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From: Scott Mace <smace@metal-mail.neosoft.com>
Message-Id: <199505082158.PAA00426@metal.ops.neosoft.com>
Subject: Re: Is a 486 fast enough for SCSI?
To: tom@haven.uniserve.com (Tom Samplonius)
Date: Mon, 8 May 1995 15:58:57 -0600 (MDT)
Cc: hackers@FreeBSD.org
In-Reply-To: <Pine.BSF.3.91.950508121705.2024B-100000@haven.uniserve.com> from "Tom Samplonius" at May 8, 95 12:26:33 pm
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> 
> 
>   I've got a AMD486DX4100 with an Adaptec 2940 and two SCSI drives.  When 
> I run iozone on one drive I get about 1.9MB/s, but when I run a iozone on 
> each drive I get about .9 MB/s (roughly half).  Since the SCSI bus runs 
> at 10MB/s per second, the limiting factor appears to be the CPU?  I 
> thought PCI devices required very little CPU time?
> 

The limiting time is the speed of the drive.  I can get over 3megs/sec
with my EISA bt747 and seagate barracuda drives.  And my cpu is only
a 486DX2-66.  I'm never seen a single scsi drive actually do 10MB/sec.

	Scott