Path: utzoo!attcan!uunet!ficc!peter
From: peter@ficc.uu.net (Peter da Silva)
Newsgroups: comp.arch
Subject: Re: 68020 vs. 68030 speed (was Re: 80486 vs. 68040 code size)
Message-ID: <4229@ficc.uu.net>
Date: 18 May 89 13:51:46 GMT
References: <954@aber-cs.UUCP>
Distribution: eunet,world
Organization: Xenix Support
Lines: 21

In article <954@aber-cs.UUCP>, pcg@aber-cs.UUCP (Piercarlo Grandi) writes:
> Well, the problem is not the AT bus, because virtually all 386 ATs use
> caching and a private 32 bit bus for CPU-memory accesses. CPU bound programs
> on such 386s as I have seen don't have a problem with the AT bus, because
> they do not use it.

True, and known. But the problem is still the AT bus because, in general,
the bottleneck on UNIX tends to be disk. The typical huge disk buffers
help a lot, but it's still a problem.

> I cannot resist saying that given the premises, this really should be a plug
> for the NS 32000 family, not the MC 68000 one. :-) :-).

Probably. I've never had the opportunity to use or even see a 32000-based
machine, unfortunately. Is the problem market timing, the prestige of the
people who started Sun, or what?
-- 
Peter da Silva, Xenix Support, Ferranti International Controls Corporation.

Business: uunet.uu.net!ficc!peter, peter@ficc.uu.net, +1 713 274 5180.
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