Threaded Jobs on the Cluster

It is possible to submit jobs to the cluster that require more than one core to execute.

To make a job reserve more than one slot use the following directive in the script:

   #$ -pe threaded ## -R y

Where ## is the number of slots your job needs. It is important to include the "-R y" as it will ensure your job starts reserving slots. Without this, it may not be executed for a very long time.

It is possible to request a range of slots and then reference the number allocated during execution. Simply provide a range for the number of slots in the parallel environment (pe) directive. The number of slots is then available in the $pe_slots environmental variable.

   #$ pe threaded 4-8 -R y
   
   ...
   /run/some/threaded command --threaded --cores=$pe_slots

Note that even with reserved slots, multi-slot jobs often take a long time to leave the queue. It is worth your while to try breaking your job up into a number of smaller, serial jobs if possible.