Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uflorida!gatech!gitpyr!loligo!mccalpin
From: mccalpin@loligo.uucp (John McCalpin)
Newsgroups: comp.sys.next
Subject: Re: Selling through Businessland
Message-ID: <7780@pyr.gatech.EDU>
Date: 30 Mar 89 19:32:30 GMT
References: <1554@neoucom.UUCP> <121@dg.dg.com> <689@garcon.cso.uiuc.edu>
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Reply-To: mccalpin@loligo.UUCP (John McCalpin)
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In article <689@garcon> dorner@pequod.cso.uiuc.edu (Steve Dorner) writes:
>Don't get me wrong; I'm not saying an 88000 isn't faster than a 68030 on
>real work; I really don't know.  But the obvious calculation of
>	    17MIPS / 5MIPS = 3.4 times faster
>is wrong, isn't it?  Or is that 17 MIPS figure normalized to VAX MIPS?
>Steve Dorner, U of Illinois Computing Services Office

The ratio of 3.4 is not unrealistic for this comparison.  The ratio of
floating-point speeds might be significantly higher.  Of course, much
of what you do on a computer is I/O bound anyway - like compiling programs
and such.  It is also complicated by the fact that software always gets
more complicated on the faster machines, so speedups are sublinear.
An 88000-based machine will feel more responsive than a similarly
designed 68030-based machine, but it won't *feel* like a factor of 3+
except for CPU-intensive tasks.
----------------------   John D. McCalpin   ------------------------
Dept of Oceanography & Supercomputer Computations Research Institute
mccalpin@masig1.ocean.fsu.edu		mccalpin@nu.cs.fsu.edu
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