System Interface Guide

Thepriocntl(1) Command

The priocntl(1) utility performs four different control functions on the scheduling of a process:

priocntl -l

displays configuration information  

priocntl -d

displays the scheduling parameters of processes 

priocntl -s

sets the scheduling parameters of processes 

priocntl -e

executes a command with the specified scheduling parameters  

The following are some examples of using priocntl(1).

The output of the -l option for the default configuration is:

$ priocntl -d -i all

SYS (System Class)

TS (Time Sharing)
Configured TS User Priority Range -20 through 20

RT (Real Time)
Maximum Configured RT Priority: 59

An example of displaying information on all processes:

$ priocntl -d -i all

An example of displaying information on all time-sharing processes:

$ priocntl -d -i class TS

An example of displaying information on all processes with user ID 103 or 6626:

$ priocntl -d -i uid 103 6626

An example of making the process with ID 24668 a real-time process with default parameters:

$ priocntl -s -c RT -i pid 24668

An example of making 3608 RT with priority 55 and a one-fifth second time slice:

$ priocntl -s -c RT -p 55 -t 1 -r 5 -i pid 3608

An example of changing all processes into time-sharing processes:

$ priocntl -s -c TS -i all

For uid 1122, reduce TS user priority and user priority limit to -10:

$ priocntl -s -c TS -p -10 -m -10 -i uid 1122

An example of starting a real-time shell with default real-time priority:

$ priocntl -e -c RT /bin/sh

An example of running make with a time-sharing user priority of -10:

$ priocntl -e -c TS -p -10 make bigprog

priocntl(1) subsumes the function of nice(1). nice works only on time-sharing processes and uses higher numbers to assign lower priorities. The example above is equivalent to using nice(1) to set an "increment" of 10:

$ nice -10 make bigprog