HP XC System Software Administration Guide Version 3.0

Launching Jobs with LSF-HPC
You may not submit LSF-HPC jobs as superuser (root). You may find it convenient to run jobs as the local
lsfadmin user. An example would be a job to test a new queue configuration.
The LSF-HPC daemons run on one node only: the LSF execution host. Therefore, they can dispatch jobs only
on that node. The JOB_STARTER script, described in “Job Starter Scripts” (page 119), ensures that user jobs
execute on their reserved nodes, and that these jobs do not contend for the LSF execution host.
Consider an HP XC system in which node n120 is the LSF execution host, and nodes n1 through n99 are
compute nodes. The following series of examples shows jobs launched without the JOB_STARTER script
with varied results.
Example 13-3. illustrates the launching of a job in its most basic form.
Example 13-3. Basic Job Launch Without the JOB_STARTER Script Configured Basic Job Launch Without
the JOB_STARTER Script Configured
$ bsub -I hostname
Job <20> is submitted to default queue <normal>.
<<Waiting for dispatch...>>
<<starting on lsfhost.localdomain>>
n120
Example 13-4. is a similar example, but 20 processors are reserved.
Example 13-4. Launching Another Job Without the JOB_STARTER Script Configured Launching Another
Job Without the JOB_STARTER Script Configured
$ bsub -I -n20 hostname
Job <21> is submitted to default queue <normal>.
<<Waiting for dispatch...>>
<<starting on lsfhost.localdomain>>
n120
In both of the previous examples, processors were reserved but not used. To ensure that a job is launched
properly on the reserved nodes without the JOB_STARTER script configured, the user must preface each
command with either the srun command or the mpirun -srun command, as shown in Example 13-5.
and Example 13-6..
Example 13-5. Launching a Job Successfully Without the JOB_STARTER Script Using srun Launching a Job
Successfully Without the JOB_STARTER Script Using srun
$ bsub -I srun hostname
Job <22> is submitted to default queue <normal>.
<<Waiting for dispatch...>>
<<starting on lsfhost.localdomain>>
n99
Example 13-6. Launching a Job Successfully Without the JOB_STARTER Script Using mpirun Launching a
Job Successfully Without the JOB_STARTER Script Using mpirun
$ bsub -I -n4 mpirun -srun hostmpi
Job <23> is submitted to default queue <normal>.
<<Waiting for dispatch...>>
<<starting on lsfhost.localdomain>>
task 0 running on n1
task 1 running on n1
task 2 running on n2
task 3 running on n2
Example 13-7. illustrates launching the same job as in Example 13-3., but with the JOB_STARTER script
configured.
Administering LSF-HPC 125