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Re: hardware RAID sunit and swidth values?

To: linux-xfs@xxxxxxxxxxx
Subject: Re: hardware RAID sunit and swidth values?
From: Derek Glidden <dglidden@xxxxxxxxxxxxxxx>
Date: 11 Apr 2003 10:50:33 -0400
In-reply-to: <news2mail-slrnb9cnsc.156.gurubert-dated-1050042067.onpbonhn@xxxxxxxxxxxxxxx cs.epi>
References: <news2mail-slrnb9cnsc.156.gurubert-dated-1050042067.onpbonhn@xxxxxxxxxxxxxxx cs.epi>
Sender: linux-xfs-bounce@xxxxxxxxxxx
On Fri, 2003-04-11 at 02:24, Robert Sander wrote:
> Hi!
> 
> When creating an XFS volume on an external hardware RAID which has a
> stripe size of 128 1024k blocks, what are the preffered values for sunit
> and swidth.
> Or is there no performance degrade when using mkfs.xfs without
> specifying sunit and swidth explicitely? In that case sunit and swidth
> are set to 0.

With all due respect to the XFS guys, the manpage section on sunit and
swidth is very confusing.  Would someone be willing to write up a more
understandable explanation and post it to the FAQ since
sunit/swidth-related questions do come up relatively frequently?  (Not
me, because I don't fully understand the options either...)
 
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