|I (a single user) am running N separate MPI applications doing 1 to N broadcasts over PVM, each MPI application is started on each machine simultaneously by PVM - the reasons are back in the post history.|
The problem is that they somehow collide - yes I know this should not happen, the question is why.
--- On Wed, 11/8/10, Richard Treumann <email@example.com> wrote:
From: Richard Treumann <firstname.lastname@example.org>
Subject: Re: [OMPI users] MPI_Bcast issue
To: "Open MPI Users" <email@example.com>
Received: Wednesday, 11 August, 2010, 11:34 PM
I am confused about using multiple,
concurrent mpirun operations. If there are M uses of mpirun and each
starts N tasks (carried out under pvm or any other way) I would expect
you to have M completely independent MPI jobs with N tasks (processes)
each. You could have some root in each of the M MPI jobs do an MPI_Bcast
to the other N-1) in that job but there is no way in MPI (without using
accept.connect) to get tasks of job 0 to give data to tasks of jobs 1-(m-1).
With M uses of mpirun, you have M worlds
that are forever isolated from the other M-1 worlds (again, unless you
In what sense are you treating this
as an single MxN application? ( I use M & N to keep them distinct.
I assume if M == N, we have your case)
Dick Treumann - MPI Team
IBM Systems & Technology Group
Dept X2ZA / MS P963 -- 2455 South Road -- Poughkeepsie, NY 12601
Tele (845) 433-7846 Fax (845) 433-8363
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