Creating Sun HPC-Specific Queues

Because HPC jobs distribute multiple processes across multiple nodes, their batch queue requirements are different from those of serial jobs. For this reason, you should specifically configure one or more batch queues for running Sun HPC jobs. This involves editing the queue configuration file, lsb.queues. Sections "Specify PAM as Job Starter" and "Enable Interactive Batch Mode" discuss the queue parameters of primary interest, JOB_STARTER and INTERACTIVE.

Specify PAM as Job Starter

The JOB_STARTER parameter allows an LSF batch queue to pass job launching control over to a special job-starting procedure rather than launching the job itself. For Sun HPC applications, this job launching role is given to the Parallel Application Manager (PAM), which is a utility for starting and managing MPI jobs.

PAM should be specified as the job starter on all queues that will be used by Sun HPC jobs. To do this, simply edit the JOB_STARTER line in lsb.queues to read as follows:

JOB_STARTER=pam

When a Sun HPC job is submitted to a PAM-configured queue, the queue will start PAM running. PAM, in turn, will launch the Sun HPC job on the cluster.

Enable Interactive Batch Mode

LSF supports the concept of interactive batch job execution. When a job is submitted in interactive batch mode, it receives the same batch scheduling and host selection services as noninteractive batch jobs, but the terminal from which the job was submitted remains attached to the job as if it were launched interactively.

Interactive batch mode is the only interactive mode Sun HPC ClusterTools 3.0 software supports.

By default, both batch mode and interactive batch mode are available. To select interactive batch mode, include the -I option on the bsub command line. Without this option, bsub invokes conventional batch mode.

The INTERACTIVE parameter in the lsb.queues file allows you restrict a queue to accept only interactive batch jobs or exclude all interactive batch jobs. Use it to restrict Sun HPC-dedicated queues to interactive batch jobs. Otherwise, noninteractive jobs could be added to the queue, which could make the queue less efficient for handling the interactive batch jobs. To impose this restriction, add the following line to the appropriate queue descriptor in the lsb.queues file:

INTERACTIVE=ONLY

All jobs submitted to a queue configured in this way must include the -I option on the bsub command line.

Separate queues can be configured for batch-mode-only jobs as well.

Because interactive batch jobs need fast response times, there are other steps you should take to minimize job launch latencies normally associated with batch queue behavior. These are described in the next section.