Date: Wed, 23 Apr 2008 01:10:26 +0900
From: Bryan Buecking <buecking@gmail.com>
To: Erik Jones <erik@myemma.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: CPU bound at 99%
Message-ID: <20080422161020.GE5961@starling-software.com>
References: <20080422153045.GB5961@starling-software.com>
	<DCD21583-38AA-4E01-BA29-39A7078259FE@myemma.com>
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On Tue, Apr 22, 2008 at 10:55:19AM -0500, Erik Jones wrote:
> On Apr 22, 2008, at 10:31 AM, Bryan Buecking wrote:
> 
> >max_connections = 2400
> 
> That is WAY too high.  Get a real pooler, such as pgpool, and drop  
> that down to 1000 and test from there.

I agree, but the number of idle connections dont' seem to affect
performace only memory usage. I'm trying to lessen the load of
connection setup. But sounds like this tax is minimal?

When these issues started happening, max_connections was set to 1000 and
I was not using persistent connections.

> I see you mentioned 500 concurrent connections. Are each of those
> connections actually doing something?

Yes out of the 2400 odd connections, 500 are either in SELECT or RESET.

> My guess that once you cut down on the number actual connections
> you'll find that each connection can get it's work done faster
> and you'll see that number drop significantly.

I agree, but not in this case.  I will look at using pooling. 
-- 
Bryan Buecking				http://www.starling-software.com