Why does Intel favor thin rectangular CPUs?
|
Prev: 128316 Computer Knowledge, Free and alwqays Up to Date 59
Next: Fwd: Different stacks for return addresses and data?
From: Robert Myers on 3 Mar 2010 09:52 On Mar 3, 2:00 am, Terje Mathisen <"terje.mathisen at tmsw.no"> wrote: > Robert Myers wrote: > > Latency that is exposed on the critical path is forever. It isn't > > very often that you *have* to leave latency exposed on the critical > > path. > > Huh? > > In my book "critical path" is nothing but latency. > > > Once again, it is a matter of design choices. > > Please choose to remove all latency limits then! > All the options I know about involve transistors and watts. The design choice is not to expend transistors and watts that way, but making progress would not be, so far as I know, a matter of delivering miracles. Robert.
From: Robert Myers on 3 Mar 2010 10:02 On Mar 3, 6:30 am, "nedbrek" <nedb...(a)yahoo.com> wrote: > Hello all, > > > Did anyone see the comparison between P4 and the latest Nehalem?http://hardware.slashdot.org/article.pl?sid=10/02/16/2212220 > > There is an interesting note at the end: hardware performance has doubled > (at the same frequency), but software performance for similar tasks has > increased less (presumably due to bloatiness). > Actually, that underreports just how bad things are on the software front. As we become ever more reliant on computers, software becomes ever more dodgy and vulnerable to hacks. That trend will continue because people are making money doing business that way. Robert.
From: Robert Myers on 3 Mar 2010 10:10 On Mar 3, 1:40 am, Terje Mathisen <"terje.mathisen at tmsw.no"> wrote: > Robert Myers wrote: > > From that experience, I acquired several permanent prejudices: > > > 1. For scientific/engineering applications, "programmers" should > > either be limited to sorting and labeling output, or (preferably) they > > should be shipped to the antarctic, where they could be sent, one at a > > time, to check the temperature gauge a quarter mile from the main > > camp. > > > 2. No sane computational physicist should imagine that even a thorough > > knowledge of FORTRAN was adequate preparation for getting things done. > > > 3. Computer architects are generally completely out of touch with > > reality. > > Hmmm... let's see... > > 1. I'm a programmer, but otoh I do like xc skiing and I would love to be > able to spend a season in Antarctica. > > 2. I learned programming on a Fortran 2 compiler, '27H' Hollerith text > constants and all. I've done CFC (computational fluid chemistry) > optimization, doubling the simulation speed. > > 3. Yes, my employer tend to put me in the 'Architect' role on the staff > diagrams. > > So Robert, do I satisfy your prejudices? > :-) > Prejudices are just prejudices, and I labeled mine as such. The point about Fortran is that you really have to know what the computer is doing in considerably more detail than the language interface describes. I'm sure that many real, and very talented architects and programmers are frustrated at how priorities are set. Robert.
From: nmm1 on 3 Mar 2010 10:17 In article <1d917fa8-0be1-47ba-8863-4a10d08173c5(a)t20g2000yqe.googlegroups.com>, Robert Myers <rbmyersusa(a)gmail.com> wrote: >On Mar 3, 1:40=A0am, Terje Mathisen <"terje.mathisen at tmsw.no"> wrote: >> >> So Robert, do I satisfy your prejudices? >> :-) >> >Prejudices are just prejudices, and I labeled mine as such. No, only a few of them. >The point about Fortran is that you really have to know what the >computer is doing in considerably more detail than the language >interface describes. Eh? If you were to say that about programming in general, it would be debatable. You might, JUST, be able to say that about Fortran versus Python or Java. But it's a bizarre statement to make about Fortran without qualification. What do you mean by it? Regards, Nick Maclaren.
From: Tim McCaffrey on 3 Mar 2010 11:17
In article <6f6034e6-e6e7-46b4-8b74-668898d018f1(a)19g2000yqu.googlegroups.com>, rbmyersusa(a)gmail.com says... > >On Mar 3, 12:54=A0am, timcaff...(a)aol.com (Tim McCaffrey) wrote: >> In article >> <667e9f6b-6170-4d0e-8a68-06cdfc897...(a)g11g2000yqe.googlegroups.com>, >> rbmyers...(a)gmail.com says... >> >> >From that experience, I acquired several permanent prejudices: >> >> >1. For scientific/engineering applications, "programmers" should >> >either be limited to sorting and labeling output, or (preferably) they >> >should be shipped to the antarctic, where they could be sent, one at a >> >time, to check the temperature gauge a quarter mile from the main >> >camp. >> >> >2. No sane computational physicist should imagine that even a thorough >> >knowledge of FORTRAN was adequate preparation for getting things done. >> >> >3. Computer architects are generally completely out of touch with >> >reality. >> >> >Do anything you like, but please never show respect for Seymour Cray, >> >including misspelling his name. >> >> >Robert. >> >> I certaintly didn't intend to misspell his name. >> >> Hey, I tell you what, you don't tell me who I should show respect for and= > I >> won't bother to point out that you ended up recreating a design that you >> say you despise, OK? >> >> And I'm also sorry that wherever you were, it didn't have competent >> programmers (or, apparently, physicists). >> >> MSU physicists designed two different cyclotrons using the CDC machines. >> >To be clear, Tim, I don't think I've invented anything. There are >some obvious things that you can do with memory, some of which I >suggested in this forum long ago. > >As to Seymour, he gets dissed a lot, and I don't hear many people >objecting. Well, I object. So far as I know, he never signed any >consent decrees, practically invented the supercomputer brand which is >now used to label warehouses full of racks, and understood the needs >of computational physicists in a way that most computer architects >(including, most glaringly, the ones who work at the bomb labs) just >don't. > >Robert. > >Robert. > Ok, now I'm confused. You original post implied to me you did not like Cray or what he did. To be clear myself, I have a great deal of respect for Mr. Cray. Although he made some mistakes, they are really only obvious in hindsight. - Tim |