Memcache::flush Flush all existing items at the server &reftitle.description; boolMemcache::flush Memcache::flush immediately invalidates all existing items. Memcache::flush doesn't actually free any resources, it only marks all the items as expired, so occupied memory will be overwritten by new items. Also you can use memcache_flush function. &reftitle.returnvalues; &return.success; &reftitle.examples; connect('memcache_host', 11211); $memcache_obj->flush(); ?> ]]>