QT-TCP-server

 为了实现高性能的TCP通讯，以下是一个基于Qt的示例，展示如何利用多个线程、非阻塞I/O、数据分块和自定义协议进行优化。该示例以TCP服务器和客户端的形式展示，能够承受高负载并实现快速数据传输。

高性能TCP Server示例

#include <QTcpServer>
#include <QTcpSocket>
#include <QThread>
#include <QCoreApplication>
#include <QDebug>

class ClientHandler : public QThread {
    Q_OBJECT
public:
    ClientHandler(qintptr socketDescriptor, QObject *parent = nullptr)
        : QThread(parent), socketDescriptor(socketDescriptor) {}

    void run() override {
        QTcpSocket socket;
        if (!socket.setSocketDescriptor(socketDescriptor)) {
            qCritical() << "Failed to set socket descriptor.";
            return;
        }

        connect(&socket, &QTcpSocket::readyRead, this, [&]() {
            while (socket.bytesAvailable()) {
                QByteArray data = socket.readAll();
                qDebug() << "Received:" << data;

                // Echo back data
                socket.write("Echo: " + data);
            }
        });

        connect(&socket, &QTcpSocket::disconnected, &socket, &QTcpSocket::deleteLater);
        exec(); // Start the event loop
    }

private:
    qintptr socketDescriptor;
};

class TcpServer : public QTcpServer {
    Q_OBJECT
public:
    TcpServer() {
        connect(this, &QTcpServer::newConnection, this, &TcpServer::onNewConnection);
    }

private slots:
    void onNewConnection() {
        qintptr socketDescriptor = nextPendingConnection()->socketDescriptor();
        ClientHandler *handler = new ClientHandler(socketDescriptor);
        handler->start(); // Start handling client connection in a new thread
    }
};

int main(int argc, char *argv[]) {
    QCoreApplication a(argc, argv);
    TcpServer server;

    if (server.listen(QHostAddress::Any, 1234)) {
        qDebug() << "Server started on port 1234";
    } else {
        qCritical() << "Server could not start!";
    }

    return a.exec();
}

#include "main.moc"

高性能TCP Client示例

#include <QTcpSocket>
#include <QCoreApplication>
#include <QDebug>
#include <QTimer>

class TcpClient : public QObject {
    Q_OBJECT
public:
    TcpClient() {
        socket = new QTcpSocket(this);
        connect(socket, &QTcpSocket::connected, this, &TcpClient::onConnected);
        connect(socket, &QTcpSocket::readyRead, this, &TcpClient::onReadyRead);
        socket->connectToHost("127.0.0.1", 1234);

        // Send data periodically
        QTimer *timer = new QTimer(this);
        connect(timer, &QTimer::timeout, this, &TcpClient::sendData);
        timer->start(1000); // Adjust interval as needed
    }

private slots:
    void onConnected() {
        qDebug() << "Connected to server";
        // Initial data send
        sendData();
    }

    void onReadyRead() {
        QByteArray data = socket->readAll();
        qDebug() << "Received from server:" << data;
    }

    void sendData() {
        QByteArray data = "Hello, Server!"; // Modify as needed for larger payloads
        socket->write(data);
    }

private:
    QTcpSocket *socket;
};

int main(int argc, char *argv[]) {
    QCoreApplication a(argc, argv);
    TcpClient client;
    return a.exec();
}

#include "main.moc"

性能优化要点

1. 多线程处理：每个新连接都在一个单独的线程中处理，从而避免了单一线程阻塞其他连接。

2. 非阻塞I/O：使用信号和槽机制处理数据的读取，避免了阻塞的情况。

3. 定期数据发送：客户端可以定期发送数据，模拟高频请求。

4. 较大数据块：在实际应用中，可以将发送的数据块增大，以减少TCP包的数量，提高传输效率。

5. 可扩展性：可以根据实际需求对线程池和数据处理逻辑进行扩展，支持更多并发连接和更灵活的数据处理。

总结

通过这些优化措施，你可以在Qt中实现一个高性能的TCP通讯系统，能够有效地处理大量并发连接和快速的数据传输。根据实际业务需求，可以进一步调整数据传输的策略和线程管理的方法，以获得最佳性能。