hui xie wrote: > Thanks very much for all your advice. To be clear, my OS is window > XP. I bought this server last year. It's Dell Precision PWS690. THe > processor is Xeon(TM) CPU 3GHZ, 2G RAM. I am not sure how to check > more details of processor on my computer. But I went to Dell website > and from what I can recall, it seemed that I ordered a Dual-core > Intel Xeon 5160 3GHz, 1333FSB, 4MB L2 Cache, 80watts. > I think from time to time, I will need linear algebra to do things > such as Choleskey Factorization, and matrix inverse etc... At the > same time, I considered myself quite unskilled on building R by > myself. It seems there were lots of details that I can get things > wrong. So if there is an existing ATLAS one on R website that I can > use, I would be very happy to use it to replace the default one. The > reason why I would like to use ATLAS is that R FAQ said : > > "The savings can be appreciable: on a 2.6GHz P4 and a 1000 x 1000 > matrix svd took 16.2 sec with the standard BLAS and 7.8 sec with > ATLAS. Because ATLAS is tuned to a particular chip we can't use it > generally: the optimal routines for a P4 or an Athlon XP are quite > different and neither will run at all on a PII." > > This seems to me an impressive gain to use the correct ATLAS instead > of the default BLAS. I guess my Xeon processor is either a P4 or > Core2Duo, but I am really not sure which one to use. Could you please > offer me some suggestions?
As a Google search tells you, the Xeon 5100 series is Core2 based while 5000 and former CPUs were NetBurst based. Uwe Ligges > Again, many thanks for all your advice! > > Best, > > Hui > > Uwe Ligges <[EMAIL PROTECTED]> wrote: > > Prof Brian Ripley wrote: >> On Tue, 28 Aug 2007, hui xie wrote: >> >>> hi everyone: >>> >>> I have a Dell Server that has a Xeon processor, and I would like >>> to use the best ATLAS posted in the R website. I find that R has >>> ATLAS for core2duo and P4. I am not sure which one of these two >>> is best suited for Xeon processor, or is that neither of these >>> two is good and I should stick with the default one that was >>> installed originally? >> And your OS is? >> >> There are many different 'Xeon' processors with very different >> capabilities. > > ... the earlier similar to P4 and some similar to Core2Duo. You won't > make use of bigger L2/L3 caches in Xeon processors. > >> You really ought to build ATLAS for yourself if numerical linear >> algebra performance matters to you (and it makes little difference >> to most people: I think Uwe Ligges quoted 10% for testing all CRAN >> packages). > > > Right, it depends on what you are really doing. If most time is spend > in certain numerical matrix operations, ATLAS is your friend. In all > other cases, it does not matter so much, as Brian cited correctly. > > Uwe Ligges > > >>> Your advice is very much appreciated! >>> >>> Best, >>> >>> Hui >>> >>> >>> --------------------------------- Park yourself in front of a >>> world of choices in alternative vehicles. >>> >>> [[alternative HTML version deleted]] >>> >>> ______________________________________________ >>> R-help@stat.math.ethz.ch mailing list >>> https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the >>> posting guide http://www.R-project.org/posting-guide.html and >>> provide commented, minimal, self-contained, reproducible code. >> Please do! >> >> > > > > --------------------------------- Yahoo! oneSearch: Finally, mobile > search that gives answers, not web links. ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
