qt 6.5.1 original

tests/benchmarks/network/access/CMakeLists.txt

@@ -0,0 +1,10 @@
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+add_subdirectory(qfile_vs_qnetworkaccessmanager)
+add_subdirectory(qnetworkreply)
+add_subdirectory(qnetworkreply_from_cache)
+add_subdirectory(qnetworkdiskcache)
+if(QT_FEATURE_private_tests)
+    add_subdirectory(qdecompresshelper)
+endif()

tests/benchmarks/network/access/qdecompresshelper/CMakeLists.txt

@@ -0,0 +1,16 @@
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+#####################################################################
+## qdecompresshelper Binary:
+#####################################################################
+
+qt_internal_add_benchmark(qdecompresshelper
+    SOURCES
+        main.cpp
+    DEFINES
+        SRC_DIR=${CMAKE_CURRENT_SOURCE_DIR}
+    LIBRARIES
+        Qt::NetworkPrivate
+        Qt::Test
+)

tests/benchmarks/network/access/qdecompresshelper/main.cpp

@@ -0,0 +1,71 @@
+// Copyright (C) 2020 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#include <QtNetwork/private/qdecompresshelper_p.h>
+
+#include <QtTest/QTest>
+
+class tst_QDecompressHelper : public QObject
+{
+    Q_OBJECT
+private slots:
+    void decompress_data();
+    void decompress();
+};
+
+void tst_QDecompressHelper::decompress_data()
+{
+    QTest::addColumn<QByteArray>("encoding");
+    QTest::addColumn<QString>("fileName");
+
+    QString srcDir = QStringLiteral(QT_STRINGIFY(SRC_DIR));
+    srcDir = QDir::fromNativeSeparators(srcDir);
+    if (!srcDir.endsWith("/"))
+        srcDir += "/";
+
+    bool dataAdded = false;
+#ifndef QT_NO_COMPRESS
+    QTest::addRow("gzip") << QByteArray("gzip") << srcDir + QString("50mb.txt.gz");
+    dataAdded = true;
+#endif
+#if QT_CONFIG(brotli)
+    QTest::addRow("brotli") << QByteArray("br") << srcDir + QString("50mb.txt.br");
+    dataAdded = true;
+#endif
+#if QT_CONFIG(zstd)
+    QTest::addRow("zstandard") << QByteArray("zstd") << srcDir + QString("50mb.txt.zst");
+    dataAdded = true;
+#endif
+    if (!dataAdded)
+        QSKIP("There's no decompression support");
+}
+
+void tst_QDecompressHelper::decompress()
+{
+    QFETCH(QByteArray, encoding);
+    QFETCH(QString, fileName);
+
+    QFile file { fileName };
+    QVERIFY(file.open(QIODevice::ReadOnly));
+    QBENCHMARK {
+        file.seek(0);
+        QDecompressHelper helper;
+        helper.setEncoding(encoding);
+        QVERIFY(helper.isValid());
+
+        helper.feed(file.readAll());
+
+        qsizetype bytes = 0;
+        while (helper.hasData()) {
+            QByteArray out(64 * 1024, Qt::Uninitialized);
+            qsizetype bytesRead = helper.read(out.data(), out.size());
+            bytes += bytesRead;
+        }
+
+        QCOMPARE(bytes, 50 * 1024 * 1024);
+    }
+}
+
+QTEST_MAIN(tst_QDecompressHelper)
+
+#include "main.moc"

tests/benchmarks/network/access/qfile_vs_qnetworkaccessmanager/CMakeLists.txt

@@ -0,0 +1,14 @@
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+#####################################################################
+## tst_bench_qfile_vs_qnetworkaccessmanager Binary:
+#####################################################################
+
+qt_internal_add_benchmark(tst_bench_qfile_vs_qnetworkaccessmanager
+    SOURCES
+        main.cpp
+    LIBRARIES
+        Qt::Network
+        Qt::Test
+)

tests/benchmarks/network/access/qfile_vs_qnetworkaccessmanager/main.cpp

@@ -0,0 +1,154 @@
+// Copyright (C) 2020 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+#include <QDebug>
+#include <qtest.h>
+#include <QTest>
+#include <QTestEventLoop>
+#include <QtNetwork/qnetworkreply.h>
+#include <QtNetwork/qnetworkrequest.h>
+#include <QtNetwork/qnetworkaccessmanager.h>
+#include <QtCore/QTemporaryFile>
+#include <QtCore/QElapsedTimer>
+#include <QtCore/QFile>
+
+class qfile_vs_qnetworkaccessmanager : public QObject
+{
+    Q_OBJECT
+protected:
+    void qnamFileRead_iteration(QNetworkAccessManager &manager, QNetworkRequest &request);
+    void qnamImmediateFileRead_iteration(QNetworkAccessManager &manager, QNetworkRequest &request);
+    void qfileFileRead_iteration();
+    static const int iterations = 10;
+
+private slots:
+    void qnamFileRead();
+    void qnamImmediateFileRead();
+    void qfileFileRead();
+
+    void initTestCase();
+    void cleanupTestCase();
+
+public:
+    qint64 size;
+    QTemporaryFile testFile;
+
+    qfile_vs_qnetworkaccessmanager() : QObject(), size(0) {};
+};
+
+void qfile_vs_qnetworkaccessmanager::initTestCase()
+{
+    testFile.open();
+    QByteArray qba(1*1024*1024, 'x'); // 1 MB
+    for (int i = 0; i < 100; i++) {
+        testFile.write(qba);
+        testFile.flush();
+        size += qba.size();
+    } // 100 MB or 10 MB
+    testFile.reset();
+}
+
+void qfile_vs_qnetworkaccessmanager::cleanupTestCase()
+{
+
+}
+
+void qfile_vs_qnetworkaccessmanager::qnamFileRead_iteration(QNetworkAccessManager &manager, QNetworkRequest &request)
+{
+    QNetworkReply* reply = manager.get(request);
+    connect(reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()), Qt::QueuedConnection);
+    QTestEventLoop::instance().enterLoop(10);
+    QVERIFY(!QTestEventLoop::instance().timeout());
+    QByteArray qba = reply->readAll();
+    delete reply;
+}
+
+void qfile_vs_qnetworkaccessmanager::qnamFileRead()
+{
+    QNetworkAccessManager manager;
+    QElapsedTimer t;
+    QNetworkRequest request(QUrl::fromLocalFile(testFile.fileName()));
+
+    // do 3 dry runs for cache warmup
+    qnamFileRead_iteration(manager, request);
+    qnamFileRead_iteration(manager, request);
+    qnamFileRead_iteration(manager, request);
+
+    t.start();
+    // 10 real runs
+    QBENCHMARK_ONCE {
+        for (int i = 0; i < iterations; i++) {
+            qnamFileRead_iteration(manager, request);
+        }
+    }
+
+    qint64 elapsed = t.elapsed();
+    qDebug() << Qt::endl << "Finished!";
+    qDebug() << "Bytes:" << size;
+    qDebug() << "Speed:" <<  (qreal(size*iterations) / 1024.0) / (qreal(elapsed) / 1000.0) << "KB/sec";
+}
+
+void qfile_vs_qnetworkaccessmanager::qnamImmediateFileRead_iteration(QNetworkAccessManager &manager, QNetworkRequest &request)
+{
+    QNetworkReply* reply = manager.get(request);
+    QVERIFY(reply->isFinished()); // should be like that!
+    QByteArray qba = reply->readAll();
+    delete reply;
+}
+
+void qfile_vs_qnetworkaccessmanager::qnamImmediateFileRead()
+{
+    QNetworkAccessManager manager;
+    QElapsedTimer t;
+    QNetworkRequest request(QUrl::fromLocalFile(testFile.fileName()));
+
+    // do 3 dry runs for cache warmup
+    qnamImmediateFileRead_iteration(manager, request);
+    qnamImmediateFileRead_iteration(manager, request);
+    qnamImmediateFileRead_iteration(manager, request);
+
+    t.start();
+    // 10 real runs
+    QBENCHMARK_ONCE {
+        for (int i = 0; i < iterations; i++) {
+            qnamImmediateFileRead_iteration(manager, request);
+        }
+    }
+
+    qint64 elapsed = t.elapsed();
+    qDebug() << Qt::endl << "Finished!";
+    qDebug() << "Bytes:" << size;
+    qDebug() << "Speed:" <<  (qreal(size*iterations) / 1024.0) / (qreal(elapsed) / 1000.0) << "KB/sec";
+}
+
+void qfile_vs_qnetworkaccessmanager::qfileFileRead_iteration()
+{
+    testFile.reset();
+    QByteArray qba = testFile.readAll();
+}
+
+void qfile_vs_qnetworkaccessmanager::qfileFileRead()
+{
+    QElapsedTimer t;
+
+    // do 3 dry runs for cache warmup
+    qfileFileRead_iteration();
+    qfileFileRead_iteration();
+    qfileFileRead_iteration();
+
+    t.start();
+    // 10 real runs
+    QBENCHMARK_ONCE {
+        for (int i = 0; i < iterations; i++) {
+            qfileFileRead_iteration();
+        }
+    }
+
+    qint64 elapsed = t.elapsed();
+    qDebug() << Qt::endl << "Finished!";
+    qDebug() << "Bytes:" << size;
+    qDebug() << "Speed:" <<  (qreal(size*iterations) / 1024.0) / (qreal(elapsed) / 1000.0) << "KB/sec";
+}
+
+QTEST_MAIN(qfile_vs_qnetworkaccessmanager)
+
+#include "main.moc"

tests/benchmarks/network/access/qnetworkdiskcache/CMakeLists.txt

@@ -0,0 +1,14 @@
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+#####################################################################
+## tst_bench_qnetworkdiskcache Binary:
+#####################################################################
+
+qt_internal_add_benchmark(tst_bench_qnetworkdiskcache
+    SOURCES
+        tst_qnetworkdiskcache.cpp
+    LIBRARIES
+        Qt::Network
+        Qt::Test
+)

tests/benchmarks/network/access/qnetworkdiskcache/tst_qnetworkdiskcache.cpp

@@ -0,0 +1,379 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#include <QNetworkDiskCache>
+#include <QNetworkCacheMetaData>
+#include <QDir>
+#include <QBuffer>
+#include <QTextStream>
+#include <QDebug>
+#include <QTest>
+#include <QIODevice>
+#include <QStandardPaths>
+#include <QDirIterator>
+
+
+
+enum Numbers { NumFakeCacheObjects   = 200,    //entries in pre-populated cache
+               NumInsertions  = 100,           //insertions to be timed
+               NumRemovals    = 100,           //removals to be timed
+               NumReadContent = 100,           //meta requests to be timed
+               HugeCacheLimit = 50*1024*1024,  // max size for a big cache
+               TinyCacheLimit = 1*512*1024}; //  max size for a tiny cache
+
+const QString fakeURLbase = "http://127.0.0.1/fake/";
+//fake HTTP body aka payload
+const QByteArray payload("Qt rocks!");
+
+class tst_qnetworkdiskcache : public QObject
+{
+    Q_OBJECT
+private:
+    void injectFakeData();
+    void insertOneItem();
+    bool isUrlCached(quint32 id);
+    void cleanRecursive(QString &path);
+    void cleanupCacheObject();
+    void initCacheObject();
+    QString cacheDir;
+    QNetworkDiskCache *cache;
+
+public slots:
+    void initTestCase();
+    void cleanupTestCase();
+
+private slots:
+
+    void timeInsertion_data();
+    void timeInsertion();
+    void timeRead_data();
+    void timeRead();
+    void timeRemoval_data();
+    void timeRemoval();
+
+    void timeExpiration_data();
+    void timeExpiration();
+};
+
+
+void tst_qnetworkdiskcache::initTestCase()
+{
+    cache = 0;
+}
+
+
+void tst_qnetworkdiskcache::cleanupTestCase()
+{
+    cleanupCacheObject();
+    cleanRecursive(cacheDir);
+}
+
+void tst_qnetworkdiskcache::timeInsertion_data()
+{
+    QTest::addColumn<QString>("cacheRootDirectory");
+
+    QString cacheLoc = QStandardPaths::writableLocation(QStandardPaths::CacheLocation);
+    QTest::newRow("QStandardPaths Cache Location") << cacheLoc;
+}
+
+//This functions times an insert() operation.
+//You can run it after populating the cache with
+//fake data so that more realistic performance
+//estimates are obtained.
+void tst_qnetworkdiskcache::timeInsertion()
+{
+
+    QFETCH(QString, cacheRootDirectory);
+
+    cacheDir = QString( cacheRootDirectory + QDir::separator() + "man_qndc");
+    QDir d;
+    qDebug() << "Setting cache directory to = " << d.absoluteFilePath(cacheDir);
+
+    //Housekeeping
+    cleanRecursive(cacheDir); // slow op.
+    initCacheObject();
+
+    cache->setCacheDirectory(cacheDir);
+    cache->setMaximumCacheSize(qint64(HugeCacheLimit));
+    cache->clear();
+
+    //populate some fake data to simulate partially full cache
+    injectFakeData(); // SLOW
+
+    //Sanity-check that the first URL that we insert below isn't already in there.
+    QVERIFY(isUrlCached(NumFakeCacheObjects) == false);
+
+    // IMPORTANT: max cache size should be HugeCacheLimit, to avoid evictions below
+    //time insertion of previously-uncached URLs.
+    QBENCHMARK_ONCE {
+        for (quint32 i = NumFakeCacheObjects; i < (NumFakeCacheObjects + NumInsertions); i++) {
+            //prepare metata for url
+            QNetworkCacheMetaData meta;
+            QString fakeURL;
+            QTextStream stream(&fakeURL);
+            stream << fakeURLbase << i;
+            QUrl url(fakeURL);
+            meta.setUrl(url);
+            meta.setSaveToDisk(true);
+
+            //commit payload and metadata to disk
+            QIODevice *device = cache->prepare(meta);
+            device->write(payload);
+            cache->insert(device);
+        }
+    }
+
+    //SLOW cleanup
+    cleanupCacheObject();
+    cleanRecursive(cacheDir);
+
+}
+
+void tst_qnetworkdiskcache::timeRead_data()
+{
+    QTest::addColumn<QString>("cacheRootDirectory");
+
+    QString cacheLoc = QStandardPaths::writableLocation(QStandardPaths::CacheLocation);
+    QTest::newRow("QStandardPaths Cache Location") << cacheLoc;
+}
+
+//Times metadata as well payload lookup
+// i.e metaData(), rawHeaders() and data()
+void tst_qnetworkdiskcache::timeRead()
+{
+
+    QFETCH(QString, cacheRootDirectory);
+
+    cacheDir = QString( cacheRootDirectory + QDir::separator() + "man_qndc");
+    QDir d;
+    qDebug() << "Setting cache directory to = " << d.absoluteFilePath(cacheDir);
+
+    //Housekeeping
+    cleanRecursive(cacheDir); // slow op.
+    initCacheObject();
+    cache->setCacheDirectory(cacheDir);
+    cache->setMaximumCacheSize(qint64(HugeCacheLimit));
+    cache->clear();
+
+    //populate some fake data to simulate partially full cache
+    injectFakeData();
+
+    //Entries in the cache should be > what we try to remove
+    QVERIFY(NumFakeCacheObjects > NumReadContent);
+
+    //time metadata lookup of previously inserted URL.
+    QBENCHMARK_ONCE {
+        for (quint32 i = 0; i < NumReadContent; i++) {
+            QString fakeURL;
+            QTextStream stream(&fakeURL);
+            stream << fakeURLbase << i;
+            QUrl url(fakeURL);
+
+            QNetworkCacheMetaData qndc = cache->metaData(url);
+            QVERIFY(qndc.isValid()); // we must have read the metadata
+
+            QNetworkCacheMetaData::RawHeaderList raw(qndc.rawHeaders());
+            QVERIFY(raw.size()); // we must have parsed the headers from the meta
+
+            QIODevice *iodevice(cache->data(url));
+            QVERIFY(iodevice);    //must not be NULL
+            iodevice->close();
+            delete iodevice;
+        }
+    }
+
+    //Cleanup (slow)
+    cleanupCacheObject();
+    cleanRecursive(cacheDir);
+
+}
+
+void tst_qnetworkdiskcache::timeRemoval_data()
+{
+    QTest::addColumn<QString>("cacheRootDirectory");
+
+    QString cacheLoc = QStandardPaths::writableLocation(QStandardPaths::CacheLocation);
+    QTest::newRow("QStandardPaths Cache Location") << cacheLoc;
+}
+
+void tst_qnetworkdiskcache::timeRemoval()
+{
+
+    QFETCH(QString, cacheRootDirectory);
+
+    cacheDir = QString( cacheRootDirectory + QDir::separator() + "man_qndc");
+    QDir d;
+    qDebug() << "Setting cache directory to = " << d.absoluteFilePath(cacheDir);
+
+    //Housekeeping
+    initCacheObject();
+    cleanRecursive(cacheDir); // slow op.
+    cache->setCacheDirectory(cacheDir);
+    // Make max cache size HUGE, so that evictions don't happen below
+    cache->setMaximumCacheSize(qint64(HugeCacheLimit));
+    cache->clear();
+
+    //populate some fake data to simulate partially full cache
+    injectFakeData();
+
+    //Sanity-check that the URL is already in there somewhere
+    QVERIFY(isUrlCached(NumRemovals-1) == true);
+    //Entries in the cache should be > what we try to remove
+    QVERIFY(NumFakeCacheObjects > NumRemovals);
+
+    //time removal of previously-inserted URL.
+    QBENCHMARK_ONCE {
+        for (quint32 i = 0; i < NumRemovals; i++) {
+            QString fakeURL;
+            QTextStream stream(&fakeURL);
+            stream << fakeURLbase << i;
+            QUrl url(fakeURL);
+            cache->remove(url);
+        }
+    }
+
+    //Cleanup (slow)
+    cleanupCacheObject();
+    cleanRecursive(cacheDir);
+
+}
+
+void tst_qnetworkdiskcache::timeExpiration_data()
+{
+    QTest::addColumn<QString>("cacheRootDirectory");
+
+    QString cacheLoc = QStandardPaths::writableLocation(QStandardPaths::CacheLocation);
+    QTest::newRow("QStandardPaths Cache Location") << cacheLoc;
+}
+
+void tst_qnetworkdiskcache::timeExpiration()
+{
+
+    QFETCH(QString, cacheRootDirectory);
+
+    cacheDir = QString( cacheRootDirectory + QDir::separator() + "man_qndc");
+    QDir d;
+    qDebug() << "Setting cache directory to = " << d.absoluteFilePath(cacheDir);
+
+    //Housekeeping
+    initCacheObject();
+    cleanRecursive(cacheDir); // slow op.
+    cache->setCacheDirectory(cacheDir);
+    // Make max cache size HUGE, so that evictions don't happen below
+    cache->setMaximumCacheSize(qint64(HugeCacheLimit));
+    cache->clear();
+
+    //populate some fake data to simulate partially full cache
+    injectFakeData();
+
+    //Sanity-check that the URL is already in there somewhere
+    QVERIFY(isUrlCached(NumRemovals-1) == true);
+    //Entries in the cache should be > what we try to remove
+    QVERIFY(NumFakeCacheObjects > NumRemovals);
+
+
+    //Set cache limit lower, so this force 1 round of eviction
+    cache->setMaximumCacheSize(qint64(TinyCacheLimit));
+
+    //time insertions of additional content, which is likely to internally cause evictions
+    QBENCHMARK_ONCE {
+        for (quint32 i = NumFakeCacheObjects; i < (NumFakeCacheObjects + NumInsertions); i++) {
+            //prepare metata for url
+            QNetworkCacheMetaData meta;
+            QString fakeURL;
+            QTextStream stream(&fakeURL);
+            stream << fakeURLbase << i;//codescanner::leave
+            QUrl url(fakeURL);
+            meta.setUrl(url);
+            meta.setSaveToDisk(true);
+
+            //commit payload and metadata to disk
+            QIODevice *device = cache->prepare(meta);
+            device->write(payload);
+            cache->insert(device); // this should trigger evictions, if TinyCacheLimit is small enough
+        }
+    }
+
+    //Cleanup (slow)
+    cleanupCacheObject();
+    cleanRecursive(cacheDir);
+
+}
+// This function simulates a partially or fully occupied disk cache
+// like a normal user of a cache might encounter is real-life browsing.
+// The point of this is to trigger degradation in file-system and media performance
+// that occur due to the quantity and layout of data.
+void tst_qnetworkdiskcache::injectFakeData()
+{
+
+    QNetworkCacheMetaData::RawHeaderList headers;
+    headers.append(qMakePair(QByteArray("X-TestHeader"),QByteArray("HeaderValue")));
+
+
+    //Prep cache dir with fake data using QNetworkDiskCache APIs
+    for (quint32 i = 0; i < NumFakeCacheObjects; i++) {
+
+        //prepare metata for url
+        QNetworkCacheMetaData meta;
+        QString fakeURL;
+        QTextStream stream(&fakeURL);
+        stream << fakeURLbase << i;
+        QUrl url(fakeURL);
+        meta.setUrl(url);
+        meta.setRawHeaders(headers);
+        meta.setSaveToDisk(true);
+
+        //commit payload and metadata to disk
+        QIODevice *device = cache->prepare(meta);
+        device->write(payload);
+        cache->insert(device);
+    }
+
+}
+
+
+// Checks if the fake URL #id is already cached or not.
+bool tst_qnetworkdiskcache::isUrlCached(quint32 id)
+{
+    QString str;
+    QTextStream stream(&str);
+    stream << fakeURLbase << id;
+    QUrl url(str);
+    QIODevice *iod = cache->data(url);
+    return ((iod == 0) ? false : true) ;
+
+}
+
+
+// Utility function for recursive directory cleanup.
+void tst_qnetworkdiskcache::cleanRecursive(QString &path)
+{
+    QDirIterator it(path, QDir::Files | QDir::NoDotAndDotDot, QDirIterator::Subdirectories);
+    while (it.hasNext()) {
+        QFile f(it.next());
+        bool err = f.remove();
+        Q_UNUSED(err);
+    }
+
+    QDirIterator it2(path, QDir::AllDirs | QDir::NoDotAndDotDot, QDirIterator::Subdirectories);
+    while (it2.hasNext()) {
+        QString s(it2.next());
+        QDir dir(s);
+        dir.rmdir(s);
+    }
+}
+
+void tst_qnetworkdiskcache::cleanupCacheObject()
+{
+    delete cache;
+    cache = 0;
+}
+
+void tst_qnetworkdiskcache::initCacheObject()
+{
+
+   cache = new QNetworkDiskCache();
+
+}
+QTEST_MAIN(tst_qnetworkdiskcache)
+#include "tst_qnetworkdiskcache.moc"

tests/benchmarks/network/access/qnetworkreply/CMakeLists.txt

@@ -0,0 +1,16 @@
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+#####################################################################
+## tst_bench_qnetworkreply Binary:
+#####################################################################
+
+qt_internal_add_benchmark(tst_bench_qnetworkreply
+    SOURCES
+        tst_qnetworkreply.cpp
+    LIBRARIES
+        Qt::CorePrivate
+        Qt::Network
+        Qt::NetworkPrivate
+        Qt::Test
+)

tests/benchmarks/network/access/qnetworkreply/tst_qnetworkreply.cpp

@@ -0,0 +1,935 @@
+// Copyright (C) 2020 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+// This file contains benchmarks for QNetworkReply functions.
+
+#include <QDebug>
+#include <qtest.h>
+#include <QTest>
+#include <QTestEventLoop>
+#include <QSemaphore>
+#include <QTimer>
+#include <QtCore/qrandom.h>
+#include <QtCore/QElapsedTimer>
+#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"
+
+#ifdef QT_BUILD_INTERNAL
+#include <QtNetwork/private/qhostinfo_p.h>
+#endif
+
+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() override
+    {
+        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()));
+
+        QElapsedTimer 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();
+    }
+};
+
+
+typedef QSharedPointer<QNetworkReply> QNetworkReplyPtr;
+
+class DataReader: public QObject
+{
+    Q_OBJECT
+public:
+    qint64 totalBytes;
+    QByteArray data;
+    QIODevice *device;
+    bool accumulate;
+    DataReader(const QNetworkReplyPtr &dev, bool acc = true) : totalBytes(0), device(dev.data()), accumulate(acc)
+    {
+        connect(device, SIGNAL(readyRead()), SLOT(doRead()));
+    }
+    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 port;
+public:
+    qint64 transferRate;
+    ThreadedDataReader()
+        : port(-1), transferRate(-1)
+    {
+        start();
+        ready.acquire();
+    }
+
+    inline int serverPort() const { return port; }
+
+protected:
+    void run() override
+    {
+        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()));
+
+        QElapsedTimer 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); }
+
+    bool isSequential() const override { return true; }
+    qint64 bytesAvailable() const override { return state == Started ? 1024*1024 : 0; }
+
+public slots:
+    void start() { state = Started; emit readyRead(); }
+    void stop() { state = Stopped; emit readyRead(); }
+
+protected:
+    qint64 readData(char *data, qint64 maxlen) override
+    {
+        if (state == Stopped)
+            return -1;          // EOF
+
+        // return as many bytes as are wanted
+        memset(data, '@', maxlen);
+        return maxlen;
+    }
+    qint64 writeData(const char *, qint64) override { 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 port;
+public:
+    qint64 transferRate;
+    ThreadedDataReaderHttpServer()
+        : port(-1), transferRate(-1)
+    {
+        start();
+        ready.acquire();
+    }
+
+    inline int serverPort() const { return port; }
+
+protected:
+    void run() override
+    {
+        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()));
+
+        QElapsedTimer 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;
+    }
+
+    qint64 bytesAvailable() const override
+    {
+        return state == Started ? toBeGeneratedCount + QIODevice::bytesAvailable() : 0;
+    }
+
+    bool isSequential() const override { return false; }
+
+    bool reset() override { return false; }
+
+    qint64 size() const override { return toBeGeneratedTotalCount; }
+
+public slots:
+    void start() { state = Started; emit readyRead(); }
+
+protected:
+    qint64 readData(char *data, qint64 maxlen) override
+    {
+        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;
+    }
+    qint64 writeData(const char *, qint64) override { 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").toLatin1());
+        if (chunkedEncoding)
+            client->write(QString("Transfer-Encoding: chunked\n").toLatin1());
+        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").toLatin1());
+
+            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").toLatin1());
+                client->write(data.constData(), amount);
+                client->write(QString("\r\n").toLatin1());
+            } 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;
+
+public:
+    using QObject::connect;
+    bool connect(const QNetworkReplyPtr &sender, const char *signal, const QObject *receiver, const char *slot, Qt::ConnectionType ct = Qt::AutoConnection)
+    { return connect(sender.data(), signal, receiver, slot, ct); }
+private slots:
+    void initTestCase();
+    void httpLatency();
+
+#ifndef QT_NO_SSL
+    void echoPerformance_data();
+    void echoPerformance();
+    void preConnectEncrypted();
+#endif // !QT_NO_SSL
+    void preConnectEncrypted_data();
+
+    void downloadPerformance();
+    void uploadPerformance();
+    void performanceControlRate();
+    void httpUploadPerformance();
+    void httpDownloadPerformance_data();
+    void httpDownloadPerformance();
+    void httpDownloadPerformanceDownloadBuffer_data();
+    void httpDownloadPerformanceDownloadBuffer();
+    void httpsRequestChain();
+    void httpsUpload();
+    void preConnect_data();
+    void preConnect();
+
+private:
+    void runHttpsUploadRequest(const QByteArray &data, const QNetworkRequest &request);
+    QPair<QNetworkReply *, qint64> runGetRequest(QNetworkAccessManager *manager,
+                                                 const QNetworkRequest &request);
+};
+
+void tst_qnetworkreply::initTestCase()
+{
+    if (!QtNetworkSettings::verifyTestNetworkSettings())
+        QSKIP("No network test server available");
+}
+
+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;
+    }
+}
+
+QPair<QNetworkReply *, qint64> tst_qnetworkreply::runGetRequest(
+        QNetworkAccessManager *manager, const QNetworkRequest &request)
+{
+    QElapsedTimer timer;
+    timer.start();
+    QNetworkReply *reply = manager->get(request);
+    connect(reply, SIGNAL(sslErrors(QList<QSslError>)), reply, SLOT(ignoreSslErrors()));
+    connect(reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()), Qt::QueuedConnection);
+    QTestEventLoop::instance().enterLoop(20);
+    qint64 elapsed = timer.elapsed();
+    return qMakePair(reply, elapsed);
+}
+
+#ifndef QT_NO_SSL
+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 (size_t i = 0; i < data.size() / sizeof(int); i++) {
+        char r = char(QRandomGenerator::global()->generate());
+        data.data()[i*sizeof(int)] = r;
+    }
+
+    QBENCHMARK{
+        QNetworkReply* reply = manager.post(request, data);
+        connect(reply, SIGNAL(sslErrors(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;
+    }
+}
+
+void tst_qnetworkreply::preConnectEncrypted()
+{
+    QFETCH(int, sleepTime);
+    QString hostName = QLatin1String("www.google.com");
+
+    QNetworkAccessManager manager;
+    QNetworkRequest request(QUrl("https://" + hostName));
+
+    // make sure we have a full request including
+    // DNS lookup, TCP and SSL handshakes
+#ifdef QT_BUILD_INTERNAL
+    qt_qhostinfo_clear_cache();
+#else
+    qWarning("no internal build, could not clear DNS cache. Results may not be representative.");
+#endif
+
+    // first, benchmark a normal request
+    QPair<QNetworkReply *, qint64> normalResult = runGetRequest(&manager, request);
+    QNetworkReply *normalReply = normalResult.first;
+    QVERIFY(!QTestEventLoop::instance().timeout());
+    QVERIFY(normalReply->error() == QNetworkReply::NoError);
+    qint64 normalElapsed = normalResult.second;
+
+    // clear all caches again
+#ifdef QT_BUILD_INTERNAL
+    qt_qhostinfo_clear_cache();
+#else
+    qWarning("no internal build, could not clear DNS cache. Results may not be representative.");
+#endif
+    manager.clearAccessCache();
+
+    // now try to make the connection beforehand
+    manager.connectToHostEncrypted(hostName);
+    QTestEventLoop::instance().enterLoopMSecs(sleepTime);
+
+    // now make another request and hopefully use the existing connection
+    QPair<QNetworkReply *, qint64> preConnectResult = runGetRequest(&manager, request);
+    QNetworkReply *preConnectReply = normalResult.first;
+    QVERIFY(!QTestEventLoop::instance().timeout());
+    QVERIFY(preConnectReply->error() == QNetworkReply::NoError);
+    qint64 preConnectElapsed = preConnectResult.second;
+    qDebug() << request.url().toString() << "full request:" << normalElapsed
+             << "ms, pre-connect request:" << preConnectElapsed << "ms, difference:"
+             << (normalElapsed - preConnectElapsed) << "ms";
+}
+
+#endif // !QT_NO_SSL
+
+void tst_qnetworkreply::preConnectEncrypted_data()
+{
+#ifndef QT_NO_OPENSSL
+    QTest::addColumn<int>("sleepTime");
+    // start a new normal request after preconnecting is done
+    QTest::newRow("HTTPS-2secs") << 2000;
+
+    // start a new normal request while preconnecting is in-flight
+    QTest::newRow("HTTPS-100ms") << 100;
+#endif // QT_NO_OPENSSL
+}
+
+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(QUrl(QStringLiteral("debugpipe://127.0.0.1:") + QString::number(sender.serverPort()) + QStringLiteral("/?bare=1")));
+    QNetworkReplyPtr reply(manager.get(request));
+    DataReader reader(reply, false);
+
+    QElapsedTimer 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(QUrl(QStringLiteral("debugpipe://127.0.0.1:") + QString::number(reader.serverPort()) + QStringLiteral("/?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());
+}
+
+constexpr qint64 MiB = 1024 * 1024;
+
+void tst_qnetworkreply::httpUploadPerformance()
+{
+      constexpr qint64 UploadSize = 128 * MiB;
+
+      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()));
+
+      QElapsedTimer 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);
+
+    QElapsedTimer 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);
+
+    constexpr qint64 UploadSize = 128 * MiB;
+
+    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.data());
+
+    QElapsedTimer 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*) malloc(uploadSize);
+            QVERIFY(reply->read(replyData, uploadSize) == uploadSize);
+            free(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*) malloc(uploadSize);
+            QVERIFY(reply->read(replyData, uploadSize) == uploadSize);
+            free(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.
+    enum {UploadSize = 32*1024*1024}; // 32 MB
+
+    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.data(), testType, UploadSize);
+
+    QBENCHMARK_ONCE {
+        QTestEventLoop::instance().enterLoop(40);
+        QCOMPARE(reply->error(), QNetworkReply::NoError);
+        QVERIFY(reply->isFinished());
+        QVERIFY(!QTestEventLoop::instance().timeout());
+    }
+}
+
+
+class HttpsRequestChainHelper : public QObject {
+    Q_OBJECT
+public:
+    QList<QNetworkRequest> requestList;
+
+    QElapsedTimer timeOneRequest;
+    QList<qint64> timeList;
+
+    QElapsedTimer globalTime;
+
+    QNetworkAccessManager manager;
+
+    HttpsRequestChainHelper() {
+    }
+public slots:
+    void doNextRequest() {
+        // all requests done
+        if (requestList.isEmpty()) {
+            QTestEventLoop::instance().exitLoop();
+            return;
+        }
+
+        if (qobject_cast<QNetworkReply*>(sender()) == 0) {
+            // first start after DNS lookup, start timer
+            globalTime.start();
+        }
+        QNetworkReply *reply = qobject_cast<QNetworkReply*>(sender());
+        if (reply) {
+            QVERIFY(reply->error() == QNetworkReply::NoError);
+            qDebug() << "time =" << timeOneRequest.elapsed() << "ms";
+            timeList.append(timeOneRequest.elapsed());
+        }
+
+        QNetworkRequest request = requestList.takeFirst();
+        timeOneRequest.restart();
+        reply = manager.get(request);
+        QObject::connect(reply, SIGNAL(sslErrors(QList<QSslError>)), reply, SLOT(ignoreSslErrors()));
+        QObject::connect(reply, SIGNAL(finished()), this, SLOT(doNextRequest()));
+    }
+
+};
+
+void tst_qnetworkreply::httpsRequestChain()
+{
+    int count = 10;
+
+    QNetworkRequest request(QUrl("https://" + QtNetworkSettings::serverName() + "/fluke.gif"));
+    // Disable keep-alive so we have the full re-connecting of TCP.
+    request.setRawHeader("Connection", "close");
+
+    HttpsRequestChainHelper helper;
+    for (int i = 0; i < count; i++)
+        helper.requestList.append(request);
+
+    // Warm up DNS cache and then immediately start HTTP
+    QHostInfo::lookupHost(QtNetworkSettings::serverName(), &helper, SLOT(doNextRequest()));
+
+    // we can use QBENCHMARK_ONCE when we find out how to make it really run once.
+    // there is still a warmup-run :(
+
+    //QBENCHMARK_ONCE {
+        QTestEventLoop::instance().enterLoop(40);
+        QVERIFY(!QTestEventLoop::instance().timeout());
+    //}
+
+    qint64 elapsed = helper.globalTime.elapsed();
+
+    qint64 average = (elapsed / count);
+
+    std::sort(helper.timeList.begin(), helper.timeList.end());
+    qint64 median = helper.timeList.at(5);
+
+    qDebug() << "Total:" << elapsed << "   Average:" << average << "   Median:" << median;
+
+}
+
+void tst_qnetworkreply::runHttpsUploadRequest(const QByteArray &data, const QNetworkRequest &request)
+{
+    QNetworkReply* reply = manager.post(request, data);
+    reply->ignoreSslErrors();
+    connect(reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()));
+    QTestEventLoop::instance().enterLoop(15);
+    QVERIFY(!QTestEventLoop::instance().timeout());
+    QCOMPARE(reply->error(), QNetworkReply::NoError);
+    reply->deleteLater();
+}
+
+void tst_qnetworkreply::httpsUpload()
+{
+    QByteArray data = QByteArray(2*1024*1024+1, '\177');
+    QNetworkRequest request(QUrl("https://" + QtNetworkSettings::serverName() + "/qtest/cgi-bin/md5sum.cgi"));
+    request.setHeader(QNetworkRequest::ContentTypeHeader, "application/octet-stream");
+//    for (int a = 0; a < 10; ++a)
+//        runHttpsUploadRequest(data, request); // to warmup all TCP connections
+    QBENCHMARK {
+        runHttpsUploadRequest(data, request);
+    }
+}
+
+void tst_qnetworkreply::preConnect_data()
+{
+    preConnectEncrypted_data();
+}
+
+void tst_qnetworkreply::preConnect()
+{
+    QString hostName = QLatin1String("www.google.com");
+
+    QNetworkAccessManager manager;
+    QNetworkRequest request(QUrl("http://" + hostName));
+
+    // make sure we have a full request including
+    // DNS lookup and TCP handshake
+#ifdef QT_BUILD_INTERNAL
+    qt_qhostinfo_clear_cache();
+#else
+    qWarning("no internal build, could not clear DNS cache. Results may not be representative.");
+#endif
+
+    // first, benchmark a normal request
+    QPair<QNetworkReply *, qint64> normalResult = runGetRequest(&manager, request);
+    QNetworkReply *normalReply = normalResult.first;
+    QVERIFY(!QTestEventLoop::instance().timeout());
+    QVERIFY(normalReply->error() == QNetworkReply::NoError);
+    qint64 normalElapsed = normalResult.second;
+
+    // clear all caches again
+#ifdef QT_BUILD_INTERNAL
+    qt_qhostinfo_clear_cache();
+#else
+    qWarning("no internal build, could not clear DNS cache. Results may not be representative.");
+#endif
+    manager.clearAccessCache();
+
+    // now try to make the connection beforehand
+    QFETCH(int, sleepTime);
+    manager.connectToHost(hostName);
+    QTestEventLoop::instance().enterLoopMSecs(sleepTime);
+
+    // now make another request and hopefully use the existing connection
+    QPair<QNetworkReply *, qint64> preConnectResult = runGetRequest(&manager, request);
+    QNetworkReply *preConnectReply = normalResult.first;
+    QVERIFY(!QTestEventLoop::instance().timeout());
+    QVERIFY(preConnectReply->error() == QNetworkReply::NoError);
+    qint64 preConnectElapsed = preConnectResult.second;
+    qDebug() << request.url().toString() << "full request:" << normalElapsed
+             << "ms, pre-connect request:" << preConnectElapsed << "ms, difference:"
+             << (normalElapsed - preConnectElapsed) << "ms";
+}
+
+QTEST_MAIN(tst_qnetworkreply)
+
+#include "tst_qnetworkreply.moc"

tests/benchmarks/network/access/qnetworkreply_from_cache/CMakeLists.txt

@@ -0,0 +1,14 @@
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+#####################################################################
+## tst_bench_qnetworkreply_from_cache Binary:
+#####################################################################
+
+qt_internal_add_benchmark(tst_bench_qnetworkreply_from_cache
+    SOURCES
+        tst_qnetworkreply_from_cache.cpp
+    LIBRARIES
+        Qt::Network
+        Qt::Test
+)

tests/benchmarks/network/access/qnetworkreply_from_cache/tst_qnetworkreply_from_cache.cpp

@@ -0,0 +1,194 @@
+// Copyright (C) 2012 Hewlett-Packard Development Company, L.P.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#include <QTest>
+#include <QBuffer>
+#include <QTestEventLoop>
+#include <QtNetwork/QNetworkAccessManager>
+#include <QtNetwork/QNetworkDiskCache>
+#include <QtNetwork/QNetworkReply>
+#include <QtNetwork/QTcpServer>
+#include <QtNetwork/QTcpSocket>
+
+#define TEST_CASE_TIMEOUT 30
+
+class NetworkDiskCache : public QNetworkDiskCache
+{
+public:
+    NetworkDiskCache(QObject *parent = nullptr)
+        : QNetworkDiskCache(parent)
+    {
+    }
+
+    QByteArray cachedData;
+
+    QNetworkCacheMetaData metaData(const QUrl &url) override
+    {
+        QNetworkCacheMetaData metaData;
+        if (!cachedData.isEmpty()) {
+            metaData.setUrl(url);
+            QDateTime now = QDateTime::currentDateTime();
+            metaData.setLastModified(now.addDays(-1));
+            metaData.setExpirationDate(now.addDays(1));
+            metaData.setSaveToDisk(true);
+        }
+        return metaData;
+    }
+
+    QIODevice *data(const QUrl &/*url*/) override
+    {
+        if (cachedData.isEmpty())
+            return 0;
+
+        QBuffer *buffer = new QBuffer;
+        buffer->setData(cachedData);
+        buffer->open(QIODevice::ReadOnly);
+        return buffer;
+    }
+};
+
+class HttpServer : public QTcpServer
+{
+    Q_OBJECT
+public:
+    HttpServer(const QByteArray &reply)
+        : m_reply(reply), m_writePos(), m_client()
+    {
+        listen(QHostAddress::AnyIPv4);
+        connect(this, SIGNAL(newConnection()), this, SLOT(accept()));
+    }
+
+private Q_SLOTS:
+    void accept()
+    {
+        m_client = nextPendingConnection();
+        m_client->setParent(this);
+        connect(m_client, SIGNAL(readyRead()), this, SLOT(reply()));
+    }
+
+    void reply()
+    {
+        disconnect(m_client, SIGNAL(readyRead()));
+        m_client->readAll();
+        connect(m_client, SIGNAL(bytesWritten(qint64)), this, SLOT(write()));
+        write();
+    }
+
+    void write()
+    {
+        qint64 pos = m_client->write(m_reply.mid(m_writePos));
+        if (pos > 0)
+            m_writePos += pos;
+        if (m_writePos >= m_reply.size())
+            m_client->disconnect();
+    }
+
+private:
+    QByteArray m_reply;
+    qint64 m_writePos;
+    QTcpSocket *m_client;
+};
+
+class tst_qnetworkreply_from_cache : public QObject
+{
+    Q_OBJECT
+public:
+    tst_qnetworkreply_from_cache();
+
+    void timeReadAll(const QString &headers, const QByteArray &data = QByteArray());
+
+private Q_SLOTS:
+    void initTestCase();
+    void cleanup();
+
+    void readAll_data();
+    void readAll();
+    void readAllFromCache_data();
+    void readAllFromCache();
+
+protected Q_SLOTS:
+    void replyReadAll() { m_replyData += m_reply->readAll(); }
+
+private:
+    QTemporaryDir m_tempDir;
+    QNetworkAccessManager *m_networkAccessManager;
+    NetworkDiskCache *m_networkDiskCache;
+    QNetworkReply *m_reply;
+    QByteArray m_replyData;
+};
+
+tst_qnetworkreply_from_cache::tst_qnetworkreply_from_cache()
+    : m_tempDir(QDir::tempPath() + "/tst_qnetworkreply_from_cache.XXXXXX")
+{
+}
+
+void tst_qnetworkreply_from_cache::timeReadAll(const QString &headers, const QByteArray &data)
+{
+    QByteArray reply;
+    reply.append(headers.toUtf8());
+    reply.append(data);
+
+    m_replyData.reserve(data.size());
+
+    HttpServer server(reply);
+
+    QBENCHMARK_ONCE {
+        QNetworkRequest request(QUrl(QString("http://127.0.0.1:%1").arg(server.serverPort())));
+        m_reply = m_networkAccessManager->get(request);
+        connect(m_reply, SIGNAL(readyRead()), this, SLOT(replyReadAll()), Qt::QueuedConnection);
+        connect(m_reply, SIGNAL(finished()), &QTestEventLoop::instance(), SLOT(exitLoop()), Qt::QueuedConnection);
+        QTestEventLoop::instance().enterLoop(TEST_CASE_TIMEOUT);
+        QVERIFY(!QTestEventLoop::instance().timeout());
+        delete m_reply;
+    }
+
+    QCOMPARE(data.size(), m_replyData.size());
+    QCOMPARE(data, m_replyData);
+}
+
+void tst_qnetworkreply_from_cache::initTestCase()
+{
+    m_networkAccessManager = new QNetworkAccessManager(this);
+    m_networkDiskCache = new NetworkDiskCache(m_networkAccessManager);
+    m_networkDiskCache->setCacheDirectory(m_tempDir.path());
+    m_networkAccessManager->setCache(m_networkDiskCache);
+}
+
+void tst_qnetworkreply_from_cache::cleanup()
+{
+    m_replyData.clear();
+}
+
+void tst_qnetworkreply_from_cache::readAll_data()
+{
+    QTest::addColumn<int>("dataSize");
+    QTest::newRow("1MB") << (int)1e6;
+    QTest::newRow("5MB") << (int)5e6;
+    QTest::newRow("10MB") << (int)10e6;
+}
+
+void tst_qnetworkreply_from_cache::readAll()
+{
+    QFETCH(int, dataSize);
+    QString headers = QString("HTTP/1.0 200 OK\r\nContent-Length: %1\r\n\r\n").arg(dataSize);
+    QByteArray data(QByteArray(dataSize, (char)42));
+    m_networkDiskCache->cachedData.clear();
+    timeReadAll(headers, data);
+}
+
+void tst_qnetworkreply_from_cache::readAllFromCache_data()
+{
+    readAll_data();
+}
+
+void tst_qnetworkreply_from_cache::readAllFromCache()
+{
+    QFETCH(int, dataSize);
+    QByteArray headers("HTTP/1.0 304 Use Cache\r\n\r\n");
+    QByteArray data(QByteArray(dataSize, (char)42));
+    m_networkDiskCache->cachedData = data;
+    timeReadAll(headers, data);
+}
+
+QTEST_MAIN(tst_qnetworkreply_from_cache)
+#include "tst_qnetworkreply_from_cache.moc"