Platform R: Slurm Constraints

Slurm Features

For most people any software they have installed on Platform R will run on all nodes in the Slurm cluster. This includes most R and Python packages. However, some packages take advantage of more advanced features of particular CPUs to improve performance. If some of your jobs are failing with an "illegal instruction" error, in particular, it is likely that the software needs Slurm to restrict which nodes it runs on. In that situation you can specify a specific CPU or advanced CPU feature in your Slurm batch file. These are handled with constraints:

##SBATCH --constraint="<feature-name>"

You can create complex constraints by using an ampersand character (&) for "and" and a pipe character for "or," such as --constraint="intel&avx2" or --constraint="avx2|sse42"

If your jobs would benefit from a particular feature but it is not a requirement, you can use the --prefer option. Your jobs will run preferentially on nodes with the matching features, but might still run on other nodes.

The sinfo command can give a list of the features available across the cluster. The format directive for that is %b. For example, if you run sinfo -o "%9P %5a %5D %20N %b" you will see that both Intel and AMD CPUs are available in the Platform R cluster.

Available Constraints

The sinfo command will show the available constraints under the "Active Features" column.

Related Documentation

• Platform R: Getting Started