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33 .Nd alter priority of running processes
37 .Op Oo Fl gpu Oc Ar target
40 .Op Oo Fl gpu Oc Ar target
45 scheduling priority of one or more running processes.
48 parameters are interpreted as process ID's (the default), process group
49 ID's, user ID's or user names.
52 of a process group causes all processes in the process group
53 to have their scheduling priority altered.
56 of a user causes all processes owned by the user to have
57 their scheduling priority altered.
59 The following options are available:
60 .Bl -tag -width indent
62 Instead of changing the specified processes to the given priority,
63 interpret the following argument as an increment to be applied to
64 the current priority of each process.
68 parameters as process group ID's.
72 parameters as process ID's (the default).
76 parameters as user names or user ID's.
79 Users other than the super-user may only alter the priority of
81 and can only monotonically increase their ``nice value''
85 (This prevents overriding administrative fiats.)
87 may alter the priority of any process
88 and set the priority to any value in the range
93 Useful priorities are:
94 20 (the affected processes will run only when nothing else
95 in the system wants to),
96 0 (the ``base'' scheduling priority),
97 anything negative (to make things go very fast).
99 .Bl -tag -width /etc/passwd -compact
101 to map user names to user ID's
104 Change the priority of process ID's 987 and 32, and
105 all processes owned by users daemon and root.
107 .Dl "renice +1 987 -u daemon root -p 32"
124 Non super-users cannot increase scheduling priorities of their own processes,
125 even if they were the ones that decreased the priorities in the first place.