The priocntl Command

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

See the manual page for details of priocntl. The following are some examples of using priocntl.

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

$ priocntl -l 
CONFIGURED CLASSES 
==================

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

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

$ nice -10 make bigprog