gatewayworker每次重启，client_id都是从固定的1开始

/**
 * 生成connection id
 * @return int
 */
protected function generateConnectionId()
{
    $max_unsigned_int = 4294967295;
    if (self::$_connectionIdRecorder >= $max_unsigned_int) {
        self::$_connectionIdRecorder = 0;
    }
    while(++self::$_connectionIdRecorder <= $max_unsigned_int) {
        if(!isset($this->_clientConnections[self::$_connectionIdRecorder])) {
            break;
        }
    }
    return self::$_connectionIdRecorder;
}