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Message-ID: <499C701D.2010403@d0pefish.de>
Date: Wed, 18 Feb 2009 21:31:25 +0100
From: Peter Hinse <loco@d0pefish.de>
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To: Tom Lane <tgl@sss.pgh.pa.us>
CC: pgsql-admin@postgresql.org
Subject: Re: lseek
References: <499B2423.3000809@d0pefish.de> <9125.1234906484@sss.pgh.pa.us>
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Tom Lane schrieb:
> Peter Hinse <loco@d0pefish.de> writes:
>> More info: the statement is an INSERT with some huge subselects, running
>> every night on a PGSQL 8.3.6 on CentOS 4.7 x86_64. In 97% of all
>> occasions, the job terminates in about 1-2 minutes - however, sometimes
>> it just hangs. If terminated with kill <pid> and restarted, it always
>> terminates.
> 
> Define "huge" --- you mean a lot of relations in the query?  If you have
> enough to trigger GEQO optimization, it could be that it's sometimes
> picking a bad plan.  You might try raising the geqo threshold to more
> relations than that; or if this results in unacceptably long planning
> time, increase geqo_effort instead.

Hi Tom,

thanks for your hints, I will check this with our R&D people. And yes:
with "huge" I meant the number of relations.

Regards,

	Peter