From: Andrew Sullivan <ajs@crankycanuck.ca>
To: pgsql-performance@postgresql.org
Subject: Re: 7.4 Checkpoint Question
Date: Thu, 29 Nov 2007 11:02:19 -0500
Message-ID: <20071129160219.GJ6226@crankycanuck.ca> (raw)
In-Reply-To: <1196349054.5651.19.camel@bnicholson-desktop>
References: <1196349054.5651.19.camel@bnicholson-desktop>
On Thu, Nov 29, 2007 at 10:10:54AM -0500, Brad Nicholson wrote:
> This is a _really _low volume system, less than 500 writes/hour. Normal
> operation sees checkpoint related spikes of around 200-300 milliseconds.
> We always checkpoint at the checkpoint timeout (every 5 minutes).
> During this one checkpoint, I'm seeing transactions running 2-3 seconds.
> During this time, writes are < 5/minute.
> What gives?
pg_dump? Remember that it has special locks approximately equivalent
(actually eq? I forget) with SERIALIZABLE mode, which makes things rather
different.
A
--
Andrew Sullivan
Old sigs will return after re-constitution of blue smoke
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To: pgsql-performance@postgresql.org
Cc: ajs@crankycanuck.ca
Subject: Re: 7.4 Checkpoint Question
In-Reply-To: <20071129160219.GJ6226@crankycanuck.ca>
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