Re: PTP Communication problems when using a single process

At 04:50 AM 3/18/2004, Eylul Ince wrote:
>
>Hi,
>
>I am confused about the the following. Any help'd be
>appreciated.
>
>I have a very simple program:
>
>##########################
>int id, ntasks, tag=100;
>int msg[2];
>
>MPI::Init(argc, argv);
>ntasks = MPI::COMM_WORLD.Get_size();
>id = MPI::COMM_WORLD.Get_rank();
>
>msg[0] = id;
>msg[1] = ntasks;
>
>MPI::COMM_WORLD.Send(msg, 2, MPI::INT, 0, tag);
>MPI::COMM_WORLD.Recv(msg, 2, MPI::INT, 0, tag);
>
>MPI::Finalize();
>###############################
>
>The problem is that the same process is both sender
>and receiver (I know that it does not make sense too
>much, but I need to test something with this code).
>
>If I use ethernet (ch_p4), it works fine.  But running
>it on myri core-dumps during receiving.
>
>Does anybody have an idea what's happening?

It shouldn't dump core, but it would be valid for an MPI implementation to 
hang here.

To check on the core dump, does it help to pass an MPI::Status to Recv?

Bill