Hi Gabriele Shouldn't you reverse the order of your send and recv from MPI_Irecv(buffer_recv, bufferLen, MPI_INT, recv_to, tag, MPI_COMM_WORLD, &request); MPI_Send(buffer_send, bufferLen, MPI_INT, send_to, tag, MPI_COMM_WORLD);
to MPI_Send(buffer_send, bufferLen, MPI_INT, send_to, tag, MPI_COMM_WORLD); MPI_Irecv(buffer_recv, bufferLen, MPI_INT, recv_to, tag, MPI_COMM_WORLD, &request); ? Jody On Thu, Feb 5, 2009 at 11:37 AM, Gabriele Fatigati <g.fatig...@cineca.it> wrote: > Dear OpenMPI developer, > i have found a very strange behaviour of MPI_Test. I'm using OpenMPI > 1.2 over Infiniband interconnection net. > > I've tried to implement net check with a series of MPI_Irecv and > MPI_Send beetwen processors, testing with MPI_Wait the end of Irecv. > For strange reasons, i've noted that, when i launch the test in one > node, it works well. If i launch over 2 or more procs over different > nodes, MPI_Test fails many time before to tell that the IRecv is > finished. > > I've tried that it fails also after one minutes, with very small > buffer( less than eager limit). It's impossible that the communication > is pending after one minutes, with 10 integer sended. To solve this, > I need to implement a loop over MPI_Test, and only after 3 or 4 > MPI_Test it returns that IRecv finished successful. Is it possible > that MPI_Test needs to call many time also if the communication is > already finished? > > In attach you have my simple C test program. > > Thanks in advance. > > -- > Ing. Gabriele Fatigati > > Parallel programmer > > CINECA Systems & Tecnologies Department > > Supercomputing Group > > Via Magnanelli 6/3, Casalecchio di Reno (BO) Italy > > www.cineca.it Tel: +39 051 6171722 > > g.fatigati [AT] cineca.it > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users >