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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  memory  do-
     mains,  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  specified
     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 target 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  domains
     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 specified 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  available
		  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  num-
		  berd domain.

     -g 	  Causes  cpuset  to print either a list of valid CPUs or, using
		  -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 operation.

     -l cpu-list  Specifies  a list of CPUs to apply to a target.  Specification
		  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), prefer and  inter-
		  leave  (il).	 First-touch  allocates on the local domain when
		  memory is available.	 Round-robin  alternates  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 avail-
		  able 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 allowed 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 ports 15.quarterly	  July 3, 2018			       CPUSET(1)

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