NPRI(1)NPRI(1)NAMEnpri - modify the scheduling priority of a process
SYNOPSISnpri [ -w ] | [ -r priority [ -s policy ] ] | [ -n nice ] | [ -t slice ]
[ -p pid ]
npri [ -w ] | [ -r priority [ -s policy ] ] | [ -n nice ] | [ -t slice ]
[ cmd args ... ]
DESCRIPTION
This command allows the super-user to modify certain scheduling
parameters of a process or to create a new process with specific
scheduling parameters. For a detailed description of how the parameters
affect the scheduling of a process, please see the sched_setscheduler(2)
manual page. If npri is invoked without reference to a specific process
or command to execute, it simply invokes a copy of the user's shell, as
specified by the SHELL environment variable, with the scheduling
characteristics specified.
OPTIONS
The following options are supported:
-w This option makes the process weightless. A weightless process
executes at a priority strictly less than any other process in
the system.
-r priority
This option sets the priority of a process. For real-time
policies (see -s) the valid priority range is 0 to 255, while
the time-share policy accepts priorities ranging from 1 to 40.
When used without the -s option, npri will attempt to reset the
priority of the specified process according to its current (or
inherited) policy.
-s policy This option sets the scheduling policy of a process. The
supported policies are FIFO and RR for real-time and TS for
timeshare. Both the policy and priority will be inherited by
any new children of the process. Care should be used when
assigning real-time policies, since such a process is not
preemptable by normal interactive processes. Refer to
realtime(5) for more details.
-n nice This option sets the absolute nice value of a process. The
nice value affects how normal UNIX priority calculations are
made. The allowable range of nice values is 0 to 39. Refer to
nice(2) for more information.
-t slice This option sets the time-slice for the process, in terms of
the basic kernel clock frequency (called ticks). The 4D Series
machines use a clock frequency of 100 hertz, so one tick is 10
milliseconds. For example, a slice value of 3 gives a 30
millisecond time slice. The time slice value will be inherited
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by any new children of the process.
-h priority
This is the older method used to set priority previous to the
introduction of the -r and -s options. It is still available
for backward compatibility.
-p pid This option names a specific process whose priority is to be
altered. This makes it possible to change priorities of a
running process.
SEE ALSOnice(2), schedctl(2), sched_setscheduler(2), realtime(5).
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