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From: Jan Grant <Jan.Grant@bristol.ac.uk>
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To: Chuck Swiger <cswiger@mac.com>
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Subject: Re: RAID1 vs RAID5 [ was Re: 1 processor vs. 2]
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On Thu, 4 Mar 2004, Chuck Swiger wrote:

> Also, RAID-5 performance degrades horribly if a drive is down, whereas RAID-1
> does fine...

Using the algorithm you indicate below, RAID-5 performance would not
degrade on the loss of a drive, it's start out that badly.

> A five-disk RAID-5 array has to read 4 sectors and write five sectors if you
> change one byte.

Wrong; see previous response.


-- 
jan grant, ILRT, University of Bristol. http://www.ilrt.bris.ac.uk/
Tel +44(0)117 9287088 Fax +44 (0)117 9287112 http://ioctl.org/jan/
Q: What's yellow and equivalent to the axiom of choice? A: Zorn's lemon.