Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!usc!sdsu!crash!pnet01!jca
From: jca@pnet01.cts.com (John C. Archambeau)
Newsgroups: comp.os.minix
Subject: Re: minix on the macintosh
Message-ID: <334@crash.cts.com>
Date: 8 Sep 89 04:16:08 GMT
Sender: root@crash.cts.com
Organization: People-Net [pnet01], El Cajon CA
Lines: 31

Minix on a Mac would be a very lousy platform.  Reason being that Macs don't
have a notion what DMA is.  Run Minix on a Mac Plus and I guarrantee you it
will perform worse than a 4.77 XT with a Western Digital controller w/DMA. 

Without DMA support in hardware, porting Minix to a Mac would be pointless. 
But one thing that does come to mind.  If the Radius Accelerators support DMA
with hard drive I/O, then the platform to a Mac with a Radius Accelerator
would be worthwhile.

I have heard from very knowledgeable people who know that Mac well that there
is no DMA support unless you go to one of the '030 based machines and put in a
card with the DMA controller.  I suspect that my sources are correct because
of my observations of how our TOPS network at my place of employment performs.

If the accelerators out there support DMA fully, then the Minix port would be
worthwhile, but then again...the Mac wasn't designed to run a time-sharing OS
or to 'multitask' to begin with.  If you want a Mac like environment with
Unix, then you go out and buy a Sun workstation, you stay away from the Mac. 
Even the Mac II's with the '030 in them aren't speed daemons.

If you want Minix, an IBM clone/compatable or Atari ST is worth it in my
opinion.  The Mac is a beast of a machine to write standalone system software
for.

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