How about counting the number of dead tuples examined and the number of live
tuples returned. As the ratio of dead tuples over live tuples visited
increases the table becomes a candidate for vacuuming.
-regards
richt
> -----Original Message-----
> From: pgsql-hackers-owner@postgresql.org
> [mailto:pgsql-hackers-owner@postgresql.org]On Behalf Of Tom Lane
> Sent: Tuesday, September 03, 2002 4:25 PM
> To: Mario Weilguni
> Cc: pgsql-hackers@postgresql.org
> Subject: Re: [HACKERS] possible vacuum improvement?
>
>
> "Mario Weilguni" <mario.weilguni@icomedias.com> writes:
> > That brings me to another point, can't the
> > statistics collector used for that?
>
> Hmm, that would be a different way of attacking the problem. Not sure
> offhand which is better, but it'd surely be worth considering both.
>
> Note that collecting of dead-tuple counts requires input from aborted
> transactions as well as successful ones. I don't recall whether the
> stats collector currently collects anything from aborted xacts; that
> might or might not be a sticky point.
>
> regards, tom lane
>
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