Job Script Directives Reference¶

This page is a full reference for PBS directives and environment variables used in Vega job scripts. For a practical introduction to job submission, see Job Submission.

PBS Directives¶

Directives are placed at the top of your job script, after the shebang (#!/bin/bash) and before any executable commands. Each line must begin with #PBS.

Directive	Description	Example
`-N`	Job name	`-N LES_Scramjet`
`-q`	Queue to submit to	`-q longq`
`-l nodes=#:ppn=#`	Number of nodes and cores per node	`-l nodes=2:ppn=192`
`-l mem=#gb`	Total memory requested	`-l mem=16gb`
`-l walltime=HH:MM:SS`	Maximum runtime	`-l walltime=02:00:00`
`-o <file>`	File to write standard output	`-o my_job.log`
`-e <file>`	File to write standard error	`-e my_job_error.log`
`-j oe`	Merge standard output and error into one file	`-j oe`
`-M <email>`	Email address for notifications	`-M user@domain.com`
`-m <option>`	When to send email: `b`egin, `e`nd, `a`bort, `n`one	`-m bea`
`-A <account>`	Billing or project account	`-A my_project`
`-l gpus=#`	Number of GPUs to request (GPU nodes only)	`-l nodes=1:ppn=192:gpus=4`

PBS Environment Variables¶

When the scheduler runs your job, it automatically sets the following environment variables. These can be referenced anywhere in your job script.

Variable	Description
`$PBS_NP`	Total number of cores allocated to the job
`$PBS_NUM_NODES`	Number of nodes allocated
`$PBS_NUM_PPN`	Number of cores per node
`$PBS_JOBID`	Job ID assigned by TORQUE (e.g., `12345.vegabk.head.cm.vega.era`)
`$PBS_JOBNAME`	Job name as set by `-N`
`$PBS_QUEUE`	Queue the job is running in
`$PBS_NODEFILE`	Path to a file listing all allocated compute node hostnames
`$PBS_GPUFILE`	Path to a file listing allocated GPUs (GPU jobs only)
`$PBS_O_WORKDIR`	Directory from which the job was submitted
`$PBS_O_HOME`	Home directory of the submitting user
`$PBS_O_HOST`	Hostname of the node running the job