public function getCacheService()
    {
        $memcached = $this->memcached;
        if (empty($memcached)) {
            /**
             * @var \Zend\Cache\Storage\Adapter\Memcached $memcached
             */
            $memcached = $this->getServiceLocator()->get('memcached');
        }

        return $memcached;
    }