RENICE(8)
NAME
renice − alter priority of running processes
USAGE
/etc/renice priority [ [ −p ] pid ] [ [ −g ] pgrp ] [ [ −u ] user ]
DESCRIPTION
Renice changes the scheduling priority of one or more running processes. Renice will operate on processes identified by process IDs, process group IDs, or usernames. Running renice on a process group causes all processes in the group to have their scheduling priority altered. Renice followed by a username causes all processes owned by that user to have their scheduling priority altered.
By default, the processes to be affected are specified by their process IDs.
Users can increase the priority of their own processes, i.e., make them run slower, by setting priority to a positive integer in the range 0 to PRIO_MIN (20). Setting the priority to a negative integer in the range zero to PRIO_MAX (-20) causes processes to run more quickly.
Useful priorities are:
19 (the processes will run only when nothing else on the system wants to)
0 (the “base” scheduling priority)
negative numbers (to make processes run faster)
OPTIONS
−g forces renice to interpret the next number as the process ID of a group of processes to be affected.
−u allows you to specify all the processes of a certain user or users.
−p resets the interpretation to process IDs (the default). This may be necessary when several options are strung together on one command line (see below).
NOTES
If you give the process a negative priority, the process cannot be interrupted. To interrupt the process, you must change the priority to a number greater than zero.
Unless you are the super-user, you can’t increase the scheduling priorities of your own processes, even if you were the one who decreased the priorities in the first place.
EXAMPLE
/etc/renice +1 987 −u daemon root −p 32 decreases the priority of process IDs 987 and 32, as well as that of all processes owned by users daemon and root.
FILES
/etc/passwd file that maps user names to user IDs