> From: "Gordon W. Ross" <gwr@mc.com>
> Date: Tue, 23 Jan 96 10:23:53 EST
> To: Chris_G_Demetriou@NIAGARA.NECTAR.CS.CMU.EDU
> Cc: bad@flatlin.ka.sub.org, current-users@netbsd.org
> Subject: Re: NCR Driver Problems
> 
> 
> The "highest performance" argument is questionable.
> Using tagged commands on your SCSI bus eliminates the
> bus arbitration and selection phases between commands,

The biggest win with tagged commands is that you can
issue multiple commands to a target and have the target
do the ordering. The target will do the ordering to
optimize the operations as it's doing head seeks and
crossing platters thus yielding a higher throughput
and minimizing the time due to seeking..

If you want to saturate the SCSI bus, you really want
to implement command chaining..

-brad w.