1CHRT(1)                       Linux User's Manual                      CHRT(1)
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NAME

6       chrt - manipulate real-time attributes of a process
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SYNOPSIS

9       chrt [options] prio command [arg]...
10       chrt [options] -p [prio] pid
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DESCRIPTION

13       chrt(1)  sets  or  retrieves  the real-time scheduling attributes of an
14       existing PID or runs COMMAND with the given  attributes.   Both  policy
15       (one  of SCHED_OTHER, SCHED_FIFO, SCHED_RR, SCHED_BATCH, or SCHED_IDLE)
16       and priority can be set and retrieved.
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18       The SCHED_BATCH policy is supported since Linux 2.6.16. The  SCHED_IDLE
19       policy is supported since Linux 2.6.23.
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OPTIONS

22       -p, --pid
23              operate on an existing PID and do not launch a new task
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25       -b, --batch
26              set scheduling policy to SCHED_BATCH (Linux specific)
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28       -f, --fifo
29              set scheduling policy to SCHED_FIFO
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31       -i, --idle
32              set schedulng policy to SCHED_IDLE (Linux specific)
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34       -m, --max
35              show minimum and maximum valid priorities, then exit
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37       -o, --other
38              set policy scheduling policy to SCHED_OTHER
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40       -r, --rr
41              set scheduling policy to SCHED_RR (the default)
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43       -h, --help
44              display usage information and exit
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46       -v, --version
47              output version information and exit
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USAGE

50       The default behavior is to run a new command::
51              chrt prio command [arguments]
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53       You can also retrieve the real-time attributes of an existing task:
54              chrt -p pid
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56       Or set them:
57              chrt -p prio pid
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PERMISSIONS

60       A user must possess CAP_SYS_NICE to change the scheduling attributes of
61       a process.  Any user can retrieve the scheduling information.
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NOTES

64       Only SCHED_FIFO, SCHED_OTHER and SCHED_RR are  part  of  POSIX  1003.1b
65       Process  Scheduling.  The other scheduling attributes may be ignored on
66       some systems.
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AUTHOR

69       Written by Robert M. Love.
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72       Copyright © 2004 Robert M. Love
73       This is free software; see the source for copying conditions.  There is
74       NO  warranty;  not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR
75       PURPOSE.
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SEE ALSO

78       taskset(1), nice(1), renice(1)
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80       See sched_setscheduler(2) for a description  of  the  Linux  scheduling
81       scheme.
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AVAILABILITY

84       The  chrt command is part of the util-linux-ng package and is available
85       from ftp://ftp.kernel.org/pub/linux/utils/util-linux-ng/.
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89schedutils                         Apr 2003                            CHRT(1)
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