1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
<?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>Shared Object Cache in Apache HTTP Server - Apache HTTP Server Version 2.5</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 id="manual-page" class="no-sidebar"><div id="page-header">
<p class="menu"><a href="./mod/">Modules</a> | <a href="./mod/quickreference.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 2.5</p>
<img alt="" src="./images/feather.gif" /></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 2.5</a></div><div id="page-content"><div id="preamble"><h1>Shared Object Cache in Apache HTTP Server</h1>
<div class="toplang">
<p><span>Available Languages: </span><a href="./en/socache.html" title="English"> en </a> |
<a href="./fr/socache.html" hreflang="fr" rel="alternate" title="Fran�ais"> fr </a></p>
</div>
<p>The Shared Object Cache provides a means to share simple data
across all a server's workers, regardless of <a href="mpm.html">thread
and process models</a>. It is used where the advantages of sharing
data across processes outweigh the performance overhead of
inter-process communication.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
<div class="section">
<h2><a name="providers" id="providers">Shared Object Cache Providers</a></h2>
<p>The shared object cache as such is an abstraction. Four different
modules implement it. To use the cache, one or more of these modules
must be present, and configured.</p>
<p>The only configuration required is to select which cache provider
to use. This is the responsibility of modules using the cache, and
they enable selection using directives such as
<code class="directive"><a href="./mod/mod_cache_socache.html#cachesocache">CacheSocache</a></code>,
<code class="directive"><a href="./mod/mod_authn_socache.html#authncachesocache">AuthnCacheSOCache</a></code>,
<code class="directive"><a href="./mod/mod_ssl.html#sslsessioncache">SSLSessionCache</a></code>, and
<code class="directive"><a href="./mod/mod_ssl.html#sslstaplingcache">SSLStaplingCache</a></code>.</p>
<p>Currently available providers are:</p>
<dl>
<dt>"dbm" (<code class="module"><a href="./mod/mod_socache_dbm.html">mod_socache_dbm</a></code>)</dt>
<dd>This makes use of a DBM hash file.
The choice of underlying DBM used may be configurable
if the installed APR version supports multiple DBM implementations.</dd>
<dt>"dc" (<code class="module"><a href="./mod/mod_socache_dc.html">mod_socache_dc</a></code>)</dt>
<dd>This makes use of the <a href="http://www.distcache.org/">distcache</a>
distributed session caching libraries.</dd>
<dt>"memcache" (<code class="module"><a href="./mod/mod_socache_memcache.html">mod_socache_memcache</a></code>)</dt>
<dd>This makes use of the <a href="http://memcached.org/">memcached</a>
high-performance, distributed memory object caching system.</dd>
<dt>"shmcb" (<code class="module"><a href="./mod/mod_socache_shmcb.html">mod_socache_shmcb</a></code>)</dt>
<dd>This makes use of a high-performance cyclic buffer inside a
shared memory segment.</dd>
</dl>
<p>The API provides the following functions:</p>
<dl>
<dt>const char *create(ap_socache_instance_t **instance, const char *arg,
apr_pool_t *tmp, apr_pool_t *p);</dt>
<dd>Create a session cache based on the given configuration string.
The instance pointer returned in the instance paramater will be
passed as the first argument to subsequent invocations.</dd>
<dt>apr_status_t init(ap_socache_instance_t *instance, const char *cname,
const struct ap_socache_hints *hints,
server_rec *s, apr_pool_t *pool)</dt>
<dd>Initialize the cache. The cname must be of maximum length 16
characters, and uniquely identifies the consumer of the cache
within the server; using the module name is recommended, e.g.
"mod_ssl-sess". This string may be used within a filesystem
path so use of only alphanumeric [a-z0-9_-] characters is
recommended. If hints is non-NULL, it gives a set of hints for
the provider. Return APR error code.</dd>
<dt>void destroy(ap_socache_instance_t *instance, server_rec *s)</dt>
<dd>Destroy a given cache instance object.</dd>
<dt>apr_status_t store(ap_socache_instance_t *instance, server_rec *s,
const unsigned char *id, unsigned int idlen,
apr_time_t expiry,
unsigned char *data, unsigned int datalen,
apr_pool_t *pool)</dt>
<dd>Store an object in a cache instance.</dd>
<dt>apr_status_t retrieve(ap_socache_instance_t *instance, server_rec *s,
const unsigned char *id, unsigned int idlen,
unsigned char *data, unsigned int *datalen,
apr_pool_t *pool)</dt>
<dd>Retrieve a cached object.</dd>
<dt>apr_status_t remove(ap_socache_instance_t *instance, server_rec *s,
const unsigned char *id, unsigned int idlen,
apr_pool_t *pool)</dt>
<dd>Remove an object from the cache.</dd>
<dt>void status(ap_socache_instance_t *instance, request_rec *r, int flags)</dt>
<dd>Dump the status of a cache instance for mod_status.</dd>
<dt>apr_status_t iterate(ap_socache_instance_t *instance, server_rec *s,
void *userctx, ap_socache_iterator_t *iterator,
apr_pool_t *pool)</dt>
<dd>Dump all cached objects through an iterator callback.</dd>
</dl>
</div></div>
<div class="bottomlang">
<p><span>Available Languages: </span><a href="./en/socache.html" title="English"> en </a> |
<a href="./fr/socache.html" hreflang="fr" rel="alternate" title="Fran�ais"> fr </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/trunk/socache.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 2016 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/quickreference.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>
|
