APC - Alternative PHP Cache

The Alternative PHP Cache (APC) is a free and open opcode cache for PHP. Its goal is to provide a free, open, and robust framework for caching and optimizing PHP intermediate code. Besides a opcode cache it provides a user cache for storing application data. This module uses the APC user cache as a cache backend for Drupal.

Use APC for caches that do not change often and will not grow too big to avoid fragmentation. The default setting of APC will allow you to store 32 MiB for the opcode cache and the user cache combined. Make sure you tweak this according to your website's needs. An example configuration could be to cache 'cache' and 'cache_bootstrap' in APC; 'cache_field' and 'cache_menu' in Memcached and store 'cache_filter' in the database

What is the difference of this module compared to other caching modules:

• Memcache
  • Memcache is used by installing a PHP extension that communicates with a Memcache deamon run on the same or a different machine using TCP. APC is also an extension and is often activated because it is used as opcode cache. APC allows direct access to the cache in memory were memcache first needs to communicate over TCP. Memcache should be used for caches which can get large or change often like 'cache_field' and 'cache_menu'.
  • Multiple webnodes connect to the same Memcache deamon and use the same cache. With APC all the webnodes have their own cache. For caches which do not change often like 'cache' and 'cache_bootstrap' this is not a problem and gives a speed gain compared to Memcache.

Maintainers

• Drupal 7: R.Muilwijk (sponsored by Trinoco)
• Drupal 5&6: Slantview

Installation instructions

Downloads