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Date: Wed, 30 May 2007 17:40:50 +0200
To: "Luke Lonergan" <LLonergan@greenplum.com>,
	"Michael Stone" <mstone+postgres@mathom.us>,
	pgsql-performance@postgresql.org
Subject: Re: setting up raid10 with more than 4 drives
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	Oh by the way, I saw a nifty patch in the queue :

Find a way to reduce rotational delay when repeatedly writing last WAL page
Currently fsync of WAL requires the disk platter to perform a full  
rotation to fsync again.
One idea is to write the WAL to different offsets that might reduce the  
rotational delay.

	This will not work if the WAL is on RAID1, because two disks never spin  
exactly at the same speed...