📄 worker.html.en
字号:
<?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>worker - 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" /></head><body><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-project/">Documentation</a> > <a href="../">Version 2.0</a> > <a href="./">Modules</a></div><div id="page-content"><div id="preamble"><h1>Apache MPM worker</h1><div class="toplang"><p><span>Available Languages: </span><a href="../de/mod/worker.html" hreflang="de" rel="alternate" title="Deutsch"> de </a> |<a href="../en/mod/worker.html" title="English"> en </a> |<a href="../es/mod/worker.html" hreflang="es" rel="alternate" title="Espa駉l"> es </a> |<a href="../ja/mod/worker.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a></p></div><table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Multi-Processing Module implementing a hybrid multi-threaded multi-process web server</td></tr><tr><th><a href="module-dict.html#Status">Status:</a></th><td>MPM</td></tr><tr><th><a href="module-dict.html#ModuleIdentifier">Module營dentifier:</a></th><td>mpm_worker_module</td></tr><tr><th><a href="module-dict.html#SourceFile">Source燜ile:</a></th><td>worker.c</td></tr></table><h3>Summary</h3> <p>This Multi-Processing Module (MPM) implements a hybrid multi-process multi-threaded server. By using threads to serve requests, it is able to serve a large number of requests with less system resources than a process-based server. Yet it retains much of the stability of a process-based server by keeping multiple processes available, each with many threads.</p> <p>The most important directives used to control this MPM are <code class="directive"><a href="../mod/mpm_common.html#threadsperchild">ThreadsPerChild</a></code>, which controls the number of threads deployed by each child process and <code class="directive"><a href="../mod/mpm_common.html#maxclients">MaxClients</a></code>, which controls the maximum total number of threads that may be launched.</p></div><div id="quickview"><h3 class="directives">Directives</h3><ul id="toc"><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#acceptmutex">AcceptMutex</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#coredumpdirectory">CoreDumpDirectory</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#enableexceptionhook">EnableExceptionHook</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#group">Group</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#listen">Listen</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#listenbacklog">ListenBacklog</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#lockfile">LockFile</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#maxclients">MaxClients</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#maxmemfree">MaxMemFree</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#maxrequestsperchild">MaxRequestsPerChild</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#maxsparethreads">MaxSpareThreads</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#minsparethreads">MinSpareThreads</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#pidfile">PidFile</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#scoreboardfile">ScoreBoardFile</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#sendbuffersize">SendBufferSize</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#serverlimit">ServerLimit</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#startservers">StartServers</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#threadlimit">ThreadLimit</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#threadsperchild">ThreadsPerChild</a></li><li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#user">User</a></li></ul><h3>Topics</h3><ul id="topics"><li><img alt="" src="../images/down.gif" /> <a href="#how-it-works">How it Works</a></li></ul><h3>See also</h3><ul class="seealso"><li><a href="../bind.html">Setting which addresses and ports Apacheuses</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="how-it-works" id="how-it-works">How it Works</a></h2> <p>A single control process (the parent) is responsible for launching child processes. Each child process creates a fixed number of server threads as specified in the <code class="directive"><a href="../mod/mpm_common.html#threadsperchild">ThreadsPerChild</a></code> directive, as well as a listener thread which listens for connections and passes them to a server thread for processing when they arrive.</p> <p>Apache always tries to maintain a pool of <dfn>spare</dfn> or idle server threads, which stand ready to serve incoming requests. In this way, clients do not need to wait for a new threads or processes to be created before their requests can be served. The number of processes that will initially launched is set by the <code class="directive"><a href="../mod/mpm_common.html#startservers">StartServers</a></code> directive. Then during operation, Apache assesses the total number of idle threads in all processes, and forks or kills processes to keep this number within the boundaries specified by <code class="directive"><a href="../mod/mpm_common.html#minsparethreads">MinSpareThreads</a></code> and <code class="directive"><a href="../mod/mpm_common.html#maxsparethreads">MaxSpareThreads</a></code>. Since this process is very self-regulating, it is rarely necessary to modify these directives from their default values. The maximum number of clients that may be served simultaneously (i.e., the maximum total number of threads in all processes) is determined by the <code class="directive"><a href="../mod/mpm_common.html#maxclients">MaxClients</a></code> directive. The maximum number of active child processes is determined by the <code class="directive"><a href="../mod/mpm_common.html#maxclients">MaxClients</a></code> directive divided by the <code class="directive"><a href="../mod/mpm_common.html# threadsperchild"> ThreadsPerChild</a></code> directive.</p> <p>Two directives set hard limits on the number of active child processes and the number of server threads in a child process, and can only be changed by fully stopping the server and then starting it again. <code class="directive"><a href="../mod/mpm_common.html#serverlimit ">ServerLimit </a></code> is a hard limit on the number of active child processes, and must be greater than or equal to the <code class="directive"><a href="../mod/mpm_common.html#maxclients">MaxClients</a></code> directive divided by the <code class="directive"><a href="../mod/mpm_common.html# threadsperchild"> ThreadsPerChild</a></code> directive. <code class="directive"><a href="../mod/mpm_common.html#threadlimit">ThreadLimit</a></code> is a hard limit of the number of server threads, and must be greater than or equal to the <code class="directive"><a href="../mod/mpm_common.html#threadsperchild">ThreadsPerChild</a></code> directive. If non-default values are specified for these directives, they should appear before other <code class="module"><a href="../mod/worker.html">worker</a></code> directives.</p> <p>In addition to a the set of active child processes, there may be additional child processes which are terminating but where at least one server thread is still handling an existing client connection. Up to <code class="directive"><a href="../mod/mpm_common.html#maxclients">MaxClients</a></code> terminating processes may be present, though the actual number can be expected to be much smaller. This behavior can be avoided by disabling the termination of individual child processes, which is achieved by the following:</p> <ul> <li>set the value of <code class="directive"><a href="../mod/mpm_common.html# maxrequestsperchild"> MaxRequestsPerChild</a></code> to zero</li> <li>set the value of <code class="directive"><a href="../mod/mpm_common.html# maxsparethreads"> MaxSpareThreads</a></code> to the same value as <code class="directive"><a href="../mod/mpm_common.html#maxclients">MaxClients</a></code></li> </ul> <p>A typical configuration of the process-thread controls in the <code class="module"><a href="../mod/worker.html">worker</a></code> MPM could look as follows:</p> <div class="example"><p><code> ServerLimit 16<br /> StartServers 2<br /> MaxClients 150<br /> MinSpareThreads 25<br /> MaxSpareThreads 75<br /> ThreadsPerChild 25 </code></p></div> <p>While the parent process is usually started as <code>root</code> under Unix in order to bind to port 80, the child processes and threads are launched by Apache as a less-privileged user. The <code class="directive"><a href="../mod/mpm_common.html#user">User</a></code> and <code class="directive"><a href="../mod/mpm_common.html#group">Group</a></code> directives are used to set the privileges of the Apache child processes. The child processes must be able to read all the content that will be served, but should have as few privileges beyond that as possible. In addition, unless <code class="program"><a href="../programs/suexec.html">suexec</a></code> is used, these directives also set the privileges which will be inherited by CGI scripts.</p> <p><code class="directive"><a href="../mod/mpm_common.html#maxrequestsperchild">MaxRequestsPerChild</a></code> controls how frequently the server recycles processes by killing old ones and launching new ones.</p></div></div><div class="bottomlang"><p><span>Available Languages: </span><a href="../de/mod/worker.html" hreflang="de" rel="alternate" title="Deutsch"> de </a> |<a href="../en/mod/worker.html" title="English"> en </a> |<a href="../es/mod/worker.html" hreflang="es" rel="alternate" title="Espa駉l"> es </a> |<a href="../ja/mod/worker.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a></p></div><div id="footer"><p class="apache">Copyright 1995-2005 The Apache Software Foundation or its licensors, as applicable.<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>⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -