LSF Version 7.3 - Running Jobs With Platform LSF

Submitting a Job and Indicating Host Preference
When several hosts can satisfy the resource requirements of a job, the hosts are ordered
by load. However, in certain situations it may be desirable to override this behavior to
give preference to specific hosts, even if they are more heavily loaded.
For example, you may have licensed software which runs on different groups of hosts,
but you prefer it to run on a particular host group because the jobs will finish faster,
thereby freeing the software license to be used by other jobs.
Another situation arises in clusters consisting of dedicated batch servers and desktop
machines which can also run jobs when no user is logged in. You may prefer to run on
the batch servers and only use the desktop machines if no server is available.
To see a list of available hosts, use the
bhosts command.
◆ “Submitting a job with host preference” on page 36
◆ “Submitting a job with different levels of host preference” on page 37
◆ “Submitting a job with resource requirements” on page 37
Submitting a job with host preference
The bsub -m option allows you to indicate preference by using + with an optional
preference level after the host name. The keyword
others can be used to refer to all
the hosts that are not explicitly listed. You must specify
others with at least one host
name or host group name.
For example:
bsub -m "hostD+ others" -R "solaris && mem> 10" myjob
In this example, LSF selects all solaris hosts that have more than 10 MB of memory
available. If
hostD meets this criteria, it will be picked over any other host which
otherwise meets the same criteria. If
hostD does not meet the criteria, the least loaded
host among the others will be selected. All the other hosts are considered as a group and
are ordered by load.
A queue can also define host preferences for jobs. Host preferences specified by
bsub -m override the queue specification.
In the queue definition in
lsb.queues, use the HOSTS parameter to list the hosts or
host groups to which the queue can dispatch jobs.
Use the not operator (
~) to exclude hosts or host groups from the list of hosts to which
the queue can dispatch jobs. This is useful if you have a large cluster, but only want to
exclude a few hosts from the queue definition.
See the Platform LSF Reference for information about the
lsb.queues file.