[Pympi-users] Asynchronous communcation

[<oli...@en...>]

Hello,

I'd like to perform non blocking asynchronous communications between
different MPI processus. 0 send to 1 and 2 some message at some given
times while 1 and 2 are busy (doing some time consuming operation like
sleeping for instance ;). However they check what is in their mail box
from time to time.

To achieve this task I used mpi.isend and mpi.recv but according to the
following I should have made a msitake somewhere because non of the sent
messages never arrive to 1 or 2.

What have i done wrong?

Thanks

Olivier


PS: Here is the sample program testMPI.py:

<quote>
#!/usr/bin/env python

import mpi, time

if mpi.rank == 0:
    print '** 0 : sleeping ...'
    time.sleep(3.0)
    print '** 0 : sending hello to %d ...'%1
    request1 = mpi.isend('Hello 1', 1)
    print '** 0 : sleeping ...'
    time.sleep(4.0)
    print '** 0 : sending hello to %d ...'%2
    request2 = mpi.isend('Hello 2', 2)
    while (not request1) or (not request2):
        pass
    print '** 0 : sequence finished'

else:
    msg = None
    while msg == None:
        print '**', mpi.rank, ': sleeping 1s ...'
        time.sleep(1.0)
        print '**', mpi.rank, ': receiving...'
        reception = mpi.irecv(0)
        if reception:
            msg = reception.message
            print '**', mpi.rank, ':', 'received :', msg

</quote>

And here is the output (interrupted by keyboard ^C stroke)

sync17% mpirun -np 3 -machinefile machines pyMPI testMPI.py
** 1 : sleeping 1s ...
** 0 : sleeping ...
** 2 : sleeping 1s ...
** 1 : receiving...
** 1 : sleeping 1s ...
** 2 : receiving...
** 2 : sleeping 1s ...
** 1 : receiving...
** 1 : sleeping 1s ...
** 2 : receiving...
** 2 : sleeping 1s ...
** 1 : receiving...
** 1 : sleeping 1s ...
** 2 : receiving...
** 2 : sleeping 1s ...
** 0 : sending hello to 1 ...
** 0 : sleeping ...
** 1 : receiving...
** 1 : sleeping 1s ...
** 2 : receiving...
** 2 : sleeping 1s ...
** 1 : receiving...
** 1 : sleeping 1s ...
** 2 : receiving...
** 2 : sleeping 1s ...
** 1 : receiving...
** 1 : sleeping 1s ...
** 2 : receiving...
** 2 : sleeping 1s ...
** 1 : receiving...
** 1 : sleeping 1s ...
** 2 : receiving...
** 2 : sleeping 1s ...
** 0 : sending hello to 2 ...
** 1 : receiving...
** 1 : sleeping 1s ...
** 2 : receiving...
** 2 : sleeping 1s ...
** 1 : receiving...
** 1 : sleeping 1s ...
** 2 : receiving...
** 2 : sleeping 1s ...
** 1 : receiving...
** 1 : sleeping 1s ...
** 2 : receiving...
** 2 : sleeping 1s ...
** 1 : receiving...
** 1 : sleeping 1s ...
** 2 : receiving...
** 2 : sleeping 1s ...
bm_list_20012:  p4_error: interrupt SIGINT: 2
Killed by signal 2.
Killed by signal 2.
p0_20011:  p4_error: interrupt SIGINT: 2