Linux and UNIX Man Pages

Linux & Unix Commands - Search Man Pages

lgrp_init(3lgrp) [php 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_cookie_stale(3LGRP)				 Locality Group Library Functions				  lgrp_cookie_stale(3LGRP)

NAME
lgrp_cookie_stale - determine whether snapshot of lgroup hierarchy is stale SYNOPSIS
cc [ flag ... ] file... -llgrp [ library ... ] #include <sys/lgrp_user.h> int lgrp_cookie_stale(lgrp_cookie_t cookie); DESCRIPTION
The lgrp_cookie_stale() function takes a cookie representing the snapshot of the lgroup hierarchy obtained from lgrp_init(3LGRP) and returns whether it is stale. The snapshot can become out-of-date for a number of reasons depending on its view. If the snapshot was taken with LGRP_VIEW_OS, changes in the lgroup hierarchy from dynamic reconfiguration, CPU on/offline, or other conditions can cause the snapshot to become out-of-date. A snapshot taken with LGRP_VIEW_CALLER can be affected by the caller's processor set binding and changes in its processor set itself, as well as changes in the lgroup hierarchy. If the snapshot needs to be updated, lgrp_fini(3LGRP) should be called with the old cookie and lgrp_init() should be called to obtain a new snapshot. RETURN VALUES
Upon successful completion, lgrp_cookie_stale() returns whether the cookie is stale. Otherwise, it returns -1 and sets errno to indicate the error. ERRORS
The lgrp_cookie_stale() function will fail if: EINVAL The cookie is not valid. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Evolving | +-----------------------------+-----------------------------+ |MT-Level |MT-Safe | +-----------------------------+-----------------------------+ SEE ALSO
lgrp_init(3LGRP), lgrp_fini(3LGRP), lgrp_view(3LGRP), liblgrp(3LIB), attributes(5) SunOS 5.10 16 Apr 2003 lgrp_cookie_stale(3LGRP)
Man Page