Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!wuarchive!cs.utexas.edu!uunet!cbmvax!martin
From: martin@cbmvax.commodore.com (Martin Hunt)
Newsgroups: comp.sys.amiga
Subject: Re: Amiga competitiveness
Message-ID: <14742@cbmvax.commodore.com>
Date: 30 Sep 90 14:07:34 GMT
References: <90271.190320UH2@psuvm.psu.edu> <420@caslon.cs.arizona.edu> <1091@ucsvc.ucs.unimelb.edu.au>
Reply-To: martin@cbmvax.commodore.com (Martin Hunt)
Organization: Commodore, West Chester, PA
Lines: 56

In article <1091@ucsvc.ucs.unimelb.edu.au> U3364521@ucsvc.ucs.unimelb.edu.au (Lou Cavallo) writes:
>G'day,
>
>CJ> In article <420@caslon.cs.arizona.edu>, cjeffery@cs.arizona.edu
>CJ> (Clinton Jeffery) writes:
>
>CJ> Example #2: an Amiga's hard disk, even with FFS, is *ridiculously* slow
>CJ> 	compared to the _identical_ hard disk running DOS or UNIX/386.  This
>CJ> 	is based on empirical observation doing heavy C compiles on a 2000
>CJ> 	with 1MB ram and a 40 Meg ST-251-1.  Sorry.  I wish it were untrue.
>

First of all, this is NOT true.  An Amiga with a fast controller will
outperform most DOS machines.  FFS is much faster than the Berkeley
filesystem, so I would expect to see it always outperform a Unix
system using similar hardware.


>Clint, could you give the specs behind this claim please?
>
>What was the controller on the DOS or UNIX system?
>What was the controller on the Amiga system?

If you were using an ST251 with a 2090, then it is understandable
if things were a bit slow.

>
>I have seen a Quantum 40 Meg equipped 386 DX apparently out perform (2 Mbits
>per sec benchmark) quoted A2000 Quantum 40 Meg throughputs but the 386 had a
>32 bit buss... {which qualitatively explains its approx 2x throughput over a
>16 bit A2000 buss}.

An A2000 with a Q40 drive and a 2091 controller does about 500000 bytes/sec
or 4 Mbits/sec, twice the speed of the 386 machine.  Since this is well
below the capacity of the bus, bus size is not really an issue.

I have seen Amigas do over 10 Mbits/sec from fast hard drives.

>
>One would naturally assume that such a difference for a comparison b/w any 2
>PC systems should be controller/PCbuss related. For our proper analysis we'd
>need to know the controller specifics.
>
>Are we comparing a 386-SX to an Amiga 2000 which is the closest comparison ?
>{A 386DX with SCSI buss and QuantumHD would be a good comparison to a 3000.}
>
>Moreover as Dave Haynie could attest to, the A2000 Zorro II buss is old news
>in todays terms. The new Zorro III buss hits 20 Mbits/sec (Dave?) and Acorns
>ARM III chipset can hit about 38 Mbits/sec I think (can validate anyone ?).
>
Buss speeds are generally measured in bytes per second. I believe Zorro
III does 20M BYTES/sec.  I don't know about the ARM III, but the chipset
isn't what determines the buss speed.

Martin Hunt                     martin@cbmvax.commodore.com
Network Engineer                {uunet|pyramid|rutgers}!cbmvax!martin