok, this is a new version of the vacuum patch with the following changes
> following some suggestions in this thread.
>
> * changed the patch to affect only lazy vacuum
> * moved inVacuum handling to use PG_TRY
> * moved vac_update_relstats() out of lazy_vacuum_rel into a separate
> transaction. The code to do this may not be the prettiest, maybe it
> should use a separate struct.
>
> --
> Hannu Krosing <hannu(at)skype(dot)net>

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