NAME

       taskset - set or retrieve a process's CPU affinity

SYNOPSIS

       taskset [options] mask command [argument...]

       taskset [options] -p [mask] pid

DESCRIPTION

       The taskset command 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.

       --cpu-list 0-10:2
           is processors #0, #2, #4, #6, #8 and #10. The suffix ":N" specifies stride in the range, for example
           0-10:3 is interpreted as 0,3,6,9 list.

       When taskset returns, it is guaranteed that the given program has been scheduled to a legal CPU.

OPTIONS

       -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.

USAGE

       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

PERMISSIONS

       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.

AUTHORS

       Written by Robert M. Love.

COPYRIGHT

       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.

SEE ALSO

       chrt(1), nice(1), renice(1), sched_getaffinity(2), sched_setaffinity(2)

       See sched(7) for a description of the Linux scheduling scheme.

REPORTING BUGS

       For bug reports, use the issue tracker at https://github.com/karelzak/util-linux/issues.

AVAILABILITY

       The taskset command is part of the util-linux package which can be downloaded from Linux Kernel Archive
       <https://www.kernel.org/pub/linux/utils/util-linux/>.