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diff --git a/docs/manual/mpm.html.en b/docs/manual/mpm.html.en new file mode 100644 index 0000000..2844e10 --- /dev/null +++ b/docs/manual/mpm.html.en @@ -0,0 +1,211 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head> +<meta content="text/html; charset=UTF-8" http-equiv="Content-Type" /> +<!-- + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + This file is generated from xml source: DO NOT EDIT + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + --> +<title>Multi-Processing Modules (MPMs) - Apache HTTP Server Version 2.4</title> +<link href="./style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" /> +<link href="./style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" /> +<link href="./style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /><link rel="stylesheet" type="text/css" href="./style/css/prettify.css" /> +<script src="./style/scripts/prettify.min.js" type="text/javascript"> +</script> + +<link href="./images/favicon.ico" rel="shortcut icon" /></head> +<body id="manual-page"><div id="page-header"> +<p class="menu"><a href="./mod/">Modules</a> | <a href="./mod/directives.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="./glossary.html">Glossary</a> | <a href="./sitemap.html">Sitemap</a></p> +<p class="apache">Apache HTTP Server Version 2.4</p> +<img alt="" src="./images/feather.png" /></div> +<div class="up"><a href="./"><img title="<-" alt="<-" src="./images/left.gif" /></a></div> +<div id="path"> +<a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="./">Version 2.4</a></div><div id="page-content"><div id="preamble"><h1>Multi-Processing Modules (MPMs)</h1> +<div class="toplang"> +<p><span>Available Languages: </span><a href="./de/mpm.html" hreflang="de" rel="alternate" title="Deutsch"> de </a> | +<a href="./en/mpm.html" title="English"> en </a> | +<a href="./es/mpm.html" hreflang="es" rel="alternate" title="Español"> es </a> | +<a href="./fr/mpm.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | +<a href="./ja/mpm.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | +<a href="./ko/mpm.html" hreflang="ko" rel="alternate" title="Korean"> ko </a> | +<a href="./tr/mpm.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a> | +<a href="./zh-cn/mpm.html" hreflang="zh-cn" rel="alternate" title="Simplified Chinese"> zh-cn </a></p> +</div> + +<p>This document describes what a Multi-Processing Module is and +how they are used by the Apache HTTP Server.</p> +</div> +<div id="quickview"><a href="https://www.apache.org/foundation/contributing.html" class="badge"><img src="https://www.apache.org/images/SupportApache-small.png" alt="Support Apache!" /></a><ul id="toc"><li><img alt="" src="./images/down.gif" /> <a href="#introduction">Introduction</a></li> +<li><img alt="" src="./images/down.gif" /> <a href="#defaults">MPM Defaults</a></li> +<li><img alt="" src="./images/down.gif" /> <a href="#static">Building an MPM as a static module</a></li> +<li><img alt="" src="./images/down.gif" /> <a href="#dynamic">Building an MPM as a DSO module</a></li> +</ul><h3>See also</h3><ul class="seealso"><li><a href="#comments_section">Comments</a></li></ul></div> +<div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> +<div class="section"> +<h2><a name="introduction" id="introduction">Introduction</a></h2> + + <p>The Apache HTTP Server is designed to be a powerful and + flexible web server that can work on a very wide variety of + platforms in a range of different environments. Different + platforms and different environments often require different + features, or may have different ways of implementing the same + feature most efficiently. Apache httpd has always accommodated a wide + variety of environments through its modular design. This design + allows the webmaster to choose which features will be included + in the server by selecting which modules to load either at + compile-time or at run-time.</p> + + <p>Apache HTTP Server 2.0 extends this modular design to the most basic + functions of a web server. The server ships with a selection of + Multi-Processing Modules (MPMs) which are responsible for + binding to network ports on the machine, accepting requests, + and dispatching children to handle the requests.</p> + + <p>Extending the modular design to this level of the server + allows two important benefits:</p> + + <ul> + <li>Apache httpd can more cleanly and efficiently support a wide + variety of operating systems. In particular, the Windows + version of the server is now much more efficient, since + <code class="module"><a href="./mod/mpm_winnt.html">mpm_winnt</a></code> can use native + networking features in place of the POSIX layer used in + Apache httpd 1.3. This benefit also extends to other operating + systems that implement specialized MPMs.</li> + + <li>The server can be better customized for the needs of the + particular site. For example, sites that need a great deal of + scalability can choose to use a threaded MPM like + <code class="module"><a href="./mod/worker.html">worker</a></code> or <code class="module"><a href="./mod/event.html">event</a></code>, while sites requiring + stability or compatibility with older software can use a + <code class="module"><a href="./mod/prefork.html">prefork</a></code>.</li> + </ul> + + <p>At the user level, MPMs appear much like other Apache httpd + modules. The main difference is that one and only one MPM must + be loaded into the server at any time. The list of available + MPMs appears on the <a href="mod/">module index page</a>.</p> + +</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> +<div class="section"> +<h2><a name="defaults" id="defaults">MPM Defaults</a></h2> + +<p>The following table lists the default MPMs for various operating +systems. This will be the MPM selected if you do not make another +choice at compile-time.</p> + +<table class="bordered"><tr><td>Netware</td><td><code class="module"><a href="./mod/mpm_netware.html">mpm_netware</a></code></td></tr> +<tr class="odd"><td>OS/2</td><td><code class="module"><a href="./mod/mpmt_os2.html">mpmt_os2</a></code></td></tr> +<tr><td>Unix</td><td><code class="module"><a href="./mod/prefork.html">prefork</a></code>, <code class="module"><a href="./mod/worker.html">worker</a></code>, or + <code class="module"><a href="./mod/event.html">event</a></code>, depending on platform capabilities</td></tr> +<tr class="odd"><td>Windows</td><td><code class="module"><a href="./mod/mpm_winnt.html">mpm_winnt</a></code></td></tr> +</table> + +<div class="note"><p>Here, 'Unix' is used to mean Unix-like operating systems, such as +Linux, BSD, Solaris, Mac OS X, etc.</p></div> + +<p>In the case of Unix, the decision as to which MPM is installed is +based on two questions:</p> +<p>1. Does the system support threads?</p> +<p>2. Does the system support thread-safe polling (Specifically, the +kqueue and epoll functions)?</p> + +<p>If the answer to both questions is 'yes', the default MPM is +<code class="module"><a href="./mod/event.html">event</a></code>.</p> + +<p>If The answer to #1 is 'yes', but the answer to #2 is 'no', the +default will be <code class="module"><a href="./mod/worker.html">worker</a></code>.</p> + +<p>If the answer to both questions is 'no', then the default MPM will be +<code class="module"><a href="./mod/prefork.html">prefork</a></code>.</p> + +<p>In practical terms, this means that the default will almost always be +<code class="module"><a href="./mod/event.html">event</a></code>, as all modern operating systems support these +two features.</p> + +</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> +<div class="section"> +<h2><a name="static" id="static">Building an MPM as a static module</a></h2> + + <p>MPMs can be built as static modules on all platforms. A single MPM + is chosen at build time and linked into the server. The server must + be rebuilt in order to change the MPM.</p> + + <p>To override the default MPM choice, use the + <code>--with-mpm=<em>NAME</em></code> option of the + <code class="program"><a href="./programs/configure.html">configure</a></code> script. <em>NAME</em> is the name of the + desired MPM.</p> + + <p>Once the server has been compiled, it is possible to determine which MPM + was chosen by using <code>./httpd -l</code>. This command will list every + module that is compiled into the server, including the MPM.</p> + +</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> +<div class="section"> +<h2><a name="dynamic" id="dynamic">Building an MPM as a DSO module</a></h2> + + <p>On Unix and similar platforms, MPMs can be built as DSO modules and + dynamically loaded into the server in the same manner as other DSO + modules. Building MPMs as DSO modules allows the MPM to be changed by + updating the <code class="directive"><a href="./mod/mod_so.html#loadmodule">LoadModule</a></code> directive + for the MPM instead of by rebuilding the server.</p> + + <pre class="prettyprint lang-config">LoadModule mpm_prefork_module modules/mod_mpm_prefork.so</pre> + + + <p>Attempting to <code class="directive"><a href="./mod/mod_so.html#loadmodule">LoadModule</a></code> + more than one MPM will result in a startup failure with the + following error.</p> + + <div class="example"><p><code>AH00534: httpd: Configuration error: More than one MPM + loaded.</code></p></div> + + <p>This feature is enabled using the + <code>--enable-mpms-shared</code> option of the <code class="program"><a href="./programs/configure.html">configure</a></code> + script. + With argument <code><em>all</em></code>, all possible MPMs for the platform + will be installed. Alternately, a list of MPMs can be specified as the + argument.</p> + + <p>The default MPM, either selected automatically or specified with the + <code>--with-mpm</code> option of the <code class="program"><a href="./programs/configure.html">configure</a></code> + script, will be loaded in the generated server configuration file. Edit the + <code class="directive"><a href="./mod/mod_so.html#loadmodule">LoadModule</a></code> directive to select a + different MPM.</p> + +</div></div> +<div class="bottomlang"> +<p><span>Available Languages: </span><a href="./de/mpm.html" hreflang="de" rel="alternate" title="Deutsch"> de </a> | +<a href="./en/mpm.html" title="English"> en </a> | +<a href="./es/mpm.html" hreflang="es" rel="alternate" title="Español"> es </a> | +<a href="./fr/mpm.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | +<a href="./ja/mpm.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | +<a href="./ko/mpm.html" hreflang="ko" rel="alternate" title="Korean"> ko </a> | +<a href="./tr/mpm.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a> | +<a href="./zh-cn/mpm.html" hreflang="zh-cn" rel="alternate" title="Simplified Chinese"> zh-cn </a></p> +</div><div class="top"><a href="#page-header"><img src="./images/up.gif" alt="top" /></a></div><div class="section"><h2><a id="comments_section" name="comments_section">Comments</a></h2><div class="warning"><strong>Notice:</strong><br />This is not a Q&A section. Comments placed here should be pointed towards suggestions on improving the documentation or server, and may be removed by our moderators if they are either implemented or considered invalid/off-topic. Questions on how to manage the Apache HTTP Server should be directed at either our IRC channel, #httpd, on Libera.chat, or sent to our <a href="https://httpd.apache.org/lists.html">mailing lists</a>.</div> +<script type="text/javascript"><!--//--><![CDATA[//><!-- +var comments_shortname = 'httpd'; +var comments_identifier = 'http://httpd.apache.org/docs/2.4/mpm.html'; +(function(w, d) { + if (w.location.hostname.toLowerCase() == "httpd.apache.org") { + d.write('<div id="comments_thread"><\/div>'); + var s = d.createElement('script'); + s.type = 'text/javascript'; + s.async = true; + s.src = 'https://comments.apache.org/show_comments.lua?site=' + comments_shortname + '&page=' + comments_identifier; + (d.getElementsByTagName('head')[0] || d.getElementsByTagName('body')[0]).appendChild(s); + } + else { + d.write('<div id="comments_thread">Comments are disabled for this page at the moment.<\/div>'); + } +})(window, document); +//--><!]]></script></div><div id="footer"> +<p class="apache">Copyright 2023 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p> +<p class="menu"><a href="./mod/">Modules</a> | <a href="./mod/directives.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="./glossary.html">Glossary</a> | <a href="./sitemap.html">Sitemap</a></p></div><script type="text/javascript"><!--//--><![CDATA[//><!-- +if (typeof(prettyPrint) !== 'undefined') { + prettyPrint(); +} +//--><!]]></script> +</body></html>
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