rae@alice.UucP (Rae McLellan) (03/24/86)
John Mashey suggests: Use cycles/MIPS (normalized to some common unit of work), i.e., try: cycles/MIPS = (clock rate in MHz) / (MIPS rating) But the units seem to be confused. Clock rate in MHz should be Mega-cycles. In any event, the Mega's cancel and you're left with clocks/inst. What are you really trying to say? It's not the best (or worst) #clocks/inst that should be reported, but rather the average #clocks/inst sustained over a significant stretch of code? (please verify this.) I too have been disgruntled with the meaning of MIPS. In particular, the multi-processor types (IBM, NEC, Encore, etc) which trumpet their superior performance as a single MIPS number. Instead of a single MIPS number, I'd like to clarify exactly what is being measured with 3 separate performance metrics: Peak MIPS maximum #inst/second Average MIPS sustained rate over a "reasonable" instruction mix further describing the mix as w/ floating point, w/o, etc. Aggregate MIPS describes the additional performance (however specious) which arise with the extra processors. Let's try to inform, not mislead. Rae McLellan AT&T Bell Laboratories research!rae