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diff --git a/docs/manual/mod/mod_cache_disk.html.en b/docs/manual/mod/mod_cache_disk.html.en new file mode 100644 index 0000000..9b0c0fd --- /dev/null +++ b/docs/manual/mod/mod_cache_disk.html.en @@ -0,0 +1,292 @@ +<?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> +<meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type" /> +<!-- + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + This file is generated from xml source: DO NOT EDIT + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + --> +<title>mod_cache_disk - Apache HTTP Server Version 2.4</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 rel="stylesheet" type="text/css" href="../style/css/prettify.css" /> +<script src="../style/scripts/prettify.min.js" type="text/javascript"> +</script> + +<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="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p> +<p class="apache">Apache HTTP Server Version 2.4</p> +<img alt="" src="../images/feather.png" /></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 2.4</a> > <a href="./">Modules</a></div> +<div id="page-content"> +<div id="preamble"><h1>Apache Module mod_cache_disk</h1> +<div class="toplang"> +<p><span>Available Languages: </span><a href="../en/mod/mod_cache_disk.html" title="English"> en </a> | +<a href="../fr/mod/mod_cache_disk.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | +<a href="../ja/mod/mod_cache_disk.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | +<a href="../ko/mod/mod_cache_disk.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p> +</div> +<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Disk based storage module for the HTTP caching filter.</td></tr> +<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>cache_disk_module</td></tr> +<tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>mod_cache_disk.c</td></tr></table> +<h3>Summary</h3> + + <p><code class="module"><a href="../mod/mod_cache_disk.html">mod_cache_disk</a></code> implements a disk based storage + manager for <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code>.</p> + + <p>The headers and bodies of cached responses are stored separately on + disk, in a directory structure derived from the md5 hash of the cached + URL.</p> + + <p>Multiple content negotiated responses can be stored concurrently, + however the caching of partial content is not yet supported by this + module.</p> + + <p>Atomic cache updates to both header and body files are achieved + without the need for locking by storing the device and inode numbers of + the body file within the header file. This has the side effect that + cache entries manually moved into the cache will be ignored.</p> + + <p>The <code class="program"><a href="../programs/htcacheclean.html">htcacheclean</a></code> tool is provided to list cached + URLs, remove cached URLs, or to maintain the size of the disk cache + within size and/or inode limits. The tool can be run on demand, or + can be daemonized to offer continuous monitoring of directory sizes.</p> + + <div class="note"><h3>Note:</h3> + <p><code class="module"><a href="../mod/mod_cache_disk.html">mod_cache_disk</a></code> requires the services of + <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code>, which must be + loaded before mod_cache_disk.</p> + </div> + <div class="note"><h3>Note:</h3> + <p><code class="module"><a href="../mod/mod_cache_disk.html">mod_cache_disk</a></code> uses the sendfile feature to + serve files from the cache when supported by the platform, and + when enabled with <code class="directive"><a href="../mod/core.html#enablesendfile">EnableSendfile</a></code>. + However, per-directory and .htaccess configuration of + <code class="directive"><a href="../mod/core.html#enablesendfile">EnableSendfile</a></code> are ignored by + <code class="module"><a href="../mod/mod_cache_disk.html">mod_cache_disk</a></code> as the corresponding settings are not + available to the module when a request is being served from the + cache.</p> + </div> +</div> +<div id="quickview"><a href="https://www.apache.org/foundation/contributing.html" class="badge"><img src="https://www.apache.org/images/SupportApache-small.png" alt="Support Apache!" /></a><h3 class="directives">Directives</h3> +<ul id="toc"> +<li><img alt="" src="../images/down.gif" /> <a href="#cachedirlength">CacheDirLength</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#cachedirlevels">CacheDirLevels</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#cachemaxfilesize">CacheMaxFileSize</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#cacheminfilesize">CacheMinFileSize</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#cachereadsize">CacheReadSize</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#cachereadtime">CacheReadTime</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#cacheroot">CacheRoot</a></li> +</ul> +<h3>Bugfix checklist</h3><ul class="seealso"><li><a href="https://www.apache.org/dist/httpd/CHANGES_2.4">httpd changelog</a></li><li><a href="https://bz.apache.org/bugzilla/buglist.cgi?bug_status=__open__&list_id=144532&product=Apache%20httpd-2&query_format=specific&order=changeddate%20DESC%2Cpriority%2Cbug_severity&component=mod_cache_disk">Known issues</a></li><li><a href="https://bz.apache.org/bugzilla/enter_bug.cgi?product=Apache%20httpd-2&component=mod_cache_disk">Report a bug</a></li></ul><h3>See also</h3> +<ul class="seealso"> +<li><code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code></li> +<li><code class="module"><a href="../mod/mod_cache_socache.html">mod_cache_socache</a></code></li> +<li><a href="../caching.html">Caching Guide</a></li> +<li><a href="#comments_section">Comments</a></li></ul></div> + +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="CacheDirLength" id="CacheDirLength">CacheDirLength</a> <a name="cachedirlength" id="cachedirlength">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>The number of characters in subdirectory names</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheDirLength <var>length</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheDirLength 2</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache_disk</td></tr> +</table> + <p>The <code class="directive">CacheDirLength</code> directive sets the number + of characters for each subdirectory name in the cache hierarchy. It can + be used in conjunction with <code class="directive">CacheDirLevels</code> to + determine the approximate structure of your cache hierarchy.</p> + <p>A high value for <code class="directive">CacheDirLength</code> combined + with a low value for <code class="directive">CacheDirLevels</code> will result in + a relatively flat hierarchy, with a large number of subdirectories at each + level.</p> + + <div class="note"> + <p>The result of <code class="directive"><a href="#cachedirlevels">CacheDirLevels</a></code>* <code class="directive">CacheDirLength</code> + must not be higher than 20.</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="CacheDirLevels" id="CacheDirLevels">CacheDirLevels</a> <a name="cachedirlevels" id="cachedirlevels">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>The number of levels of subdirectories in the +cache.</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheDirLevels <var>levels</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheDirLevels 2</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache_disk</td></tr> +</table> + <p>The <code class="directive">CacheDirLevels</code> directive sets the number + of subdirectory levels in the cache. Cached data will be saved this + many directory levels below the <code class="directive"><a href="#cacheroot">CacheRoot</a></code> directory.</p> + <p>A high value for <code class="directive">CacheDirLevels</code> combined + with a low value for <code class="directive">CacheDirLength</code> will result in + a relatively deep hierarchy, with a small number of subdirectories at each + level.</p> + + <div class="note"> + <p>The result of <code class="directive">CacheDirLevels</code>* + <code class="directive"><a href="#cachedirlength">CacheDirLength</a></code> must + not be higher than 20.</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="CacheMaxFileSize" id="CacheMaxFileSize">CacheMaxFileSize</a> <a name="cachemaxfilesize" id="cachemaxfilesize">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>The maximum size (in bytes) of a document to be placed in the +cache</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheMaxFileSize <var>bytes</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheMaxFileSize 1000000</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache_disk</td></tr> +</table> + <p>The <code class="directive">CacheMaxFileSize</code> directive sets the + maximum size, in bytes, for a document to be considered for storage in + the cache.</p> + + <pre class="prettyprint lang-config">CacheMaxFileSize 64000</pre> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="CacheMinFileSize" id="CacheMinFileSize">CacheMinFileSize</a> <a name="cacheminfilesize" id="cacheminfilesize">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>The minimum size (in bytes) of a document to be placed in the +cache</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheMinFileSize <var>bytes</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheMinFileSize 1</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache_disk</td></tr> +</table> + <p>The <code class="directive">CacheMinFileSize</code> directive sets the + minimum size, in bytes, for a document to be considered for storage + in the cache.</p> + + <pre class="prettyprint lang-config">CacheMinFileSize 64</pre> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="CacheReadSize" id="CacheReadSize">CacheReadSize</a> <a name="cachereadsize" id="cachereadsize">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>The minimum size (in bytes) of the document to read and be cached + before sending the data downstream</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheReadSize <var>bytes</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheReadSize 0</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache_disk</td></tr> +</table> + <p>The <code class="directive">CacheReadSize</code> directive sets the + minimum amount of data, in bytes, to be read from the backend before the + data is sent to the client. The default of zero causes all data read of + any size to be passed downstream to the client immediately as it arrives. + Setting this to a higher value causes the disk cache to buffer at least + this amount before sending the result to the client. This can improve + performance when caching content from a reverse proxy.</p> + + <p>This directive only takes effect when the data is being saved to the + cache, as opposed to data being served from the cache.</p> + + <pre class="prettyprint lang-config">CacheReadSize 102400</pre> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="CacheReadTime" id="CacheReadTime">CacheReadTime</a> <a name="cachereadtime" id="cachereadtime">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>The minimum time (in milliseconds) that should elapse while reading + before data is sent downstream</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheReadTime <var>milliseconds</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheReadTime 0</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache_disk</td></tr> +</table> + <p>The <code class="directive">CacheReadTime</code> directive sets the minimum amount + of elapsed time that should pass before making an attempt to send data + downstream to the client. During the time period, data will be buffered + before sending the result to the client. This can improve performance when + caching content from a reverse proxy.</p> + + <p>The default of zero disables this option.</p> + + <p>This directive only takes effect when the data is being saved to the + cache, as opposed to data being served from the cache. It is recommended + that this option be used alongside the + <code class="directive"><a href="#cachereadsize">CacheReadSize</a></code> directive to + ensure that the server does not buffer excessively should data arrive faster + than expected.</p> + + <pre class="prettyprint lang-config">CacheReadTime 1000</pre> + + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="CacheRoot" id="CacheRoot">CacheRoot</a> <a name="cacheroot" id="cacheroot">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>The directory root under which cache files are +stored</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheRoot <var>directory</var></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache_disk</td></tr> +</table> + <p>The <code class="directive">CacheRoot</code> directive defines the name of + the directory on the disk to contain cache files. If the <code class="module"><a href="../mod/mod_cache_disk.html">mod_cache_disk</a></code> module has been loaded or compiled in to the + Apache server, this directive <em>must</em> be defined. Failing to + provide a value for <code class="directive">CacheRoot</code> will result in + a configuration file processing error. The <code class="directive"><a href="#cachedirlevels">CacheDirLevels</a></code> and <code class="directive"><a href="#cachedirlength">CacheDirLength</a></code> directives define + the structure of the directories under the specified root directory.</p> + + <pre class="prettyprint lang-config">CacheRoot c:/cacheroot</pre> + + +</div> +</div> +<div class="bottomlang"> +<p><span>Available Languages: </span><a href="../en/mod/mod_cache_disk.html" title="English"> en </a> | +<a href="../fr/mod/mod_cache_disk.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | +<a href="../ja/mod/mod_cache_disk.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | +<a href="../ko/mod/mod_cache_disk.html" hreflang="ko" rel="alternate" title="Korean"> ko </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> +<script type="text/javascript"><!--//--><![CDATA[//><!-- +var comments_shortname = 'httpd'; +var comments_identifier = 'http://httpd.apache.org/docs/2.4/mod/mod_cache_disk.html'; +(function(w, d) { + if (w.location.hostname.toLowerCase() == "httpd.apache.org") { + d.write('<div id="comments_thread"><\/div>'); + var s = d.createElement('script'); + s.type = 'text/javascript'; + s.async = true; + s.src = 'https://comments.apache.org/show_comments.lua?site=' + comments_shortname + '&page=' + comments_identifier; + (d.getElementsByTagName('head')[0] || d.getElementsByTagName('body')[0]).appendChild(s); + } + else { + d.write('<div id="comments_thread">Comments are disabled for this page at the moment.<\/div>'); + } +})(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="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(); +} +//--><!]]></script> +</body></html>
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