Setting the Intel MPI Interconnect
To use a particular interconnect or interconnect variant, the user must set ANSOFT_MPI_INTERCONNECT and ANSOFT_MPI_INTERCONNECT_VARIANT environment values. For example, if you want to override the default behavior and force the use of Ethernet, you can set the ANSOFT_MPI_INTERCONNECT environment variable to appropriate Ethernet interface name for the job.
Supported options for MPI interconnect with Electronics Desktop based on Intel MPI Versions are described below.
With Intel MPI 2018
- ANSOFT_MPI_INTERCONNECT = mpi-auto-selected | shmem | myri | myrinet | ib | infiniband | default | eth | ethernet | (not set)
-
For Linux ANSOFT_MPI_INTERCONNECT=infiniband | ib, you can set interconnect variant values to:
ANSOFT_MPI_INTERCONNECT_VARIANT = ofed | infinipath | dapl | (not set)
With Intel MPI 2021
The Intel® MPI Library switched from the Open Fabrics Alliance* (OFA) framework to the Open Fabrics Interfaces* (OFI) framework and currently supports libfabric*. The DAPL, TMI, and OFA fabrics are deprecated.[1]
Intel MPI 2021 interconnect selection for Windows
-
ANSOFT_MPI_INTERCONNECT = mpi-auto-selected | shmem | ib | infiniband | default | eth | ethernet | efa | (not set)
By default, MPI vendors use the fastest interconnect by default (typically InfiniBand is faster than Ethernet). To override the default behavior and force the use of specific interconnect, you can set the ANSOFT_MPI_INTERCONNECT.
Intel MPI 2021 interconnect selection for Linux
-
ANSOFT_MPI_INTERCONNECT = mpi-auto-selected | shmem | ib | infiniband | default | eth | ethernet | efa | (not set)
-
For ANSOFT_MPI_INTERCONNECT=infiniband | ib, user can set interconnect variant values to:
ANSOFT_MPI_INTERCONNECT_VARIANT = verbs | mlx
For Linux environments, Intel MPI 2021 requires setting fabric provider variables, FI_PROVIDER, I_MPI_OFI_PROVIDER and FI_TCP_IFACE/FI_VERBS_IFACE (i.e. in case fabric provider is TCP/VERBS respectively) for a successful run. AEDT will set these values based on the available interconnects on Linux. AnsysEM will always prefer ethernet.
[1] https://www.intel.com/content/www/us/en/developer/articles/technical/mpi-library-2019-over-libfabric.html