public function read($key)
{
$this->_track('read');
DebugTimer::start('Cache.read ' . $key);
$result = $this->_engine->read($key);
DebugTimer::stop('Cache.read ' . $key);
$metric = 'hit';
if ($result === false) {
$metric = 'miss';
}
$this->_track($metric);
return $result;
}