sys-utils/renice.1

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  32 .\"     @(#)renice.8    8.1 (Berkeley) 6/9/93
  33 .\"
  34 .Dd June 9, 1993
  35 .Dt RENICE 1
  36 .Os BSD 4
  37 .Sh NAME
  38 .Nm renice
  39 .Nd alter priority of running processes
  40 .Sh SYNOPSIS
  41 .Nm renice
  42 .Ar priority
  43 .Oo
  44 .Op Fl p
  45 .Ar pid ...
  46 .Oc
  47 .Oo
  48 .Op Fl g
  49 .Ar pgrp ...
  50 .Oc
  51 .Oo
  52 .Op Fl u
  53 .Ar user ...
  54 .Oc
  55 .Sh DESCRIPTION
  56 .Nm Renice
  57 alters the
  58 scheduling priority of one or more running processes.
  59 The following
  60 .Ar who
  61 parameters are interpreted as process ID's, process group
  62 ID's, or user names.
  63 .Nm Renice Ns 'ing
  64 a process group causes all processes in the process group
  65 to have their scheduling priority altered.
  66 .Nm Renice Ns 'ing
  67 a user causes all processes owned by the user to have
  68 their scheduling priority altered.
  69 By default, the processes to be affected are specified by
  70 their process ID's.
  71 .Pp
  72 Options supported by
  73 .Nm renice :
  74 .Bl -tag -width Ds
  75 .It Fl g
  76 Force
  77 .Ar who
  78 parameters to be interpreted as process group ID's.
  79 .It Fl u
  80 Force the
  81 .Ar who
  82 parameters to be interpreted as user names.
  83 .It Fl p
  84 Resets the
  85 .Ar who
  86 interpretation to be (the default) process ID's.
  87 .El
  88 .Pp
  89 For example,
  90 .Bd -literal -offset
  91 renice +1 987 -u daemon root -p 32
  92 .Ed
  93 .Pp
  94 would change the priority of process ID's 987 and 32, and
  95 all processes owned by users daemon and root.
  96 .Pp
  97 Users other than the super-user may only alter the priority of
  98 processes they own,
  99 and can only monotonically increase their ``nice value''
 100 within the range 0 to
 101 .Dv PRIO_MAX
 102 (20).
 103 (This prevents overriding administrative fiats.)
 104 The super-user
 105 may alter the priority of any process
 106 and set the priority to any value in the range
 107 .Dv PRIO_MIN
 108 (\-20)
 109 to
 110 .Dv PRIO_MAX .
 111 Useful priorities are:
 112 20 (the affected processes will run only when nothing else
 113 in the system wants to),
 114 0 (the ``base'' scheduling priority),
 115 anything negative (to make things go very fast).
 116 .Sh FILES
 117 .Bl -tag -width /etc/passwd -compact
 118 .It Pa /etc/passwd
 119 to map user names to user ID's
 120 .El
 121 .Sh SEE ALSO
 122 .Xr getpriority 2 ,
 123 .Xr setpriority 2
 124 .Sh BUGS
 125 Non super-users can not increase scheduling priorities of their own processes,
 126 even if they were the ones that decreased the priorities in the first place.
 127 .br
 128 The Linux kernel (at least version 2.0.0) and linux libc (at least
 129 version 5.2.18) does not agree entirely on what the specifics of the
 130 systemcall interface to set nice values is.  Thus causes renice to
 131 report bogus previous nice values.
 132 .Sh HISTORY
 133 The
 134 .Nm
 135 command appeared in
 136 .Bx 4.0 .