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Message-ID: <4D1BC9F9.7060005@emolecules.com>
Date: Wed, 29 Dec 2010 15:53:29 -0800
From: Craig James <craig_james@emolecules.com>
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To: Tom Lane <tgl@sss.pgh.pa.us>
CC: pgsql-performance@postgresql.org
Subject: Re: long wait times in ProcessCatchupEvent()
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On 12/29/10 11:58 AM, Tom Lane wrote:
> Craig James<craig_james@emolecules.com>  writes:
>> On 12/29/10 6:28 AM, Julian v. Bock wrote:
>>> I have the problem that on our servers it happens regularly under a
>>> certain workload (several times per minute) that all backend processes
>>> get a SIGUSR1 and spend several seconds in ProcessCatchupEvent().
>
>> This sounds like the exact same problem I had on Postgres 8.3 and 8.4:
>
>> http://archives.postgresql.org/pgsql-performance/2010-04/msg00071.php
>
>> Updating to Postgres version 9 fixed it. Here is what appeared to be the best analysis of what was happening, but we never confirmed it.
>
>> http://archives.postgresql.org/pgsql-performance/2010-06/msg00464.php
>
> It happened for you on 8.4 too?  In that previous thread you were still
> on 8.3.  If you did see it on 8.4 then it wasn't sinval ...

My mistake - it was only 8.3.

Craig