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TASKSET(1) User Commands TASKSET(1)


taskset - set or retrieve a process's CPU affinity


taskset [options] mask command [argument...]
taskset [options] -p [maskpid



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,

is processor #0,
is processors #0 and #1,
is processors #0 through #31,
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.



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.
Display version information and exit.
Display help text and exit.


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.




August 2014 util-linux