Administering Platform LSF - SAS

Chapter 14
Fairshare Scheduling
Equal Share
Configuring
Equal share balances resource usage equally between users. This is also called
round-robin scheduling, because if users submit identical jobs, LSF runs one
job from each user in turn.
If 2 users compete for resources, they have equal importance.
To configure equal share, use the keyword default to define an equal share
for every user.
Example
Begin HostPartition
HPART_NAME = equal_share_partition
HOSTS = all
USER_SHARES = [default, 1]
End HostPartition
Priority user and static priority fairshare
Priority user fairshare
Configuring
There are two ways to configure fairshare so that a more important user’s job
always overrides the job of a less important user, regardless of resource use.
◆ Static Priority Fairshare
Dynamic priority is no longer dynamic, because resource use is ignored.
The user with the most shares always goes first.
This is useful to configure multiple users in a descending order of priority.
◆ Priority User Fairshare
Dynamic priority is calculated as usual, but more important and less
important users are assigned a drastically different number of shares, so
that resource use has virtually no effect on the dynamic priority: the user
with the overwhelming majority of shares always goes first. However, if
two users have a similar or equal number of shares, their resource use still
determines which of them goes first.
This is useful for isolating a group of high-priority or low-priority users,
while allowing other fairshare policies to operate as usual most of the time.
Priority user fairshare gives priority to important users, so their jobs override
the jobs of other users. You can still use fairshare policies to balance resources
among each group of users.
If 2 users compete for resources, and one of them is a priority user, the priority
user’s job always runs first.
To configure priority users, assign the overwhelming majority of shares to the
most important users.
Administering Platform LSF 237