This should not happen. Typically, Intra node communication latency are way way cheaper than inter node. Can you please tell us how u ran your application ? Thanks
-- Sent from my iPhone On Jun 1, 2012, at 7:34 AM, Mudassar Majeed <mudassar...@yahoo.com> wrote: > Dear MPI people, > Can someone tell me why MPI_Ssend takes more > time when two MPI processes are on same node ...... ?? the same two processes > on different nodes take much less time for the same message exchange. I am > using a supercomputing center and this happens. I was writing an algorithm to > reduce the across node communication. But now I found that across node > communication is cheaper than communication within a node (with 8 cores on > each node). > > best regards, > > Mudassar > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users
