Message-ID: <50141C7A.4050607@oneit.com.au>
Date: Sun, 29 Jul 2012 01:08:10 +0800
From: David Barton <dave@oneit.com.au>
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To: Tom Lane <tgl@sss.pgh.pa.us>, pgsql-performance@postgresql.org
Subject: Re: Postgres 9.1.4 - high stats collector IO usage
References: <50136B8D.7070502@oneit.com.au> <29996.1343492034@sss.pgh.pa.us>
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Thanks so much, Tom.

That did the job.  I increased it to every 15 minutes and it has dropped 
substantially even though the pgstat.stat file is over 1 MB again.

It is unfortunate that the IO utilisation of this seems to be O(n^2) as 
that is a big impediment to shared hosting.  Is there any type of bounty 
system where people can contribute to developing features?

Regards, David

On 29/07/12 00:13, Tom Lane wrote:
> David Barton <dave@oneit.com.au> writes:
>> I am running postgres 9.1.4 on Ubuntu 12.04 and the stats collector is
>> generating very high IO usage even when nothing appears to be happening
>> on the system.
>> I have roughly 150 different databases, each of which is running in 1 of
>> roughly 30 tablespaces.  The databases are small (the dump of most is
>> are under 100M, and all but 3 are under 1G, nothing larger than 2G).
> That's a lot of databases.  I think your problem probably stems from
> autovacuum madly trying to cover all of them.  Backing off (increasing)
> autovacuum_naptime to slow its cycle might help.
>
> 			regards, tom lane
>