Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!utgpu!water!watnot!watmath!clyde!rutgers!ames!cit-vax!amdahl!chongo From: chongo@amdahl.UUCP Newsgroups: comp.arch,comp.sys.nsc.32k Subject: Re: the NS32532 Message-ID: <6173@amdahl.UUCP> Date: Sun, 12-Apr-87 17:37:25 EST Article-I.D.: amdahl.6173 Posted: Sun Apr 12 17:37:25 1987 Date-Received: Tue, 14-Apr-87 00:12:45 EST References: <4190@nsc.nsc.com> <6167@amdahl.UUCP> <748@instable.UUCP> Reply-To: chongo@amdahl.UUCP (Landon Curt Noll) Distribution: world Organization: Amdahl Coup, UTS Products Hen house Lines: 61 Xref: utgpu comp.arch:850 comp.sys.nsc.32k:54 In reply to: Message-ID: <4193@nsc.nsc.com> by Roger: >The demo showed the visual affects of what 3x ment. Yes you are correct, >at that same meeting, both set-ups were running at the same clock frequency. The demo did not state this this was a simulation, but rather mislead people into thinking that the 32332 was going to 3x of a 32032. Why do you think some people bitched and moaned when the 32332 was showing a performance increase of less than half that amount? >Yes you are correct, at that same meeting, both set-ups were running at >the same clock frequency. Since the demo was I/O bounded anyway, it would >hardly have mattered if the 32332 were actually 10X faster. True. The 3x performance gain was obtained by slowing down the 32032. The was done was by having the 32032 perform extra work (such as non-optimal I/O). Had been a big sign on the demo saying: "simulated performance", maybe things would have been less misleading. This kind of benchmark (showing raw CPU increase) is somewhat comic when you remember that the selling pitch of "32000 vs 68000" was based on total system performance, discounting MOTs raw-cpu performance. But that seems to all be "water under the melons" now, if you know what I mean. What am I looking/hoping for? Well: * What kind of system thur-put increase will I see in a 32532 vs 32x32? Saying 'going from junk C compilers to normal C compilers', jumping to 15Mhz and a 332 gives you 3x is not the most optimal way to gain performance. For example, if you improve the C compiler on a 32332, then you do the same on a 32032. (your code compat, remember?) The compiler improvement should be factored out. Or, if I have XYZns rams in my system, increasing the clock rate may likely lead to more wait states than more performance. * How soon after the 'on-time project' delivers a working 32532 in samples might I see 19800 Dhrystone systems? * How has NSC changed the way the 532 is being developed/built in order to prevent a repeat of the past problems? Like the 16032G to 32016N problems, lack of NSC 32032 demo system, confusing statements about the 32332 performance, ... * If I go ahead and design a system based on the NS32532, won't I be faced with the problem of building with a chip line that is not as commonly used? That may be an unfair/misleading question. But my point is that customers are going to be seeing x86 ot 680x0 systems up the WAZooo. They might wonder about someone going with a non-common brand... Lets try to direct this discussion away from finger point and more toward what will be, and how it has been improved. Also, I hope the NSC folks have not been offended at my asking pointed questions. Best wishes toward building 19800 Dhrystone systems! chongo /\mp/\ -- [views above shouldn't be viewed as Amdahl views, or as views from Amdahl, or as Amdahl views views, or as views by Mr. Amdahl, or as views from his house]