Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!munnari.oz.au!uniwa!swanee!zeus!robert From: robert@zeus.ee.uwa.oz.au (Roberto Togneri) Newsgroups: comp.sys.transputer,uwa.test Subject: T800 - how fast are they really? Summary: T800 - how fast are they really? Keywords: parallel transputer Message-ID: Date: 5 Nov 90 05:46:29 GMT Sender: news@swanee.ee.uwa.oz Organization: Elec Eng, Univ of Western Australia Lines: 25 I have been experimenting with our transputers to allow faster execution times to be achieved over our IRIS workstations. The personal IRISes are rated at 10 MIPS and use a MIPS CPU including the floating point unit. The transputers are a mix of t800d and t800c chips (and a T414 root) running at 20 Mhz and I am lead to believe that they can achieve 10 MIPS. With a 10 t800 transputer array then I expect to go at least 7 times faster than the IRISes. Well all I've been able to get is 1.5 times faster! I use the optimiser on the IRIS compiler (cc -O prog.c) and am using 3L parallel C (v2.0) for the transputers (t8c prog.c). Thinking that my program was at fault (parallel programming ain't easy) I ran two similar programs on the IRIS and a t800. And lo! The IRIS was 5 times faster. Is this expected? How fast are the t800's? How good is the compiler? What am I doing wrong? If somebody can shed some light on this I would really appreciate it. -- Dr. Roberto Togneri Dept. of EE Engineering Phone: +61-9-380-2535 The University of Western Australia Fax: +61-9-380-1065 NEDLANDS WA 6009 Email: robert@swanee.ee.uwa.oz.au