Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!rutgers!labrea!decwrl!pyramid!prls!mips!mash From: mash@mips.UUCP (John Mashey) Newsgroups: comp.sys.nsc.32k Subject: Re: what's next??? Message-ID: <585@winchester.UUCP> Date: Tue, 11-Aug-87 04:00:32 EDT Article-I.D.: winchest.585 Posted: Tue Aug 11 04:00:32 1987 Date-Received: Tue, 18-Aug-87 02:59:35 EDT References: <167@unsvax.UUCP> <4538@nsc.nsc.com> <25238@sun.uucp> Reply-To: mash@winchester.UUCP (John Mashey) Organization: MIPS Computer Systems, Sunnyvale, CA Lines: 26 In article <25238@sun.uucp> david@sun.uucp (David DiGiacomo) writes: > ...it == 532.... >Is it really faster than the 68030? The vague numbers I have seen seem to >indicate otherwise, and the 68030 seems to be somewhat closer to sampling. In order to make a comparison, are there any useful numbers available for the 68030? I've seeen recent Moto claims that the 030 is 5.5mips at 16MHz, and 7mips at 20MHz; I'm not sure what flavor of mips those are. They don't exactly seem like VAX-mips: that would give about 2.9 cycles/vmip, which is almost twice as good as the current best 68020 number I know [ 4 vmips Sun-3/2000, 25MHz, no-wait-state 64K virtual writeback cache, 64-bit bus, i.e., aggressive, well-designed memory system, but still needs >6 cycles/vmip]. It's hard to see how the 1-cyle reduction in bus cycles, plus the on-chip data cache [whose net benefit is unclear] halve the cycles/mips. It seems that a 68030 is a reasonable way to build a cheaper lower-speed system [i.e., a cacheless 3-mips design], in that it has an MMU, and may get some mileage from the caches. It's not instantly obvious why a 20MHz 030 is much faster than the 4mips Sun-3 [4.5mips, maybe]. Presumably clock rates will improve. Were those the nubmers you ahd in mind? Does anybody have any other estimates that have some numbers attached? -- -john mashey DISCLAIMER: UUCP: {decvax,ucbvax,ihnp4}!decwrl!mips!mash OR mash@mips.com DDD: 408-991-0253 or 408-720-1700, x253 USPS: MIPS Computer Systems, 930 E. Arques, Sunnyvale, CA 94086