This plugin adds support for the automatic creation of job or job-step RAM disks to SLURM.

The plugin adds an option --ramdisk to sbatch/srun, which sequesters a portion of the job's (or step's) memory allocation for a temporary filesystem. The value specified can be suffixed with M for megabytes (default), or G for gigabytes.

The plugin relies on your SLURM installation using CGroups for memory constraints. It creates the temporary filesystem within the CGroup, which means any RAM disk usage is counted as memory usage from your allocation. It is thus important to increase the job memory requested alongside the --ramdisk option.

During runtime, the path is stored under the environment variable SLURM_JOB_RAMDISK. At job (or step) completion, the temporary filesystem is removed and all data within it is discarded.

The plugin can be compiled easily with gcc, and should be copied somewhere in your SLURM libs folder:

gcc -shared -fPIC -o ramdisk.so ramdisk.c
sudo mkdir -p /usr/local/lib/slurm/spank
sudo cp ramdisk.so /usr/local/lib/slurm/spank/ramdisk.so

You must also edit plugstack.conf to include the plugin:

required /usr/local/lib/slurm/spank/ramdisk.so