Slurm

HPC clusters run job schedulers to distribute and manage computational resources. Generally, schedulers:

• Manage and enforce resource constraints, such as execution time, number of CPU cores, and amount of RAM a job may use;
• Provide tools for efficient communication between nodes during parallel workflows;
• Fairly coordinate the order and priority of job execution between users;
• Monitor the status and utilization of nodes.

HPCCF clusters use Slurm for job scheduling. A central controller runs on one of the file servers, which users submit jobs to from the access node using the srun and sbatch commands. The controller then determines a priority for the job based on the resources requested and schedules it on the queue. Priority calculation can be complex, but the overall goal of the scheduler is to optimize a tradeoff between throughput on the cluster as a whole and turnaround time on jobs.

The Commands section describes how to manage jobs and check cluster status using standard Slurm commands. The Resources section describes how to request computing resources for jobs. The Job Scripts section includes examples of job scripts to be used with sbatch.