This lesson introduces the topic of the job scheduler, sometimes referred to as the workload manager, as its role on an HPC system is to manage the fair execution of jobs on the system. 

Learning Objectives:

• Describe briefly what a job scheduler does.
• Recap the fundamentals of Slurm job submission and monitoring.
• Use Slurm and SAFE to determine the submission parameters to use to submit a job.
• Summarise the main ways researchers may request time on a DiRAC facility.

This lesson builds on the introduction and develops your knowledge about specifying resources, how to manage your job, creating more complex job submitions, and backfilling, to ensure quick excection.

Learning Objectives:

• Specify a job’s resource requirements in a Slurm batch script.
• Describe the main states a job passes through from start to completion.
• Cancel multiple jobs using a single command.
• Describe how backfilling works and why it’s useful.
• Obtain greater detail regarding the status of a job and its use of resources.

This lesson focuses on the typical module system that is found on most HPC systems. The module system enables you to configure your environment so you can access the correct version of software you require.

At the end of this lesson you will understand why we use the module system, how it changes your environment, and how to use it with your scripts to ensure your submitted job has the correct environment when running.

Learning Objectives:

• Load and use a software package
• Explain how the shell environment changes when the module mechanism loads or unloads packages
• Use modules in a job script.

Not all research jobs are the same, you may have a large or a small job, or a job that is built on many parts that may depend on each other, or even a hybrid submission of MPI and OpenMP.

In this lesson you will learn about these different jobs and how to achieve them on a HPC system like DiRAC.

Learning Objectives:

• Use a popular compiler to compile a C program before testing and submitting it
• Use a compute node for a job exclusively
• Describe how an OpenMP job parallelises its computation
• Compile and submit an OpenMP job
• Describe how an MPI job parallelises its computation
• Compile and submit an MPI job
• Highlight the key differences between OpenMP and MPI jobs
• Define and submit an array job to execute multiple tasks within a single job
• Use an interactive job to run commands remotely on a compute node.