Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!usc!snorkelwacker!bloom-beacon!eru!luth!sunic!liuida!prosys!ath From: ath@prosys.se (Anders Thulin) Newsgroups: comp.misc Subject: Re: Acronyms. Is is `1 MIP' or `1 MIPS'? Message-ID: <530@helios.prosys.se> Date: 4 Jul 90 06:38:26 GMT References: <+I84:_@xds13.ferranti.com> <1990Jun27.014943.27951@sq.sq.com> <312@spam.ua.oz> <9007031705.AA04537@stc06.CTD.ORNL.GOV> Organization: Telesoft AB, Teknikringen 2A, S-583 30 Linkoping, Sweden Lines: 28 In article <9007031705.AA04537@stc06.CTD.ORNL.GOV> de5@ornl.gov (Dave Sill) writes: >In article <312@spam.ua.oz> wvenable@spam.ua.oz (Bill Venables) writes: >> >> [ ... Question about MIPS ... ] > >Ooh, good questions. First, the reference MIPS standard is indeed the >11/780. Someone, probably DEC, claimed 1 MIPS for the 780. Whether >or not it actually runs at 1 MIPS I have no idea. I always thought it was the other way around: DEC described the performance of their machines in terms of 11/780 performance, which was known to be a 1 MIPS machine (I think DEC claimed this). This confused MIPS with VUP (VAX Units of Performance). One way of getting a true measure of a processors MIPS is to hook into the harware and count the number of clock cycles 'consumed' during x seconds. Knowing the clock cycle timing and the average number of clock cycles per (dynamic) instruction it is easy to get the MIPS rating. In two papers on VAX hardware, published by DEC engineers, it was2 possible to find these values for VAX 11/780 and another machine - I forget which. A little calculation showed that the VAX 11/780 is/was a 0.47 MIPS machine. -- Anders Thulin ath@prosys.se {uunet,mcsun}!sunic!prosys!ath Telesoft Europe AB, Teknikringen 2B, S-583 30 Linkoping, Sweden