Python

Cray Python was built with the GNU compilers.

mpi4py

• Error messages about PMPI_Mprobe: Early versions of the Cassini provider don't support the MPI MProbe functions. The workaround is to set

  export MPI4PY_RC_RECV_MPROBE='False'
  

• mpi4py complains with

  Attempting to use an MPI routine before initializing MPICH
  

  According to the course materials it could be related to mpi4py being built with GCC, and the workaround is to use

  LD_PRELOAD=/opt/cray/pe/lib64/libmpi_gnu_91.so