Path: utzoo!mnetor!tmsoft!torsqnt!news-server.csri.toronto.edu!bonnie.concordia.ca!clyde.concordia.ca!nstn.ns.ca!news.cs.indiana.edu!ux1.cso.uiuc.edu!uxa.cso.uiuc.edu!dawg6844 From: dawg6844@uxa.cso.uiuc.edu () Newsgroups: comp.sys.mac.system Subject: Re: How many MIPS is a Mac? Message-ID: <1991Feb18.175217.13157@ux1.cso.uiuc.edu> Date: 18 Feb 91 17:52:17 GMT References: <1991Feb18.160733.20724@macc.wisc.edu> Sender: news@ux1.cso.uiuc.edu (News) Organization: University of Illinois at Urbana Lines: 79 dhoyman@vms.macc.wisc.edu writes: >An earlier posting asked for the MIPS rating of a Mac and later postings >have discussed the appropriateness of MIPS and FLOPS (unfortunately I have >lost those, so I cannot post a followup). >While I would agree that one cannot compare MIPS directly, the Dhystone >benchmark is often used as a measure of MIPS with the conversion factor >of 1750 Dhrystone/s = 1 MIPS. However, Dhrystone is actually measuring >the number of passes thru a loop, not actual MIPS. Thus, one can compare >Dhrystones/s on different machines. This is in a sense a measure of raw >horsepower, integer performance. Along with integer performance, Dhrystone >is also compiler and OS dependant, although it was constructed so as to >minimize this variability. For a complete discussion of the Dhrystone see >The Communications of the ACM Vol 27, No 10, 10/84 pg. 1013. >With this in mind, allow me to post some Dhyrstone timings I have obtained >on various machines. I used the Dhystone 1.1 written in C. On the Mac I >built a single version with Think C. On Dos I used Turbo C. On the Unix/Vms >systems I used the vendor's C. >Computer O/S Dhrystones/sec > >Cray Y-MP UNICOS 16000 >Zentith 386 33Mz MS-DOS 8333 >Gateway 386 33Mz MS-DOS 8333 >VAX 6420 VMS 7149 >Mac IIci Macintosh 7145 >Sequent Unix 3699 >Mac IIcx Macintosh 3500 >VAX 3200 VMS 2941 >Mac II Macintosh 2777 >AT&T 6386 MS-DOS 2631 >AT&T 3B2 600 Unix System V 1785 >MicroVAX II Ultrix 1077 >Mac SE Macintosh 877 >VAXstation II VMS 862 >Mac Plus Macintosh 735 >Zenith 8086 10Mz MS-DOS 476 >Sorry for the poor formatting, I had this on an Excel spreadsheet. I have >run this on a Sun SparcStation, but I think the number is way too low. I >would also draw your attention to the Cray number. Remember that this is >for INTEGER performance. If we would run the Whetstone or some other >floating point benchmark, the Cray would show a BIG advantage. >Actually, I only take this with a grain of salt. The only comparisons >that I really believe are application oriented. See MacWorld March 1991 for >a good comparison of Macs and PC's application speed. >Dirk Herr-Hoyman >UW-Madison, Dept. of Family Medicine and Practice >dhoyman@fammed.wisc.edu >608-262-6368 While these numbers are fun, they unfortunately are not any more informative than MIPS or MFLOPS. Toy programs, and 'benchmarks' like whetstone and drhystone, are really a test of the compiler-writers ingenuity. In fact since the code that whetstone and drhystone execute is so simple and publicly available (it is a simple loop) there have been cases of compilers written to detect whetstone and drhystone loops and perform special optimizations. Again, the only true measure of preformance is execution time of real pro grams. Note that the Cray number above is rather silly, and that the numbers would lead you to believe that the 386's substantially outperfom the IIci, despite studies showing quite the opposite. (using mac vs windows apps performance) I would also be interested in the Sparc number, as the sparc2 here in the lab vastly outperforms any macs and pcs we have. The bottom line is that you cannot possibly compare machines by using only one number, no matter what that number is. Dan Walkowski University of Illinois, Dept. of Computer Science walkowsk@cs.uiuc.edu