3.2) User Environment And Modules

HPC systems are necessarily complex systems and typically, it is necessary to provide or make available a large and varied number of software packages, often with multiple versions of the same software. It can be quite challenging setting up the user environment so that the required executables and/or libraries are available, particularly when different versions of the software use identical names.

Environment modules, http://modules.sourceforge.net/, provide a tool to allow users to easily control their environment and is often found on HPC clusters. Modules provide a simple interface to enable users to switch between applications and different versions of software packages, by modifying various environment variables, such as $PATH and $LD_LIBRARY_PATH.