ChannelClient::publish频繁出现推送不成功情况!

知道长连接需要加心跳来维持连接

读源代码发现Channel\Client有自动ping机制，这个ping也是向服务端发送信息的，可以当作是发送心跳数据吗？

既然是发送了心跳，为何出现Channel\Client::publish()失败的情况？

    public static function connect($ip = '127.0.0.1', $port = 2206)
    {
        if (self::$_remoteConnection) {
            return;
        }

        self::$_remoteIp = $ip;
        self::$_remotePort = $port;

        if (PHP_SAPI !== 'cli' || !class_exists('Workerman\Worker', false)) {
            self::$_isWorkermanEnv = false;
        }

        // For workerman environment.
        if (self::$_isWorkermanEnv) {
            if (strpos($ip, 'unix://') === false) {
                $conn = new AsyncTcpConnection('frame://' . self::$_remoteIp . ':' . self::$_remotePort);
            } else {
                $conn = new AsyncTcpConnection($ip);
                $conn->protocol = Frame::class;
            }

            $conn->onClose = [self::class, 'onRemoteClose'];
            $conn->onConnect = [self::class, 'onRemoteConnect'];
            $conn->onMessage = [self::class , 'onRemoteMessage'];
            $conn->connect();

            //自动定时发送ping

            if (empty(self::$_pingTimer)) {
                self::$_pingTimer = Timer::add(self::$pingInterval, 'Channel\Client::ping');
            }
            // Not workerman environment.
        } else {
        ......
        }

        self::$_remoteConnection = $conn;
    }

    /**
     * Ping.
     * @return void
     */
    public static function ping()
    {
        if(self::$_remoteConnection)
        {
            self::$_remoteConnection->send('');
        }
    }