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POQTcpSocket / QTcpServer memory management / server crash
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copied!<p>I am designing and making a server that should be able to handle about 100+ hits per second. The information I am getting from the server is just the HTTP header. Based on the information from the header, it will query a database(different thread) for some information and send the final information back to the QTcpServer which create an output string, and send back a HTTP Response. I am having a big problem with this that I cannot debug. My code look similar to this:</p> <pre><code>TCPInterface::TCPInterface(QObject *parent): QTcpServer(parent) { //start listening for tcp traffic on port 80 listen(QHostAddress::Any, 80); connect(this,SIGNAL(sendInfo(QTcpSocket*, QString *)), databaseThread, SLOT(recieveInfo(QTcpSocket*, QString*))); connect(databaseThread, SIGNAL(sendToTCPSend(QTcpSocket *, QString *)), this, SLOT(TCPSend(QTcpSocket*, QString*))); } </code></pre> <p>`</p> <pre><code>void TCPInterface::incomingConnection(int socket) { QTcpSocket *s = new QTcpSocket(this); connect(s, SIGNAL(readyRead()), this, SLOT(readClient())); //connect(s, SIGNAL(disconnected()), this, SLOT(discardClient())); s->setSocketDescriptor(socket); } </code></pre> <p>`</p> <pre><code>//void TCPInterface::discardClient() //{ //QTcpSocket* socket = (QTcpSocket*)sender(); //socket->deleteLater(); //} </code></pre> <p>`</p> <pre><code>void TCPInterface::readClient() { QTcpSocket* socket = (QTcpSocket*)sender(); QString header; while(socket->canReadLine()) { header += socket->readLine(); } emit sendInfo(socket, headerInfo); } </code></pre> <p>`</p> <pre><code>void databaseThread::recieveInfo(QTcpSocket* socket, QString* headerInfo) { QString*outputInfo = getDatabaseInfo(headerInfo); emit sendToTCPSend(socket, outputInfo); } </code></pre> <p>`</p> <pre><code>void TCPInterface::TCPSend(QTcpSocket* socket, QString* outputInfo); { QString response = "HTTP/1.0 200 Ok\r\n"; response += "Content-Type: text/html; charset=\"utf-8\"\r\n"; response += "\r\n" + *outputInfo + "\n"; if(socket->isWritable() && socket->isOpen()) { socket->write(response.toAscii()); } //socket->disconnectFromHost(); socket->close(); delete headerInfo; } </code></pre> <p>I having one main problem which I have an idea what it is, but cannot find a solution to fix it.</p> <p>My problem is my memory is constantly increasing as I get more hits. I am sure the cause of this is my QTcpSockets are never being deleted, since I am just closing them. However when I don't use close, and use disconnectFromHost and disconnected/discardClient slot/signal my server will crash with heavy traffic(no message or anything so I am not sure of the exact reason of the crash). Has anyone run into this problem before? Any ideas at all.</p>

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