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<!DOCTYPE modulesynopsis SYSTEM "../style/modulesynopsis.dtd">
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<modulesynopsis metafile="mod_disk_cache.xml.meta">

<name>mod_disk_cache</name>
<description>Content cache storage manager keyed to URIs</description>
<status>Extension</status>
<sourcefile>mod_disk_cache.c</sourcefile>
<identifier>disk_cache_module</identifier>

<summary>
    <p><module>mod_disk_cache</module> implements a disk based storage
    manager. It is primarily of use in conjunction with
    <module>mod_cache</module>.</p>

    <p>Content is stored in and retrieved from the cache using URI based
    keys. Content with access protection is not cached.</p>

    <p><program>htcacheclean</program> can be used to maintain the cache
       size at a maximum level.</p>

    <note><title>Note:</title>
      <p><module>mod_disk_cache</module> requires the services of
      <module>mod_cache</module>.</p>
    </note>
    <note><title>Note:</title>
      <p><module>mod_disk_cache</module> uses the sendfile feature to
      serve files from the cache when supported by the platform, and
      when enabled with <directive module="core">EnableSendfile</directive>.
      However, per-directory and .htaccess configuration of
      <directive module="core">EnableSendfile</directive> are ignored by
      <module>mod_disk_cache</module> as the corresponding settings are not
      available to the module when a request is being served from the
      cache.</p>
    </note>
</summary>

<directivesynopsis>
<name>CacheRoot</name>
<description>The directory root under which cache files are
stored</description>
<syntax>CacheRoot <var>directory</var></syntax>
<contextlist><context>server config</context><context>virtual host</context>
</contextlist>

<usage>
    <p>The <directive>CacheRoot</directive> directive defines the name of
    the directory on the disk to contain cache files. If the <module
    >mod_disk_cache</module> module has been loaded or compiled in to the
    Apache server, this directive <em>must</em> be defined. Failing to
    provide a value for <directive>CacheRoot</directive> will result in
    a configuration file processing error. The <directive
    module="mod_disk_cache">CacheDirLevels</directive> and <directive
    module="mod_disk_cache">CacheDirLength</directive> directives define
    the structure of the directories under the specified root directory.</p>

    <example>
      CacheRoot c:/cacheroot
    </example>
</usage>
</directivesynopsis>

<directivesynopsis>
<name>CacheDirLevels</name>
<description>The number of levels of subdirectories in the
cache.</description>
<syntax>CacheDirLevels <var>levels</var></syntax>
<default>CacheDirLevels 3</default>
<contextlist><context>server config</context><context>virtual host</context>
</contextlist>

<usage>
    <p>The <directive>CacheDirLevels</directive> directive sets the number
    of subdirectory levels in the cache. Cached data will be saved this
    many directory levels below the <directive module="mod_disk_cache"
    >CacheRoot</directive> directory.</p>

    <note>
      <p>The result of <directive>CacheDirLevels</directive>*
      <directive module="mod_disk_cache">CacheDirLength</directive> must
      not be higher than 20.</p>
    </note>

    <example>
      CacheDirLevels  5
    </example>
</usage>
</directivesynopsis>

<directivesynopsis>
<name>CacheDirLength</name>
<description>The number of characters in subdirectory names</description>
<syntax>CacheDirLength <var>length</var></syntax>
<default>CacheDirLength 2</default>
<contextlist><context>server config</context><context>virtual host</context>
</contextlist>

<usage>
    <p>The <directive>CacheDirLength</directive> directive sets the number
    of characters for each subdirectory name in the cache hierarchy.</p>

    <note>
      <p>The result of <directive module="mod_disk_cache"
      >CacheDirLevels</directive>* <directive>CacheDirLength</directive>
      must not be higher than 20.</p>
    </note>

    <example>
      CacheDirLength  4
    </example>
</usage>
</directivesynopsis>

<directivesynopsis>
<name>CacheMinFileSize</name>
<description>The minimum size (in bytes) of a document to be placed in the
cache</description>
<syntax>CacheMinFileSize <var>bytes</var></syntax>
<default>CacheMinFileSize 1</default>
<contextlist><context>server config</context><context>virtual host</context>
</contextlist>

<usage>
    <p>The <directive>CacheMinFileSize</directive> directive sets the
    minimum size, in bytes, for a document to be considered for storage
    in the cache.</p>

    <example>
      CacheMinFileSize 64
    </example>
</usage>
</directivesynopsis>

<directivesynopsis>
<name>CacheMaxFileSize</name>
<description>The maximum size (in bytes) of a document to be placed in the
cache</description>
<syntax>CacheMaxFileSize <var>bytes</var></syntax>
<default>CacheMaxFileSize 1000000</default>
<contextlist><context>server config</context><context>virtual host</context>
</contextlist>

<usage>
    <p>The <directive>CacheMaxFileSize</directive> directive sets the
    maximum size, in bytes, for a document to be considered for storage in
    the cache.</p>

    <example>
      CacheMaxFileSize 64000
    </example>
</usage>
</directivesynopsis>

</modulesynopsis>
