From: Jan de Visser <jdevisser@digitalfairway.com>
To: pgsql-performance@postgresql.org
Subject: Re: Query runs 38 seconds for small database!
Date: Mon, 8 May 2006 15:19:39 -0400
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On Monday 08 May 2006 14:10, Andrus wrote:
> > The only reason for being so conservative that I'm aware of was that it
> > was a best guess. Everyone I've talked to cuts the defaults down by at
> > least a factor of 2, sometimes even more.
>
> Can we ask that Tom will change default values to 2 times smaller in 8.1.4
> ?
>
> > BTW, these parameters are already tweaked from what we started with in
> > contrib/pg_autovacuum. It would allow a table to grow to 2x larger than
> > it should be before vacuuming, as opposed to the 40% that the current
> > settings allow. But even there, is there any real reason you want to
> > have 40% bloat? To make matters worse, those settings ensure that all
> > but the smallest databases will suffer runaway bloat unless you bump up
>
>  recprd> the FSM settings.
>
> I created empty table konto and loaded more that 219 records to it during
> database creation.
> So it seems that if table grows from zero to more than 219 times larger
> then it was still not processed.

That's because you need at least 500 rows for analyze and 100 for a vacuum,=
=20
(autovacuum_vacuum_threshold =3D 1000, autovacuum_analyze_threshold =3D 500=
).

>
> Andrus.

jan

>
>
>
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Jan de Visser =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 jdevisser@digitalfair=
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=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 Baruk Khazad! Khazad ai-menu!
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