Message-ID: <4DDF1B2F.4050708@postnewspapers.com.au>
Date: Fri, 27 May 2011 11:31:59 +0800
From: Craig Ringer <craig@postnewspapers.com.au>
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To: Junghwe Kim <junghwe.kim76@gmail.com>
CC: pgsql-performance@postgresql.org
Subject: Re: Is any effect other process performance after vaccumdb finished ?
References: <BANLkTim+aE27feMk8xu4MX3z0bcxNkmxvA@mail.gmail.com>
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On 27/05/2011 9:58 AM, Junghwe Kim wrote:
> Hi.
>
> First extremely thanks for your works about postgresql .
>
> I wonder that after executing 'vaccumdb  -z'  some other process can not
> read their own msg queue during 2 ~ 3 minuts.

The most likely cause is checkpoint activity. Enable checkpoint logging 
and examine your server logs.

> vaccum executed every hour. and The processes have not any relations
> between postgreql.

Instead of running vacuum from cron or some other scheduler, turn on 
autovacuum and set it to run aggressively. You will reduce the impact of 
vacuum if you run it *often* (every few minutes if not more frequently) 
and do so using autovacuum.

Best results will be had on PostgreSQL 8.4 or above.

Please read this if you need to follow up, so you include enough 
information that a more complete answer can be given:

   http://wiki.postgresql.org/wiki/Guide_to_reporting_problems

-- 
Craig Ringer

Tech-related writing at http://soapyfrogs.blogspot.com/