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Subject: Re: Software RAID5 with 2.6.0-test
From: Andre Tomt <andre@tomt.net>
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Date: Thu, 09 Oct 2003 02:51:44 +0200
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On Thu, 2003-10-09 at 01:44, Måns Rullgård wrote:
> When I tried it, I was running 2.6.0-test4.  The RAID5 was 4 120 GB
> Seagate disks on a Highpoint controller.

<snip>

> The other thing that I don't like, is the performance of the RAID
> array.  The disks individually give ~40 MB/s read speed, but the array
> only measures 25 MB/s.  I was of the impression, that RAID5 would give
> read speeds at least equal to the underlying disks.  Is this
> incorrect?

Was this a 4 port or 2 port HPT controller? Keep in mind, two disks on
the same IDE channel severely degrades performance, *especially* with
RAID.

-- 
Mvh,
André Tomt
andre@tomt.net