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From: Jeff Frost <jeff@pgexperts.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andres Freund <andres@2ndquadrant.com>
Cc: Matheus de Oliveira <matioli.matheus@gmail.com>
Cc: Soni M <diptatapa@gmail.com>
Cc: Heikki Linnakangas <hlinnakangas@vmware.com>
Cc: pgsql-performance <pgsql-performance@postgresql.org>
Subject: Re: Postgres Replaying WAL slowly
Date: Mon, 30 Jun 2014 14:52:22 -0700
Message-ID: <571D044B-260A-4E06-ACBC-8869B8F73C0F@pgexperts.com> (raw)
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On Jun 30, 2014, at 1:46 PM, Jeff Frost <jeff@pgexperts.com> wrote:

>> So it seems like we have a candidate explanation.  I'm a bit surprised
>> that StandbyReleaseLocks would get this slow if there are only a dozen
>> AccessExclusiveLocks in place at any one time, though.  Perhaps that
>> was a low point and there are often many more?
>> 
>> 	
> 
> Entirely possible that it was a low point.  We'll set up some monitoring to track the number of AccessExclusiveLocks and see how much variance there is throughout the day.


Since we turned on the monitoring for that, we had a peak of 13,550 AccessExclusiveLocks.  So far most of the samples have been in the double digit, with that and two other outliers: 6,118 and 12,747.=

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