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RENICE(1)			 User Commands			     RENICE(1)

       renice - alter priority of running processes

       renice [-n] priority [-gpu] identifier...

       renice alters the scheduling priority of one or more running processes.
       The first argument is the priority value to be used.  The  other	 argu-
       ments  are  interpreted as process IDs (by default), process group IDs,
       user IDs, or user names.	 renice'ing a process group  causes  all  pro-
       cesses  in the process group to have their scheduling priority altered.
       renice'ing a user causes all processes owned by the user to have	 their
       scheduling priority altered.

       -n, --priority priority
	      Specify  the  scheduling	priority  to  be used for the process,
	      process group, or user.  Use of the option -n or	--priority  is
	      optional, but when used it must be the first argument.

       -g, --pgrp pgid...
	      Force  the  succeeding  arguments	 to  be interpreted as process
	      group IDs.

       -u, --user name_or_uid...
	      Force the succeeding arguments to be interpreted as usernames or

       -p, --pid pid...
	      Force  the succeeding arguments to be interpreted as process IDs
	      (the default).

       -h, --help
	      Display a help text.

       -V, --version
	      Display version information.

       The following command would change the priority of the  processes  with
       PIDs 987 and 32, plus all processes owned by the users daemon and root:

	      renice +1 987 -u daemon root -p 32

       Users  other  than  the	super-user may only alter the priority of pro-
       cesses they own, and  can  only	monotonically  increase	 their	``nice
       value''	(for  security	reasons)  within the range 0 to PRIO_MAX (20),
       unless a nice resource limit is set (Linux  2.6.12  and	higher).   The
       super-user  may	alter the priority of any process and set the priority
       to any value in the range PRIO_MIN (-20) to PRIO_MAX.   Useful  priori-
       ties are: 20 (the affected processes will run only when nothing else in
       the system wants to), 0 (the ``base''  scheduling  priority),  anything
       negative (to make things go very fast).

	      to map user names to user IDs

       getpriority(2), setpriority(2)

       Non  super-users	 can  not  increase scheduling priorities of their own
       processes, even if they were the ones that decreased the priorities  in
       the first place.

       The Linux kernel (at least version 2.0.0) and linux libc (at least ver-
       sion 5.2.18) does not agree entirely on what the specifics of the  sys-
       temcall	interface to set nice values is.  Thus causes renice to report
       bogus previous nice values.

       The renice command appeared in 4.0BSD.

       The renice command is part of the util-linux package and	 is  available
       from  Linux  Kernel Archive <ftp://ftp.kernel.org/pub/linux/utils/util-

util-linux			September 2011			     RENICE(1)