I have a fortran program which uses MPICH library. At some point of the program rank 0 calls an external program which itself uses OPENMP while other ranks wait in an MPI_BARRIER. My issue is that waiting processes stay at 100% CPU usage. I’d like to be able to use resources from waiting processes to speed-up my OPENMP program running on rank 0.
Is there a way to control busy mode of MPICH ? I’ve seen threads but they mainly concern OPENMPI and not MPICH (e.g. –mca mpi_yield_when_idle 1). I believe I would need the MPICH equivalent of –mca mpi_yield_when_idle 1 but I can’t find it.
Thank you for you help and comments
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