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diff --git a/static/freebsd/man4/numa.4 3.html b/static/freebsd/man4/numa.4 3.html new file mode 100644 index 00000000..0dbba782 --- /dev/null +++ b/static/freebsd/man4/numa.4 3.html @@ -0,0 +1,121 @@ +<table class="head"> + <tr> + <td class="head-ltitle">NUMA(4)</td> + <td class="head-vol">Device Drivers Manual</td> + <td class="head-rtitle">NUMA(4)</td> + </tr> +</table> +<div class="manual-text"> +<section class="Sh"> +<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> +<p class="Pp"><code class="Nm">NUMA</code> — <span class="Nd">Non-Uniform + Memory Access</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<p class="Pp"><code class="Cd">options MAXMEMDOM</code> + <br/> + <code class="Cd">options NUMA</code></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">Non-Uniform Memory Access is a computer architecture design which + involves unequal costs between processors, memory and IO devices in a given + system.</p> +<p class="Pp">In a <code class="Nm">NUMA</code> architecture, the latency to + access specific memory or IO devices depends upon which processor the memory + or device is attached to. Accessing memory local to a processor is faster + than accessing memory that is connected to one of the other processors. + <span class="Ux">FreeBSD</span> implements NUMA-aware memory allocation + policies. By default it attempts to ensure that allocations are balanced + across each domain. Users may override the default domain selection policy + using <a class="Xr">cpuset(1)</a>.</p> +<p class="Pp"><code class="Nm">NUMA</code> support is enabled when the + <code class="Cd">NUMA</code> option is specified in the kernel configuration + file. Each platform defines the <code class="Cd">MAXMEMDOM</code> constant, + which specifies the maximum number of supported NUMA domains. This constant + may be specified in the kernel configuration file. + <code class="Nm">NUMA</code> support can be disabled at boot time by setting + the <var class="Va">vm.numa.disabled</var> tunable to 1. Other values for + this tunable are currently ignored.</p> +<p class="Pp">Thread and process <code class="Nm">NUMA</code> policies are + controlled with the <a class="Xr">cpuset_getdomain(2)</a> and + <a class="Xr">cpuset_setdomain(2)</a> syscalls. The + <a class="Xr">cpuset(1)</a> tool is available for starting processes with a + non-default policy, or to change the policy of an existing thread or + process. See <a class="Xr">SMP(4)</a> for information about CPU to domain + mapping.</p> +<p class="Pp">Systems with non-uniform access to I/O devices may mark those + devices with the local VM domain identifier. Drivers can find out their + local domain information by calling <a class="Xr">bus_get_domain(9)</a>.</p> +<section class="Ss"> +<h2 class="Ss" id="MIB_Variables"><a class="permalink" href="#MIB_Variables">MIB + Variables</a></h2> +<p class="Pp">The operation of <code class="Nm">NUMA</code> is controlled and + exposes information with these <a class="Xr">sysctl(8)</a> MIB + variables:</p> +<p class="Pp"></p> +<dl class="Bl-tag Bl-compact"> + <dt id="vm.ndomains"><var class="Va">vm.ndomains</var></dt> + <dd>The number of VM domains which have been detected. + <p class="Pp"></p> + </dd> + <dt id="vm.phys_locality"><var class="Va">vm.phys_locality</var></dt> + <dd>A table indicating the relative cost of each VM domain to each other. A + value of 10 indicates equal cost. A value of -1 means the locality map is + not available or no locality information is available. + <p class="Pp"></p> + </dd> + <dt id="vm.phys_segs"><var class="Va">vm.phys_segs</var></dt> + <dd>The map of physical memory, grouped by VM domain.</dd> +</dl> +</section> +</section> +<section class="Sh"> +<h1 class="Sh" id="IMPLEMENTATION_NOTES"><a class="permalink" href="#IMPLEMENTATION_NOTES">IMPLEMENTATION + NOTES</a></h1> +<p class="Pp">The current <code class="Nm">NUMA</code> implementation is + VM-focused. The hardware <code class="Nm">NUMA</code> domains are mapped + into a contiguous, non-sparse VM domain space, starting from 0. Thus, VM + domain information (for example, the domain identifier) is not necessarily + the same as is found in the hardware specific information. Policy + information is available in both struct thread and struct proc.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE + ALSO</a></h1> +<p class="Pp"><a class="Xr">cpuset(1)</a>, + <a class="Xr">cpuset_getaffinity(2)</a>, + <a class="Xr">cpuset_setaffinity(2)</a>, <a class="Xr">SMP(4)</a>, + <a class="Xr">bus_get_domain(9)</a></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> +<p class="Pp"><code class="Nm">NUMA</code> first appeared in + <span class="Ux">FreeBSD 9.0</span> as a first-touch allocation policy with + a fail-over to round-robin allocation and was not configurable. It was then + modified in <span class="Ux">FreeBSD 10.0</span> to implement a round-robin + allocation policy and was also not configurable.</p> +<p class="Pp">The <a class="Xr">numa_getaffinity(2)</a> and + <a class="Xr">numa_setaffinity(2)</a> syscalls and the + <a class="Xr">numactl(1)</a> tool first appeared in <span class="Ux">FreeBSD + 11.0</span> and were removed in <span class="Ux">FreeBSD 12.0</span>. The + current implementation appeared in <span class="Ux">FreeBSD 12.0</span>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1> +<p class="Pp">This manual page written by <span class="An">Adrian Chadd</span> + <<a class="Mt" href="mailto:adrian@FreeBSD.org">adrian@FreeBSD.org</a>>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="NOTES"><a class="permalink" href="#NOTES">NOTES</a></h1> +<p class="Pp">No statistics are kept to indicate how often + <code class="Nm">NUMA</code> allocation policies succeed or fail.</p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">October 22, 2018</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |