From: Adrian Moisey <adrian@careerjunction.co.za>
To: pgsql-performance@postgresql.org
Subject: Re: strange pauses
Date: Fri, 18 Jan 2008 12:58:06 +0200
Message-ID: <4790863E.4000309@careerjunction.co.za> (raw)
In-Reply-To: <478DE16F.50308@archonet.com>
References: <478DDF83.8070106@careerjunction.co.za>
<478DE16F.50308@archonet.com>
Hi
>> If I tail the logs, I see a steady stream of functions that took
>> longer then 5 seconds. But every now and then I see nothing for 3
>> minutes and after that a whole bunch (about 20 - 30) queries all
>> finishing at the same second.
>
> Search this list for references to "checkpoints". If you run
> vmstat/iostat for a bit you should see bursts of disk activity at those
> times.
>
> Counter-intuitively you probably want *more* checkpoints (with less data
> to write out each time), but see the list archives for discussion. Also
> check the manuals for some background info.
We use a lot of checkpoints in our database, we don't care about these
much. We think this is causing the checkpoint to write a lot of data at
checkpoint time. Can we stop this behavior ?
--
Adrian Moisey
System Administrator | CareerJunction | Your Future Starts Here.
Web: www.careerjunction.co.za | Email: adrian@careerjunction.co.za
Phone: +27 21 686 6820 | Mobile: +27 82 858 7830 | Fax: +27 21 686 6842
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To: pgsql-performance@postgresql.org
Cc: adrian@careerjunction.co.za
Subject: Re: strange pauses
In-Reply-To: <4790863E.4000309@careerjunction.co.za>
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