Leopold Palomo-Avellaneda wrote: > A Dijous 14 Juny 2007 16:40, M. Edward (Ed) Borasky va escriure: > [...] >> b. You want to develop 64-bit applications > > why? you want to develop applications, that they run in a 32 or 64 system > it's > another thing. Maybe they run "better" or worst, but the final architecture > cannot be a target, I think. Well in my case the "fun" is developing 64-bit multicore applications and maxing out the machine. I'm not doing this with a profit motive as yet, so I don't have a problem with limiting myself to things that will only run in a 64-bit machine and which are tuned for multicore. > > [...] > >> As far as the applications in the Debian pool, or open source in >> general, are concerned, I would first look at large-scale scientific >> computing. And I would start with making sure that you have the Atlas >> (automatically tuned linear algebra subroutines) libraries and their >> BLAS and LAPACK interfaces all tuned up and ready to install on all the >> architectures. The ATLAS team is just about ready to release 3.8 -- they >> are at 3.7.32 at the moment and I think what's in Debian is still 3.6.0. > > ok, but I think that this apps are developed in fortran, and the gfortran is > it sufficient developed to make a good difference? Maybe GSL or MTL ..
I don't do much FORTRAN and even less C. When I want raw speed I program in Forth, and when I want convenience I use R for number crunching, Perl for quick scripting and Ruby for longer-lived scripting projects. > >> The last test I ran on my Athlon64 X2 4200+ (2.2 GHz) got me about 10 >> gigaflops in 32-bit arithmetic and about half of that in 64-bit arithmetic. > > I don't understand that. Are you saying that the 64-bits was really worst > than > 32? It's natural that 64-bit operations would take longer than 32-bit ones. You're moving and adding/multiplying half the number of bits. That's kind of a cheat, though, because only some signal and image processing operations and some iterative particle-based/simulation models work really well in 32-bit arithmetic. Big matrix jobs require 64-bit arithmetic and sometimes more. But you can do a *lot* of physics, signal processing and image processing with a fast 32-bit floating point unit, so it's a useful thing for at least one class of user. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
