In Unix, how should I submit CPU-intensive jobs?
Several mechanisms are available for handling large jobs in Unix, including reducing the priority of a process, running a process in the background, and, on some systems, submitting batch jobs.
On this page:
For information about the
commands, see In Unix, what are the at and batch commands, and how do I use them to submit non-interactive job requests?
For information about using TORQUE (based on OpenPBS) on Quarry and Mason at IU, see What is TORQUE, and how do I use it to submit and manage jobs on a high-performance computing system?
Although Big Red II uses TORQUE for resource management, Big Red II job scripts must contain commands and directives specific to Big Red II's programming environment and system architecture; see How do I run batch jobs on Big Red II at IU?
Changing a job's priority and running a job in the background
To immediately execute a process at a lower priority, use the
nice command. For example, to run a program called
a.out at lower priority, at the Unix shell
To let the job run in the background (so you can keep working
interactively), add an ampersand (
& ) to
the end of the command line:
When the job is complete, you will see something similar to this: Done ls (csh/tcsh)
For more on the
nice command, see the manual
(man) page, which you can access by entering:
For more information on how to work with background processes, see
the man page for your shell (e.g.,
At Indiana University, for personal or departmental Linux or Unix systems support, see At IU, how do I get support for Linux or Unix?
Last modified on October 02, 2013.