SalvusCompute requires MPI. Our distributions come with the required MPI
binaries and shared libraries and we recommend to use these on small single
ssh site types should use the
MPI offered by the Mondaic Downloader. SalvusFlow is aware of the folder
structure the Downloader creates and no further configuration is necessary!
Large HPC clusters on the other hand tend to have their own custom MPI distributions. Our packages will dynamically link in any MPI implementation following the MPI ABI Compatibility Initiative, of which most MPI vendors are a part of.
The only widely used MPI implementation that cannot be used with Salvus is OpenMPI. OpenMPI is not ABI compatible with Salvus. Most clusters should offer an alternative.
For this to work, two manual steps might be required:
modules_to_load = ["xxx-mpich-abi"]
$LD_LIBRARY_PATH. If it does not do that, manually set it, again in the
[[sites.some_site.environment_variable]] name = "LD_LIBRARY_PATH" value = "/path/to/some/lib/dir"
The value/path has to be the library folder containing the
libmpi.so shared libraries.
Most clusters offer Intel's MPI distribution, and this generally works well with Salvus.