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From: Greg Smith <greg@2ndquadrant.com>
To: Marti Raudsepp <marti@juffo.org>
Cc: Kevin Grittner <Kevin.Grittner@wicourts.gov>
Cc: sthomas@peak6.com, Maciek Sakrejda <msakrejda@truviso.com>
Cc: felix <crucialfelix@gmail.com>
Cc: pgsql-performance@postgresql.org <pgsql-performance@postgresql.org>
Subject: Re: Really really slow select count(*)
Date: Tue, 08 Feb 2011 15:09:40 -0500
Message-ID: <4D51A304.4070003@2ndquadrant.com> (raw)
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Marti Raudsepp wrote:
> I couldn't find any past discussions about changing the default to "fast".
> Are there any reasons why that cannot be done in a future release?
>   

Well, it won't actually help as much as you might think.  It's possible 
for clients to be in a state where fast shutdown doesn't work, either.  
You either have to kill them manually or use an immediate shutdown.

Kevin and I both suggested a "fast plus timeout then immediate" behavior 
is what many users seem to want.  My comments were at 
http://archives.postgresql.org/pgsql-hackers/2009-09/msg01145.php ; for 
an example of how fast shutdown can fail see 
http://archives.postgresql.org/pgsql-bugs/2009-03/msg00062.php

-- 
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
PostgreSQL Training, Services, and 24x7 Support  www.2ndQuadrant.us
"PostgreSQL 9.0 High Performance": http://www.2ndQuadrant.com/books




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