Managing software on ARC

Overview

In addition to basic software distributed with most Linux systems, additional application packages and libraries have been installed for use on ARC under /global/software. Also see the module avail command below for a list of some of the installed software packages. Write to support@hpc.ucalgary.ca if you need additional software installed.

Environment modules

To facilitate the use of some of the software on the ARC cluster one can load a corresponding environmental module file, which may add an installation directory to the PATH variable used to locate the executable files, or help the software find libraries upon which it depends. An overview of modules on WestGrid is largely applicable to ARC.

To list the software for which an environment module file has been created, use the command:

$ module avail

Then, to set up your environment to use a particular package, use the module load command. For example, to load a module for Python use:

$ module load python/anaconda-3.6-5.1.0

If you need to undo the changes made by loading the module, you can use the module unload command:

$ module unload python/anaconda-3.6-5.1.0

To see currently loaded modules, type:

$ module list

Unlike some clusters, there are no modules loaded by default. So, for example, to use Intel compilers, or to use Open MPI parallel programming, you must load an appropriate module.

Installing Software in User's Home Directory

ARC is a multi-user system and on such a system users cannot do anything that affects other users. Using the sudo command implies that you what to do something that affect other users, this is why you cannot use sudo.

Using a package manager (apt, yum, etc.) does require changing common system directories, which would affect all users on the system. At the same time, the package manager would install software onto the login node only. Login node is not supposed to run your computations, the compute nodes are, but the package manager that you run on the login node cannot install software to the compute nodes, which are different computers.

Thus, software that you want to use on ARC must be installed onto a shared file system that is accessible by all the nodes in the cluster. If we (analysts) install software centrally, we install it into /global/software shared directory, if a user wants to install a software package and manage it on his/her own, than it has to be installed into the user's home directory, that is /home/$HOME. In such cases package managers cannot be used and the software often has to be compiled on ARC and the desired installation location has to be specified during the compilation process. If there is a dependency, library or another software package, that has to be present in the system, then the dependency has to be installed the same way prior to the compilation.