How to install Wi4MPI

Learning objectives

With these hands-on exercises, participants will learn:

  • how to configure their environment in preparation for Wi4MPI installation

  • how to install Wi4MPI using the Spack package manager

  • how to configure Wi4MPI in their environment to efficiently use the library

Once participants complete these exercises, they will have a working Wi4MPI environment ready to use.

Installing Wi4MPI using Spack

Wi4MPI is available through Spack and the Spack package is updated with each new version.

Setup

To install Wi4MPI, one needs to first install a compiler supporting C, C++, and Fortran, given that these compilers are needed for MPI compilation. For example:

  • Debian-like distro:

(sudo) apt install gcc-11 g++-11 gfortran-11

  • RHEL-like distro:

(sudo) yum install gcc gcc-c++ gcc-gfortran

Spack installation

Then, install and configure Spack using the compilers previously installed:

git clone https://github.com/spack/spack.git
source spack/share/spack/setup-env.sh
spack compiler find

Once Spack is configured, you can install Wi4MPI and an alternative MPI implementation:

spack install wi4mpi
spack install mpich

Wi4MPI configuration

Once Wi4MPI and the different MPI implementations are installed, Wi4MPI needs to be configured. To do so, the paths to the available MPI implementations need to be specified:

spack load wi4mpi
echo 'OPENMPI_DEFAULT_ROOT="</path/to/openmpi/root>"' >> $WI4MPI_ROOT/etc/wi4mpi.cfg
echo 'MPICH_DEFAULT_ROOT="</path/to/mpich/root>"' >> $WI4MPI_ROOT/etc/wi4mpi.cfg

The above paths need to be updated with the actual paths on your system.