Slash Boxes
NOTE: use Perl; is on undef hiatus. You can read content, but you can't post it. More info will be forthcoming forthcomingly.

All the Perl that's Practical to Extract and Report

use Perl Log In

Log In

[ Create a new account ]

ethan (3163)

  reversethis-{ed. ... rap.nov.olissat}

Being a 25-year old chap living in the western-most town of Germany. Stuying communication and information science and being a huge fan of XS-related things.

Journal of ethan (3163)

Saturday October 25, 2003
06:12 AM


[ #15392 ]

I am currently doing a lab at the Institute for Scientific Computing. It was quite a coincidence that I ended up in this one. Essentially it was the only lab offered this term where I wouldn't have to do boring things such as UML or Java. Instead they promised that it could all be done in C which eventually outweighted my worries that I don't really have a clue about scientific computing (the labs deals with parallelizing numerical mathematics, such as calculating a matrix' eigenvalues).

It turns out that it's real fun. I now have access to an impressive SUN midframe with 96 CPUs. Furthermore, we are only six people overall. The best thing however is that I learnt about MPI. The message passing interface works equally well on a single-CPU machine. Yesterday I compiled and installed MPICH and played quite a bit with it. The amazing thing about it is that it can be used as a quick-n-dirty drop-in replacement for C. Whenever I'd like to write a parallel link-checker, I could probably do it very easily this way. Whenever I want to increase the amount of parallelization, I can say C and my program is distributed over a 1000 processes. MPICH takes care of creating and shutting down the processes properly. The only thing I can't do is changing the number of processes at runtime (unlike I can do with C). But of course, I can still use C in each of the processes if I want to.

The documentation of MPICH is quite good, maybe a little terse in its description of what the various functions do. But I found out that I can simply use the documentation of Parallel::MPI::Simple. It covers the basic functions and explains what they do. From that I can derive all the rest that is needed. This is because the MPI specifications defined a beautiful and very consistent interface. Using it from C is a real pleasure.

The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
More | Login | Reply
Loading... please wait.