Platform LSF Administration Guide Version 6.2

Chapter 16
Fairshare Scheduling
Administering Platform LSF
307
Users Affected by Multiple Fairshare Policies
If you belong to multiple user groups, which are controlled by different fairshare
policies, each group probably has a different dynamic share priority at any given time.
By default, if any one of these groups becomes the highest priority user, you could be
the highest priority user in that group, and LSF would attempt to place your job.
To restrict the number of fairshare policies that will affect your job, submit your job and
specify a single user group that your job will belong to, for the purposes of fairshare
scheduling. LSF will not attempt to dispatch this job unless the group you specified is
the highest priority user. If you become the highest priority user because of some other
share assignment, another one of your jobs might be dispatched, but not this one.
Submitting a job and specifying a user group
To associate a job with a user group for the purposes of fairshare scheduling, use
bsub -G and specify a group that you belong to. If you use hierarchical fairshare, you
must specify a group that does not contain any subgroups.
Example
User1
shares resources with groupA and groupB. User1 is also a member of
groupA, but not any other groups.
User1 submits a job:
bsub sleep 100
By default, the job could be considered for dispatch if either User1 or GroupA has
highest dynamic share priority.
User1 submits a job and associates the job with GroupA:
bsub -G groupA sleep 100
If User1 is the highest priority user, this job will not be considered.
◆ User1 can only associate the job with a group that he is a member of.
◆ User1 cannot associate the job with his individual user account, because bsub -
G
only accepts group names.
Example with
hierarchical
fairshare
In the share tree, User1 shares resources with GroupA at the top level. GroupA has 2
subgroups, B and C.
GroupC has 1 subgroup, GroupD. User1 also belongs to GroupB
and
GroupC.
User1 submits a job:
% bsub sleep 100
By default, the job could be considered for dispatch if either User1, GroupB, or
GroupC has highest dynamic share priority.
User1 submits a job and associates the job with GroupB:
% bsub -G groupB sleep 100
If User1 or GroupC is the highest priority user, this job will not be considered.
◆ User1 cannot associate the job with GroupC, because GroupC includes a
subgroup.
◆ User1 cannot associate the job with his individual user account, because bsub -
G
only accepts group names.