# Batch Queue nc_hpcff

Queue for out-of-contingent low-priority HPC-FF jobs
Applies to HPC-FF users only

Since the establishment of HPC-FF in 2009 the reliability and availability of the system has constantly improved. As desired, the system is heavily used by the fusion community most of the time. However, sometimes the utilization declines, particularly during weekends and holiday times. In order to keep the load at a high level even during such off-peak hours, JSC and the HPC-FF board have decided to define a batch queue for HPC-FF users: nc_hpcff.

All HPC-FF users are encouraged to use this queue in addition to the normal submission process, to allow jobs to run during non-prime time and without affecting their assigned CPU quota.

Please note that the general scheduling procedure is not affected by nc_hpcff, so that there is no disadvantage. If the user prefers not to use this queue, everything remains the same.

The exact specifications of nc_hpcff are:

• Jobs running in nc_hpcff will not be accounted, i.e. the user's cpu quota stays unaltered.
• CPU time used in this queue will be declared but has no impact on the user's regular cpu quota.
• Jobs have the same low scheduling priority as those running with an exhausted CPU quota. This means, jobs will be started only when no other suitable jobs are found. Especially large jobs could therefore see a longer turn-around time.
• Jobs in this queue are treated like jobs running with an exhausted CPU quota. This means, the same CPU limit (currently 12 hours) is in effect.
• JSC reserves the right to enable and suspend this queue depending on the usage needs of the system - especially, if unintended effects concerning the scheduling of normal jobs are noticed, the queue might be suspended.

This queue will be enabled:

Mondays to Thursdays: 17:00-22:00 h and
Fridays 17:00 h to Sundays 22:00 h

Please note: As before, the granted computation time will be accounted on a monthly basis. This implies that regular monthly CPU quota that is not used by the end of the next month is forfeited and will not be reimbursed. Please consult

for detailed information. The user should be aware that this procedure will not be affected by the nc-hpcff queue, i.e. even an extended use of nc_hpcff does not protect against the loss of unused CPU quota.

To submit jobs into the queue nc_hpcff, please insert the following statement in your job script:

#MSUB -q nc_hpcff