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Message-ID: <4C0E7E3E.2070309@2ndquadrant.com>
Date: Tue, 08 Jun 2010 13:30:38 -0400
From: Greg Smith <greg@2ndquadrant.com>
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To: Thomas Kellerer <spam_eater@gmx.net>
CC: pgsql-admin@postgresql.org
Subject: Re: Details about pg_stat_bgwriter
References: <hulnta$mqe$1@dough.gmane.org>
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Thomas Kellerer wrote:
> If I want to identify a possible bottleneck with the bgwriter, for 
> what kind of numbers do I need to watch out?
You don't much with a single snapshot of pg_stat_bgwriter data.  Try 
saving this instead:

select *,now() from pg_stat_bgwriter;

And then take another snapshot at least a few hours later, preferably 
the next day.  With two snapshots and timestamps on them, then it's 
possible to make some sense of the numbers.

-- 
Greg Smith  2ndQuadrant US  Baltimore, MD
PostgreSQL Training, Services and Support
greg@2ndQuadrant.com   www.2ndQuadrant.us