Specify a job priority (bsub -sp)

Valid values for priority specified by bsub -sp are any integers between 1 and MAX_USER_PRIORITY (configured in lsb.params, displayed by bparams -l). Job priorities that are not valid are rejected. LSF and queue administrators can specify priorities beyond MAX_USER_PRIORITY.

Job owners can change the priority of their own jobs. LSF and queue administrators can change the priority of all jobs in a queue.

Job order is the first consideration to determine job eligibility for dispatch. Jobs are still subject to all scheduling policies regardless of job priority. Jobs are scheduled based on priority and order in the queue, in the following order:

  1. Queue priority

  2. Job priority

  3. First-come first-served order in the queue

Administrators can configure user-assigned job priority with automatic job priority escalation to automatically increase the priority of jobs that have been pending for a specified period of time (JOB_PRIORITY_OVER_TIME in lsb.params). For example, JOB_PRIORITY_OVER_TIME=1/1 increases the job priority of a pending job by 1 every minute.

For job priority escalation to take effect on pending jobs in the execution cluster, JOB_PRIORITY_OVER_TIME must be defined in lsb.params in the execution cluster. MAX_USER_PRIORITY must be defined in lsb.params in the execution cluster for the job priority specified in submission cluster to be propagated to execution cluster.

Note:

The btop and bbot commands only move jobs within the queue relative to other jobs with the same priority. These commands do not change job priority.

Job priority scaling

If both clusters have different values for MAX_USER_PRIORITY, the execution cluster will scale up or down when the job is forwarded to the execution cluster.

Job priority scaling is based on the following formula:

job_priority = submission_job_priority * MAX_USER_PRIORITY_exec_cluster / MAX_USER_PRIORITY_sub_cluster

Where:

  • submission_job_priority is the job priority in the submission cluster

  • job_priority is the calculated job priority in submission cluster based on the summission job priority, the MAX_USER_PRIORITY of the execution cluster and the MAX_USER_PRIORITY of the submission cluster

The scaled job priority cannot drop below 1.

The bjobs -l command from the submission cluster displays the initial job priority and the dynamic job priority of submission cluster. It does not display dynamic job priority for execution cluster.

For example, if MAX_USER_PRIORITY in the submission cluster is 10 and MAX_USER_PRIORITY in the execution cluster is 20, a job submitted with a job priority of 4 will have a job priority of 8 in the execution cluster.