From: Joshua D. Drake <jd@commandprompt.com>
To: Ron St-Pierre <ron.pgsql@shaw.ca>
Cc: Alvaro Herrera <alvherre@commandprompt.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: 12 hour table vacuums
Date: Tue, 23 Oct 2007 10:41:13 -0700
Message-ID: <20071023104113.1f4d0aa0@scratch> (raw)
In-Reply-To: <471E2895.4030601@shaw.ca>
References: <471E18ED.3090704@shaw.ca>
<20071023161204.GK18013@alvh.no-ip.org>
<471E2895.4030601@shaw.ca>
On Tue, 23 Oct 2007 10:00:05 -0700
Ron St-Pierre <ron.pgsql@shaw.ca> wrote:
> Alvaro Herrera wrote:
> > Ron St-Pierre wrote:
> >
> >
> >> Okay, here's our system:
> >> postgres 8.1.4
> >>
> >
> > Upgrade to 8.1.10
> >
> Any particular fixes in 8.1.10 that would help with this?
> >
> >> Here's the table information:
> >> The table has 140,000 rows, 130 columns (mostly NUMERIC), 60
> >> indexes.
> >
> > 60 indexes? You gotta be kidding. You really have 60 columns on
> > which to scan?
> >
> >
> Really. 60 indexes. They're the most commonly requested columns for
> company information (we believe). Any ideas on testing our
> assumptions about that? I would like to know definitively what are
> the most popular columns. Do you think that rules would be a good
> approach for this? (Sorry if I'm getting way off topic here)
I suggest you:
1. Turn on stats and start looking in the stats columns to see what
indexes are actually being used.
2. Strongly review your normalization :)
Joshua D. Drake
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To: pgsql-performance@postgresql.org
Cc: jd@commandprompt.com, ron.pgsql@shaw.ca, alvherre@commandprompt.com
Subject: Re: 12 hour table vacuums
In-Reply-To: <20071023104113.1f4d0aa0@scratch>
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