A cluster is a waiting room, a contract for software, a scheduler, and only then an accelerator. These notes stay in that order.
The login image is not a workstation. The modulefile is the stack you actually have. A job that finishes is mostly walltime, cwd, and the launcher. A GPU run starts with a device you can see, not the full application.
The four-rank cartoon is the shape of an
srun, not a screenshot from a centre.Slurm's sbatch is the usual door. The first page is login-node etiquette.