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CPUSET(1)		    General Commands Manual		     CPUSET(1)

NAME
       cpuset -- configure processor sets

SYNOPSIS
       cpuset [-l cpu-list] [-n	policy:domain-list] [-s	setid] cmd ...
       cpuset [-l cpu-list] [-n	policy:domain-list] [-s	setid] -p pid
       cpuset [-c] [-l cpu-list] [-n policy:domain-list] -C -p pid
       cpuset	   [-c]	     [-l     cpu-list]	   [-n	   policy:domain-list]
	      [-j jail | -p pid	| -t tid | -s setid | -x irq]
       cpuset				 -g				[-cir]
	      [-d domain | -j jail | -p	pid | -t tid | -s setid	| -x irq]

DESCRIPTION
       The  cpuset  command can	be used	to assign processor sets to processes,
       run commands constrained	to a given set or list of processors and  mem-
       ory  domains,  and  query  information  about processor binding,	memory
       binding and policy, sets, and available processors and  memory  domains
       in the system.

       cpuset  requires	a target to modify or query.  The target may be	speci-
       fied as a command, process id, thread id, a cpuset id, an irq, a	 jail,
       or a NUMA domain.  Using	-g the target's	set id or mask may be queried.
       Using  -l or -s the target's CPU	mask or	set id may be set.  If no tar-
       get is specified, cpuset	operates on itself.  Not all  combinations  of
       operations and targets are supported.  For example, you may not set the
       id of an	existing set or	query and launch a command at the same time.

       There  are two sets applicable to each process and one private mask per
       thread.	Every process in the system belongs to a cpuset.   By  default
       processes  are  started	in set 1.  The mask or id may be queried using
       -c.  Each thread	also has a private mask	of CPUs	it is allowed  to  run
       on  that	must be	a subset of the	assigned set.  And finally, there is a
       root set, numbered 0, that is immutable.	 This last set is the list  of
       all possible CPUs in the	system and is queried using -r.

       Most  sets include NUMA memory domain and policy	information.  This can
       be inspected with -g and	set with -n.  This will	specify	which NUMA do-
       mains are visible to the	process	and affect where anonymous memory  and
       file  pages  will  be  stored on	first access.  Files accessed first by
       other processes may specify conflicting policy.

       When running a command it may join a set	specified with -s otherwise  a
       new  set	is created.  In	addition, a mask for the command may be	speci-
       fied using -l.  When used in conjunction	with -c	the mask modifies  the
       supplied	or created set rather than the private mask for	the thread.

       The options are as follows:

       -C	    Create  a new cpuset and assign the	target process to that
		    set.

       -c	    The	requested operation should reference the cpuset	avail-
		    able via the target	specifier.

       -d domain    Specifies a	NUMA domain id as the target of	the operation.
		    This can only be used to query the cpus  visible  in  each
		    numberd domain.

       -g	    Causes cpuset to print either a list of valid CPUs or, us-
		    ing	-i, the	id of the target.

       -i	    When  used with the	-g option print	the id rather than the
		    valid mask of the target.

       -j jail	    Specifies a	jail id	or name	as the target  of  the	opera-
		    tion.

       -l cpu-list  Specifies a	list of	CPUs to	apply to a target.  Specifica-
		    tion  may  include numbers separated by '-'	for ranges and
		    commas separating individual numbers.  A special  list  of
		    "all" may be specified in which case the list includes all
		    CPUs from the root set.

       -n policy:domain-list
		    Specifies a	list of	domains	and allocation policy to apply
		    to	a  target.   Ranges  may be specified as in -l.	 Valid
		    policies include first-touch (ft), round-robin (rr),  pre-
		    fer	and interleave (il).  First-touch allocates on the lo-
		    cal	 domain	 when memory is	available.  Round-robin	alter-
		    nates between every	possible domain	page at	a  time.   The
		    prefer  policy  accepts  only  a single domain in the set.
		    The	parent of the set is consulted if the preferred	domain
		    is unavailable.  Interleave	operates like round-robin with
		    an implementation defined stripe width.  See  domainset(9)
		    for	more details on	policies.

       -p pid	    Specifies a	pid as the target of the operation.

       -s setid	    Specifies a	set id as the target of	the operation.

       -r	    The	 requested  operation  should  reference  the root set
		    available via the target specifier.

       -t tid	    Specifies a	thread id as the target	of the operation.

       -x irq	    Specifies an irq as	the target of the operation.

EXIT STATUS
       The cpuset utility exits	0 on success, and >0 if	an error occurs.

EXAMPLES
       Create a	new group with CPUs 0-4	inclusive and run /bin/sh on it:
	     cpuset -c -l 0-4 /bin/sh

       Query the mask of CPUs the <sh pid> is allowed to run on:
	     cpuset -g -p <sh pid>

       Restrict	/bin/sh	to run on CPUs 0 and 2 while its group	is  still  al-
       lowed to	run on CPUs 0-4:
	     cpuset -l 0,2 -p <sh pid>

       Modify the cpuset /bin/sh belongs to restricting	it to CPUs 0 and 2:
	     cpuset -l 0,2 -c -p <sh pid>

       Modify  the  cpuset  all	 threads are in	by default to contain only the
       first 4 CPUs, leaving the rest idle:
	     cpuset -l 0-3 -s 1

       Print the id of the cpuset /bin/sh is in:
	     cpuset -g -i -p <sh pid>

       Move the	pid into the specified cpuset setid so it may be managed  with
       other pids in that set:
	     cpuset -s <setid> -p <pid>

       Create  a  new  cpuset  that is restricted to CPUs 0 and	2 and move pid
       into the	new set:
	     cpuset -C -c -l 0,2 -p <pid>

SEE ALSO
       nproc(1), cpuset(2), rctl(8)

HISTORY
       The cpuset command first	appeared in FreeBSD 7.1.

AUTHORS
       Jeffrey Roberson	<jeff@FreeBSD.org>

FreeBSD	13.2			 July 3, 2018			     CPUSET(1)

NAME | SYNOPSIS | DESCRIPTION | EXIT STATUS | EXAMPLES | SEE ALSO | HISTORY | AUTHORS

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