Memcache module provides handy procedural and object oriented interface to memcached, highly effective caching daemon, which was especially designed to decrease database load in dynamic web applications.
This module doesn't have native support of multiple servers, but you still can implement it yourself in your application. Establish several memcached connections, set priority level for each server etc.
More information about memcached can be found at http://www.danga.com/memcached/.
This module uses functions of zlib to support on-the-fly data compression. Zlib is required to install this module.
PHP 4.3.3 or newer is required to use the memcache extension.
This PECL extension is not bundled with PHP. Additional information such as new releases, downloads, source files, maintainer information, and a CHANGELOG, can be located here: http://pecl.php.net/package/memcache.
In order to use these functions you must compile PHP with MemCache support by using the --with-memcache[=DIR] option.
Table 1. MemCache Constants
|MEMCACHE_COMPRESSED (integer)||Used to turn on-the-fly data compression on with Memcache::set(), Memcache::add() and Memcache::replace().|
This extension has no configuration directives defined in php.ini.
There is only one resource type used in memcache module - it's the link identifier for a cache server connection.
Example 1. memcache extension overview example
In the above example, an object is being saved in the cache and then retrieved back. Object and other non-scalar types are serialized before saving, so it's impossible to store resources (i.e. connection identifiers and others) in the cache.