Configuration to enable preemptive scheduling

The preemptive scheduling feature is enabled by defining at least one queue as preemptive or preemptable, using the PREEMPTION parameter in the lsb.queues file. Preemption does not actually occur until at least one queue is assigned a higher relative priority than another queue, using the PRIORITY parameter, which is also set in the lsb.queues file.

Both PREEMPTION and PRIORITY are used to determine which queues can preempt other queues, either by establishing relative priority of queues or by specifically defining preemptive properties for a queue.

Configuration file

Parameter and syntax

Default behavior

lsb.queues

PREEMPTION=PREEMPTIVE

  • Enables preemptive scheduling

  • Jobs in this queue can preempt jobs in any queue of lower priority, even if the lower-priority queue is not specified as preemptable

PREEMPTION=PREEMPTABLE

  • Enables preemptive scheduling

  • Jobs in this queue can be preempted by jobs from any queue of higher priority, even if the higher-priority queue is not specified as preemptive

PRIORITY=integer

  • Sets the priority for this queue relative to all other queues

  • The larger the number, the higher the priority—a queue with PRIORITY=99 has a higher priority than a queue with PRIORITY=1
Parent topic: Preemptive Scheduling