LSF Version 7.3 - Administering Platform LSF

Hierarchical User-based Fairshare
306 Administering Platform LSF
Controlling job dispatch order in cross-queue fairshare
DISPATCH_ORDER
parameter
(lsb.queues)
Use DISPATCH_ORDER=QUEUE in the master queue to define an ordered
cross-queue fairshare set. DISPATCH_ORDER indicates that jobs are dispatched
according to the order of queue priorities, not user fairshare priority.
Priority range in
cross-queue
fairshare
By default, the range of priority defined for queues in cross-queue fairshare cannot
be used with any other queues. The priority of queues that are not part of the
cross-queue fairshare cannot fall between the priority range of cross-queue
fairshare queues.
For example, you have 4 queues:
queue1, queue2, queue3, and queue4. You
configure cross-queue fairshare for
queue1, queue2, and queue3, and assign
priorities of 30, 40, 50 respectively. The priority of
queue4 (which is not part of the
cross-queue fairshare) cannot fall between 30 and 50, but it can be any number up
to 29 or higher than 50. It does not matter if
queue4 is a fairshare queue or FCFS
queue.
If DISPATCH_ORDER=QUEUE is set in the master queue, queues that are not part
of the ordered cross-queue fairshare can have any priority. Their priority can fall
within the priority range of cross-queue fairshare queues and they can be inserted
between two queues using the same fairshare tree. In the example above,
queue4
can have any priority, including a priority falling between the priority range of the
cross-queue fairshare queues (30-50).
Jobs from equal
priority queues
◆ If two or more non-fairshare queues have the same priority, their jobs are
dispatched first-come, first-served based on submission time or job ID as if
they come from the same queue.
◆ If two or more fairshare queues have the same priority, jobs are dispatched in
the order the queues are listed in
lsb.queues.
Hierarchical User-based Fairshare
For both queue and host partitions, hierarchical user-based fairshare lets you
allocate resources to users in a hierarchical manner.
By default, when shares are assigned to a group, group members compete for
resources according to FCFS policy. If you use hierarchical fairshare, you control
the way shares that are assigned collectively are divided among group members.
If groups have subgroups, you can configure additional levels of share assignments,
resulting in a multi-level share tree that becomes part of the fairshare policy.
How hierarchical fairshare affects dynamic share priority
When you use hierarchical fairshare, the dynamic share priority formula does not
change, but LSF measures the resource consumption for all levels of the share tree.
To calculate the dynamic priority of a group, LSF uses the resource consumption of
all the jobs in the queue or host partition that belong to users in the group and all
its subgroups, recursively.