Slurm Example Jobscripts

Multi-node MPI job

In this example all modules are purged and then reloaded. This is not necessary, but since your current environment gets copied to the job, this makes sure that the batch job will still behave in the same way even if you are working with different local modules interactively on the login node you are submitting from.

#!/bin/bash

#SBATCH --job-name=vasp_6.4.3_2node
#SBATCH --nodes=2
#SBATCH --ntasks-per-node=40
#SBATCH --cpus-per-task=1
#SBATCH --time=4:00:00

# Purging and reloading all modules to be sure of the job's enviroment
module purge
module load ucl-stack/2025-05
module load mpi/intel-oneapi-mpi/2021.14.0/intel-oneapi-2024.2.1
module load intel-oneapi-mkl/2023.2.0-intel-oneapi-mpi/intel-oneapi-2024.2.1
module load hdf5/1.14.3-intel-oneapi-mpi/oneapi-2024.2.1
module load vasp/6.4.3-intel-oneapi-mpi/oneapi-2024.2.1

srun vasp_std

Array job

A job array is a group of jobs with the same executable and resource requirements, but different input files. A job array can be submitted, controlled, and monitored as a single unit. Each job submitted from a job array shares the same job ID as the job array and has its own $SLURM_ARRAY_TASK_ID.

At present, the maximum allowed size of a job array is 1000 tasks.

#!/bin/bash
#SBATCH --ntasks=1
#SBATCH --cpus-per-task=1
#SBATCH --job-name=myArray
#SBATCH --time=00:30:00
#SBATCH --array=1-10

# Each task processes a different csv data file
myprogram dataset${SLURM_ARRAY_TASK_ID}.csv

The array is created by Slurm directive --array=1-10 by including elements numbered [1-10] to represent our 10 input files.

When the array job is submitted, Slurm will create 10 jobs under the single job ID. The job array script is submitted in the usual way:

sbatch myarrayjob

Enabling Hyperthreads

Hyperthreading lets you use two virtual cores instead of one physical core - some programs can take advantage of this.

On clusters with hyperthreading enabled (Kathleen, Young, Michael), you can request it with:

#SBATCH --hint=multithread

This tells Slurm to schedule two threads per physical core.

By default we have set --hint=nomultithread so hyperthreads will not be used unless requested.