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pthread_nsg_attach(3)
NAME
  pthread_nsg_attach - Attaches a thread to a NUMA Scheduling Group
  (libpthread library)

SYNOPSIS
  #include <numa.h>

  int pthread_nsg_attach(
	  nsgid_t nsg,
	  pthread_t thread,
	  long flags );

PARAMETERS
  nsg Specifies the NUMA Scheduling Group (NSG) to which the thread will
      belong.

  thread
      Identifies the thread to attach to the NSG.

  flags
      Specifies options (bit mask) that affect the attachment. See
      DESCRIPTION for details.

DESCRIPTION
  The pthread_nsg_attach() function attaches the thread specified by the
  thread argument to a NUMA Scheduling Group (NSG) specified by the nsg
  argument. An NSG is a set of processes and/or threads that will be
  constrained to reside on the same Resource Affinity Domain (RAD). That is,
  the "home RAD" for all of the processes/threads in an NSG will be the same,
  and the entire group will be migrated together, if at all. The thread
  specified by thread will be removed from any NSG of which it might
  currently be a member, before being added to the specified NSG.

  If the specified thread resides on a different RAD, the thread will be
  reassigned to a single RAD. The home RAD for the thread will be selected as
  follows:

    ·  If the specified NSG already has processes/threads attached, the home
       RAD for the specified thread will be the home RAD for that NSG.

    ·  If the specified NSG is empty, the home RAD for the thread will be
       selected based on the setting of the flags argument.

  The following options are defined for the flags argument:

  NSG_INSIST
      The requested attachment and any implied reassignments are mandatory,
      overriding any prior binding of the specified thread. If this option is
      not set, and the thread is bound (RAD_INSIST) to a different RAD such
      that the system cannot honor the request, the request will fail.

  NSG_SMALLMEM
      The thread has small memory requirements, so the system should favor
      (for the home RAD) those RADs with light CPU loads, independent of
      their available memory. This flag applies only when attaching to an
      empty NSG.

  NSG_LARGEMEM
      The thread has large memory requirements, so the system should favor
      (for the home RAD) those RADs with more available memory, independent
      of their CPU loads. This flag only applies when attaching to an empty
      NSG.

  NSG_MIGRATE
      Arrange for the existing memory (stack pages) of a thread that is
      assigned a new home RAD to be migrated to the new RAD. If omitted, only
      newly allocated pages will be allocated on the new home RAD. Existing
      pages will migrate if/when they experience a high rate of remote cache
      misses. Migration will occur only for pages-in-memory objects that have
      inherited the process's default memory allocation policy.

  NSG_WAIT
      Wait for the requested memory migration to be completed. Effectively,
      this flag specifies "migrate now!".

RETURN VALUES
  0	  Success.

  Integer value
	  Failure. In this case, the returned integer indicates the type of
	  error. Possible errors include the following:

	  [EACCES]
	      The caller does not have execute permission required to attach
	      the thread based on the NSG's permissions.

	  [EBUSY]
	      The thread specified by thread is hard attached (RAD_INSIST) to
	      RADs or has memory wired (locked) on its current RAD such that
	      it cannot be migrated to the common RAD selected for the NSG.

	  [EINVAL]
	      The value of the flags argument is invalid.

	  [ENOMEM]
	      NSG_INSIST and NSG_MIGRATE were specified and no RAD can be
	      found with sufficient memory to accommodate the resulting
	      group.

	  [ESRCH]
	      The thread specified by the thread argument does not exist.

ERRORS
  None.

SEE ALSO
  Functions: nsg_attach_pid(3), nsg_get(3), numa_intro(3)

  Files: numa_types(4)

Index for Section 3

Alphabetical listing for P

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