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diff --git a/docs/en/ranch/1.4/guide/internals/index.html b/docs/en/ranch/1.4/guide/internals/index.html new file mode 100644 index 00000000..e45a609e --- /dev/null +++ b/docs/en/ranch/1.4/guide/internals/index.html @@ -0,0 +1,246 @@ +<!DOCTYPE html> +<html lang="en"> + +<head> + <meta charset="utf-8"> + <meta name="viewport" content="width=device-width, initial-scale=1.0"> + <meta name="description" content=""> + <meta name="author" content="Loïc Hoguin based on a design from (Soft10) Pol Cámara"> + + <meta name="generator" content="Hugo 0.26" /> + + <title>Nine Nines: Internals</title> + + <link href='https://fonts.googleapis.com/css?family=Open+Sans:400,700,400italic' rel='stylesheet' type='text/css'> + <link href="/css/99s.css?r=1" rel="stylesheet"> + + <link rel="shortcut icon" href="/img/ico/favicon.ico"> + <link rel="apple-touch-icon-precomposed" sizes="114x114" href="/img/ico/apple-touch-icon-114.png"> + <link rel="apple-touch-icon-precomposed" sizes="72x72" href="/img/ico/apple-touch-icon-72.png"> + <link rel="apple-touch-icon-precomposed" href="/img/ico/apple-touch-icon-57.png"> + + +</head> + + +<body class=""> + <header id="page-head"> + <div id="topbar" class="container"> + <div class="row"> + <div class="span2"> + <h1 id="logo"><a href="/" title="99s">99s</a></h1> + </div> + <div class="span10"> + + <div id="side-header"> + <nav> + <ul> + <li><a title="Hear my thoughts" href="/articles">Articles</a></li> + <li><a title="Watch my talks" href="/talks">Talks</a></li> + <li class="active"><a title="Read the docs" href="/docs">Documentation</a></li> + <li><a title="Request my services" href="/services">Consulting & Training</a></li> + </ul> + </nav> + <ul id="social"> + <li> + <a href="https://github.com/ninenines" title="Check my Github repositories"><img src="/img/ico_github.png" data-hover="/img/ico_github_alt.png" alt="Github"></a> + </li> + <li> + <a title="Keep in touch!" href="http://twitter.com/lhoguin"><img src="/img/ico_microblog.png" data-hover="/img/ico_microblog_alt.png"></a> + </li> + <li> + <a title="Contact me" href="mailto:[email protected]"><img src="/img/ico_mail.png" data-hover="/img/ico_mail_alt.png"></a> + </li> + </ul> + </div> + </div> + </div> + </div> + + +</header> + +<div id="contents" class="two_col"> +<div class="container"> +<div class="row"> +<div id="docs" class="span9 maincol"> + +<h1 class="lined-header"><span>Internals</span></h1> + +<div class="paragraph"><p>This chapter may not apply to embedded Ranch as embedding allows you +to use an architecture specific to your application, which may or may +not be compatible with the description of the Ranch application.</p></div> +<div class="paragraph"><p>Note that for everything related to efficiency and performance, +you should perform the benchmarks yourself to get the numbers that +matter to you. Generic benchmarks found on the web may or may not +be of use to you, you can never know until you benchmark your own +system.</p></div> +<div class="sect1"> +<h2 id="_architecture">Architecture</h2> +<div class="sectionbody"> +<div class="paragraph"><p>Ranch is an OTP application.</p></div> +<div class="paragraph"><p>Like all OTP applications, Ranch has a top supervisor. It is responsible +for supervising the <code>ranch_server</code> process and all the listeners that +will be started.</p></div> +<div class="paragraph"><p>The <code>ranch_server</code> gen_server is a central process keeping track of the +listeners and their acceptors. It does so through the use of a public ets +table called <code>ranch_server</code>. The table is owned by the top supervisor +to improve fault tolerance. This way if the <code>ranch_server</code> gen_server +fails, it doesn’t lose any information and the restarted process can +continue as if nothing happened.</p></div> +<div class="paragraph"><p>Ranch uses a custom supervisor for managing connections. This supervisor +keeps track of the number of connections and handles connection limits +directly. While it is heavily optimized to perform the task of creating +connection processes for accepted connections, it is still following the +OTP principles and the usual <code>sys</code> and <code>supervisor</code> calls will work on +it as expected.</p></div> +<div class="paragraph"><p>Listeners are grouped into the <code>ranch_listener_sup</code> supervisor and +consist of three kinds of processes: the listener gen_server, the +acceptor processes and the connection processes, both grouped under +their own supervisor. All of these processes are registered to the +<code>ranch_server</code> gen_server with varying amount of information.</p></div> +<div class="paragraph"><p>All socket operations, including listening for connections, go through +transport handlers. Accepted connections are given to the protocol handler. +Transport handlers are simple callback modules for performing operations on +sockets. Protocol handlers start a new process, which receives socket +ownership, with no requirements on how the code should be written inside +that new process.</p></div> +</div> +</div> +<div class="sect1"> +<h2 id="_number_of_acceptors">Number of acceptors</h2> +<div class="sectionbody"> +<div class="paragraph"><p>The second argument to <code>ranch:start_listener/5</code> is the number of +processes that will be accepting connections. Care should be taken +when choosing this number.</p></div> +<div class="paragraph"><p>First of all, it should not be confused with the maximum number +of connections. Acceptor processes are only used for accepting and +have nothing else in common with connection processes. Therefore +there is nothing to be gained from setting this number too high, +in fact it can slow everything else down.</p></div> +<div class="paragraph"><p>Second, this number should be high enough to allow Ranch to accept +connections concurrently. But the number of cores available doesn’t +seem to be the only factor for choosing this number, as we can +observe faster accepts if we have more acceptors than cores. It +might be entirely dependent on the protocol, however.</p></div> +<div class="paragraph"><p>Our observations suggest that using 100 acceptors on modern hardware +is a good solution, as it’s big enough to always have acceptors ready +and it’s low enough that it doesn’t have a negative impact on the +system’s performances.</p></div> +</div> +</div> +<div class="sect1"> +<h2 id="_platform_specific_tcp_features">Platform-specific TCP features</h2> +<div class="sectionbody"> +<div class="paragraph"><p>Some socket options are platform-specific and not supported by <code>inet</code>. +They can be of interest because they generally are related to +optimizations provided by the underlying OS. They can still be enabled +thanks to the <code>raw</code> option, for which we will see an example.</p></div> +<div class="paragraph"><p>One of these features is <code>TCP_DEFER_ACCEPT</code> on Linux. It is a simplified +accept mechanism which will wait for application data to come in before +handing out the connection to the Erlang process.</p></div> +<div class="paragraph"><p>This is especially useful if you expect many connections to be mostly +idle, perhaps part of a connection pool. They can be handled by the +kernel directly until they send any real data, instead of allocating +resources to idle connections.</p></div> +<div class="paragraph"><p>To enable this mechanism, the following option can be used.</p></div> +<div class="listingblock"> +<div class="title">Using raw transport options</div> +<div class="content"><!-- Generator: GNU source-highlight 3.1.8 +by Lorenzo Bettini +http://www.lorenzobettini.it +http://www.gnu.org/software/src-highlite --> +<pre><tt>{<span style="color: #FF6600">raw</span>, <span style="color: #993399">6</span>, <span style="color: #993399">9</span>, <span style="color: #990000"><<</span> <span style="font-weight: bold"><span style="color: #000000">30:32</span></span><span style="color: #990000">/</span><span style="color: #FF6600">native</span> <span style="color: #990000">>></span>}</tt></pre></div></div> +<div class="paragraph"><p>It means go on layer 6, turn on option 9 with the given integer parameter.</p></div> +</div> +</div> + + + + + + + + + + + <nav style="margin:1em 0"> + + <a style="float:left" href="https://ninenines.eu/docs/en/ranch/1.4/guide/ssl_auth/"> + SSL client authentication + </a> + + + + </nav> + + + + +</div> + +<div class="span3 sidecol"> + + +<h3> + Ranch + 1.4 + + User Guide +</h3> + +<ul> + + <li><a href="/docs/en/ranch/1.4/guide">User Guide</a></li> + + + <li><a href="/docs/en/ranch/1.4/manual">Function Reference</a></li> + + +</ul> + +<h4 id="docs-nav">Navigation</h4> + +<h4>Version select</h4> +<ul> + + + + <li><a href="/docs/en/ranch/1.4/guide">1.4</a></li> + + <li><a href="/docs/en/ranch/1.3/guide">1.3</a></li> + + <li><a href="/docs/en/ranch/1.2/guide">1.2</a></li> + +</ul> + +</div> +</div> +</div> +</div> + + <footer> + <div class="container"> + <div class="row"> + <div class="span6"> + <p id="scroll-top"><a href="#">↑ Scroll to top</a></p> + <nav> + <ul> + <li><a href="mailto:[email protected]" title="Contact us">Contact us</a></li><li><a href="https://github.com/ninenines/ninenines.github.io" title="Github repository">Contribute to this site</a></li> + </ul> + </nav> + </div> + <div class="span6 credits"> + <p><img src="/img/footer_logo.png"></p> + <p>Copyright © Loïc Hoguin 2012-2016</p> + </div> + </div> + </div> + </footer> + + + <script src="/js/custom.js"></script> + </body> +</html> + + |