diff options
Diffstat (limited to 'docs/manual/mod/mpm_common.html.en')
| -rw-r--r-- | docs/manual/mod/mpm_common.html.en | 63 |
1 files changed, 40 insertions, 23 deletions
diff --git a/docs/manual/mod/mpm_common.html.en b/docs/manual/mod/mpm_common.html.en index 2961403..d7a2fea 100644 --- a/docs/manual/mod/mpm_common.html.en +++ b/docs/manual/mod/mpm_common.html.en @@ -1,7 +1,7 @@ -<?xml version="1.0" encoding="ISO-8859-1"?> +<?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=ISO-8859-1" http-equiv="Content-Type" /> +<meta content="text/html; charset=UTF-8" http-equiv="Content-Type" /> <!-- XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX This file is generated from xml source: DO NOT EDIT @@ -28,9 +28,9 @@ <div class="toplang"> <p><span>Available Languages: </span><a href="../de/mod/mpm_common.html" hreflang="de" rel="alternate" title="Deutsch"> de </a> | <a href="../en/mod/mpm_common.html" title="English"> en </a> | -<a href="../fr/mod/mpm_common.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | +<a href="../fr/mod/mpm_common.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | <a href="../ja/mod/mpm_common.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | -<a href="../tr/mod/mpm_common.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p> +<a href="../tr/mod/mpm_common.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p> </div> <table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>A collection of directives that are implemented by more than one multi-processing module (MPM)</td></tr> @@ -87,6 +87,17 @@ switch before dumping core</td></tr> operating system is not configured to write core files to the working directory of the crashing processes.</p> + <div class="warning"> + <h3>Security note for Linux systems</h3> + + <p>Using this directive on Linux may allow other processes on + the system (if running with similar privileges, such as CGI + scripts) to attach to httpd children via the <code>ptrace</code> + system call. This may make weaken the protection from certain + security attacks. It is not recommended to use this directive + on production systems.</p> + </div> + <div class="note"><h3>Core Dumps on Linux</h3> <p>If Apache httpd starts as root and switches to another user, the Linux kernel <em>disables</em> core dumps even if the directory is @@ -237,15 +248,15 @@ including other causes.</a></li> <div class="directive-section"><h2><a name="ListenBackLog" id="ListenBackLog">ListenBackLog</a> <a name="listenbacklog" id="listenbacklog">Directive</a></h2> <table class="directive"> <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximum length of the queue of pending connections</td></tr> -<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ListenBacklog <var>backlog</var></code></td></tr> -<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ListenBacklog 511</code></td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ListenBackLog <var>backlog</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ListenBackLog 511</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><code class="module"><a href="../mod/event.html">event</a></code>, <code class="module"><a href="../mod/worker.html">worker</a></code>, <code class="module"><a href="../mod/prefork.html">prefork</a></code>, <code class="module"><a href="../mod/mpm_winnt.html">mpm_winnt</a></code>, <code class="module"><a href="../mod/mpm_netware.html">mpm_netware</a></code>, <code class="module"><a href="../mod/mpmt_os2.html">mpmt_os2</a></code></td></tr> </table> <p>The maximum length of the queue of pending connections. - Generally no tuning is needed or desired, however on some - systems it is desirable to increase this when under a TCP SYN + Generally no tuning is needed or desired; however on some + systems, it is desirable to increase this when under a TCP SYN flood attack. See the backlog parameter to the <code>listen(2)</code> system call.</p> @@ -275,7 +286,7 @@ in *BSDs.</td></tr> <p>A <var>ratio</var> between the number of (online) CPU cores and the number of listeners' buckets can be used to make Apache HTTP Server create <code>num_cpu_cores / ratio</code> listening buckets, each containing its - own <code class="directive">Listen</code>-ing socket(s) on the same port(s), and + own <code class="directive"><a href="#listen">Listen</a></code>-ing socket(s) on the same port(s), and then make each child handle a single bucket (with round-robin distribution of the buckets at children creation time).</p> @@ -316,7 +327,7 @@ in *BSDs.</td></tr> <p>This also means that multiple instances of Apache httpd configured on a same <code>IP:port</code> and with a positive <code class="directive">ListenCoresBucketsRatio</code> would start without an error too, and then run with incoming connections - evenly distributed accross both instances (this is NOT a recommendation or + evenly distributed across both instances (this is NOT a recommendation or a sensible usage in any case, but just a notice that it would prevent such possible issues to be detected).</p> <p>Within the same instance, Apache httpd will check and fail to start if @@ -349,7 +360,7 @@ will handle during its life</td></tr> <code>0</code>, then the process will never expire.</p> <p>Setting <code class="directive">MaxConnectionsPerChild</code> to a - non-zero value limits the amount of memory that process can consume + non-zero value limits the amount of memory that a process can consume by (accidental) memory leakage.</p> </div> @@ -397,9 +408,9 @@ simultaneously</td></tr> <code class="directive"><a href="#serverlimit">ServerLimit</a></code>.</p> <p>For threaded and hybrid servers (<em>e.g.</em> <code class="module"><a href="../mod/event.html">event</a></code> - or <code class="module"><a href="../mod/worker.html">worker</a></code>) <code class="directive">MaxRequestWorkers</code> restricts + or <code class="module"><a href="../mod/worker.html">worker</a></code>), <code class="directive">MaxRequestWorkers</code> restricts the total number of threads that will be available to serve clients. - For hybrid MPMs the default value is <code>16</code> (<code class="directive"><a href="#serverlimit">ServerLimit</a></code>) multiplied by the value of + For hybrid MPMs, the default value is <code>16</code> (<code class="directive"><a href="#serverlimit">ServerLimit</a></code>) multiplied by the value of <code>25</code> (<code class="directive"><a href="#threadsperchild">ThreadsPerChild</a></code>). Therefore, to increase <code class="directive">MaxRequestWorkers</code> to a value that requires more than 16 processes, you must also raise <code class="directive"><a href="#serverlimit">ServerLimit</a></code>.</p> @@ -424,7 +435,7 @@ simultaneously</td></tr> <p>For <code class="module"><a href="../mod/worker.html">worker</a></code> and <code class="module"><a href="../mod/event.html">event</a></code>, the default is <code>MaxSpareThreads 250</code>. These MPMs deal with idle threads on a server-wide basis. If there are too many idle threads in the - server then child processes are killed until the number of idle + server, then child processes are killed until the number of idle threads is less than this number. Additional processes/threads might be created if <code class="directive"><a href="#listencoresbucketsratio">ListenCoresBucketsRatio</a></code> is enabled.</p> @@ -475,7 +486,7 @@ spikes</td></tr> <p><code class="module"><a href="../mod/worker.html">worker</a></code> and <code class="module"><a href="../mod/event.html">event</a></code> use a default of <code>MinSpareThreads 75</code> and deal with idle threads on a server-wide - basis. If there aren't enough idle threads in the server then child + basis. If there aren't enough idle threads in the server, then child processes are created until the number of idle threads is greater than <var>number</var>. Additional processes/threads might be created if <code class="directive"><a href="#listencoresbucketsratio">ListenCoresBucketsRatio</a></code> @@ -483,7 +494,7 @@ spikes</td></tr> <p><code class="module"><a href="../mod/mpm_netware.html">mpm_netware</a></code> uses a default of <code>MinSpareThreads 10</code> and, since it is a single-process - MPM, tracks this on a server-wide bases.</p> + MPM, tracks this on a server-wide basis.</p> <p><code class="module"><a href="../mod/mpmt_os2.html">mpmt_os2</a></code> works similar to <code class="module"><a href="../mod/mpm_netware.html">mpm_netware</a></code>. For @@ -509,7 +520,7 @@ of the daemon</td></tr> </table> <p>The <code class="directive">PidFile</code> directive sets the file to which the server records the process id of the daemon. If the - filename is not absolute then it is assumed to be relative to the + filename is not absolute, then it is assumed to be relative to the <code class="directive"><a href="../mod/core.html#serverroot">ServerRoot</a></code>.</p> <div class="example"><h3>Example</h3><pre class="prettyprint lang-config">PidFile /var/run/apache.pid</pre> @@ -572,7 +583,7 @@ the child processes</td></tr> <p>File-based shared memory is useful for third-party applications that require direct access to the scoreboard.</p> - <p>If you use a <code class="directive">ScoreBoardFile</code> then + <p>If you use a <code class="directive">ScoreBoardFile</code>, then you may see improved speed by placing it on a RAM disk. But be careful that you heed the same warnings about log file placement and <a href="../misc/security_tips.html">security</a>.</p> @@ -782,6 +793,12 @@ per child process</td></tr> <p>The default value for <code class="directive">ThreadsPerChild</code> is <code>64</code> when used with <code class="module"><a href="../mod/mpm_winnt.html">mpm_winnt</a></code> and <code>25</code> when used with the others.</p> + + <p>The value of <code class="directive">ThreadsPerChild</code> can not exceed the + value of <code class="directive"><a href="#threadlimit">ThreadLimit</a></code>. If a + higher value is configured, it will be automatically reduced at start-up + and a warning will be logged. The relationship between these 2 directives + is explained in <code class="directive"><a href="#threadlimit">ThreadLimit</a></code>.</p> </div> <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> @@ -821,7 +838,7 @@ client connections</td></tr> will be achievable if <code class="directive">ThreadStackSize</code> is set to a value lower than the operating system default. This type of adjustment should only be made in a test environment which allows - the full set of web server processing can be exercised, as there + the full set of web server processing to be exercised, as there may be infrequent requests which require more stack to process. The minimum required stack size strongly depends on the modules used, but any change in the web server configuration can invalidate @@ -844,10 +861,10 @@ client connections</td></tr> <div class="bottomlang"> <p><span>Available Languages: </span><a href="../de/mod/mpm_common.html" hreflang="de" rel="alternate" title="Deutsch"> de </a> | <a href="../en/mod/mpm_common.html" title="English"> en </a> | -<a href="../fr/mod/mpm_common.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | +<a href="../fr/mod/mpm_common.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | <a href="../ja/mod/mpm_common.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | -<a href="../tr/mod/mpm_common.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </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 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> +<a href="../tr/mod/mpm_common.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </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/mod/mpm_common.html'; @@ -865,7 +882,7 @@ var comments_identifier = 'http://httpd.apache.org/docs/2.4/mod/mpm_common.html' } })(window, document); //--><!]]></script></div><div id="footer"> -<p class="apache">Copyright 2019 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="apache">Copyright 2024 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(); |