The batch job queing system used on Louhi is Portable Batch System, Professional Edition (PBS Pro) which uses Application Level Placement Scheduler (ALPS) for placing and launching applications for execution on compute nodes of Louhi.

This chapter describes how to use PBS Pro, including its most important commands and their options, how to submit jobs, how to monitor, display and get information about hosts, queues and jobs, and how to manage jobs and  remove them from the queue. Batch job script examples are given.

All batch jobs must be submitted to compute nodes via the queuing mechanism of PBS Pro. Usage of job launching ALPS command aprun and some other ALPS commands are also described in this chapter. It's possible to handle also interactive jobs via PBS Pro.

The chapter is divided to the following subsections:

5.1 General information about the batch system

5.2 Commands

      5.2.1 Submitting jobs: qsub

      5.2.2 Deleting jobs: qdel

      5.2.3 Job launching command: aprun (and ALPS)

      5.2.4 Status of jobs, queues and batch server: qstat

5.3 Parallel batch jobs (Example batch job scripts)

5.4 Monitoring and displaying job status