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Message-ID: <43E1F7BF.2050100@logix-tt.com>
Date: Thu, 02 Feb 2006 13:14:55 +0100
From: Markus Schaber <schabi@logix-tt.com>
Organization: Logical Tracking and Tracing International AG, Switzerland
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To: Michael Stone <mstone+postgres@mathom.us>
Cc: pgsql-performance@postgresql.org
Subject: Re: Where is my bottleneck?
References: <43D67496.2020203@androme.es> <20060130110047.GB9976@mathom.us>
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Hi, Michael,

Michael Stone wrote:

>>   I have a performance problem and I don't know where is my bottleneck.
> 
> [snip]
> 
>>   Most of the time the idle value is even higher than 60%.
> 
> It's generally a fairly safe bet that if you are running slow and your
> cpu is idle, your i/o isn't fast enough.

Or the query is misoptimized (low work_mem, missing indices) and cause
much more I/O than necessary.

HTH,
Markus

-- 
Markus Schaber | Logical Tracking&Tracing International AG
Dipl. Inf.     | Software Development GIS

Fight against software patents in EU! www.ffii.org www.nosoftwarepatents.org