PLEIADES

User documentation for the PLEIADES cluster at the University of Wuppertal

Best Practise

Note:

Your files on BeeGFS are not backed up! Make sure to regularly store important results and data on another device. In case of a catastrophic failure or event, we won’t be able to restore the data.

BeeGFS and /tmp

Many and frequent accesses to files on /beegfs can produce significant load on the metadata servers. In consequence, the responsiveness of the shared filesystem goes bad for all users. There are a couple of things you should avoid when working on /beegfs, because of this:

If your job is aborted for any reason, you probably left files in /tmp that you want to rescue or remove. Right now, the best approach is to book an interactive shell on the node and resolve it manually, via:

srun -p short -w wn21053 -n1 -t 60 --pty /bin/bash

Slurm

Every job submission in Slurm introduces some overhead to the batch system. If you have many short jobs of the same kind, e.g. 2000 x 30 minutes, you should combine your workload in fewer submission scripts or consider using Slurms job arrays. This way you bundle all of these jobs in a single job submission, but still can treat the items individually as job steps.

Please try to estimate a maximum execution time and set your job time limits accordingly.

Moving Data

The login nodes, especially fugg1 and 2, are mostly intended for job submissions. If you expect to move larger amounts of data, e.g. to a local computer, consider submitting a job that moves the data from a worker node to your system. This way, you can shift the workload away from login nodes.