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diff --git a/rubbos/app/httpd-2.0.64/docs/manual/mod/perchild.html.en b/rubbos/app/httpd-2.0.64/docs/manual/mod/perchild.html.en new file mode 100644 index 00000000..3d557add --- /dev/null +++ b/rubbos/app/httpd-2.0.64/docs/manual/mod/perchild.html.en @@ -0,0 +1,266 @@ +<?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>perchild - 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/">Documentation</a> > <a href="../">Version 2.0</a> > <a href="./">Modules</a></div> +<div id="page-content"> +<div id="preamble"><h1>Apache MPM perchild</h1> +<div class="toplang"> +<p><span>Available Languages: </span><a href="../en/mod/perchild.html" title="English"> en </a></p> +</div> +<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Multi-Processing Module allowing for daemon processes serving +requests to be assigned a variety of different userids</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 Identifier:</a></th><td>mpm_perchild_module</td></tr> +<tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>perchild.c</td></tr></table> +<h3>Summary</h3> + + <div class="warning"> + This module is not functional. Development of this module is not + complete and is not currently active. Do not use + <code class="module"><a href="../mod/perchild.html">perchild</a></code> unless you are a programmer willing to + help fix it. + </div> + + <p>This Multi-Processing Module (MPM) implements a hybrid + multi-process, multi-threaded web server. A fixed number of + processes create threads to handle requests. Fluctuations in + load are handled by increasing or decreasing the number of + threads in each process.</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/down.gif" /> <a href="#assignuserid">AssignUserID</a></li> +<li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#bs2000account">BS2000Account</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#childperuserid">ChildPerUserID</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#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/down.gif" /> <a href="#maxthreadsperchild">MaxThreadsPerChild</a></li> +<li><img alt="" src="../images/right.gif" /> <a href="mpm_common.html#minsparethreads">MinSpareThreads</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#numservers">NumServers</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#receivebuffersize">ReceiveBufferSize</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#startthreads">StartThreads</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#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 Apache +uses</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 launches the number of child processes + indicated by the <code class="directive"><a href="#numservers">NumServers</a></code> + directive at server startup. Each child process creates threads as + specified in the <code class="directive"><a href="../mod/mpm_common.html#startthreads">StartThreads</a></code> directive. + The individual threads then + listen for connections and serve them 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 new + threads to be created. For each child process, Apache assesses + the number of idle threads and creates or destroys threads 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 + is determined by multiplying the number of server processes + that will be created (<code class="directive"><a href="#numservers">NumServers</a></code>) by the maximum + number of threads created in each process + (<code class="directive"><a href="../mod/mpm_common.html#maxthreadsperchild">MaxThreadsPerChild</a></code>).</p> + + <p>While the parent process is usually started as root 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> + + <h3><a name="user-ids" id="user-ids">Working with different user-IDs</a></h3> + <p>The <code class="module"><a href="../mod/perchild.html">perchild</a></code> MPM adds the extra ability to + specify that particular processes should serve requests under + different user-IDs. These user-IDs can then be associated with + specific virtual hosts. You have to use one <code class="directive"><a href="#childperuserid">ChildPerUserID</a></code> directive for + every user/group combination you want to be run. Then you can tie + particular virtual hosts to that user and group IDs.</p> + + <p>The following example runs 7 child processes. Two of them are run + under <code>user1</code>/<code>group1</code>. The next four are run + under <code>user2</code>/<code>group2</code> and the remaining + process uses 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> + of the main server:</p> + + <div class="example"><h3>Global config</h3><p><code> + NumServers 7<br /> + ChildPerUserID user1 group1 2<br /> + ChildPerUserID user2 group2 4 + </code></p></div> + + <p>Using unbalanced numbers of processes as above is useful, if the + particular virtual hosts produce different load. The assignment to + the virtual hosts is easily done as in the example below. In + conclusion with the example above the following assumes, that + <code>server2</code> has to serve about twice of the hits of + <code>server1</code>.</p> + + <div class="example"><h3>Example</h3><p><code> + NameVirtualHost *<br /> + <br /> + <VirtualHost *><br /> + <span class="indent"> + ServerName fallbackhost<br /> + # no assignment; use fallback<br /> + </span> + </VirtualHost><br /> + <br /> + <VirtualHost *><br /> + <span class="indent"> + ServerName server1<br /> + AssignUserID user1 group1<br /> + </span> + </VirtualHost><br /> + <br /> + <VirtualHost *><br /> + <span class="indent"> + ServerName server2<br /> + AssignUserID user2 group2<br /> + </span> + </VirtualHost> + </code></p></div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="AssignUserID" id="AssignUserID">AssignUserID</a> <a name="assignuserid" id="assignuserid">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Tie a virtual host to a user and group ID</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AssignUserID <var>user-id</var> <var>group-id</var></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>MPM</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>perchild</td></tr> +</table> + <p>Tie a virtual host to a specific user/group combination. Requests + addressed to the virtual host where this directive appears will be + served by a process running with the specified user and group ID.</p> + + <p>The user and group ID has to be assigned to a number of children + in the global server config using the <code class="directive"><a href="#childperuserid">ChildPerUserID</a></code> directive. See the section above for a + <a href="#user-ids">configuration example</a>.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ChildPerUserID" id="ChildPerUserID">ChildPerUserID</a> <a name="childperuserid" id="childperuserid">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Specify user ID and group ID for a number of child +processes</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ChildPerUserID <var>user-id</var> <var>group-id</var> +<var>num-children</var></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>MPM</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>perchild</td></tr> +</table> + <p>Specify a user ID and group ID for a number of child processes. + The third argument, <var>num-children</var>, is the number of child + processes to start with the specified user and group. It does + <em>not</em> represent a specific child number. In order to use this + directive, the server must be run initially as <code>root</code>. + If you start the server as a non-root user, it will fail to change + to the lesser privileged user.</p> + + <p>If the total number of child processes, found by totaling all of the + third arguments to all <code class="directive">ChildPerUserID</code> directives + in the config file, is less than <code class="directive"><a href="#numservers">NumServers</a></code>, then all remaining children will inherit 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> settings from the main server. + See the section above for a <a href="#user-ids">configuration + example</a>.</p> + + <div class="warning"><h3>Security</h3> + <p>Don't set <var>user-id</var> (or <var>group-id</var>) to + <code>root</code> unless you know exactly what you are doing, and + what the dangers are.</p> + </div> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="MaxThreadsPerChild" id="MaxThreadsPerChild">MaxThreadsPerChild</a> <a name="maxthreadsperchild" id="maxthreadsperchild">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximum number of threads per child process</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>MaxThreadsPerChild <var>number</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>MaxThreadsPerChild 64</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>MPM</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>perchild</td></tr> +</table> + <p>This directive sets the maximum number of threads that will be + created in each child process. To increase this value beyond its + default, it is necessary to change the value of the <code class="directive"><a href="../mod/mpm_common.html#threadlimit">ThreadLimit</a></code> directive and stop and + re-start the server.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="NumServers" id="NumServers">NumServers</a> <a name="numservers" id="numservers">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Total number of children alive at the same time</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>NumServers <var>number</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>NumServers 2</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>MPM</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>perchild</td></tr> +</table> + <p>The <code class="directive">NumServers</code> directive determines the number + of children alive at the same time. This number should be large enough to + handle the requests for the entire site. To increase this value beyond the + value of <code>8</code>, it is necessary to change the value of the + <code class="directive"><a href="../mod/mpm_common.html#serverlimit">ServerLimit</a></code> directive and stop + and re-start the server. See the section above for a <a href="#user-ids">configuration example</a>.</p> + +</div> +</div> +<div class="bottomlang"> +<p><span>Available Languages: </span><a href="../en/mod/perchild.html" title="English"> en </a></p> +</div><div id="footer"> +<p class="apache">Copyright 2009 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>
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