protected function x_tune_ok($channel_max, $frame_max, $heartbeat)
    {
        $args = new AMQPWriter();
        $args->write_short($channel_max);
        $args->write_long($frame_max);
        $args->write_short($heartbeat);
        $this->send_method_frame(array(10, 31), $args);
        $this->wait_tune_ok = false;
    }