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2 submitting a non-mpi parallel job, Example 2-2: submitting a non-mpi parallel job – HP XC System 2.x Software User Manual

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2.3.5.2 Submitting a Non-MPI Parallel Job

Submitting non-MPI parallel jobs is discussed in detail in Section 7.4.4. The LSF

bsub

command format to submit a simple non-MPI parallel job is:

bsub -n num-procs [bsub-options] srun [srun-options] executable

[executable-options]

The

bsub

command submits the job to LSF-HPC.

The

-n

num-procs parameter specifies the number of processors requested for the job. This

parameter is required for parallel jobs.

The inclusion of the SLURM

srun

command is required in the LSF-HPC command line to

distribute the tasks on the allocated compute nodes in the LSF partition.

The

executable

parameter is the name of an executable file or command.

Consider an HP XC configuration where

lsfhost.localdomain

is the LSF-HPC

execution host and nodes

n[1-10]

are compute nodes in the SLURM

lsf

partition. All

nodes contain two processors, providing 20 processors for use by LSF-HPC jobs. The following
example shows one way to submit a non-MPI parallel job on this system:

Example 2-2: Submitting a Non-MPI Parallel Job

$ bsub -n4 -I srun hostname

Job <21> is submitted to default queue

<>

<>

n1

n1

n2

n2

In the above example, the job output shows that the job “

srun hostname

” was launched

from the LSF execution host

lsfhost.localdomain

, and that it ran on four processors

from the allotted nodes

n1

and

n2

.

Refer to Section 7.4.4 for an explanation of the options used in this command, and for full
information about submitting a parallel job.

Using SLURM Options with the LSF External Scheduler

An important option that can be included in submitting parallel jobs is LSF-HPC’s external
scheduler option. The LSF-HPC external SLURM scheduler provides additional capabilities at
the job and queue levels by allowing the inclusion of several SLURM options in the LSF-HPC
command line. For example, it can be used to submit a job to run one task per node, or to
submit a job to run on only specified nodes.

The format for this option is:

-ext "SLURM[slurm-arguments]"

The

slurm-arguments

can consist of one or more

srun

allocation options (in long format).

Refer to Section 7.4.2 for additional information about using the LSF-HPC external scheduler.
The Platform Computing LSF documentation provide more information on general external
scheduler support. Also see the

lsf_diff

(1)

manpage for information on the specific

srun

options available in the external SLURM scheduler.

The following example uses the external SLURM scheduler to submit one task per node (on
SMP nodes):

Using the System

2-9