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To: Sten Spans <sten@blinkenlights.nl>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Mon, 02 May 2005 22:54:00 +0200."
             <Pine.SOC.4.61.0505022252190.787@tea.blinkenlights.nl> 
Date: Mon, 02 May 2005 23:06:49 +0200
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cc: Steven Hartland <killing@multiplay.co.uk>
cc: freebsd-performance@freebsd.org
cc: Allen <bsdlists@rfnj.org>
cc: Eric Anderson <anderson@centtech.com>
Subject: Re: Very low disk performance on 5.x 
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In message <Pine.SOC.4.61.0505022252190.787@tea.blinkenlights.nl>, Sten Spans w
rites:

>>> What about disk arrays that support RAID3?
>>
>> Would work for me, but most of them are dumbed down when they do RAID3:
>> they have to hard format the disks to 128 byte sector sizes and similar
>> madness in order to support 512 bytes sectors on the RAID3 volume.
>
>I would really love the 512 + 8 byte checksum stuff that mainframes
>and netapps do. Does GEOM simplify implementing something like this ?

Yes, GEOM works with arbitrary sectorsizes, but far from all current
GEOM classes does.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.