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====== Use /tmp for I/O intensive single node jobs ======

Jobs that do a lot of I/O operations on a shared cluster filesystem like ''/scratch'' can severely slow down the whole system. If your job does not use multiple nodes and is not reading and writing very large files, it might be a good idea to move input and output files to the ''/tmp'' folder on the compute node itself.

''/tmp'' is a RAM based filesystem, meaning that anything you store there is actually stored in memory. So space is quite limited. Currently all jobs on a node can use at most 20% of the total system memory for space in ''/tmp''. If you need more space, you should consider using ''/dev/shm'', where you can use up to 50% of the total system memory per job.


<note important>
Usable space below /tmp and /dev/shm counts towards your job's memory usage and thus is limited by the ''--mem'' option
</note>