From mboxrd@z Thu Jan  1 00:00:00 1970
From: dean gaudet <dean@arctic.org>
Subject: Re: XFS sunit/swidth for raid10
Date: Thu, 22 Mar 2007 23:48:19 -0700 (PDT)
Message-ID: <Pine.LNX.4.64.0703222347450.9269@twinlark.arctic.org>
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To: Peter Rabbitson <rabbit@rabbit.us>
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On Thu, 22 Mar 2007, Peter Rabbitson wrote:

> dean gaudet wrote:
> > On Thu, 22 Mar 2007, Peter Rabbitson wrote:
> > 
> > > Hi,
> > > How does one determine the XFS sunit and swidth sizes for a software
> > > raid10
> > > with 3 copies?
> > 
> > mkfs.xfs uses the GET_ARRAY_INFO ioctl to get the data it needs from
> > software raid and select an appropriate sunit/swidth...
> > 
> > although i'm not sure i agree entirely with its choice for raid10:
> 
> So do I, especially as it makes no checks for the amount of copies (3 in my
> case, not 2).
> 
> > it probably doesn't matter.
> 
> This was essentially my question. For an array -pf3 -c1024 I get swidth = 4 *
> sunit = 4MiB. Is it about right and does it matter at all?

how many drives?

-dean