HPC applications typically have to avoid swapping, since they are likely to be limited by the resource manager and compute nodes typically have minimal or no sw

HPC applications typically have to avoid swapping, since they are likely to be limited by the resource manager and compute nodes typically have minimal or no swap space anyway. (The reason you might want a big swap area is to be able to suspend jobs in favour of higher-priority ones.) It's often a significant performance issue if you even need to go off the NUMA node to memory.