Enable use of memcache

Author: Jamie Snape

core/GlobalController.php

@@ -116,36 +116,41 @@ public function preDispatch()
     parent::preDispatch();
     if(!$this->isDebug())
       {
-      $frontendOptions = array(
-        'lifetime' => 86400,
-        'automatic_serialization' => true
-        );
-
-      $backendOptions = array(
-        'cache_dir' => UtilityComponent::getCacheDirectory().'/db'
-        );
-
-      $cache = Zend_Cache::factory('Core',
-                                   'File',
-                                   $frontendOptions,
-                                   $backendOptions);
-
-      // Passing the object to cache by default
-      Zend_Db_Table_Abstract::setDefaultMetadataCache($cache);
+      $frontendOptions = array('automatic_serialization' => true, 'lifetime' => 86400);
+      if(extension_loaded('memcache'))
+        {
+        $cache = Zend_Cache::factory('Core', 'Memcached', $frontendOptions, array());
+        }
+      else if(extension_loaded('memcached'))
+        {
+        $cache = Zend_Cache::factory('Core', 'Libmemcached', $frontendOptions, array());
+        }
+      else
+        {
+        $cacheDir = UtilityComponent::getCacheDirectory() . '/db';
+        if(is_writable($cacheDir))
+          {
+          $backendOptions = array('cache_dir' => $cacheDir);
+          $cache = Zend_Cache::factory('Core', 'File', $frontendOptions, $backendOptions);
+          }
+        }
+      if(isset($cache))
+        {
+        Zend_Db_Table_Abstract::setDefaultMetadataCache($cache);
+        }
       }
     }
 
   /**
    * Post-dispatch routines
    *
-   * Common usages for postDispatch() include rendering content in a sitewide
+   * Common usages for postDispatch() include rendering content in a site wide
    * template, link url correction, setting headers, etc.
    *
    * @return void
    */
   public function postDispatch()
     {
-
     parent::postDispatch();
     if($this->isDebug() && $this->getEnvironment() != 'testing')
       {