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Posted to cvs@httpd.apache.org by re...@apache.org on 2002/11/06 16:30:28 UTC
cvs commit: httpd-2.0/docs/manual/mod mod_mem_cache.xml
rederpj 2002/11/06 07:30:27
Modified: docs/manual/mod mod_mem_cache.xml
Log:
Updates to the mod_mem_cache.xml file to update formatting, improve
detail and accuracy, and to align with what the code does.
Revision Changes Path
1.3 +91 -74 httpd-2.0/docs/manual/mod/mod_mem_cache.xml
Index: mod_mem_cache.xml
===================================================================
RCS file: /home/cvs/httpd-2.0/docs/manual/mod/mod_mem_cache.xml,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -r1.2 -r1.3
--- mod_mem_cache.xml 3 Oct 2002 20:29:47 -0000 1.2
+++ mod_mem_cache.xml 6 Nov 2002 15:30:27 -0000 1.3
@@ -14,126 +14,143 @@
<note type="warning">
This module is experimental. Documentation is still under development...
</note>
- <p>mod_mem_cache implements an in-memory based storage manager.
- mod_mem_cache can be configured to operate in two modes: caching open file
- descriptors or caching objects in heap storage. <em>mod_mem_cache</em>
- is most useful when used to cache locally generated content or to cache
- backend server content for <module>mod_proxy</module> configured for ProxyPass
- (aka <em>reverse proxy</em>)</p>
-<note>
- <p><module>mod_mem_cache</module> requires the services of <module>mod_cache</module>.</p>
-</note>
- <p>Content stored and retrived keyed to the URL. Content with
- access protections is not cached.</p>
+ <p><module>mod_mem_cache</module> implements a memory based storage manager.
+ <module>mod_mem_cache</module> can be configured to operate in two modes:
+ caching open file descriptors or caching objects in heap storage.
+ <module>mod_mem_cache</module> is most useful when used to cache locally
+ generated content or to cache backend server content for
+ <module>mod_proxy</module> configured for
+ <directive module="mod_proxy">ProxyPass</directive> (aka <dfn>reverse proxy</dfn>)</p>
+
+ <p>Content is stored in and retrieved from the cache using URI based keys. Content with
+ access protection is not cached.</p>
+
+ <note><title>Note:</title>
+ <p><module>mod_mem_cache</module> requires the services of <module>mod_cache</module>.</p>
+ </note>
</summary>
<directivesynopsis>
<name>MCacheSize</name>
<description>The maximum amount of memory used by the cache in KBytes</description>
-<syntax>MCacheSize <em>KBytes</em></syntax>
+<syntax>MCacheSize <var>KBytes</var></syntax>
<default>MCacheSize 100</default>
-<contextlist><context>server config</context></contextlist>
+<contextlist><context>server config</context><context>virtual host</context>
+</contextlist>
<usage>
- <p>The <directive>MCacheSize</directive> directive sets the desired space
- usage of the cache, in KBytes (1024-byte units). If a new entry needs to be
- inserted in the cache and the size of the entry is greather than the
- remaining size, entries will be removed until the new entry could be cached.
- The removed entry is decided base on the <directive>MCacheRemovalAlgorithm</directive> algorithm</p>
-
-<note type="warning">
- The size must be greater than <directive>MCacheMaxObjectSize</directive>.
-</note>
-
-<example>
- MCacheSize 700000 <br />
-</example>
+ <p>The <directive>MCacheSize</directive> directive sets the maximum amount of memory
+ to be used by the cache, in KBytes (1024-byte units). If a new object needs to be
+ inserted in the cache and the size of the object is greater than the
+ remaining memory, objects will be removed until the new object can be cached.
+ The object to be removed is selected using the algorithm specified by
+ <directive>MCacheRemovalAlgorithm</directive>.</p>
+
+ <note type="warning"><title>Note:</title>
+ The <directive>MCacheSize</directive> value must be greater than the value
+ specified by the <directive>MCacheMaxObjectSize</directive> directive.
+ </note>
+
+ <example>
+ MCacheSize 700000<br />
+ </example>
</usage>
</directivesynopsis>
<directivesynopsis>
<name>MCacheMaxObjectCount</name>
<description>The maximum number of objects allowed to be placed in the cache</description>
-<syntax>MCacheMaxObjectCount <em>value</em></syntax>
+<syntax>MCacheMaxObjectCount <var>value</var></syntax>
<default>MCacheMaxObjectCount 1009</default>
-<contextlist><context>server config</context></contextlist>
+<contextlist><context>server config</context><context>virtual host</context>
+</contextlist>
<usage>
<p>The <directive>MCacheMaxObjectCount</directive> directive sets the maximum
- number of objects to be cached. If a new entry needs to be
- inserted in the cache and the maximum number of objects is reached, an entry
- will be removed to allow the new entry be cached. </p>
-
-<note>
- The value of <directive>MCacheMaxObjectCount</directive> is used to create
- the open hash table.
-</note>
-<example>
- MCacheMaxObjectCount 13001 <br />
-</example>
+ number of objects to be cached. If a new object needs to be inserted in the cache
+ and the maximum number of objects has been reached, an object will be removed
+ to allow the new object to be cached. The object to be removed is selected using
+ the algorithm specified by <directive>MCacheRemovalAlgorithm</directive>.</p>
+
+ <note><title>Note:</title>
+ The value of <directive>MCacheMaxObjectCount</directive> is used to create
+ the open hash table.
+ </note>
+
+ <example>
+ MCacheMaxObjectCount 13001<br />
+ </example>
</usage>
</directivesynopsis>
<directivesynopsis>
<name>MCacheMinObjectSize</name>
-<description>The minimum size (in bytes) of an object to be placed in the cache</description>
-<syntax>MCacheMinObjectSize <em>bytes</em></syntax>
+<description>The minimum size (in bytes) of a document to be allowed in the
+cache</description>
+<syntax>MCacheMinObjectSize <var>bytes</var></syntax>
<default>MCacheMinObjectSize 0</default>
-<contextlist><context>server config</context></contextlist>
+<contextlist><context>server config</context><context>virtual host</context>
+</contextlist>
<usage>
<p>The <directive>MCacheMinObjectSize</directive> directive sets the minimum
- size in bytes of an object to be cached.</p>
+ size in bytes of a document for it to be considered cacheable.</p>
-<example>
- MCacheMinObjectSize 10000 <br />
-</example>
+ <example>
+ MCacheMinObjectSize 10000<br />
+ </example>
</usage>
</directivesynopsis>
<directivesynopsis>
<name>MCacheMaxObjectSize</name>
-<description>The maximum size (in bytes) of an object to be placed in the cache</description>
-<syntax>MCacheMaxObjectSize <em>bytes</em></syntax>
+<description>The maximum size (in bytes) of a document allowed in the
+cache</description>
+<syntax>MCacheMaxObjectSize <var>bytes</var></syntax>
<default>MCacheMaxObjectSize 10000</default>
-<contextlist><context>server config</context></contextlist>
+<contextlist><context>server config</context><context>virtual host</context>
+</contextlist>
<usage>
<p>The <directive>MCacheMaxObjectSize</directive> directive sets the maximum
- size of an object to be cached.</p>
+ allowable size, in bytes, of a document for it to be considered cacheable.</p>
-<note type="warning">
- The size must be greater than <directive>MCacheMinObjectSize</directive>.
-</note>
-
-<example>
- MCacheMaxObjectSize 6400000 <br />
-</example>
+ <note type="warning"><title>Note:</title>
+ The value of <directive>MCacheMaxObjectSize</directive> must be greater
+ than the value specified by the <directive>MCacheMinObjectSize</directive>
+ directive.
+ </note>
+
+ <example>
+ MCacheMaxObjectSize 6400000<br />
+ </example>
</usage>
</directivesynopsis>
<directivesynopsis>
<name>MCacheRemovalAlgorithm</name>
-<description>The algorithm used to remove entries from the cache</description>
-<syntax>MCacheRemovalAlgorithm <em>algorithm</em></syntax>
+<description>The algorithm used to select documents for removal from the
+cache</description>
+<syntax>MCacheRemovalAlgorithm <code>LRU|GDSF</code></syntax>
<default>MCacheRemovalAlgorithm GDSF</default>
-<contextlist><context>server config</context></contextlist>
+<contextlist><context>server config</context><context>virtual host</context>
+</contextlist>
<usage>
- <p>The <directive>MCacheRemovalAlgorithm</directive> directive sets the algorithm
- used to remove entries from the cache.
- Two choices are available: <br />
- LRU (Least Recently Used): LRU removes the objects that have not been
- accessed for the longest time.<br />
- GDSF (GreadyDual-Size): This algorithm assigns priority to cached objects
- based on the coast of a cache miss and the size of the object. Objects with
- smallest priority are removed first.</p>
-
-<example>
- MCacheRemovalAlgorithm GDSF <br />
- MCacheRemovalAlgorithm LRU <br />
-</example>
+ <p>The <directive>MCacheRemovalAlgorithm</directive> directive specifies
+ the algorithm used to select documents for removal from the cache.
+ Two choices are available:<br />
+ <code>LRU</code> (Least Recently Used): <code>LRU</code> removes the
+ documents that have not been accessed for the longest time.<br />
+ <code>GDSF</code> (GreadyDual-Size): <code>GDSF</code> assigns a priority
+ to cached documents based on the cost of a cache miss and the size of
+ the document. Documents with the lowest priority are removed first.</p>
+
+ <example>
+ MCacheRemovalAlgorithm GDSF<br />
+ MCacheRemovalAlgorithm LRU<br />
+ </example>
</usage>
</directivesynopsis>
-</modulesynopsis>
\ No newline at end of file
+</modulesynopsis>