Re: Massive performance issues - Mailing list pgsql-performance

From Steinar H. Gunderson
Subject Re: Massive performance issues
Date
Msg-id 20050901215245.GA4242@uio.no
Whole thread Raw
In response to Re: Massive performance issues  (Matthew Sackman <matthew@lshift.net>)
Responses Re: Massive performance issues
List pgsql-performance
On Thu, Sep 01, 2005 at 10:13:59PM +0100, Matthew Sackman wrote:
> Well that's the thing - on the queries where it decides to use the index
> it only reads at around 3MB/s and the CPU is maxed out, whereas when it
> doesn't use the index, the disk is being read at 60MB/s. So when it
> decides to use an index, I don't seem to be IO bound at all. Or at least
> that's the way it seems to me.

You are I/O bound; your disk is doing lots and lots of seeks. The SATA
interface is not the bottleneck; the disk's ability to rotate and move its
heads is.

/* Steinar */
--
Homepage: http://www.sesse.net/

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