> Joseph Mack writes: > > > I expect everyone here knows all this. How is everyone going > > to program the quadcore machines? > > We used OpenMP on the node and MPI between the nodes. It's ugly and > horrendous to look at or comprehend. The only saving grace is that our > source code is serial plus custom directives and we have tools to > generate OpenMP or calls to a MPI based library or both. So we put all > the difficult stuff in the directives. We don't have any SMP nodes > anymore so it will take some time to resurrect that ability. > > Using straight MPI is the lowest common denominator and simplest, but > doesn't use the machine very efficiently. I think it'll only get worse > with more cores. > > I'd be interested in your experience and what you find out. > > Matt > >
I don't know the answer to this, but what about MPI implementations which enable local host optimization automatically? For example, MPICH, Intel MPI, and HP-MPI among others all do so if asked. Is running a program using OpenMP on a SMP/multi-core box more efficient that an MPI code with an implementation using localhost optimization? Joseph _______________________________________________ Beowulf mailing list, [email protected] To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
