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With the new OS version comes a small problem with the standard openmpi
implementation. With "module load mpi/openmpi-x86_64" you use the standard openmpi
from centos. If your job is crashing with "SEGVAULT" you have to add a
parameter for your mpirun.  If possible use "ucx" as this is the new standard protokoll in MPI.

There are two ways to achieve  this:

  1. You can  create a file in your homedirectory with one line "pml=ob1"
    or "pml=ucx"

    # mkdir ~/.openmpi
    # vi ~/.openmpi/mca-params.conf
    # cat ~/.openmpi/mca-params.conf
    pml=ob1
    
  2. You can add the parameter to your mpirun commando for example "mpirun --mca pml ob1 foo"
    or "mpirun --mca pml ucx foo"
    (foo := name of your programm)


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