Message-ID: <4C911F68.6020507@ca.afilias.info>
Date: Wed, 15 Sep 2010 15:32:56 -0400
From: Brad Nicholson <bnichols@ca.afilias.info>
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To: pgsql-performance@postgresql.org
Subject: Re: locking issue on simple selects?
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  On 10-09-15 03:07 PM, Tobias Brox wrote:
> On 15 September 2010 15:39, Tom Lane<tgl@sss.pgh.pa.us>  wrote:
>> An exclusive lock will block selects too.  Have you looked into pg_locks
>> for ungranted lock requests?
> Well - I thought so, we have a logging script that logs the content of
> the pg_locks table, it didn't log anything interesting but it may be a
> problem with the script itself.  It does an inner join on
> pg_locks.relation = pg_class.oid but when I check now this join seems
> to remove most of the rows in the pg_locks table.  Does it make sense
> at all to join pg_class with pg_locks?  I will ask the sysadm to
> change to an outer join as for now.
>

You can also enable log_lock_waits and the lock waits will appear in 
your Postgres logs.

-- 
Brad Nicholson  416-673-4106
Database Administrator, Afilias Canada Corp.