Installation

Step 1

Enable the module and verify the status page (/admin/reports/status) shows the APCu extension is installed.

Step 2

Choose whenever you want the APC extension for all the cache bins used from Drupal or just for some cache bins. APC normally has a limited memory available (32M) and should be used to cache the entries which are mostly used, since it is the cache closest (and maybe fastest) to PHP. When the memory allocated by APC is big enough to cache the entire Drupal cache you can follow Step 2b; otherwise you should follow Step 2a.

Step 2a

Add the following lines to your settings.php file

/**
 * APC cache settings.
 */
$conf['cache_backends'][] = 'sites/all/modules/apc/drupal_apc_cache.inc';
$conf['cache_class_cache'] = 'DrupalAPCCache';
$conf['cache_class_cache_bootstrap'] = 'DrupalAPCCache';

// Uncomment the following line to enable debugging.
// $conf['apc_show_debug'] = TRUE;

Step 2b

Add the following lines to your settings.php file.

/**
 * APC cache settings.
 */
$conf['cache_backends'][] = 'sites/all/modules/apc/drupal_apc_cache.inc';
$conf['cache_default_class'] = 'DrupalAPCCache';

// The 'cache_form' bin must be assigned to non-volatile storage.
$conf['cache_class_cache_form'] = 'DrupalDatabaseCache';

// Uncomment the following line to enable debugging.
// $conf['apc_show_debug'] = TRUE;

Step 3

Visit your site and verify it still works.

Step 4 (optional)

When DrupalAPCCache is used for the cache_page bin, the following lines can be added to the settings.php file used for the site.

$conf['page_cache_without_database'] = TRUE;
$conf['page_cache_invoke_hooks'] = FALSE;