mentat/num_cpus/fn.get.html
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<h1 class='fqn'><span class='in-band'>Function <a href='index.html'>num_cpus</a>::<wbr><a class="fn" href=''>get</a></span><span class='out-of-band'><span id='render-detail'>
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<pre class='rust fn'>pub fn get() -&gt; <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.usize.html">usize</a></pre><div class='docblock'><p>Returns the number of available CPUs of the current system.</p>
<p>This function will get the number of logical cores. Sometimes this is different from the number
of physical cores (See <a href="https://en.wikipedia.org/wiki/Simultaneous_multithreading">Simultaneous multithreading on Wikipedia</a>).</p>
<h1 id="examples" class="section-header"><a href="#examples">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">cpus</span> <span class="op">=</span> <span class="ident">num_cpus</span>::<span class="ident">get</span>();
<span class="kw">if</span> <span class="ident">cpus</span> <span class="op">&gt;</span> <span class="number">1</span> {
<span class="macro">println</span><span class="macro">!</span>(<span class="string">&quot;We are on a multicore system with {} CPUs&quot;</span>, <span class="ident">cpus</span>);
} <span class="kw">else</span> {
<span class="macro">println</span><span class="macro">!</span>(<span class="string">&quot;We are on a single core system&quot;</span>);
}</pre>
<h1 id="note" class="section-header"><a href="#note">Note</a></h1>
<p>This will check <a href="http://www.gnu.org/software/libc/manual/html_node/CPU-Affinity.html">sched affinity</a> on Linux, showing a lower number of CPUs if the current
thread does not have access to all the computer's CPUs.</p>
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