OpenMPI

Cray MPICH is the recommended MPI implementation on Alps. However, OpenMPI can be used as an alternative in some cases, with limited support from CSCS.

To use OpenMPI on Alps, it must be built against libfabric with support for the Slingshot 11 network.

Todo

Building OpenMPI for Alps is still work in progress: https://eth-cscs.github.io/cray-network-stack/.