Path: utzoo!attcan!uunet!convex!texsun!pitstop!sun!amdcad!crackle!tim
From: tim@crackle.amd.com (Tim Olson)
Newsgroups: comp.arch
Subject: Re: What kinds of problems...
Message-ID: <24910@amdcad.AMD.COM>
Date: 19 Mar 89 22:33:58 GMT
References: <471@estevax.UUCP> <15347@winchester.mips.COM> <7137@phoenix.Princeton.EDU> <24888@amdcad.AMD.COM> <11458@cgl.ucsf.EDU>
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In article <11458@cgl.ucsf.EDU> seibel@cgl.ucsf.edu (George Seibel) writes:
| In article <24888@amdcad.AMD.COM> tim@amd.com (Tim Olson) writes:
| |In article <7137@phoenix.Princeton.EDU> mbkennel@phoenix.Princeton.EDU (Matthew B. Kennel) writes:
| || Are there any really big jobs out there that are seriously bounded
| || by integer CPU performance?  (Excuse me, but I'm probably very naive)
| |
| |Oh, yes.  Our machines here are loaded with simulations to do.  We could
| |always use more integer performance.
| 
| What kinds of simulations are these?   I don't doubt that they exist,
| I've just never seen one and am genuinely curious.   Would there be any
| commercial interest in a really fast integer box that had only fair
| floating pt performance?

To design our next-generation processors, we need to examine a number of
architectural tradeoffs and see how they affect overall performance.  To
do this, we use an Architectural Simulator (simulates the processor at
the register-transfer level), make the appropriate changes to it, and
run a suite of benchmarks.

The simulator is heavily instrumented to collect a wide range of
statistics, and runs about 1600 simulated cycles per second on a Sun
4/110.  The only floating-point in the simulator is calculating and
printing some of the statistics at the end of the simulation --
everything else is purely integer.


	-- Tim Olson
	Advanced Micro Devices
	(tim@amd.com)