pthread_nsg_attach(3)					     Library Functions Manual					     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

       Specifies  the NUMA Scheduling Group (NSG) to which the thread will belong.  Identifies the thread to attach to the NSG.  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 speci-
       fied 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: 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.	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.  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.  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. Exist-
       ing  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.  Wait for the requested memory migration to be completed.  Effectively,
       this flag specifies "migrate now!".

RETURN VALUES

       Success.   Failure.  In this case, the returned integer indicates the type of error. Possible errors include the following: The caller does
       not have execute permission required to attach the thread based on the NSG's permissions.  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.  The value of the flags argument is invalid.  NSG_INSIST and NSG_MIGRATE were specified and no RAD can be found with sufficient memory
       to accommodate the resulting group.  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)

															     pthread_nsg_attach(3)