Provided by: numactl_2.0.3-1_i386 bug

NAME

       numactl - Control NUMA policy for processes or shared memory

SYNOPSIS

       numactl [ --interleave nodes ] [ --preferred node ] [ --membind nodes ]
       [ --cpunodebind nodes ] [ --physcpubind cpus ] [  --localalloc  ]  [--]
       command {arguments ...}
       numactl --show
       numactl --hardware
       numactl [ --huge ] [ --offset offset ] [ --shmmode shmmode ] [ --length
       length ] [ --strict ]
       [ --shmid id ] --shm shmkeyfile | --file tmpfsfile
       [ --touch ] [ --dump ] [ --dump-nodes ] memory policy

DESCRIPTION

       numactl runs processes  with  a  specific  NUMA  scheduling  or  memory
       placement  policy.   The policy is set for command and inherited by all
       of its children.  In addition it can set persistent policy  for  shared
       memory segments or files.

       Use -- before command if using command options that could be confused
              with numactl options.

       Policy settings are:

       --interleave=nodes, -i nodes
              Set  a  memory interleave policy. Memory will be allocated using
              round robin on nodes.  When memory cannot be  allocated  on  the
              current  interleave  target  fall back to other nodes.  Multiple
              nodes  may  be  specified   on   --interleave,   --membind   and
              --cpunodebind.   You may specify "all", which means all nodes in
              the current cpuset.  nodes may be specified as N,N,N or  N-N  or
              N,N-N  or  N-N,N-N and so forth.  Relative nodes may be specifed
              as +N,N,N or  +N-N or +N,N-N and so forth. The + indicates  that
              the  node  numbers  are  relative to the process’ set of allowed
              nodes in its current cpuset.   A  !N-N  notation  indicates  the
              inverse  of  N-N,  in other words all nodes except N-N.  If used
              with + notation, specify !+N-N.

       --membind=nodes, -m nodes
              Only allocate memory from  nodes.   Allocation  will  fail  when
              there  is not enough memory available on these nodes.  nodes may
              be specified as noted above.

       --cpunodebind=nodes, -N nodes
              Only execute command on the CPUs of nodes.  Note that nodes  may
              consist  of  multiple  CPUs.   nodes  may  be specified as noted
              above.

       --physcpubind=cpus, -C cpus
              Only execute process on cpus.  This accepts physical cpu numbers
              as  shown  in the processor fields of /proc/cpuinfo, or relative
              cpus as in relative to the  current  cpuset.   You  may  specify
              "all",  which  means  all  cpus in the current cpuset.  Physical
              cpus may be specified as N,N,N or  N-N or N,N-N or  N-N,N-N  and
              so  forth.   Relative cpus may be specifed as +N,N,N or  +N-N or
              +N,N-N and so forth. The + indicates that the  cpu  numbers  are
              relative  to  the  process’  set  of allowed cpus in its current
              cpuset.  A !N-N notation indicates the inverse of N-N, in  other
              words  all  cpus  except  N-N.  If used with + notation, specify
              !+N-N.

       --localalloc, -l
              Always allocate on the current node.

       --preferred=node
              Preferably allocate memory on node,  but  if  memory  cannot  be
              allocated  there  fall  back  to other nodes.  This option takes
              only a single node number.  Relative notation may be used.

       --show, -s
              Show NUMA policy settings of the current process.

       --hardware, -H
              Show inventory of available nodes on the system.

       Numactl can set up policy for a SYSV shared memory segment or a file in
       shmfs/hugetlbfs.

       This policy is persistent and will be used by all  mappings  from  that
       shared  memory.  The  order of options matters here.  The specification
       must at least include either of --shm, --shmid, --file to  specify  the
       shared  memory segment or file and a memory policy like described above
       ( --interleave, --localalloc, --prefered, --membind ).

       --huge
       When creating a SYSV shared memory segment use huge pages.  Only  valid
       before --shmid or --shm

       --offset
       Specify  offset into the shared memory segment. Default 0.  Valid units
       are m (for MB), g (for GB), k (for KB), otherwise it specifies bytes.

       --strict
       Give an error when a page in the policied area  in  the  shared  memory
       segment already was faulted in with a conflicting policy. Default is to
       silently ignore this.

       --shmmode shmmode
       Only valid before --shmid  or  --shm  When  creating  a  shared  memory
       segment set it to numeric mode shmmode.

       --length length
       Apply  policy  to length range in the shared memory segment or make the
       segment length long Default is to use  the  remaining  length  Required
       when a shared memory segment is created and specifies the length of the
       new segment then. Valid units are m (for MB), g (for GB), k  (for  KB),
       otherwise it specifies bytes.

       --shmid id
       Create or use an shared memory segment with numeric ID id

       --shm shmkeyfile
       Create  or  use  an  shared memory segment, with the ID generated using
       ftok(3) from shmkeyfile

       --file tmpfsfile
       Set policy for a file in tmpfs or hugetlbfs

       --touch
       Touch pages to enforce policy early. Default is to not touch them,  the
       policy is applied when an applications maps and accesses a page.

       --dump
       Dump policy in the specified range.

       --dump-nodes
       Dump all nodes of the specific range (very verbose!)

       Valid node specifiers

       all                 All nodes
       number              Node number
       number1{,number2}   Node number1 and Node number2
       number1-number2     Nodes from number1 to number2
       ! nodes             Invert selection of the following specification.

EXAMPLES

       numactl --physcpubind=+0-4,8-12 myapplic arguments Run myapplic on cpus
       0-4 and 8-12 of the current cpuset.

       numactl --interleave=all bigdatabase arguments Run  big  database  with
       its memory interleaved on all CPUs.

       numactl  --cpubind=0  --membind=0,1  process Run process on node 0 with
       memory allocated on node 0 and 1.

       numactl --cpubind=0 --membind=0,1 -- process -l Run process  as  above,
       but with an option (-l) that would be confused with a numactl option.

       numactl  --preferred=1 numactl --show Set preferred node 1 and show the
       resulting state.

       numactl --interleave=all --shmkeyfile /tmp/shmkey Interleave all of the
       sysv shared memory regiion specified by /tmp/shmkey over all nodes.

       numactl  --offset=1G  --length=1G --membind=1 --file /dev/shm/A --touch
       Bind the second gigabyte in the tmpfs file /dev/shm/A to node 1.

       numactl --localalloc /dev/shm/file Reset  the  policy  for  the  shared
       memory file file to the default localalloc policy.

NOTES

       Requires an NUMA policy aware kernel.

       Command  is  not  executed  using  a  shell.  If  you want to use shell
       metacharacters in the child use sh -c as wrapper.

       Setting policy for a hugetlbfs file does currently not work because  it
       cannot be extended by truncate.

       Shared  memory  segments  larger than numactl’s address space cannot be
       completely policied. This could be a problem  on  32bit  architectures.
       Changing it piece by piece may work.

       The  old  --cpubind  which  accepts  node  numbers, not cpu numbers, is
       deprecated and replaced with the new  --cpunodebind  and  --physcpubind
       options.

FILES

       /proc/cpuinfo  for the listing of active CPUs. See proc(5) for details.

       /sys/devices/system/node/node*/numastat for NUMA memory hit statistics.

COPYRIGHT

       Copyright  2002,2004  Andi  Kleen,  SuSE  Labs.   numactl  and the demo
       programs are under the GNU General Public License, v.2

SEE ALSO

       set_mempolicy(2) , get_mempolicy(2) , mbind(2) , sched_setaffinity(2) ,
       sched_getaffinity(2) , proc(5) , ftok(3) , shmat(2) , migratepages(8)