I could be wrong, but there isn’t anything in the SLURM scripts you posted that says how many nodes should be used. So SLURM is free to decide where to put the six CPUs. Perhaps there weren’t six free cores on one node at job submission time, so it used two nodes in order to get six cores. If you put this in the SLURM script:
#SBATCH -N 1
That ought to tell SLURM you really insist on having just one node.
Incidentally, I don’t bother to set CUDA_VISIBLE_DEVICES. SLURM will make it look like there are only as many devices as you requested, and then CryoSPARC will use those.
Best,
Matthew Cahn
Dept. of Molecular Biology
Princeton University