From owner-freebsd-scsi  Sun Aug 17 19:19:08 1997
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	id AA19946; Sun, 17 Aug 97 22:18:51 -0400
Date: Sun, 17 Aug 97 22:18:51 -0400
From: curt@kcwc.com (Curt Welch)
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To: Tom Samplonius <tom@sdf.com>
Subject: Re: expected performance with DPT RAID-5...
Cc: scsi@FreeBSD.ORG, curt@kcwc.com
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Tom wrote:
>  If I have 5 Barracuda 4LP 4GB drive (about 8MB/s raw
>  read/write) on a single ultra wide channel on a DPT
>  PM334/UW setup in a RAID-5 array, what kind of
>  sequentional read/write performance should I expect?

Don't know what to expect, but I have a similar config.

I have 5 Quantaum Atlas I 4G (fast wide) drives in a RAID-5
config on one bus of of PM3334UW/2 and 5 Quantum Viking 4.55G
(ultra wide) also in a RAID-5 config on the other bus.  The
system is a 180MHz Pentium Pro with 128MB of memory.  The
DPT has a full 64MB of cache (non ecc).

If you want me to run a test and tell you how it performs
I will.  What type of test would you like to see?

BTW, the system still crashes every few days.  Don't know
for sure if it's probelms with the system, the DPT or the
DPT driver - I'm still working on it.  It was very stable
before installing the DPT and the 10 new drives.

Curt