A shared software stack

  • A shared stack is one supported copy of a program, selected with a module.
  • CVMFS shows /cvmfs/software.eessi.io and fetches a file when you first use it.
  • EasyBuild, and how a module file is produced, is the book at https://hpceb.rgoswami.me/.
  • The init script prints a CPU target. The example x86_64/intel/sapphirerapids can differ.
  • module purge before you switch stacks. Do not load two stacks in one shell.

Finding and loading a module

  • module avail is the current level. module spider searches the rest.
  • module load selects. module unload removes one. module purge clears the shell.
  • EESSI 2025.06 default Python is Python/3.13.5-GCCcore-14.3.0, and python3 --version prints Python 3.13.5.
  • EESSI 2023.06 has Python/3.11.5-GCCcore-13.2.0. Purge before you load it.
  • QCG-PilotJob is a site module. Spider does not find it in EESSI.

The EESSI client container

  • The EESSI client is an Apptainer container that mounts /cvmfs/software.eessi.io.
  • The init script is source /cvmfs/software.eessi.io/versions/2025.06/init/lmod/bash.
  • $EESSI_VERSION prints 2025.06. $EESSI_CVMFS_REPO prints /cvmfs/software.eessi.io.
  • The CPU line x86_64/intel/sapphirerapids is an example and may differ.
  • The container has no sbatch. python3 --version still prints Python 3.13.5.