On Dec 11, 2007 2:40 AM, Joe Landman <[EMAIL PROTECTED]> wrote: > Our view has always been use what you are comfortable with, and what you > need. If you need to run across a cluster, use MPI. If you need to run > across a single large memory machine, use OpenMP. > > FWIW: I would suggest learning both. With the advent of many-core > workstations, and accelerator systems with many many cores, programming > these things is more likely to be mediated by a compiler (OpenMP like) > than putting MPI stacks on the Cell SPUs (not enough local scratchpad > ram for it). > > Just my $0.02, and I hope I generated light, and very little heat.
Thanks for your comments. I've seen that OpenMP is much easier to develop with than MPI, which in my experience takes a lot of time to program with due to its low-level nature and complicated side-effects. I would in fact prefer to use implicit parallelism in a high-level language (functional) to program complicated memory architectures. Which doesn't exist in the way I imagine it due to the short-sightedness of programming language people. I don't think that the programmer should be too involved with the exact details of caches, etc. It doesn't make too much sense to me. Back in the day, I learned how to write assembly code that fits in some 256 byte code cache. But how do you do that kind of optimization in a large scale NUMA architecture, what if you move the code to a slightly different architecture? The OpenMP model is superior to old ways of programming shared memory systems (like the awful pthreads), but as the architectures get more complicated I doubt that it will allow the programmers to extract sufficient performance from those systems. BTW, is OpenMP usable with the Cell processor on the Playstation 3? I wondered. Best, -- Eray Ozkural, PhD candidate. Comp. Sci. Dept., Bilkent University, Ankara http://www.cs.bilkent.edu.tr/~erayo Malfunct: http://myspace.com/malfunct ai-philosophy: http://groups.yahoo.com/group/ai-philosophy _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
