Redhat Enterprise Linux / RHEL

How do I set the real time scheduling priority of a process?

In the event that a process is not achieving the desired performance performance benchmarks, it can be helpful to set CPU affinity, real-time scheduling policy and real-time scheduling priority. Experimenting with different options using the taskset and chrt commands can help determine if this approach will provide the desired results.

The taskset sets CPU affinity for a process. The chrt sets real time scheduling options. The two commands can be used in tandem. For example:

 taskset -c 2-3 chrt -f 1 <command>

The above usage would force <command> to run on CPUs 2 through 3, using the “fifo” scheduling policy at priority level 1. The results of using these options depend on the workload of the application, as well as the load of the system in general.

For more information on the taskset and chrt commands, see their respective man pages. For more information on setting these attributes within an application, rather than when launching the application, see man 2 sched_setaffinity and man 2 sched_setscheduler.

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How do I set default password expiration for new accounts?

To set the default password expiration when creating new accounts on Red Hat® Enterprise Linux®, edit the /etc/login.defs file.

For example, to set the default maximum number of days a password may be used, change the following parameter in login.defs:


To set the default number of days warning given before a password expires, change the following parameter in login.defs:


Please refer the man page of login.defs for more parameters about default password expiration.

linux/redhat.txt · Last modified: 2009/05/25 00:35 (external edit)
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