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From: Michael Monnerie <michael.monnerie@is.it-management.at>
To: xfs@oss.sgi.com
Subject: Re: sunit & swidth on RAID-1?
Date: Wed, 11 Feb 2009 22:12:28 +0100	[thread overview]
Message-ID: <200902112212.28571@zmi.at> (raw)
In-Reply-To: <20090211165316.GA4430@dentifrice>

On Mittwoch 11 Februar 2009 mike dentifrice wrote:
>         sunit=0      swidth=0 blks, unwritten=1
>         sectsz=512   sunit=0 blks
>
> What's the consequence of 0 values in this case?

XFS then knows that 512 byte (aka sector) alignment is sufficient, as 
RAID-1 will only write 512b to each disk and does not need full stripe 
unit writes like RAID-4/5/6 need. Therefore performance is better with 
the values you have.

mfg zmi
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  parent reply	other threads:[~2009-02-11 21:13 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-02-11 15:56 sunit & swidth on RAID-1? mike dentifrice
2009-02-11 16:42 ` Justin Piszcz
     [not found]   ` <20090211165316.GA4430@dentifrice>
2009-02-11 17:10     ` Justin Piszcz
2009-02-11 21:12     ` Michael Monnerie [this message]
2009-02-11 16:46 ` Eric Sandeen

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