On Wed, 2014-04-02 at 16:02 -0400, Digimer wrote: > In short, I don't know if there is anything that can sum the > computational power of multiple systems and transparently make it look > like a single super fast machine. My experience says there isn't. Granted I am not an expert in parallel computing, but I work for a supercomputing site. About 15 years ago, high performance computing hit the wall with regard to how fast a single processor can be. We had CRAY computers that used vector processing; that means executing the same instructions on a range of memory words at the same time in one instruction cycle. This means that code like for i = 1,100 do a[i]=a[i]*2 done would execute at the same speed as "x=x*2" (in this admittedly trivial example, you get a factor of 100 speedup). That was a lot easier to program for than multiprocessing, but even that required careful attention when writing code so that it would vectorize and get the performance boost. After single processor computing hit the wall, we and every other HPC site had to go to parallel processing (modern supercomputers have tens of thousands of processors running on thousands of separate nodes). This too requires special coding, so that your program will naturally break up into separate tasks that can be executed in parallel. That is true whether you are talking about using multiple processors on a single machine, or spreading a code over multiple systems. There are MPI libraries to make this task easier, but it is never as simple as "OK, now execute this unmodified code five times as fast using five machines instead of one". How difficult it is to parallelize the code depends, as has already been said here, on the particular application to be parallelized. --Greg -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
