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Date: Thu, 08 Jul 2010 13:50:52 -0600
From: David Boreham <david_list@boreham.org>
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CC: pgsql-performance@postgresql.org
Subject: Re: performance on new linux box
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On 7/8/2010 1:47 PM, Ryan Wexler wrote:
> Thanks for the explanations that makes things clearer.  It still 
> amazes me that it would account for a 5x change in IO.

The buffering allows decoupling of the write rate from the disk rotation 
speed.
Disks don't spin that fast, at least not relative to the speed the CPU 
is running at.