Xref: utzoo comp.arch:10656 comp.misc:6562 Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!gatech!uflorida!rex!ukma!xanth!ames!vsi1!wyse!mips!mash From: mash@mips.COM (John Mashey) Newsgroups: comp.arch,comp.misc Subject: Re: Info on DSP chips Message-ID: <23379@winchester.mips.COM> Date: 15 Jul 89 14:29:21 GMT References: <337@venus.iotek.UUCP> Reply-To: mash@mips.COM (John Mashey) Organization: MIPS Computer Systems, Inc. Lines: 36 In article <337@venus.iotek.UUCP> garyb@iotek.UUCP (Gary R. Burrell) writes: >IEEE Micro December 1988 > > A Special Issue on DSP processors, contains detailed articles >on the TMS320C30, DSP32c and DSP96002. These are fairly good articles >about the various DSP processors. The only part of the issue I really >question is the editors afterword in which they come up with some >amazing figures for Linpack ratings of the TMS320C30 (20 MFLOPS) and >DSP96000 (30 MFLOPS). I question these ratings as most supercomputers >only get about 1/10 of there peak performance rating on the LINPACK >benchmark. The chips may do better than that but I for one would like >to see some real numbers using real systems and real compilers. (Can >anyone provide these) I'll be surprised if these chips get anywhere >near these figures on the LINPACK benchmark, I don't doubt that they >can obtain these performances and better on multiply/accumulate >benchmarks. I'm out of town, so I don't have that issue handy. I conjecture that what they must mean is the inner-loop timing for the standard LINPACK code, but with zero-wait-state memory, i.e., something not particularly buildable. To be fair, it is not unreasonable to quote such numbers, if they are clearly labeled as such, because a chip vendor can't control what they're put into, although it would be more meaningful to quotethem with a specified memory system of course. (What is unreasonable, I think, is to quote such numbers, and compare them to measured numbers on real systems built with real memory :-) moral: there are as many flavors of mflops as there are of mips-ratings; if you compare apples and oranges too often you'll go bananas. -- -john mashey DISCLAIMER: UUCP: {ames,decwrl,prls,pyramid}!mips!mash OR mash@mips.com DDD: 408-991-0253 or 408-720-1700, x253 USPS: MIPS Computer Systems, 930 E. Arques, Sunnyvale, CA 94086