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diff --git a/APACHE_1_3_42/htdocs/manual/mod/mod_mmap_static.html b/APACHE_1_3_42/htdocs/manual/mod/mod_mmap_static.html new file mode 100644 index 0000000000..b246dbbfeb --- /dev/null +++ b/APACHE_1_3_42/htdocs/manual/mod/mod_mmap_static.html @@ -0,0 +1,129 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> + +<html xmlns="http://www.w3.org/1999/xhtml"> + <head> + <meta name="generator" content="HTML Tidy, see www.w3.org" /> + + <title>Apache module mod_mmap_static</title> + </head> + <!-- Background white, links blue (unvisited), navy (visited), red (active) --> + + <body bgcolor="#FFFFFF" text="#000000" link="#0000FF" + vlink="#000080" alink="#FF0000"> + <!--#include virtual="header.html" --> + + <h1 align="CENTER">Module mod_mmap_static</h1> + + <p>This module provides mmap()ing of a statically configured + list of frequently requested but not changed files.</p> + + <p><a href="module-dict.html#Status" + rel="Help"><strong>Status:</strong></a> Experimental<br /> + <a href="module-dict.html#SourceFile" + rel="Help"><strong>Source File:</strong></a> + mod_mmap_static.c<br /> + <a href="module-dict.html#ModuleIdentifier" + rel="Help"><strong>Module Identifier:</strong></a> + mmap_static_module<br /> + <a href="module-dict.html#Compatibility" + rel="Help"><strong>Compatibility:</strong></a> Available in + Apache 1.3 and later.</p> + + <h2>Summary</h2> + + <p>This is an <strong>experimental</strong> module and should + be used with care. You can easily create a broken site using + this module, read this document carefully. + <code>mod_mmap_static</code> maps a list of statically + configured files (via <code>MMapFile</code> directives in the + main server configuration) into memory through the system call + <code>mmap()</code>. This system call is available on most + modern Unix derivates, but not on all. There are sometimes + system-specific limits on the size and number of files that can + be mmap()d, experimentation is probably the easiest way to find + out.</p> + + <p>This mmap()ing is done once at server start or restart, + only. So whenever one of the mapped files changes on the + filesystem you <em>have</em> to restart the server by at least + sending it a HUP or USR1 signal (see the <a + href="../stopping.html">Stopping and Restarting</a> + documentation). To reiterate that point: if the files are + modified <em>in place</em> without restarting the server you + may end up serving requests that are completely bogus. You + should update files by unlinking the old copy and putting a new + copy in place. Most tools such as <code>rdist</code> and + <code>mv</code> do this. The reason why this modules doesn't + take care of changes to the files is that this check would need + an extra <code>stat()</code> every time which is a waste and + against the intent of I/O reduction.</p> + + <h2>Directives</h2> + + <ul> + <li><a href="#mmapfile">MMapFile</a></li> + </ul> + <hr /> + + <h2><a id="mmapfile" name="mmapfile">MMapFile</a> + directive</h2> + + <p><a href="directive-dict.html#Syntax" + rel="Help"><strong>Syntax:</strong></a> MMapFile + <em>filename</em> [<em>filename</em>] ...<br /> + <a href="directive-dict.html#Default" + rel="Help"><strong>Default:</strong></a> <em>None</em><br /> + <a href="directive-dict.html#Context" + rel="Help"><strong>Context:</strong></a> server-config<br /> + <a href="directive-dict.html#Override" + rel="Help"><strong>Override:</strong></a> <em>Not + applicable</em><br /> + <a href="directive-dict.html#Status" + rel="Help"><strong>Status:</strong></a> Experimental<br /> + <a href="directive-dict.html#Module" + rel="Help"><strong>Module:</strong></a> mod_mmap_static<br /> + <a href="directive-dict.html#Compatibility" + rel="Help"><strong>Compatibility:</strong></a> Only available + in Apache 1.3 or later</p> + + <p>The <code>MMapFile</code> directive maps one or more files + (given as whitespace separated arguments) into memory at server + startup time. They are automatically unmapped on a server + shutdown. When the files have changed on the filesystem at + least a HUP or USR1 signal should be send to the server to + re-mmap them.</p> + + <p>Be careful with the <em>filename</em> arguments: They have + to literally match the filesystem path Apache's URL-to-filename + translation handlers create. We cannot compare inodes or other + stuff to match paths through symbolic links <em>etc.</em> + because that again would cost extra <code>stat()</code> system + calls which is not acceptable. This module may or may not work + with filenames rewritten by <code>mod_alias</code> or + <code>mod_rewrite</code>... it is an experiment after all.</p> + + <p>Notice: You cannot use this for speeding up CGI programs or + other files which are served by special content handlers. It + can only be used for regular files which are usually served by + the Apache core content handler.</p> + Example: +<pre> + MMapFile /usr/local/apache/htdocs/index.html + +</pre> + + <p><strong>Note</strong>: don't bother asking for a for a + <code>MMapDir</code> directive which recursively maps all the + files in a directory. Use Unix the way it was meant to be used. + For example, see the <a href="core.html#include">Include</a> + directive, and consider this command:</p> +<pre> + find /www/htdocs -type f -print \ + | sed -e 's/.*/mmapfile &/' > /www/conf/mmap.conf + +</pre> + <!--#include virtual="footer.html" --> + </body> +</html> + |