LibArchiveWrapper: use local zero-timer for processing server signals

Now that the server process may request file seeks in addition to reads
for archive formats supporting them, the interval which we process the
requests will have a big impact on the extracting speed.

Also shrink the read buffer as its size isn't as significant for the
performance after this change.

Task-number: QTIFW-2384
Change-Id: Iaf296833c6ff1acfc666a6e82f661e1a40c77b61
Reviewed-by: Katja Marttila <katja.marttila@qt.io>

2 files changed, 7 insertions, 9 deletions

diff --git a/src/libs/installer/libarchivewrapper_p.cpp b/src/libs/installer/libarchivewrapper_p.cpp
index 75bbddbe8..30f81554a 100644
--- a/src/libs/installer/libarchivewrapper_p.cpp
+++ b/src/libs/installer/libarchivewrapper_p.cpp
@@ -77,7 +77,6 @@ LibArchiveWrapperPrivate::LibArchiveWrapperPrivate()
 */
 LibArchiveWrapperPrivate::~LibArchiveWrapperPrivate()
 {
-    m_timer.stop();
 }
 
 /*!
@@ -140,6 +139,10 @@ QString LibArchiveWrapperPrivate::errorString() const
 bool LibArchiveWrapperPrivate::extract(const QString &dirPath, const quint64 totalFiles)
 {
     if (connectToServer()) {
+        QTimer timer;
+        connect(&timer, &QTimer::timeout, this, &LibArchiveWrapperPrivate::processSignals);
+        timer.start();
+
         m_lock.lockForWrite();
         callRemoteMethod(QLatin1String(Protocol::AbstractArchiveExtract), dirPath, totalFiles);
         m_lock.unlock();
@@ -148,6 +151,7 @@ bool LibArchiveWrapperPrivate::extract(const QString &dirPath, const quint64 tot
             connect(this, &LibArchiveWrapperPrivate::remoteWorkerFinished, &loop, &QEventLoop::quit);
             loop.exec();
         }
+        timer.stop();
         return (workerStatus() == ExtractWorker::Success);
     }
     return m_archive.extract(dirPath, totalFiles);
@@ -262,7 +266,7 @@ void LibArchiveWrapperPrivate::processSignals()
 */
 void LibArchiveWrapperPrivate::onDataBlockRequested()
 {
-    constexpr quint64 blockSize = 10 * 1024 * 1024; // 10MB
+    constexpr quint64 blockSize = 1024 * 1024; // 1MB
 
     QFile *const file = &m_archive.m_data->file;
     if (!file->isOpen() || file->isSequential()) {
@@ -327,15 +331,10 @@ void LibArchiveWrapperPrivate::onSeekRequested(qint64 offset, int whence)
 }
 
 /*!
-    Starts the timer to process server-side signals and connects handler
-    signals for the matching signals of the wrapper object.
+    Connects handler signals for the matching signals of the wrapper object.
 */
 void LibArchiveWrapperPrivate::init()
 {
-    m_timer.start(250);
-    QObject::connect(&m_timer, &QTimer::timeout,
-                     this, &LibArchiveWrapperPrivate::processSignals);
-
     QObject::connect(&m_archive, &LibArchiveArchive::currentEntryChanged,
                      this, &LibArchiveWrapperPrivate::currentEntryChanged);
     QObject::connect(&m_archive, &LibArchiveArchive::completedChanged,
diff --git a/src/libs/installer/libarchivewrapper_p.h b/src/libs/installer/libarchivewrapper_p.h
index 722c91f17..4277cd4f9 100644
--- a/src/libs/installer/libarchivewrapper_p.h
+++ b/src/libs/installer/libarchivewrapper_p.h
@@ -86,7 +86,6 @@ private:
     ExtractWorker::Status workerStatus() const;
 
 private:
-    QTimer m_timer;
     mutable QReadWriteLock m_lock;
 
     LibArchiveArchive m_archive;