Introduction

As described in Run-Time Environment (page 24), SLURM and LSF-HPC cooperate to run and manage jobs on the HP XC system, combining LSF-HPC's powerful and flexible scheduling functionality with SLURM's scalable parallel job-launching capabilities.

SLURM is the low-level resource manager and job launcher, and performs core allocation for jobs. LSF-HPC gathers information about the cluster from SLURM. When a job is ready to be launched, LSF-HPC creates a SLURM node allocation and dispatches the job to that allocation.

Although you can launch jobs directly using SLURM, HP recommends that you use LSF-HPC to take advantage of its scheduling and job management capabilities. You can add SLURM options to the LSF-HPC job launch command line to further define job launch requirements. Use the HP-MPI mpirun command and its options within LSF-HPC to launch jobs that require MPI's high-performance message-passing capabilities.

When the HP XC system is installed, a SLURM partition of nodes is created to contain LSF-HPC jobs. This partition is called the lsf partition.

When a job is submitted to LSF-HPC, the LSF-HPC scheduler prioritizes the job and waits until the required resources (compute nodes from the lsf partition) are available.

When the requested resources are available for the job, LSF-HPC creates a SLURM allocation of nodes on behalf of the user, sets the SLURM JobID for the allocation, and dispatches the job with the LSF-HPC JOB_STARTER script to the first allocated node.

A detailed explanation of how SLURM and LSF-HPC interact to launch and manage jobs is provided in How LSF-HPC and SLURM Launch and Manage a Job (page 73).

Getting Information About Queues

The LSF bqueues command lists the configured job queues in LSF-HPC. By default, bqueues returns the following information about all queues:

•Queue name•Queue priority•Queue status•Job slot statistics•Job state statisticsTo get information about queues, enter the bqueues as follows:$ bqueues

For more information about using this command and a sample of its output, see Examining LSF-HPC System Queues (page 76)

Getting Information About Resources

The LSF bhosts, lshosts, and lsload commands are quick ways to get information about system resources. LSF-HPC daemons run on only one node in the HP XC system, so the bhosts and lshosts commands will list one host — which represents all the resources of the HP XC system. The total number of cores for that host should be equal to the total number of cores assigned to the SLURM lsf partition.

•The LSF bhosts command provides a summary of the jobs on the system and information about the current state of LSF-HPC.

$ bhosts

For more information about using this command and a sample of its output, see Getting the Status of LSF-HPC (page 75)

•The LSF lshosts command displays machine-specific information for the LSF execution host node.

$ lshosts

For more information about using this command and a sample of its output, see Getting Information About LSF Execution Host Node (page 75) .

•The LSF lsload command displays load information for the LSF execution host node.

28 Using the System