2 files changed, 757 insertions, 0 deletions
diff --git a/tests/benchmarks/network/access/qnetworkreply/qnetworkreply.pro b/tests/benchmarks/network/access/qnetworkreply/qnetworkreply.pro
new file mode 100644
index 0000000000..9d96dc7025
--- /dev/null
+++ b/tests/benchmarks/network/access/qnetworkreply/qnetworkreply.pro
@@ -0,0 +1,13 @@
+load(qttest_p4)
+TEMPLATE = app
+TARGET = tst_bench_qnetworkreply
+DEPENDPATH += .
+INCLUDEPATH += .
+
+QT -= gui
+QT += network
+
+CONFIG += release
+
+# Input
+SOURCES += tst_qnetworkreply.cpp
diff --git a/tests/benchmarks/network/access/qnetworkreply/tst_qnetworkreply.cpp b/tests/benchmarks/network/access/qnetworkreply/tst_qnetworkreply.cpp
new file mode 100644
index 0000000000..9a07aa4940
--- /dev/null
+++ b/tests/benchmarks/network/access/qnetworkreply/tst_qnetworkreply.cpp
@@ -0,0 +1,744 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+// This file contains benchmarks for QNetworkReply functions.
+
+#include <QDebug>
+#include <qtest.h>
+#include <QtTest/QtTest>
+#include <QtNetwork/qnetworkreply.h>
+#include <QtNetwork/qnetworkrequest.h>
+#include <QtNetwork/qnetworkaccessmanager.h>
+#include <QtNetwork/qtcpsocket.h>
+#include <QtNetwork/qtcpserver.h>
+#include "../../../../auto/network-settings.h"
+
+
+Q_DECLARE_METATYPE(QSharedPointer<char>)
+
+class TimedSender: public QThread
+{
+    Q_OBJECT
+    qint64 totalBytes;
+    QSemaphore ready;
+    QByteArray dataToSend;
+    QTcpSocket *client;
+    int timeout;
+    int port;
+public:
+    int transferRate;
+    TimedSender(int ms)
+        : totalBytes(0), timeout(ms), port(-1), transferRate(-1)
+    {
+        dataToSend = QByteArray(16*1024, '@');
+        start();
+        ready.acquire();
+    }
+
+    inline int serverPort() const { return port; }
+
+private slots:
+    void writeMore()
+    {
+        while (client->bytesToWrite() < 128 * 1024) {
+            writePacket(dataToSend);
+        }
+    }
+
+protected:
+    void run()
+    {
+        QTcpServer server;
+        server.listen();
+        port = server.serverPort();
+        ready.release();
+
+        server.waitForNewConnection(-1);
+        client = server.nextPendingConnection();
+
+        writeMore();
+        connect(client, SIGNAL(bytesWritten(qint64)), SLOT(writeMore()), Qt::DirectConnection);
+
+        QEventLoop eventLoop;
+        QTimer::singleShot(timeout, &eventLoop, SLOT(quit()));
+
+        QTime timer;
+        timer.start();
+        eventLoop.exec();
+        disconnect(client, SIGNAL(bytesWritten(qint64)), this, 0);
+
+        // wait for the connection to shut down
+        client->disconnectFromHost();
+        if (!client->waitForDisconnected(10000))
+            return;
+
+        transferRate = totalBytes * 1000 / timer.elapsed();
+        qDebug() << "TimedSender::run" << "receive rate:" << (transferRate / 1024) << "kB/s in"
+                 << timer.elapsed() << "ms";
+    }
+
+    void writePacket(const QByteArray &array)
+    {
+        client->write(array);
+        totalBytes += array.size();
+    }
+};
+
+
+class QNetworkReplyPtr: public QSharedPointer<QNetworkReply>
+{
+public:
+    inline QNetworkReplyPtr(QNetworkReply *ptr = 0)
+        : QSharedPointer<QNetworkReply>(ptr)
+    { }
+
+    inline operator QNetworkReply *() const { return data(); }
+};
+
+
+class DataReader: public QObject
+{
+    Q_OBJECT
+public:
+    qint64 totalBytes;
+    QByteArray data;
+    QIODevice *device;
+    bool accumulate;
+    DataReader(QIODevice *dev, bool acc = true) : totalBytes(0), device(dev), accumulate(acc)
+    {
+        connect(device, SIGNAL(readyRead()), SLOT(doRead()));
+    }
+
+public slots:
+    void doRead()
+    {
+        QByteArray buffer;
+        buffer.resize(device->bytesAvailable());
+        qint64 bytesRead = device->read(buffer.data(), device->bytesAvailable());
+        if (bytesRead == -1) {
+            QTestEventLoop::instance().exitLoop();
+            return;
+        }
+        buffer.truncate(bytesRead);
+        totalBytes += bytesRead;
+
+        if (accumulate)
+            data += buffer;
+    }
+};
+
+class ThreadedDataReader: public QThread
+{
+    Q_OBJECT
+    // used to make the constructor only return after the tcp server started listening
+    QSemaphore ready;
+    QTcpSocket *client;
+    int timeout;
+    int port;
+public:
+    qint64 transferRate;
+    ThreadedDataReader()
+        : port(-1), transferRate(-1)
+    {
+        start();
+        ready.acquire();
+    }
+
+    inline int serverPort() const { return port; }
+
+protected:
+    void run()
+    {
+        QTcpServer server;
+        server.listen();
+        port = server.serverPort();
+        ready.release();
+
+        server.waitForNewConnection(-1);
+        client = server.nextPendingConnection();
+
+        QEventLoop eventLoop;
+        DataReader reader(client, false);
+        QObject::connect(client, SIGNAL(disconnected()), &eventLoop, SLOT(quit()));
+
+        QTime timer;
+        timer.start();
+        eventLoop.exec();
+        qint64 elapsed = timer.elapsed();
+
+        transferRate = reader.totalBytes * 1000 / elapsed;
+        qDebug() << "ThreadedDataReader::run" << "send rate:" << (transferRate / 1024) << "kB/s in" << elapsed << "msec";
+    }
+};
+
+class DataGenerator: public QIODevice
+{
+    Q_OBJECT
+    enum { Idle, Started, Stopped } state;
+public:
+    DataGenerator() : state(Idle)
+    { open(ReadOnly); }
+
+    virtual bool isSequential() const { return true; }
+    virtual qint64 bytesAvailable() const { return state == Started ? 1024*1024 : 0; }
+
+public slots:
+    void start() { state = Started; emit readyRead(); }
+    void stop() { state = Stopped; emit readyRead(); }
+
+protected:
+    virtual qint64 readData(char *data, qint64 maxlen)
+    {
+        if (state == Stopped)
+            return -1;          // EOF
+
+        // return as many bytes as are wanted
+        memset(data, '@', maxlen);
+        return maxlen;
+    }
+    virtual qint64 writeData(const char *, qint64)
+    { return -1; }
+};
+
+class ThreadedDataReaderHttpServer: public QThread
+{
+    Q_OBJECT
+    // used to make the constructor only return after the tcp server started listening
+    QSemaphore ready;
+    QTcpSocket *client;
+    int timeout;
+    int port;
+public:
+    qint64 transferRate;
+    ThreadedDataReaderHttpServer()
+        : port(-1), transferRate(-1)
+    {
+        start();
+        ready.acquire();
+    }
+
+    inline int serverPort() const { return port; }
+
+protected:
+    void run()
+    {
+        QTcpServer server;
+        server.listen();
+        port = server.serverPort();
+        ready.release();
+
+        QVERIFY(server.waitForNewConnection(10*1000));
+        client = server.nextPendingConnection();
+
+        // read lines until we read the empty line seperating HTTP request from HTTP request body
+        do {
+            if (client->canReadLine()) {
+                QString line = client->readLine();
+                if (line == "\n" || line == "\r\n")
+                    break; // empty line
+            }
+            if (!client->waitForReadyRead(10*1000)) {
+                client->close();
+                return;
+            }
+        } while (client->state() == QAbstractSocket::ConnectedState);
+
+        client->write("HTTP/1.0 200 OK\r\n");
+        client->write("Content-length: 0\r\n");
+        client->write("\r\n");
+        client->flush();
+
+        QCoreApplication::processEvents();
+
+        QEventLoop eventLoop;
+        DataReader reader(client, false);
+        QObject::connect(client, SIGNAL(disconnected()), &eventLoop, SLOT(quit()));
+
+        QTime timer;
+        timer.start();
+        eventLoop.exec();
+        qint64 elapsed = timer.elapsed();
+
+        transferRate = reader.totalBytes * 1000 / elapsed;
+        qDebug() << "ThreadedDataReaderHttpServer::run" << "send rate:" << (transferRate / 1024) << "kB/s in" << elapsed << "msec";
+    }
+};
+
+
+class FixedSizeDataGenerator : public QIODevice
+{
+    Q_OBJECT
+    enum { Idle, Started, Stopped } state;
+public:
+    FixedSizeDataGenerator(qint64 size) : state(Idle)
+    { open(ReadOnly | Unbuffered);
+      toBeGeneratedTotalCount = toBeGeneratedCount = size;
+    }
+
+    virtual qint64 bytesAvailable() const
+    {
+        return state == Started ? toBeGeneratedCount + QIODevice::bytesAvailable() : 0;
+    }
+
+    virtual bool isSequential() const{
+        return false;
+    }
+
+    virtual bool reset() const{
+        return false;
+    }
+
+    qint64 size() const {
+        return toBeGeneratedTotalCount;
+    }
+
+public slots:
+    void start() { state = Started; emit readyRead(); }
+
+protected:
+    virtual qint64 readData(char *data, qint64 maxlen)
+    {
+        memset(data, '@', maxlen);
+
+        if (toBeGeneratedCount <= 0) {
+            return -1;
+        }
+
+        qint64 n = qMin(maxlen, toBeGeneratedCount);
+        toBeGeneratedCount -= n;
+
+        if (toBeGeneratedCount <= 0) {
+            // make sure this is a queued connection!
+            emit readChannelFinished();
+        }
+
+        return n;
+    }
+    virtual qint64 writeData(const char *, qint64)
+    { return -1; }
+
+    qint64 toBeGeneratedCount;
+    qint64 toBeGeneratedTotalCount;
+};
+
+class HttpDownloadPerformanceServer : QObject {
+    Q_OBJECT;
+    qint64 dataSize;
+    qint64 dataSent;
+    QTcpServer server;
+    QTcpSocket *client;
+    bool serverSendsContentLength;
+    bool chunkedEncoding;
+
+public:
+    HttpDownloadPerformanceServer (qint64 ds, bool sscl, bool ce) : dataSize(ds), dataSent(0),
+    client(0), serverSendsContentLength(sscl), chunkedEncoding(ce) {
+        server.listen();
+        connect(&server, SIGNAL(newConnection()), this, SLOT(newConnectionSlot()));
+    }
+
+    int serverPort() {
+        return server.serverPort();
+    }
+
+public slots:
+
+    void newConnectionSlot() {
+        client = server.nextPendingConnection();
+        client->setParent(this);
+        connect(client, SIGNAL(readyRead()), this, SLOT(readyReadSlot()));
+        connect(client, SIGNAL(bytesWritten(qint64)), this, SLOT(bytesWrittenSlot(qint64)));
+    }
+
+    void readyReadSlot() {
+        client->readAll();
+        client->write("HTTP/1.0 200 OK\n");
+        if (serverSendsContentLength)
+            client->write(QString("Content-Length: " + QString::number(dataSize) + "\n").toAscii());
+        if (chunkedEncoding)
+            client->write(QString("Transfer-Encoding: chunked\n").toAscii());
+        client->write("Connection: close\n\n");
+    }
+
+    void bytesWrittenSlot(qint64 amount) {
+        Q_UNUSED(amount);
+        if (dataSent == dataSize && client) {
+            // close eventually
+
+            // chunked encoding: we have to send a last "empty" chunk
+            if (chunkedEncoding)
+                client->write(QString("0\r\n\r\n").toAscii());
+
+            client->disconnectFromHost();
+            server.close();
+            client = 0;
+            return;
+        }
+
+        // send data
+        if (client && client->bytesToWrite() < 100*1024 && dataSent < dataSize) {
+            qint64 amount = qMin(qint64(16*1024), dataSize - dataSent);
+            QByteArray data(amount, '@');
+
+            if (chunkedEncoding) {
+                client->write(QString(QString("%1").arg(amount,0,16).toUpper() + "\r\n").toAscii());
+                client->write(data.constData(), amount);
+                client->write(QString("\r\n").toAscii());
+            } else {
+                client->write(data.constData(), amount);
+            }
+
+            dataSent += amount;
+        }
+    }
+};
+
+class HttpDownloadPerformanceClient : QObject {
+    Q_OBJECT;
+    QIODevice *device;
+    public:
+    HttpDownloadPerformanceClient (QIODevice *dev) : device(dev){
+        connect(dev, SIGNAL(readyRead()), this, SLOT(readyReadSlot()));
+    }
+
+    public slots:
+    void readyReadSlot() {
+        device->readAll();
+    }
+
+};
+
+
+
+
+class tst_qnetworkreply : public QObject
+{
+    Q_OBJECT
+
+    QNetworkAccessManager manager;
+private slots:
+    void httpLatency();
+
+#ifndef QT_NO_OPENSSL
+    void echoPerformance_data();
+    void echoPerformance();
+#endif
+
+    void downloadPerformance();
+    void uploadPerformance();
+    void performanceControlRate();
+    void httpUploadPerformance();
+    void httpDownloadPerformance_data();
+    void httpDownloadPerformance();
+    void httpDownloadPerformanceDownloadBuffer_data();
+    void httpDownloadPerformanceDownloadBuffer();
+};
+
+void tst_qnetworkreply::httpLatency()
+{
+    QNetworkAccessManager manager;
+    QBENCHMARK{
+        QNetworkRequest request(QUrl("http://" + QtNetworkSettings::serverName() + "/qtest/"));
+        QNetworkReply* reply = manager.get(request);
+        connect(reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()), Qt::QueuedConnection);
+        QTestEventLoop::instance().enterLoop(5);
+        QVERIFY(!QTestEventLoop::instance().timeout());
+        delete reply;
+    }
+}
+
+#ifndef QT_NO_OPENSSL
+void tst_qnetworkreply::echoPerformance_data()
+{
+     QTest::addColumn<bool>("ssl");
+     QTest::newRow("no_ssl") << false;
+     QTest::newRow("ssl") << true;
+}
+
+void tst_qnetworkreply::echoPerformance()
+{
+    QFETCH(bool, ssl);
+    QNetworkAccessManager manager;
+    QNetworkRequest request(QUrl((ssl ? "https://" : "http://") + QtNetworkSettings::serverName() + "/qtest/cgi-bin/echo.cgi"));
+
+    QByteArray data;
+    data.resize(1024*1024*10); // 10 MB
+    // init with garbage. needed so ssl cannot compress it in an efficient way.
+    for (int i = 0; i < data.size() / sizeof(int); i++) {
+        int r = qrand();
+        data.data()[i*sizeof(int)] = r;
+    }
+
+    QBENCHMARK{
+        QNetworkReply* reply = manager.post(request, data);
+        connect(reply, SIGNAL(sslErrors( const QList<QSslError> &)), reply, SLOT(ignoreSslErrors()));
+        connect(reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()), Qt::QueuedConnection);
+        QTestEventLoop::instance().enterLoop(5);
+        QVERIFY(!QTestEventLoop::instance().timeout());
+        QVERIFY(reply->error() == QNetworkReply::NoError);
+        delete reply;
+    }
+}
+#endif
+
+void tst_qnetworkreply::downloadPerformance()
+{
+    // unlike the above function, this one tries to send as fast as possible
+    // and measures how fast it was.
+    TimedSender sender(5000);
+    QNetworkRequest request("debugpipe://127.0.0.1:" + QString::number(sender.serverPort()) + "/?bare=1");
+    QNetworkReplyPtr reply = manager.get(request);
+    DataReader reader(reply, false);
+
+    QTime loopTime;
+    connect(reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()));
+    loopTime.start();
+    QTestEventLoop::instance().enterLoop(40);
+    int elapsedTime = loopTime.elapsed();
+    sender.wait();
+
+    qint64 receivedBytes = reader.totalBytes;
+    qDebug() << "tst_QNetworkReply::downloadPerformance" << "receive rate:" << (receivedBytes * 1000 / elapsedTime / 1024) << "kB/s and"
+             << elapsedTime << "ms";
+}
+
+void tst_qnetworkreply::uploadPerformance()
+{
+      ThreadedDataReader reader;
+      DataGenerator generator;
+
+
+      QNetworkRequest request("debugpipe://127.0.0.1:" + QString::number(reader.serverPort()) + "/?bare=1");
+      QNetworkReplyPtr reply = manager.put(request, &generator);
+      generator.start();
+      connect(&reader, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()));
+      QTimer::singleShot(5000, &generator, SLOT(stop()));
+
+      QTestEventLoop::instance().enterLoop(30);
+      QCOMPARE(reply->error(), QNetworkReply::NoError);
+      QVERIFY(!QTestEventLoop::instance().timeout());
+}
+
+void tst_qnetworkreply::httpUploadPerformance()
+{
+#if defined(Q_OS_SYMBIAN) || defined(Q_WS_WINCE_WM)
+      // SHow some mercy for non-desktop platform/s
+      enum {UploadSize = 4*1024*1024}; // 4 MB
+#else
+      enum {UploadSize = 128*1024*1024}; // 128 MB
+#endif
+      ThreadedDataReaderHttpServer reader;
+      FixedSizeDataGenerator generator(UploadSize);
+
+      QNetworkRequest request(QUrl("http://127.0.0.1:" + QString::number(reader.serverPort()) + "/?bare=1"));
+      request.setHeader(QNetworkRequest::ContentLengthHeader,UploadSize);
+
+      QNetworkReplyPtr reply = manager.put(request, &generator);
+
+      connect(reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()));
+
+      QTime time;
+      generator.start();
+      time.start();
+      QTestEventLoop::instance().enterLoop(40);
+      qint64 elapsed = time.elapsed();
+      reader.exit();
+      reader.wait();
+      QVERIFY(reply->isFinished());
+      QCOMPARE(reply->error(), QNetworkReply::NoError);
+      QVERIFY(!QTestEventLoop::instance().timeout());
+
+      qDebug() << "tst_QNetworkReply::httpUploadPerformance" << elapsed << "msec, "
+              << ((UploadSize/1024.0)/(elapsed/1000.0)) << " kB/sec";
+}
+
+
+void tst_qnetworkreply::performanceControlRate()
+{
+    // this is a control comparison for the other two above
+    // it does the same thing, but instead bypasses the QNetworkAccess system
+    qDebug() << "The following are the maximum transfer rates that we can get in this system"
+        " (bypassing QNetworkAccess)";
+
+    TimedSender sender(5000);
+    QTcpSocket sink;
+    sink.connectToHost("127.0.0.1", sender.serverPort());
+    DataReader reader(&sink, false);
+
+    QTime loopTime;
+    connect(&sink, SIGNAL(disconnected()), &QTestEventLoop::instance(), SLOT(exitLoop()));
+    loopTime.start();
+    QTestEventLoop::instance().enterLoop(40);
+    int elapsedTime = loopTime.elapsed();
+    sender.wait();
+
+    qint64 receivedBytes = reader.totalBytes;
+    qDebug() << "tst_QNetworkReply::performanceControlRate" << "receive rate:" << (receivedBytes * 1000 / elapsedTime / 1024) << "kB/s and"
+             << elapsedTime << "ms";
+}
+
+void tst_qnetworkreply::httpDownloadPerformance_data()
+{
+    QTest::addColumn<bool>("serverSendsContentLength");
+    QTest::addColumn<bool>("chunkedEncoding");
+
+    QTest::newRow("Server sends no Content-Length") << false << false;
+    QTest::newRow("Server sends Content-Length")     << true << false;
+    QTest::newRow("Server uses chunked encoding")     << false << true;
+
+}
+
+void tst_qnetworkreply::httpDownloadPerformance()
+{
+    QFETCH(bool, serverSendsContentLength);
+    QFETCH(bool, chunkedEncoding);
+#if defined(Q_OS_SYMBIAN) || defined(Q_WS_WINCE_WM)
+    // Show some mercy to non-desktop platform/s
+    enum {UploadSize = 4*1024*1024}; // 4 MB
+#else
+    enum {UploadSize = 128*1024*1024}; // 128 MB
+#endif
+    HttpDownloadPerformanceServer server(UploadSize, serverSendsContentLength, chunkedEncoding);
+
+    QNetworkRequest request(QUrl("http://127.0.0.1:" + QString::number(server.serverPort()) + "/?bare=1"));
+    QNetworkReplyPtr reply = manager.get(request);
+
+    connect(reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()), Qt::QueuedConnection);
+    HttpDownloadPerformanceClient client(reply);
+
+    QTime time;
+    time.start();
+    QTestEventLoop::instance().enterLoop(40);
+    QCOMPARE(reply->error(), QNetworkReply::NoError);
+    QVERIFY(!QTestEventLoop::instance().timeout());
+
+    qint64 elapsed = time.elapsed();
+    qDebug() << "tst_QNetworkReply::httpDownloadPerformance" << elapsed << "msec, "
+            << ((UploadSize/1024.0)/(elapsed/1000.0)) << " kB/sec";
+};
+
+enum HttpDownloadPerformanceDownloadBufferTestType {
+    JustDownloadBuffer,
+    DownloadBufferButUseRead,
+    NoDownloadBuffer
+};
+Q_DECLARE_METATYPE(HttpDownloadPerformanceDownloadBufferTestType)
+
+class HttpDownloadPerformanceClientDownloadBuffer : QObject {
+    Q_OBJECT
+private:
+    HttpDownloadPerformanceDownloadBufferTestType testType;
+    QNetworkReply *reply;
+    qint64 uploadSize;
+    QList<qint64> bytesAvailableList;
+public:
+    HttpDownloadPerformanceClientDownloadBuffer (QNetworkReply *reply, HttpDownloadPerformanceDownloadBufferTestType testType, qint64 uploadSize)
+        : testType(testType), reply(reply), uploadSize(uploadSize)
+    {
+        connect(reply, SIGNAL(finished()), this, SLOT(finishedSlot()));
+    }
+
+    public slots:
+    void finishedSlot() {
+        if (testType == JustDownloadBuffer) {
+            // We have a download buffer and use it. This should be the fastest benchmark result.
+            QVariant downloadBufferAttribute = reply->attribute(QNetworkRequest::DownloadBufferAttribute);
+            QSharedPointer<char> data = downloadBufferAttribute.value<QSharedPointer<char> >();
+        } else if (testType == DownloadBufferButUseRead) {
+            // We had a download buffer but we benchmark here the "legacy" read() way to access it
+            char* replyData = (char*) qMalloc(uploadSize);
+            QVERIFY(reply->read(replyData, uploadSize) == uploadSize);
+            qFree(replyData);
+        } else if (testType == NoDownloadBuffer) {
+            // We did not have a download buffer but we still need to benchmark having the data, e.g. reading it all.
+            // This should be the slowest benchmark result.
+            char* replyData = (char*) qMalloc(uploadSize);
+            QVERIFY(reply->read(replyData, uploadSize) == uploadSize);
+            qFree(replyData);
+        }
+
+        QMetaObject::invokeMethod(&QTestEventLoop::instance(), "exitLoop", Qt::QueuedConnection);
+    }
+};
+
+void tst_qnetworkreply::httpDownloadPerformanceDownloadBuffer_data()
+{
+    QTest::addColumn<HttpDownloadPerformanceDownloadBufferTestType>("testType");
+
+    QTest::newRow("use-download-buffer") << JustDownloadBuffer;
+    QTest::newRow("use-download-buffer-but-use-read") << DownloadBufferButUseRead;
+    QTest::newRow("do-not-use-download-buffer") << NoDownloadBuffer;
+}
+
+// Please note that the whole "zero copy" download buffer API is private right now. Do not use it.
+void tst_qnetworkreply::httpDownloadPerformanceDownloadBuffer()
+{
+    QFETCH(HttpDownloadPerformanceDownloadBufferTestType, testType);
+
+    // On my Linux Desktop the results are already visible with 128 kB, however we use this to have good results.
+#if defined(Q_OS_SYMBIAN) || defined(Q_WS_WINCE_WM)
+    // Show some mercy to non-desktop platform/s
+    enum {UploadSize = 4*1024*1024}; // 4 MB
+#else
+    enum {UploadSize = 32*1024*1024}; // 32 MB
+#endif
+
+    HttpDownloadPerformanceServer server(UploadSize, true, false);
+
+    QNetworkRequest request(QUrl("http://127.0.0.1:" + QString::number(server.serverPort()) + "/?bare=1"));
+    if (testType == JustDownloadBuffer || testType == DownloadBufferButUseRead)
+        request.setAttribute(QNetworkRequest::MaximumDownloadBufferSizeAttribute, 1024*1024*128); // 128 MB is max allowed
+
+    QNetworkAccessManager manager;
+    QNetworkReplyPtr reply = manager.get(request);
+
+    HttpDownloadPerformanceClientDownloadBuffer client(reply, testType, UploadSize);
+
+    QBENCHMARK_ONCE {
+        QTestEventLoop::instance().enterLoop(40);
+        QCOMPARE(reply->error(), QNetworkReply::NoError);
+        QVERIFY(reply->isFinished());
+        QVERIFY(!QTestEventLoop::instance().timeout());
+    }
+}
+
+QTEST_MAIN(tst_qnetworkreply)
+
+#include "tst_qnetworkreply.moc"