QThread count in Qt applications.

[hashimov]

Ok, i will change my code for one thread and will test how behaves in this case my program, after testing i will write my results here)

What is benefit of Threaded Fortune Server Example as mentioned in Qt Examples and demos???

[wysota]

What is benefit of Threaded Fortune Server Example as mentioned in Qt Examples and demos???

Benefit over what? Over not having it that example at all? Or do you mean something different.

Please don't reply to your own posts, edit your original posts instead.

[hashimov]

I change my code for one thread for serving all tcpsocket. And the result was no effective. because when sockets count increases the waiting packages also increases, and the bad think that it concatenates the packages which comes from the same socket, for example the socket every 1 second sends "Socket", in this case in my database inserts "SocketSocket", some times many times "SocketSocket....Socket". And CPU works in 99%. But in multi thread version CPU works 1-2%.

[wysota]

I change my code for one thread for serving all tcpsocket. And the result was no effective. because when sockets count increases the waiting packages also increases, and the bad think that it concatenates the packages which comes from the same socket, for example the socket every 1 second sends "Socket", in this case in my database inserts "SocketSocket", some times many times "SocketSocket....Socket". And CPU works in 99%. But in multi thread version CPU works 1-2%.

My assumption is that you simply didn't do it correctly.

[hashimov]

// #include "gpstcpserver.h"
 
#ifndef GPSTCPSERVER_H
#define GPSTCPSERVER_H
 
#include <QtCore/QObject>
#include <QtNetwork/QTcpServer>
#include <QtNetwork/QTcpSocket>
#include "gpstcpsocket.h"
 
class GpsTcpServer : public QTcpServer
{
public:
    explicit GpsTcpServer(QObject * parent = 0);
 
    virtual void incomingConnection ( int socketDescriptor );
 
    int _count;
};
 
#endif

// #include "gpstcpserver.h"

#ifndef GPSTCPSERVER_H
#define GPSTCPSERVER_H

#include <QtCore/QObject>
#include <QtNetwork/QTcpServer>
#include <QtNetwork/QTcpSocket>
#include "gpstcpsocket.h"

class GpsTcpServer : public QTcpServer
{
public:
    explicit GpsTcpServer(QObject * parent = 0);

    virtual void incomingConnection ( int socketDescriptor );

    int _count;
};

#endif

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// gpstcpserver.cpp
 
#include "gpstcpserver.h"
 
GpsTcpServer::GpsTcpServer(QObject *parent)
    : QTcpServer(parent), _count(0)
{
}
 
void GpsTcpServer::incomingConnection(int socketDescriptor)
{
    GpsTcpSocket * socket = new GpsTcpSocket(++_count, this);
 
    if (!socket->setSocketDescriptor(socketDescriptor)){
        delete socket;
    }
}

// gpstcpserver.cpp

#include "gpstcpserver.h"

GpsTcpServer::GpsTcpServer(QObject *parent)
    : QTcpServer(parent), _count(0)
{
}

void GpsTcpServer::incomingConnection(int socketDescriptor)
{
    GpsTcpSocket * socket = new GpsTcpSocket(++_count, this);

    if (!socket->setSocketDescriptor(socketDescriptor)){
        delete socket;
    }
}

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// gpstcpsocket.h
 
#ifndef GPSTCPSOCKET_H
#define GPSTCPSOCKET_H
 
#include <QtCore/QObject>
#include <QtNetwork/QAbstractSocket>
#include <QtNetwork/QTcpSocket>
 
class GpsTcpSocket : public QTcpSocket
{
    Q_OBJECT
public:
    GpsTcpSocket(long id, QObject *parent = 0);
 
private:
    long _id;
 
signals:
 
public slots:
    void gpsReadReady();
    void gpsConnected();
    void gpsDisconnected();
    void gpsError( QAbstractSocket::SocketError socketError );
 
};
 
#endif // GPSTCPSOCKET_H

// gpstcpsocket.h

#ifndef GPSTCPSOCKET_H
#define GPSTCPSOCKET_H

#include <QtCore/QObject>
#include <QtNetwork/QAbstractSocket>
#include <QtNetwork/QTcpSocket>

class GpsTcpSocket : public QTcpSocket
{
    Q_OBJECT
public:
    GpsTcpSocket(long id, QObject *parent = 0);

private:
    long _id;

signals:

public slots:
    void gpsReadReady();
    void gpsConnected();
    void gpsDisconnected();
    void gpsError( QAbstractSocket::SocketError socketError );

};

#endif // GPSTCPSOCKET_H

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// gpstcpsocket.cpp
 
#include "gpstcpsocket.h"
 
#include <QtCore/QFile>
 
GpsTcpSocket::GpsTcpSocket(long id, QObject *parent) :
    QTcpSocket(parent), _id(id)
{
    connect(this, SIGNAL(readyRead()), this, SLOT(gpsReadReady()));
    connect(this, SIGNAL(connected()), this, SLOT(gpsConnected()));
    connect(this, SIGNAL(disconnected()), this, SLOT(gpsDisconnected()));
    connect(this, SIGNAL(error(QAbstractSocket::SocketError)), this, SLOT(gpsError(QAbstractSocket::SocketError)));
}
 
void GpsTcpSocket::gpsReadReady()
{
    int availableBytes = bytesAvailable();
 
    char * data = new char[availableBytes];
    read(data, availableBytes);
 
    /*QFile file("c:/data.txt");
    file.open(QFile::Append);
    file.write(data, availableBytes);
    file.close();*/
 
    delete [] data;
}
 
void GpsTcpSocket::gpsConnected()
{
}
 
void GpsTcpSocket::gpsDisconnected()
{
}
 
void GpsTcpSocket::gpsError(QAbstractSocket::SocketError socketError)
{
    Q_UNUSED(socketError);
}

// gpstcpsocket.cpp

#include "gpstcpsocket.h"

#include <QtCore/QFile>

GpsTcpSocket::GpsTcpSocket(long id, QObject *parent) :
    QTcpSocket(parent), _id(id)
{
    connect(this, SIGNAL(readyRead()), this, SLOT(gpsReadReady()));
    connect(this, SIGNAL(connected()), this, SLOT(gpsConnected()));
    connect(this, SIGNAL(disconnected()), this, SLOT(gpsDisconnected()));
    connect(this, SIGNAL(error(QAbstractSocket::SocketError)), this, SLOT(gpsError(QAbstractSocket::SocketError)));
}

void GpsTcpSocket::gpsReadReady()
{
    int availableBytes = bytesAvailable();

    char * data = new char[availableBytes];
    read(data, availableBytes);

    /*QFile file("c:/data.txt");
    file.open(QFile::Append);
    file.write(data, availableBytes);
    file.close();*/

    delete [] data;
}

void GpsTcpSocket::gpsConnected()
{
}

void GpsTcpSocket::gpsDisconnected()
{
}

void GpsTcpSocket::gpsError(QAbstractSocket::SocketError socketError)
{
    Q_UNUSED(socketError);
}

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// main.cpp
 
#include <QtCore/QCoreApplication>
#include <QtNetwork/QHostAddress>
#include "gpstcpserver.h"
 
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
 
    GpsTcpServer server;
    server.listen(QHostAddress::Any, 1000);
 
    return a.exec();
}

// main.cpp

#include <QtCore/QCoreApplication>
#include <QtNetwork/QHostAddress>
#include "gpstcpserver.h"

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

    GpsTcpServer server;
    server.listen(QHostAddress::Any, 1000);

    return a.exec();
}

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[wysota]

Please do not inline large amount of code in your posts or at least use proper bbcode tags.

By the way, is this code supposed to prove anything?

[hashimov]

wysota, i posted my code, what is incorrect?

[wysota]

It's correct but it doesn't do anything. The only thing I see incorrect (but only because of knowing what "issues" you experience) is that you read all the data each and every time and that's why you get "SocketSocket" instead of two "Socket" reads. It's because you probably don't understand (or just forgot about it) that TCP is a stream of bytes and is not record-based. The fact that on the sending side you write two "Socket" words separately won't cause the receiving end to read two datagrams containing one "Socket" entry each. And you get 99% of the CPU usage probably because you are dumping the contents of the sockets to the console which is terribly time consuming.

[tbscope]

Some inspiration:
http://www.qtcentre.org/wiki/index.p...hout_threading