Path: utzoo!mnetor!uunet!husc6!think!ames!oliveb!sun!pepper!cmcmanis
From: cmcmanis%pepper@Sun.COM (Chuck McManis)
Newsgroups: comp.sys.amiga
Subject: Re: A2090 controller
Message-ID: <47683@sun.uucp>
Date: 31 Mar 88 07:18:42 GMT
References: <2911@leo.UUCP>
Sender: news@sun.uucp
Reply-To: cmcmanis@sun.UUCP (Chuck McManis)
Organization: Sun Microsystems, Mountain View
Lines: 25

In article <2911@leo.UUCP> harald@leo.UUCP ( Harald Milne) writes:
->	Another opinion.
-->
->	Owning an A1000 with a Supra Drive 20meg SCSI drive and a
->A2000 with A2090 controller and Seagate 251 drive, I feel somewhat 
->qualified to make the following statements.
->
->	For reasons I can't understand, (and I do understand the reasons
->for SCSI speed improvements) the A2090 seems do better. My A2000 has
->a very snappy response compared to the A1000 with SCSI. With all things
->being equal (like number of top level directories, diskbuffers, etc)
->and things being unequal (SCSI track buffering, average access times)
->this is really strange.

Actually it isn't quite so strange. You see the 2090 is a DMA driven
device, basically it dumps stuff into memory for you automatically.
The Supra (and many other SCSI interfaces for the 1000) are interrupt
driven i/o, which is slower. Something else to look forward to, the
Fast File system is 10 - 50% faster than what you have now. Zooom city
as they say. Basically, it just keeps getting better and better...


--Chuck McManis
uucp: {anywhere}!sun!cmcmanis   BIX: cmcmanis  ARPAnet: cmcmanis@sun.com
These opinions are my own and no one elses, but you knew that didn't you.