public function shouldUpdate() {
		$now = microtime(true) * 1000;

		if (empty($this->_timer)) {
			$this->_start = (int)(($this->_timer = $now) / 1000);
			return true;
		}

		if (($now - $this->_timer) > $this->_interval) {
			$this->_timer = $now;
			return true;
		}
		return false;
	}