Several MPI implementations are available on the Atos HPCF: OpenMPI (provided by AtosMellanox HPC-X (OpenMPI based), Intel MPI and Mellanox HPC-X (OpenMPI based and OpenMPI (provided by Atos).
They are not compatible amongst them, so you should only use one to build your entire software stack. Support libraries are provided for the different flavours to guarantee maximum compatibility.
| Tip |
|---|
| title | Recommended MPI implementation |
|---|
|
The recommended MPI implementation for stability and performance is hpcx-openmpi/2.9.0 |
Building your MPI programs
...
| Code Block |
|---|
| title | Example: Using GNU compilers and HPC-X OpenMPI implementation |
|---|
|
$ module load prgenv/gnu hpcx-openmpi
$ module list
Currently Loaded Modules:
1) gcc/8.35.10 2) prgenv/gnu 3) hpcx-openmpi/42.9.0.5.1 |
| Code Block |
|---|
| title | Example: Using Intel compilers and Intel MPI implementation |
|---|
|
$ module load prgenv/intel intel-mpi
$ module list
Currently Loaded Modules:
1) intel/192021.14.20 2) prgenv/intel 3) intel-mpi/192021.14.20 |
Then, you may use the usual MPI compiler wrappers to compile your programs:
| Language | OpenMPI (including HPC-X) | Intel MPI with Intel compilers | Intel MPI with GNU compilers | OpenMPI
|---|
| CC | mpicc | mpiicc | mpigcc | mpicc |
| C++ | mpicxx | mpiicpc | mpigxx | mpicxx
| FortranFortran | mpifort | mpiifort | mpif90 | mpifort |
| Tip |
|---|
When using Intel MPI it is important to use the correct compiler wrapper depending on whether you want to use Intel or GNU compilers. |
...