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Message-ID: <500DEC9E.90603@ringerc.id.au>
Date: Tue, 24 Jul 2012 08:30:22 +0800
From: Craig Ringer <ringerc@ringerc.id.au>
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To: Jim Vanns <james.vanns@framestore.com>
CC: Martin French <Martin.French@romaxtech.com>,
	pgsql-performance@postgresql.org, pgsql-performance-owner@postgresql.org
Subject: Re: Odd blocking (or massively latent) issue - even with
 EXPLAIN
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On 07/23/2012 10:46 PM, Jim Vanns wrote:
> Nothing obvious - and we log a fair amount. No tmp table creations,
> no locks held.
>
> To add to this EXPLAIN reports it took only 0.23ms to run (for example)
> whereas the wall clock time is more like 20-30 minutes (or up to n hours
> as I said where everything appears to click back into place at the same
> time).
How many concurrent connections do you have?

--
Craig Ringer