Hi Gabriele In OpenMPI 1.3 it doesn't matter: [jody@aim-plankton ~]$ mpirun -np 4 mpi_test5 aim-plankton.uzh.ch: rank 0 : MPI_Test # 0 ok. [3...3] aim-plankton.uzh.ch: rank 1 : MPI_Test # 0 ok. [0...0] aim-plankton.uzh.ch: rank 2 : MPI_Test # 0 ok. [1...1] aim-plankton.uzh.ch: rank 3 : MPI_Test # 0 ok. [2...2] [jody@aim-plankton ~]$ mpirun -np 4 mpi_test5_rev aim-plankton.uzh.ch: rank 1 : MPI_Test # 0 ok. [0...0] aim-plankton.uzh.ch: rank 2 : MPI_Test # 0 ok. [1...1] aim-plankton.uzh.ch: rank 3 : MPI_Test # 0 ok. [2...2] aim-plankton.uzh.ch: rank 0 : MPI_Test # 0 ok. [3...3]
Jody On Thu, Feb 5, 2009 at 11:48 AM, Gabriele Fatigati <g.fatig...@cineca.it> wrote: > Hi Jody, > thanks four your quick reply. But what's the difference? > > 2009/2/5 jody <jody....@gmail.com>: >> 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 >>> >> _______________________________________________ >> users mailing list >> us...@open-mpi.org >> http://www.open-mpi.org/mailman/listinfo.cgi/users >> >> > > > > -- > 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 >
