Uppsala Multidisciplinary Center for Advanced Computational Science

Login node restrictions / limits

The login nodes (e.g. milou-f, milou1, milou2, tintin1, tintin2, tintin3, etc) have various limits in place that aim to limit how much users can disturb other users by consuming too much of any shared resource.

This can sometimes confuse users. For example, we highly prioritize system stability, meaning if the system runs out of CPU, "system related" processes will have a much better chance of getting CPU than any user process. What is left will be divided between users with processes that want to run in a fair way (more processes/threads won't mean more CPU is allocated).

As normal, anything using all it can of any single any resource over any significant amount of time should be submitted as a job to our batch system SLURM.

There's also a limit on the total amount of memory that any user can consume and if you try to use to much your processes will fail - for larger tasks you should use the batch system as usual.

You can see some other limits imposed by typing "ulimit -a".