LSF Version 7.3 - Platform LSF Configuration Reference

When … The behavior is …
A queue is defined as preemptable, and
one or more queues are specified that can
preempt it
•
Jobs from this queue can be preempted only by jobs from the
specified queues
A queue is defined as preemptive, but no
specific queues are listed that it can
preempt
•
Jobs from this queue preempt jobs from all queues with a lower
value for priority
•
Jobs are preempted from the least-loaded host
A queue is defined as preemptive, and one
or more specific queues are listed that it can
preempt, but no queue preference is
specified
•
Jobs from this queue preempt jobs from any queue in the specified
list
•
Jobs are preempted on the least-loaded host first
A queue is defined as preemptive, and one
or more queues have a preference number
specified, indicating a preferred order of
preemption
•
Queues with a preference number are preferred for preemption
over queues without a preference number
•
Queues with a higher preference number are preferred for
preemption over queues with a lower preference number
•
For queues that have the same preference number, the queue with
lowest priority is preferred for preemption over queues with higher
priority
•
For queues without a preference number, the queue with lower
priority is preferred for preemption over the queue with higher
priority
A queue is defined as preemptive, or a
queue is defined as preemptable, and
preemption of jobs with the shortest run
time is configured
•
A queue from which to preempt a job is determined based on other
parameters as shown above
•
The job that has been running for the shortest period of time is
preempted
A queue is defined as preemptive, or a
queue is defined as preemptable, and
preemption of jobs that will finish within a
certain time period is prevented
•
A queue from which to preempt a job is determined based on other
parameters as shown above
•
A job that has a run limit or a run time specified and that will not
finish within the specified time period is preempted
A queue is defined as preemptive, or a
queue is defined as preemptable, and
preemption of jobs with the specified run
time is prevented
•
A queue from which to preempt a job is determined based on other
parameters as shown above
•
The job that has been running for less than the specified period of
time is preempted
Case study: Three queues with varying priority
Consider the case where three queues are defined as follows:
Queue A has the highest relative priority, with a value of 99
Queue B is both preemptive and preemptable, and has a relative priority of 10
Queue C has the lowest relative priority, with the default value of 1
The queues can preempt as follows:
•
A can preempt B because B is preemptable and B has a lower priority than A
•
B can preempt C because B is preemptive and C has a lower priority than B
Feature: Preemptive scheduling
Platform LSF Configuration Reference 49