Path: utzoo!utgpu!water!watmath!clyde!rutgers!husc6!endor!reiter From: reiter@endor.harvard.edu (Ehud Reiter) Newsgroups: comp.arch Subject: Connection Machine Message-ID: <3516@husc6.harvard.edu> Date: 10 Dec 87 19:46:48 GMT Sender: news@husc6.harvard.edu Reply-To: reiter@harvard.UUCP (Ehud Reiter) Organization: Aiken Computation Lab Harvard, Cambridge, MA Lines: 25 The Connection Machine is usually presented as 64,000 1-bit SIMD processors hooked up with a hypercube router. However, from talking to a few people who have experience with it (the CM2, not the CM1), I get the impression that many applications basically ignore the 1-bit processors and the hypercube router (which is very slow - it takes 1 ms to send a message), and instead do all their computing with the 2000 Weitek FPU's, and do all their communicating with the "NEWS" system, which basically is a fast 2-D mesh interconnect. That is, the alternative model of the Connection Machine which these applications use is that it is a 2-D mesh of 2000 fast FPU's, backed by 512MB of memory and a very high bandwidth disk I/O system. Like a modern-day version of the Illiac IV, I guess (but one that actually works, unlike the Illiac). To me, anyways, this "Illiac" model seems much more useful (for getting real work done) than the "hypercube" model. My question is, how do people who are running real applications on the CM2 use it? Does anyone who actually has a CM care to comment? I realize that there is one serious application, the news-wire retrieval program, which does use the 1-bit CPU's to do its communicating (although it doesn't use the hypercube router very much) - are there other (commercial) applications which use either the 1-bit CPU's or the hypercube router? Ehud Reiter reiter@harvard (ARPA,BITNET,UUCP) reiter@harvard.harvard.EDU (new ARPA)