This is an interesting question. As multi-core become more pervasive this will beg the bigger question. What is cluster? Recall, there is a design called a "constellation" where the number of cores on the nodes is greater than the number of nodes. Therefore if you have four 8-core nodes (32 cores total) connected with IB, you have a "constellation cluster". The "parallelism" may be more in the nodes, than between the nodes.
In any case, you have a pile of cores how do you program them? Fortunately MPI will work on multi-core and across nodes. For the most part, OpenMP and threads only work on single motherboards. I investigated this idea (MPI vs OpenMP on a single multi-core node) and wrote up my results here: http://www.linux-mag.com/id/4608 Of course, there is a need for more testing with different compilers and hardware platforms, but it is clear, MPI on multi-core SMP is not necessarily a bad idea, in some cases it is a good idea. There are some who may argue this, but data points are really the only thing worth discussing. I'll have some new hardware in May and I plan on re-running the tests mentioned in the article. -- Doug > is it possible to have a single multicored machine as a cluster? > > -- > Jonathan Aquilina > > -- > This message has been scanned for viruses and > dangerous content by MailScanner, and is > believed to be clean. > > _______________________________________________ > Beowulf mailing list, [email protected] sponsored by Penguin Computing > To change your subscription (digest mode or unsubscribe) visit > http://www.beowulf.org/mailman/listinfo/beowulf > -- Doug -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. _______________________________________________ Beowulf mailing list, [email protected] sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
