QtWebEngine is extremely slow

[GimpMaster]

I've just recently started playing around with the QtWebEngine that runs on Chromium. I created a very simple QML project to just load a webpage. What I'm noticing is that the QtWebEngine (using WebEngineView) is extremely slow at loading sites. A coule google searches shows I'm not alone.

I'm using Window 7 with VS 2013, Qt 5.4.0 and also tried Qt 5.5.0 beta with the same results. For those interested here is my source code.


main.qml

import QtQuick 2.1
import QtQuick.Controls 1.1
import QtQuick.Layouts 1.1
import QtWebEngine 1.0
 
ApplicationWindow {
    width: 1280
    height: 720
    visible: true
	ColumnLayout {
		anchors.fill: parent
		TextField {
			id: addressBar
			focus: true
			Layout.fillWidth: true
			text: webView.url
			onAccepted: webView.url = text
		}
 
		WebEngineView {
			id: webview
			url: "www.google.com"
			Layout.fillWidth: true
			Layout.fillHeight: true
		}
	}
}

import QtQuick 2.1
import QtQuick.Controls 1.1
import QtQuick.Layouts 1.1
import QtWebEngine 1.0

ApplicationWindow {
    width: 1280
    height: 720
    visible: true
	ColumnLayout {
		anchors.fill: parent
		TextField {
			id: addressBar
			focus: true
			Layout.fillWidth: true
			text: webView.url
			onAccepted: webView.url = text
		}
		
		WebEngineView {
			id: webview
			url: "www.google.com"
			Layout.fillWidth: true
			Layout.fillHeight: true
		}
	}
}

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main.cpp

#include <QtGui/QGuiApplication>
#include <QtQml/QQmlApplicationEngine>
#include <QtWebEngine/qtwebengineglobal.h>
 
int main(int argc, char *argv[])
{
  QGuiApplication app(argc, argv);
  QtWebEngine::initialize();
  QQmlApplicationEngine appEngine;
  appEngine.load(QUrl("main.qml"));
 
  return app.exec();
}

#include <QtGui/QGuiApplication>
#include <QtQml/QQmlApplicationEngine>
#include <QtWebEngine/qtwebengineglobal.h>
 
int main(int argc, char *argv[])
{
  QGuiApplication app(argc, argv);
  QtWebEngine::initialize();
  QQmlApplicationEngine appEngine;
  appEngine.load(QUrl("main.qml"));
 
  return app.exec();
}

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Does anybody else use this QML item. Do you see this same issue?

[GimpMaster]

Hmm, no responses. Am I the only one having this problem? Are other people using the QWebEngine. The sample projects are just as slow.

[jefftee]

I have not used QWebEngine personally, but I just compiled/ran the quicknanobrowser example from Qt 5.4.1 and it doesn't seem slow to me. Can you define "extremely slow"?

[GimpMaster]

Thank you for responding. If for example I use Chrome or Firefox and load google.com it loads in probably 1-2 seconds. With the Nanobrowser example Google.com MIGHT load in 10-15 seconds. You can actually watch the jpeg images get downloaded scanline by scanline.

[jefftee]

Sorry, I see subsecond to 1 second response times loading google.com. Any DNS issues on your end perhaps? I don't know why else your load times would be so much worse.

[GimpMaster]

Interesting. I sent the application to a friend to try (after determining the massive number of files for deployment, manually) and he didn't see the same issues. Perhaps its something odd with my PC. Thanks for the help.

[alketi]

This bug may be of some help: https://bugreports.qt.io/browse/QTBUG-44763

It points to a problem with LAN adapters.

[GimpMaster]

Thank you so much! That was exactly the problem. I had a VPN adapter enabled and a Virtbox. Both not connected. When I disabled both adapters and kept my primary enabled it worked just great.