github.com/krum110487/go-htaccess@v0.0.0-20240316004156-60641c8e7598/tests/data/apache_2_2_34/manual/mod/event.html.en (about) 1 <?xml version="1.0" encoding="ISO-8859-1"?> 2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> 3 <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head> 4 <meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type" /> 5 <!-- 6 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX 7 This file is generated from xml source: DO NOT EDIT 8 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX 9 --> 10 <title>event - Apache HTTP Server Version 2.2</title> 11 <link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" /> 12 <link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" /> 13 <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" /> 14 <script src="../style/scripts/prettify.min.js" type="text/javascript"> 15 </script> 16 17 <link href="../images/favicon.ico" rel="shortcut icon" /><link href="http://httpd.apache.org/docs/current/mod/event.html" rel="canonical" /></head> 18 <body> 19 <div id="page-header"> 20 <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> 21 <p class="apache">Apache HTTP Server Version 2.2</p> 22 <img alt="" src="../images/feather.gif" /></div> 23 <div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div> 24 <div id="path"> 25 <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 2.2</a> > <a href="./">Modules</a></div> 26 <div id="page-content"> 27 <div class="retired"><h4>Please note</h4> 28 <p> This document refers to a legacy release (<strong>2.2</strong>) of Apache httpd. The active release (<strong>2.4</strong>) is documented <a href="http://httpd.apache.org/docs/current">here</a>. If you have not already upgraded, please follow <a href="http://httpd.apache.org/docs/current/upgrading.html">this link</a> for more information.</p> 29 <p>You may follow <a href="http://httpd.apache.org/docs/current/mod/event.html">this link</a> to go to the current version of this document.</p></div><div id="preamble"><h1>Apache MPM event</h1> 30 <div class="toplang"> 31 <p><span>Available Languages: </span><a href="../en/mod/event.html" title="English"> en </a></p> 32 </div> 33 <table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>An experimental variant of the standard <code class="module"><a href="../mod/worker.html">worker</a></code> 34 MPM</td></tr> 35 <tr><th><a href="module-dict.html#Status">Status:</a></th><td>MPM</td></tr> 36 <tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>mpm_event_module</td></tr> 37 <tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>event.c</td></tr></table> 38 <h3>Summary</h3> 39 40 <div class="warning"><h3>Warning</h3> 41 <p>This MPM is experimental, so it may or may not work as 42 expected.</p> 43 </div> 44 45 <p>The <code class="module"><a href="../mod/event.html">event</a></code> Multi-Processing Module (MPM) is 46 designed to allow more requests to be served simultaneously by 47 passing off some processing work to supporting threads, freeing up 48 the main threads to work on new requests. It is based on the 49 <code class="module"><a href="../mod/worker.html">worker</a></code> MPM, which implements a hybrid 50 multi-process multi-threaded server. Run-time configuration 51 directives are identical to those provided by 52 <code class="module"><a href="../mod/worker.html">worker</a></code>.</p> 53 54 <p>To use the <code class="module"><a href="../mod/event.html">event</a></code> MPM, add 55 <code>--with-mpm=event</code> to the <code class="program"><a href="../programs/configure.html">configure</a></code> 56 script's arguments when building the <code class="program"><a href="../programs/httpd.html">httpd</a></code>.</p> 57 58 </div> 59 <div id="quickview"><h3>Topics</h3> 60 <ul id="topics"> 61 <li><img alt="" src="../images/down.gif" /> <a href="#how-it-works">How it Works</a></li> 62 <li><img alt="" src="../images/down.gif" /> <a href="#requirements">Requirements</a></li> 63 </ul><h3 class="directives">Directives</h3> 64 <ul id="toc"> 65 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#acceptmutex">AcceptMutex</a></li> 66 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#coredumpdirectory">CoreDumpDirectory</a></li> 67 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#enableexceptionhook">EnableExceptionHook</a></li> 68 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#group">Group</a></li> 69 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#listen">Listen</a></li> 70 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#listenbacklog">ListenBacklog</a></li> 71 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#lockfile">LockFile</a></li> 72 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#maxclients">MaxClients</a></li> 73 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#maxmemfree">MaxMemFree</a></li> 74 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#maxrequestsperchild">MaxRequestsPerChild</a></li> 75 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#maxsparethreads">MaxSpareThreads</a></li> 76 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#minsparethreads">MinSpareThreads</a></li> 77 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#pidfile">PidFile</a></li> 78 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#scoreboardfile">ScoreBoardFile</a></li> 79 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#sendbuffersize">SendBufferSize</a></li> 80 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#serverlimit">ServerLimit</a></li> 81 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#startservers">StartServers</a></li> 82 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#threadlimit">ThreadLimit</a></li> 83 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#threadsperchild">ThreadsPerChild</a></li> 84 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#threadstacksize">ThreadStackSize</a></li> 85 <li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#user">User</a></li> 86 </ul> 87 <h3>See also</h3> 88 <ul class="seealso"> 89 <li><a href="worker.html">The worker MPM</a></li> 90 </ul><ul class="seealso"><li><a href="#comments_section">Comments</a></li></ul></div> 91 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> 92 <div class="section"> 93 <h2><a name="how-it-works" id="how-it-works">How it Works</a></h2> 94 <p>This MPM tries to fix the 'keep alive problem' in HTTP. After a client 95 completes the first request, the client can keep the connection 96 open, and send further requests using the same socket. This can 97 save significant overhead in creating TCP connections. However, 98 Apache traditionally keeps an entire child process/thread waiting 99 for data from the client, which brings its own disadvantages. To 100 solve this problem, this MPM uses a dedicated thread to handle both 101 the Listening sockets, and all sockets that are in a Keep Alive 102 state.</p> 103 104 <p>The MPM assumes that the underlying <code>apr_pollset</code> 105 implementation is reasonably threadsafe. This enables the MPM to 106 avoid excessive high level locking, or having to wake up the listener 107 thread in order to send it a keep-alive socket. This is currently 108 only compatible with KQueue and EPoll.</p> 109 110 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> 111 <div class="section"> 112 <h2><a name="requirements" id="requirements">Requirements</a></h2> 113 <p>This MPM depends on <a class="glossarylink" href="../glossary.html#apr" title="see glossary">APR</a>'s atomic 114 compare-and-swap operations for thread synchronization. If you are 115 compiling for an x86 target and you don't need to support 386s, or 116 you are compiling for a SPARC and you don't need to run on 117 pre-UltraSPARC chips, add 118 <code>--enable-nonportable-atomics=yes</code> to the 119 <code class="program"><a href="../programs/configure.html">configure</a></code> script's arguments. This will cause 120 APR to implement atomic operations using efficient opcodes not 121 available in older CPUs.</p> 122 123 <p>This MPM does not perform well on older platforms which lack good 124 threading, but the requirement for EPoll or KQueue makes this 125 moot.</p> 126 127 <ul> 128 129 <li>To use this MPM on FreeBSD, FreeBSD 5.3 or higher is recommended. 130 However, it is possible to run this MPM on FreeBSD 5.2.1, if you 131 use <code>libkse</code> (see <code>man libmap.conf</code>).</li> 132 133 <li>For NetBSD, at least version 2.0 is recommended.</li> 134 135 <li>For Linux, a 2.6 kernel is recommended. It is also necessary to 136 ensure that your version of <code>glibc</code> has been compiled 137 with support for EPoll.</li> 138 139 </ul> 140 </div> 141 </div> 142 <div class="bottomlang"> 143 <p><span>Available Languages: </span><a href="../en/mod/event.html" title="English"> en </a></p> 144 </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 again 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 Freenode, or sent to our <a href="http://httpd.apache.org/lists.html">mailing lists</a>.</div> 145 <script type="text/javascript"><!--//--><![CDATA[//><!-- 146 var comments_shortname = 'httpd'; 147 var comments_identifier = 'http://httpd.apache.org/docs/2.2/mod/event.html'; 148 (function(w, d) { 149 if (w.location.hostname.toLowerCase() == "httpd.apache.org") { 150 d.write('<div id="comments_thread"><\/div>'); 151 var s = d.createElement('script'); 152 s.type = 'text/javascript'; 153 s.async = true; 154 s.src = 'https://comments.apache.org/show_comments.lua?site=' + comments_shortname + '&page=' + comments_identifier; 155 (d.getElementsByTagName('head')[0] || d.getElementsByTagName('body')[0]).appendChild(s); 156 } 157 else { 158 d.write('<div id="comments_thread">Comments are disabled for this page at the moment.<\/div>'); 159 } 160 })(window, document); 161 //--><!]]></script></div><div id="footer"> 162 <p class="apache">Copyright 2017 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> 163 <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[//><!-- 164 if (typeof(prettyPrint) !== 'undefined') { 165 prettyPrint(); 166 } 167 //--><!]]></script> 168 </body></html>