1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
<?xml version="1.0" encoding="ISO-8859-1"?>
<!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><!--
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
This file is generated from xml source: DO NOT EDIT
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
-->
<title>Multi-Processing Modules (MPMs) - Apache HTTP Server</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 href="./images/favicon.ico" rel="shortcut icon" /><link href="http://httpd.apache.org/docs/2.2/mpm.html" rel="canonical" /></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="./faq/">FAQ</a> | <a href="./glossary.html">Glossary</a> | <a href="./sitemap.html">Sitemap</a></p>
<p class="apache">Apache HTTP Server Version 2.0</p>
<img alt="" src="./images/feather.gif" /></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 2.0</a></div><div style="width: 90%;" class="outofdate"><h4>Please note</h4>
This document refers to the 2.0 version of Apache httpd, which is no longer recommended.<br />
If you are using the current versions of httpd (2.2 or 2.4), please visit their documentations instead:<br /><ul><li><a href="http://httpd.apache.org/docs/2.2/">Apache HTTP Server 2.2 documentation</a></li><li><a href="http://httpd.apache.org/docs/2.4/">Apache HTTP Server 2.4 documentation</a></li></ul>
You may follow <a href="http://httpd.apache.org/docs/2.2/mpm.html">this link</a> to
go to the 2.2 version of this document.
</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="./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="./ru/mpm.html" hreflang="ru" rel="alternate" title="Russian"> ru </a> |
<a href="./tr/mpm.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </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"><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="#choosing">Choosing an MPM</a></li>
<li><img alt="" src="./images/down.gif" /> <a href="#defaults">MPM Defaults</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 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 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 can more cleanly and efficiently support a wide
variety of operating systems. In particular, the Windows
version of Apache 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 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>, while sites requiring
stability or compatibility with older software can use a
<code class="module"><a href="./mod/prefork.html">prefork</a></code>. In addition,
special features like serving different hosts under different
userids (<code class="module"><a href="./mod/perchild.html">perchild</a></code>) can be
provided.</li>
</ul>
<p>At the user level, MPMs appear much like other Apache
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="choosing" id="choosing">Choosing an MPM</a></h2>
<p>MPMs must be chosen during configuration, and compiled into
the server. Compilers are capable of optimizing a lot of
functions if threads are used, but only if they know that
threads are being used.</p>
<p>To actually choose the desired MPM, use the argument
<code>--with-mpm=<em>NAME</em></code> with 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="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>
<tr><td>BeOS</td><td><code class="module"><a href="./mod/beos.html">beos</a></code></td></tr>
<tr><td>Netware</td><td><code class="module"><a href="./mod/mpm_netware.html">mpm_netware</a></code></td></tr>
<tr><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></td></tr>
<tr><td>Windows</td><td><code class="module"><a href="./mod/mpm_winnt.html">mpm_winnt</a></code></td></tr>
</table>
</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="./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="./ru/mpm.html" hreflang="ru" rel="alternate" title="Russian"> ru </a> |
<a href="./tr/mpm.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p>
</div><div id="footer">
<p class="apache">Copyright 2011 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="./faq/">FAQ</a> | <a href="./glossary.html">Glossary</a> | <a href="./sitemap.html">Sitemap</a></p></div>
</body></html>
|
