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From: ddt@walt.cc.utexas.edu (David Taylor)
Newsgroups: comp.arch
Subject: Re: SPECmarks for RS/6000 systems - lies???
Message-ID: <37935@ut-emx.uucp>
Date: 5 Oct 90 17:19:24 GMT
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Reply-To: ddt@walt.cc.utexas.edu (David Taylor)
Organization: The University of Texas at Austin, Austin, Texas
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It would be interesting to know WHICH benchmarks are hard to duplicate.
My guess is that 70% of them were reproducable and the 2 or 3
easily vectorizable ones (tomcatv, dasa7, etc) were not.  And which
release are we talking about here?

The RS/6000 is a poor candidate for the SPECmark anyway, because it's
strengths lie in just a couple of instructions exploitable in some
programs.  The figures from those benchmarks seriously skew the SPECmark.
Remember, it's based on the geometric mean which doesn't reflect performance
well for poorly distributed benchmark performances.

I think that if you wanted a realistic evaluation of the RS/6000, it
would be safe to say that it will behave much as it did for the benchmarks
like gcc, espresso, and spice2g6, and that for some vectorizable programs
it will run several times faster IF the compiler can interpret them
correctly.

	=-ddt->