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CPUSET(1)		     General Commands Manual		       CPUSET(1)

NAME
     cpuset -- configure processor sets

SYNOPSIS
     cpuset [-l cpu-list] [-s setid] cmd
     cpuset [-l cpu-list] [-s setid] -p pid
     cpuset [-cr] [-l cpu-list] [-p pid | -r tid | -s setid]
     cpuset [-cgir] [-p pid | -r tid | -s setid]

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 query infor-
     mation about processor binding, sets, and available processors in the  sys-
     tem.

     cpuset  requires  a target to modify or query.  The target may be specified
     as a command, process id, thread id, or a cpuset id.  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.

     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 	  The requested operation should reference the cpuset  available
		  via the target specifier.

     -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.

     -l cpu-list  Specifies  a list of CPUs to apply to a target.  Specification
		  may include numbers seperated by '-'	for  ranges  and  commas
		  separating individual numbers.

     -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.

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>

SEE ALSO
     cpuset(2)

HISTORY
     The cpuset command first appeared in FreeBSD 7.1.

AUTHORS
     Jeffrey Roberson <jeff@FreeBSD.org>

FreeBSD 7.1			  March 2, 2008 		       CPUSET(1)
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