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lgrp_init(3lgrp) [linux man page]

lgrp_init(3LGRP)														  lgrp_init(3LGRP)

NAME

       lgrp_init - initialize lgroup interface

SYNOPSIS

       cc [ flag... ] file... -llgrp [ library... ]
       #include <sys/lgrp_user.h>

       lgrp_cookie_t lgrp_init(lgrp_view_t view);

       The  lgrp_init()  function initializes the lgroup interface and takes a snapshot of the lgroup hierarchy with the given view.  If the given
       view is LGRP_VIEW_CALLER, the snapshot contains only the resources that are available to the caller (for example, with respect to processor
       sets). When the view is LGRP_VIEW_OS, the snapshot contains what is available to the operating system.

       Given the view, lgrp_init() returns a cookie representing this snapshot of the lgroup hierarchy. This cookie should be used with other rou-
       tines in the lgroup interface needing the lgroup hierarchy. The lgrp_fini(3LGRP) function should be called with the cookie when	it  is	no
       longer needed.

       The  lgroup  hiearchy represents the latency topology of the machine.  The hierarchy is simplified to be a tree and can be used to find the
       nearest resources.

       The lgroup hiearchy consists of a root lgroup, which is the maximum  bounding locality group of the system, contains all the CPU and memory
       resources  of  the machine, and may contain  other locality groups that contain CPUs and memory within a smaller locality. The leaf lgroups
       contain resources within the smallest latency.

       The resources of a given lgroup come directly from the lgroup itself or from  leaf  lgroups  contained  within  the  lgroup.  Leaf  lgroups
       directly contain their own resources and do not encapsulate any other lgroups.

       The  lgroup  hierarchy  can  be	used  to find the nearest resources. From a given lgroup, the closest resources can be found in the lgroup
       itself. After that, the next nearest resources can be found in its parent lgroup, and so on until the root lgroup is reached where all  the
       resources of the machine are located.

       Upon successful completion, lgrp_init() returns a cookie. Otherwise it returns LGRP_COOKIE_NONE and sets errno to indicate the error.

       The lgrp_init() function will fail if:

       EINVAL	       The view is not valid.

       ENOMEM	       There was not enough memory to allocate the snapshot of the lgroup hierarchy.

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Evolving			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

       lgrp_children(3LGRP),  lgrp_cookie_stale(3LGRP),  lgrp_cpus(3LGRP),  lgrp_fini(3LGRP),  lgrp_mem_size(3LGRP), lgrp_nlgrps(3LGRP), lgrp_par-
       ents(3LGRP), lgrp_resources(3LGRP), lgrp_root(3LGRP), lgrp_view(3LGRP), liblgrp(3LIB), attributes(5)

								    26 Jan 2005 						  lgrp_init(3LGRP)

Check Out this Related Man Page

lgrp_resources(3LGRP)													     lgrp_resources(3LGRP)

NAME

       lgrp_resources - get lgroup resources of given lgroup

SYNOPSIS

       cc [ flag ... ] file... -llgrp [ library ... ]
       #include <sys/lgrp_user.h>

       int lgrp_resources(lgrp_cookie_t cookie, lgrp_id_t lgrp, lgrp_id_t *lgrpids, uint_t count, lgrp_rsrc_t type);

       The  lgrp_resources() function takes a  cookie  representing  a snapshot of the lgroup hierarchy obtained from lgrp_init(3LGRP) and returns
       the number of resources in the lgroup specified by lgrp.  The resources are represented by a set of lgroups in which each  lgroup  directly
       contains CPU and/or memory resources.

       The type argument should be set to one of the following values to specify whether the CPU or memory resources should be returned:

       LGRP_RSRC_CPU	  /* CPU resources */
       LGRP_RSRC_MEM	  /* Memory resources */

       If  the	lgrpids[] argument is non-null and the count argument is non-zero, lgrp_resources() stores up to the specified count of lgroup IDs
       into the lgrpids[] array.

       Upon  successful  completion,  lgrp_resources() returns the number  of lgroup resources. Otherwise, -1 is returned  and	errno  is  set	to
       indicate the error.

       The lgrp_resources() function will fail if:

       EINVAL	       The specified cookie, lgroup  ID, or type is not valid.

       ESRCH	       The specified lgroup ID was not found.

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Evolving			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

       lgrp_children(3LGRP), lgrp_init(3LGRP), lgrp_parents(3LGRP), liblgrp(3LIB), attributes(5)

								    26 Jan 2005 					     lgrp_resources(3LGRP)
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