Provided by: numactl_2.0.11-2.2_amd64 bug

NAME

       numactl - Control NUMA policy for processes or shared memory

SYNOPSIS

       numactl  [  --all  ]  [  --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.

       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. When same is specified the previous nodemask specified  on  the
       command line is used.  all means all nodes in the current cpuset.

       Instead of a number a node can also be:

       netdev:DEV                 The node connected to network device DEV.
       file:PATH                  The node the block device of PATH.
       ip:HOST                    The node of the network device of HOST
       block:PATH                 The node of block device PATH
       pci:[seg:]bus:dev[:func]   The node of a PCI device.

       Note  that  block  resolves  the kernel block device names only for udev names in /dev use
       file:

       Policy settings are:

       --all, -a
              Unset default cpuset awareness,  so  user  can  use  all  possible  CPUs/nodes  for
              following policy settings.

       --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.

       --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 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, --preferred, --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  --cpunodebind=0 --membind=0,1 process Run process on node 0 with memory allocated
       on node 0 and 1.

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

       numactl  --cpunodebind=netdev:eth0 --membind=netdev:eth0 network-server Run network-server
       on the node of network device eth0 with its memory also in the same node.

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

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

       Place a tmpfs file on 2 nodes:
         numactl --membind=2 dd if=/dev/zero of=/dev/shm/A bs=1M count=1024
         numactl --membind=3 dd if=/dev/zero of=/dev/shm/A seek=1024 bs=1M count=1024

       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)