Re: Is autovacuum doing a wraparound-avoiding VACUUM?

On Thu, 2008-07-17 at 17:10 -0400, Alvaro Herrera wrote:
> Simon Riggs wrote:
> >
> > Is autovacuum doing a wraparound-avoiding VACUUM?
> > Currently, no easy way to tell.
> >
> > Patch to change message of autovac in pg_stat_activity when we are
> > performing an anti-wraparound VACUUM.
>
> I just obsoleted this patch.  The new patch should be easier to do
> though -- just a one line change I think.
>
> I don't like your wording though; it feels too verbose (and you're
> losing the ANALYZE in case it's doing both things).  How about
>
>     snprintf(activity, MAX_AUTOVAC_ACTIV_LEN,
>         "autovacuum: VACUUM%s%s", vac
>         tab->at_doanalyze ? " ANALYZE" : "",
>         tab->at_wraparound ? " (wraparound)" : "");

Yes, looks good.

Losing the ANALYZE was conscious, but in retrospect is something we
might live to regret. Yours is better.

> You're not proposing it for 8.3 right?

I think I am. It's an important diagnostic for your other fix.

We need to be able to tell the difference between a wraparound and other
weird situations.

--
 Simon Riggs           www.2ndQuadrant.com
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