Subject: Re: Write-heavy pg_stats_collector on mostly idle server
From: "Joshua D. Drake" <jd@commandprompt.com>
Reply-To: jd@commandprompt.com
To: Josh Berkus <josh@agliodbs.com>
Cc: =?ISO-8859-1?Q?C=E9dric?= Villemain
	<cedric.villemain.debian@gmail.com>, pgsql-performance@postgresql.org
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	<AANLkTinpWWrDHR9KJNebgtbvpXpL4UdQszD0GxF+FWWu@mail.gmail.com>
	<4D507920.2030909@agliodbs.com>
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Organization: Command Prompt, Inc.
Date: Mon, 07 Feb 2011 15:12:36 -0800
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On Mon, 2011-02-07 at 14:58 -0800, Josh Berkus wrote:
> >> Anyone seen anything like this before?
> >>
> > 
> > it is the expected behavior, IIRC
> 
> OK.  It just seems kind of pathological for stats file writing to be 10X
> the volume of data writing.  I see why it's happening, but I think it's
> something we should fix.

I don't think it is expected. As I recall, it is something we fixed a
couple of major versions back (8.2?). It used to be that stats would
write every 500ms. We changed that to when they are asked for (via a
select from the table or something). Specifically because it could cause
this type of problem.

Am I thinking of something else?

I remember going back and forth with tgl about this, tgl?

JD

> 
> -- 
>                                   -- Josh Berkus
>                                      PostgreSQL Experts Inc.
>                                      http://www.pgexperts.com
> 

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