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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | USAGE | PERMISSIONS | SEE ALSO | AUTHOR | COPYRIGHT | AVAILABILITY | COLOPHON |
TASKSET(1) User Commands TASKSET(1)
taskset - set or retrieve a process's CPU affinity
taskset [options] mask command [argument...]
taskset [options] -p [mask] pid
taskset is used to set or retrieve the CPU affinity of a running
process given its pid, or to launch a new command with a given CPU
affinity. CPU affinity is a scheduler property that "bonds" a
process to a given set of CPUs on the system. The Linux scheduler
will honor the given CPU affinity and the process will not run on any
other CPUs. Note that the Linux scheduler also supports natural CPU
affinity: the scheduler attempts to keep processes on the same CPU as
long as practical for performance reasons. Therefore, forcing a
specific CPU affinity is useful only in certain applications.
The CPU affinity is represented as a bitmask, with the lowest order
bit corresponding to the first logical CPU and the highest order bit
corresponding to the last logical CPU. Not all CPUs may exist on a
given system but a mask may specify more CPUs than are present. A
retrieved mask will reflect only the bits that correspond to CPUs
physically on the system. If an invalid mask is given (i.e., one
that corresponds to no valid CPUs on the current system) an error is
returned. The masks may be specified in hexadecimal (with or without
a leading "0x"), or as a CPU list with the --cpu-list option. For
example,
0x00000001 is processor #0,
0x00000003 is processors #0 and #1,
0xFFFFFFFF is processors #0 through #31,
32 is processors #1, #4, and #5,
--cpu-list 0-2,6
is processors #0, #1, #2, and #6.
When taskset returns, it is guaranteed that the given program has
been scheduled to a legal CPU.
-a, --all-tasks
Set or retrieve the CPU affinity of all the tasks (threads)
for a given PID.
-c, --cpu-list
Interpret mask as numerical list of processors instead of a
bitmask. Numbers are separated by commas and may include
ranges. For example: 0,5,8-11.
-p, --pid
Operate on an existing PID and do not launch a new task.
-V, --version
Display version information and exit.
-h, --help
Display help text and exit.
The default behavior is to run a new command with a given affinity
mask:
taskset mask command [arguments]
You can also retrieve the CPU affinity of an existing task:
taskset -p pid
Or set it:
taskset -p mask pid
A user can change the CPU affinity of a process belonging to the same
user. A user must possess CAP_SYS_NICE to change the CPU affinity of
a process belonging to another user. A user can retrieve the
affinity mask of any process.
chrt(1), nice(1), renice(1), sched_getaffinity(2),
sched_setaffinity(2)
See sched(7) for a description of the Linux scheduling scheme.
Written by Robert M. Love.
Copyright © 2004 Robert M. Love. This is free software; see the
source for copying conditions. There is NO warranty; not even for
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
The taskset command is part of the util-linux package and is
available from https://www.kernel.org/pub/linux/utils/util-linux/.
This page is part of the util-linux (a random collection of Linux
utilities) project. Information about the project can be found at
⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩. If you have a
bug report for this manual page, send it to
util-linux@vger.kernel.org. This page was obtained from the
project's upstream Git repository
⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
2017-07-05. If you discover any rendering problems in this HTML ver‐
sion of the page, or you believe there is a better or more up-to-date
source for the page, or you have corrections or improvements to the
information in this COLOPHON (which is not part of the original man‐
ual page), send a mail to man-pages@man7.org
util-linux August 2014 TASKSET(1)
Pages that refer to this page: chrt(1), sched_setaffinity(2), cpuset(7), sched(7), migratepages(8)