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Date: Thu, 7 Aug 1997 23:22:25 -0700 (PDT)
From: Tom <tom@uniserve.com>
To: Atipa <freebsd@atipa.com>
cc: "John S. Dyson" <toor@dyson.iquest.net>, dyson@FreeBSD.ORG,
        ggm@connect.com.au, current@FreeBSD.ORG
Subject: Re: IDE vs SCSI was: flags 80ff works (like anybody doubted it)
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On Thu, 7 Aug 1997, Atipa wrote:

> My thoughts exactly. Depending on the card and driver level, SCSI is 
> actually slower in many cases. Similar IDE drives outperformed SCSIs 

  Many cases?  Only in command overhead.

...
> > This is the result of my Hawk, SCSI drive, with an NCR 815 interface: 
> > 
> > Command overhead is 845 usec (time_4096 = 2071, time_8192 = 3297)
> > transfer speed is 3.34201e+06 bytes/sec
> > 
> > dd if=/dev/rsd0 of=/dev/null count=1600 bs=64k
> > 1600+0 records in
> > 1600+0 records out
> > 104857600 bytes transferred in 27.336979 secs (3835742 bytes/sec)

  Hehe, I can do the above dd at 8738133 bytes/sec, on a NCR 810
(narrow!), with a Seagate Barracuda.  Try to find a IDE drive that can do
that.  This is only a P120.

Tom