Computer memory that can be accessed by multiple processes

<span class="mw-page-title-main">Shared memory</span>

Shared memory

<p>In <a href="/en/Computer_science" title="Computer science" class="wl">computer science</a>, <b>shared memory</b> is <a href="/en/Random-access_memory" title="Random-access memory" class="wl">memory</a> that may be simultaneously accessed by multiple programs with an intent to provide communication among them or avoid redundant copies. Shared memory is an efficient means of passing data between programs. Depending on context, programs may run on a single processor or on multiple separate processors.</p>

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<div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none" about="#mwt4">Computer memory that can be accessed by multiple processes</div>
<figure class="mw-halign-right wiki-thumb"><a href="/en/File:Shared_memory.svg" class="mw-file-description image media-thumb" data-hash="File:Shared_memory.svg"><img loading="lazy" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Shared_memory.svg/300px-Shared_memory.svg.png" decoding="async" data-file-width="655" data-file-height="282" data-file-type="drawing" height="129" width="300" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Shared_memory.svg/450px-Shared_memory.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Shared_memory.svg/600px-Shared_memory.svg.png 2x" alt="Shared_memory.svg"></a><figcaption>An illustration of a shared memory system of three processors.</figcaption></figure>

<p>Using memory for communication inside a single program, e.g. among its multiple <a href="/en/Thread_(computer_science)" title="Thread (computer science)" class="mw-redirect wl">threads</a>, is also referred to as shared memory.</p>



In computer science, shared memory is memory that may be simultaneously accessed by multiple programs with an intent to provide communication among them or avoid redundant copies. Shared memory is an efficient means of passing data between programs. Depending on context, programs may run on a single processor or on multiple separate processors. Using memory for communication inside a single program, e.g. among its multiple threads, is also referred to as shared memory. 