LSF Version 7.3 - Administering Platform LSF

Administering Platform LSF 35
How the System Works
300 and less than or equal to one-half the value of MAX_SBD_CONNS defined in
lsb.params. LSB_MAX_JOB_DISPATCH_PER_SESSION defines the maximum
number of jobs that
mbatchd can dispatch during one job scheduling session. You
must restart
mbatchd and sbatchd when you change the value of this parameter for
the change to take effect.
Dispatch order
Jobs are not necessarily dispatched in order of submission.
Each queue has a priority number set by an LSF Administrator when the queue is
defined. LSF tries to start jobs from the highest priority queue first.
By default, LSF considers jobs for dispatch in the following order:
◆ For each queue, from highest to lowest priority. If multiple queues have the
same priority, LSF schedules all the jobs from these queues in first-come,
first-served order.
◆ For each job in the queue, according to FCFS order
◆ If any host is eligible to run this job, start the job on the best eligible host, and
mark that host ineligible to start any other job until JOB_ACCEPT_INTERVAL
has passed
Jobs can be dispatched out of turn if pre-execution conditions are not met, specific
hosts or resources are busy or unavailable, or a user has reached the user job slot
limit.
Viewing job order in queue
Use bjobs to see the order in which jobs in a queue will actually be dispatched for
the FCFS policy.
Changing job order in queue (btop and bbot)
Use the btop and bbot commands to change the job order in the queue.
See Changing Job Order Within Queues on page 120 for more information.