I have a four-node quad core cluster. I am running OpenMPI (version 1.4.2) jobs with Torque (version 2.4.8). I can submit jobs using
#PBS -lnodes=4:ppn=4
And 16 processes are launched. However if I use
#PBS -lnodes=4:ppn=1
or
#PBS -lnodes=4
The call to MPI_Init is succesful, but the call to
MPI_Comm_size(MPI_COMM_WORLD, &mpi_nprocs)
hangs and never returns.
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