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Date: Sun, 2 May 2010 18:12:25 -0400 (EDT)
From: "Stuart D. Gathman" <stuart@bmsi.com>
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Subject: Re: [linux-lvm] logical volumes and raid alignment
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To: LVM general discussion and development <linux-lvm@redhat.com>

On Sun, 2 May 2010, Alexander 'Leo' Bergolth wrote:

> My raid chunk size is 64k and I am using 5 data-bearing discs (raid 5
> with 6 discs), so the raid stripe size should be 64k * 5 = 320k.
> 
> But unfortunately the --physicalextentsize must be a power of 2, so I
> cannot use a multiple of 320k as the physical extent size.
> 
> What are your experiences with tuning and properly aligning lvm + raid?
> Does anyone know a workaround?

Use 4 data bearing disks.  Let #6 be a spare.  You're supposed to have
a spare anyway.

-- 
	      Stuart D. Gathman <stuart@bmsi.com>
    Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
"Confutatis maledictis, flammis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.