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The "Size (per core)" column is used to highlight the fact that the HPC cluster is a shared resource. The values are based on capacity (/home = 512TiB), not free space (/home = 92TiB on 22-Feb-2021). Should a filesystem fill up, all jobs using that filesystem will be impacted (killing jobs is probably the best option). As a result, if you are running an I/O intensive single core job that requires 9GiB of storage, /fast is the best/safest option.
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