From 10:00 CET Friday 22nd November we will adjust how the server works to deal with some recently reported problems. Therefore there may be a load problem, if you experience more problems than usual trying to access the forum then please PM AndyS or any of the moderators so they can inform me.

The speed of applications

  • Hi,

    I have been using mini2440 and micro2440 too and I am absolutely satisfied with them. I use Qt too. I have got only one problem. But this makes me crazy. :-) My applications are slow. I absolutely cannot figure out what the problem is.

    When I wrote “slow” I meant it is 2-4 seconds between any two GUI operations. So it is a really big problem to me. I haven’t found anybody with the same problem even though I had visited many forums. I tried with compiled Qt as well to avoid my errors but the result was the same. I also was thinking of switching optimization but it was said that it wouldn’t work.
    Any help or advice would be great. :-)

    I made a video to illustrate my problem. You can reach it on the following link:

    The languages is not important. But you can see the long delay.

    Best luck for us, :-)

  • if you have a profiler for your setup, and see which parts of the application take most time. You can try valgrid/calgrind. Mostly its a matter of compiling and running those application.

  • Thanks, I will check it. D.

  • There is one more thing. I compiled it for host too. It worked perfectly. My host is a ubuntu under VMplayer. So the host is not fast.

  • Not sure if this will help, but when we were developing on a system with similar specs we found that style sheets and complex layouts were the slowest points in our application.

  • Hi,
    I am again. I have checked what you had recommended.
    As I mentioned there is no problem in the environment of my host.
    Is it true, that I cannot use this on my mini2440? (I am not sure, because this is the first time I try to use valgrind).

    I have just seen your answer. I agree with you, that there are some widgets which are a bit slower than others. But I suppose some should work better. I would improve them. Thank you really. :-)


  • I have read that different Qt has different speed. Therefore I would like to compile the newest, maybe It is enough fast.
    I downloaded it. I started to compile it, but I found some differences.

    1. The g++.conf file has been devide into two different file. Both of two files contain flags for optimization. Where I can switch of the optimization?
    2. I cannot configure. The old one that I used until yet is the next:
    3. /configure -embedded arm -xplatform qws/linux-arm-g++ -prefix /usr/local/Qt -qt-mouse-tslib -little-endian -no-webkit -no-qt3support -no-cups -no-largefile -optimized-qmake -no-openssl -nomake tools -qt-sql-sqlite -no-3dnow -system-zlib -qt-gif -qt-libtiff -qt-libpng -qt-libmng -qt-libjpeg -no-opengl -gtkstyle -no-openvg -no-xshape -no-xsync -no-xrandr -qt-freetype -qt-gfx-linuxfb -qt-kbd-tty -qt-kbd-linuxinput -qt-mouse-tslib -qt-mouse-linuxinput

    But it doesn’t work. I got the next message:
    qt-gif: invalid command-line switch
    -qt-gfx-linuxfb: unknown argument
    -qt-kbd-tty: unknown argument
    -qt-kbd-linuxinput: unknown argument
    -qt-mouse-tslib: unknown argument
    -qt-mouse-linuxinput: unknown argument
    You have not explicitly asked to use pkg-config and are cross-compiling.
    pkg-config will not be used to automatically query cflag/lib parameters for

    If it is possible I would like to compile with static flag to reach better speed. How can I do it?
    Thank you, D.

  • Hi,

    i know its a long time since your post but I bought a mini2440 a few weeks ago and now have the same problems...
    Did you (successfully) solved your problem?

    Thanks and best regards

  • I don't know if it is the same problem... but I found on the Qt 5.1 and Qt 5.2 beta1 on Android and iOS that the QML Text item make a very long time to load. But after that, it's very fast.
    So, I had the same problem of switching from a screen to another (I'm talking about QML), and to solve it, I loaded all the QML Text items at the startup and then all switching between screens are now very fast.
    But, now the startup of the application takes almost 10 seconds :-(

  • Hi,

    thanks for your reply, but this problem occurs with qt4.6.2; so no qml...

    Best regards

Log in to reply