Loadleveler Classes

The main classes on Abacus4 are:

Class Properties
long tCPU unlimited
medium tCPU < 1 week
short tCPU < 12 hours

A full list of all available classes can be obtained with the command llclass.

The LoadLeveler class is specified in the control file in a line which contains the keyword class, e.g.
   # @ class = medium

CAUTION! Jobs should only be started in the class long, if they really do require more CPU time than is available in medium! If a node has to be emptied for maintenance, the class long will be closed first. Thus, in total, fewer resources are available for these jobs!

In the past, many jobs have been started unnecessarily in the class long, as can be seen in the graphic below. The jobs which consumed less than 168 hours should have been started in the class medium or even short.

job_cpu_long_2010.png