From: Franck Routier <franck.routier@axege.com>
To: pgsql-performance@postgresql.org
Subject: Re: What happens between end of explain analyze and end of query execution ?
Date: Sat, 06 Apr 2013 10:13:37 +0200
Message-ID: <515FD931.9070306@axege.com> (raw)
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Le 05/04/2013 16:18, Nikolas Everett a écrit :
> On Fri, Apr 5, 2013 at 9:55 AM, Franck Routier
> <franck.routier@axege.com <mailto:franck.routier@axege.com>> wrote:
>
> Le 04/04/2013 21:08, Tom Lane a écrit :
> Maybe the statistics tables for sandia and saneds are in a bad
> shape ? (don't know how to check this).
>
> Regards,
>
> Franck
>
>
>
> Could this be caused by system table bloat?
>
> Also, can you check how long it takes to plan:
> 1. A query without a table at all (SELECT NOW())
> 2. A query with an unrelated table
>
> Again, what version of PostgreSQL is this?
PG 8.4.8
select now() is quick (15ms from pgadmin)
But I can reproduce the problem on other tables : explain on a query
with 4 join takes 4.5 seconds on an other set of tables...
System bloat... maybe. Not sure how to check. But as Tom asked,
default_statistics_target is 5000. Maybe the problem is here ? What
should I look after in pg_statistic to tell is there is a prolem here ?
Regards,
Franck
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To: pgsql-performance@postgresql.org
Cc: franck.routier@axege.com
Subject: Re: What happens between end of explain analyze and end of query execution ?
In-Reply-To: <515FD931.9070306@axege.com>
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