renice is a
*NIX command used to change the priority of a particular process, group of processes, or
user. Its parameters:
/usr/bin/renice [ -n increment | priority ] [ [ -p ] pid ... ]
[ [ -g ] pgrp ... ] [ [ -u ] user ... ]
-n is followed by a positive or negative
integer indicating the change in
scheduling priority.
Alternately, the
priority can be explicitly defined.
-p is used to specify that the parameters of the command should be interpreted as a
pid
-g specifies instead that the parameters be read as a group of processes.
-u means that the the changes should be exacted on a
user.
Only
superusers are able to renice all processes, other users can only change the priority of processes belonging to them and only within a certain range so as not to override administrative processes.
Source: http://www.mcsr.olemiss.edu/cgi-bin/man-cgi?renice+1