diff --git a/includes/cache.inc b/includes/cache.inc
index 9b60a7e..f94ca80 100644
--- a/includes/cache.inc
+++ b/includes/cache.inc
@@ -373,9 +373,6 @@ class DrupalDatabaseCache implements DrupalCacheInterface {
 
   function getMultiple(&$cids) {
     try {
-      // Garbage collection necessary when enforcing a minimum cache lifetime.
-      $this->garbageCollection($this->bin);
-
       // When serving cached pages, the overhead of using db_select() was found
       // to add around 30% overhead to the request. Since $this->bin is a
       // variable, this means the call to db_query() here uses a concatenated
@@ -490,30 +487,28 @@ class DrupalDatabaseCache implements DrupalCacheInterface {
   }
 
   function expire() {
-    if (variable_get('cache_lifetime', 0)) {
+    if ($cache_lifetime = variable_get('cache_lifetime', 0)) {
       // We store the time in the current user's $user->cache variable which
       // will be saved into the sessions bin by _drupal_session_write(). We then
       // simulate that the cache was flushed for this user by not returning
       // cached data that was cached before the timestamp.
       $GLOBALS['user']->cache = REQUEST_TIME;
 
-      $cache_flush = variable_get('cache_flush_' . $this->bin, 0);
-      if ($cache_flush == 0) {
-        // This is the first request to clear the cache, start a timer.
-        variable_set('cache_flush_' . $this->bin, REQUEST_TIME);
-      }
-      elseif (REQUEST_TIME > ($cache_flush + variable_get('cache_lifetime', 0))) {
-        // Clear the cache for everyone, cache_lifetime seconds have
-        // passed since the first request to clear the cache.
-        db_delete($this->bin)
-          ->condition('expire', CACHE_PERMANENT, '<>')
-          ->condition('expire', REQUEST_TIME, '<')
-          ->execute();
-        variable_set('cache_flush_' . $this->bin, 0);
-      }
+      // Clear expired items from the cache.
+      db_delete($this->bin)
+        ->condition('expire', CACHE_PERMANENT, '>')
+        ->condition('expire', REQUEST_TIME, '<')
+        ->execute();
+      variable_set('cache_flush_' . $this->bin, 0);
+
+      // Clear CACHE_TEMPORARY items that are older than the minimum cache lifetime.
+      db_delete($this->bin)
+        ->condition('expire', CACHE_TEMPORARY)
+        ->condition('created', REQUEST_TIME - $cache_lifetime, '<')
+        ->execute(); 
     }
     else {
-      // No minimum cache lifetime, flush all temporary cache entries now.
+      // No minimum cache lifetime, flush all expired and temporary cache entries now.
       db_delete($this->bin)
         ->condition('expire', CACHE_PERMANENT, '<>')
         ->condition('expire', REQUEST_TIME, '<')
@@ -522,20 +517,7 @@ class DrupalDatabaseCache implements DrupalCacheInterface {
   }
 
   function garbageCollection() {
-    global $user;
-
-    // When cache lifetime is in force, avoid running garbage collection too
-    // often since this will remove temporary cache items indiscriminately.
-    $cache_flush = variable_get('cache_flush_' . $this->bin, 0);
-    if ($cache_flush && ($cache_flush + variable_get('cache_lifetime', 0) <= REQUEST_TIME)) {
-      // Reset the variable immediately to prevent a meltdown in heavy load situations.
-      variable_set('cache_flush_' . $this->bin, 0);
-      // Time to flush old cache data
-      db_delete($this->bin)
-        ->condition('expire', CACHE_PERMANENT, '<>')
-        ->condition('expire', $cache_flush, '<=')
-        ->execute();
-    }
+    $this->expire();
   }
 
   function clear($cid = NULL, $wildcard = FALSE) {
diff --git a/modules/system/system.install b/modules/system/system.install
index 5c4250a..8d4b048 100644
--- a/modules/system/system.install
+++ b/modules/system/system.install
@@ -675,7 +675,7 @@ function system_schema() {
       ),
     ),
     'indexes' => array(
-      'expire' => array('expire'),
+      'expire_created' => array('expire', 'created'),
     ),
     'primary key' => array('cid'),
   );
diff --git a/modules/system/system.module b/modules/system/system.module
index d7dc69c..fabd436 100644
--- a/modules/system/system.module
+++ b/modules/system/system.module
@@ -3007,7 +3007,22 @@ function system_cron() {
   $core = array('cache', 'path', 'filter', 'page', 'form', 'menu');
   $cache_bins = array_merge(module_invoke_all('flush_caches'), $core);
   foreach ($cache_bins as $bin) {
-    cache($bin)->expire();
+    // If the cache backend provides a garbageCollection() method, call that.
+    // If it does not, expire all temporary and expired cache items. Limit 
+    // these calls to once every 24 hours by default to avoid wiping the page
+    // and block caches every cron run.
+    $cache = cache($bin);
+    $name = 'cache_garbage_collect_' . $bin;
+    $window = max(variable_get('cache_lifetime', 0), variable_get('cache_garbage_collection_frequency', 86400));
+    if (flood_is_allowed($name, 1, $window, 'cron')) {
+      flood_register_event($name, 1, $window, 'cron');
+      if (method_exists($cache, 'garbageCollection')) {
+        $cache->garbageCollection();
+      }
+      else {
+        $cache->expire();
+      }
+    }
   }
 
   // Cleanup the batch table and the queue for failed batches.