mpich-shmem problems

[Miroslav Ruda]

Hello,

  I have problems with mpiexec with mpich-shmem. I'm using mpiexec 0.74,
mpich-1.2.5 and PBSPro 5.2.2 on dual processor linux cluster. When using 
comm=mpich-p4 and mpich-gm, MPI jobs are started as expected. However, with
comm-shmem (and job compiled with mpich configured to use only shmem),
job is started twice (when job is submited to PBS using -l nodes=1:ppn=2)
- mpiexec spawns two tasks while mpirun from mpich starts just one process
(which forks second process later itself).

As a temporary fix, I have modified mpiexec to start only one process when
comm=shmem is used. 

diff mpiexec.c.orig mpiexec.c
420a421,422
>     /* hack, start only one proces when SHMEM is used */
>     if (cl_args->comm == COMM_SHMEM) cl_args->pernode = 1;

Any suggestions?

                   Mirek Ruda