> -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Geoff Jacobs > > Using OpenMP per node is going to be much less portable and > much more complex to implement. It's better to let your MPI > library handle things the smart way.
At QLogic we're quite familiar with benchmarking with good OpenMP compilers (esp. the PathScale compiler, which used to be part of QLogic) and with various modern MPIs (InfiniPath MPI, MVAPICH, Open MPI, HP-MPI, Scali MPI), and I totally agree with the previous two answers. MPI developers pay a large and increasing amount of performance-tuning attention to the larger core counts, NUMA and SMP issues on cluster nodes. Even if you underwent the large effort to re-code an application for which you had the source to an OpenMP / MPI hybrid approach, it is as likely that you would reduce your application's performance as to improve it. That said, there is continuing interest in the Hybrid approach, and large SMP nodes will keep that interest going. A Google on "Hybrid OpenMP MPI" will provide you with some presentations and papers on recent work in this area. You will find that wins with the Hybrid approach are possible, but it is a lot of work, and by no means required, as you move towards clusters with multi-core CPUs. -Tom > > -- > Geoffrey D. Jacobs > > To have no errors > would be life without meaning > No struggle, no joy > _______________________________________________ > Beowulf mailing list, [email protected] To change your > subscription (digest mode or unsubscribe) visit > http://www.beowulf.org/mailman/listinfo/beowulf > _______________________________________________ Beowulf mailing list, [email protected] To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
