Qt Quick Framerate Qt5 vs Qt6

Hello, I'm starting to evaluate Qt6 for my projects. I ran a couple of tests to compare Qt5 to Qt6 and noticed something weird in my first test.

My benchmark is a simple Qt Quick application with a few animations and a framerate value shown in the interface.

What I see is that my calculation of the framerate reports a higher value of Qt5 vs Qt6 for the two platforms I tested: x64 Intel HD Linux on X11 and armv8-a Raspberry Pi 3B Linux on eglfs KMS.

Intel HD: ~40 vs ~31

VC4 Raspberry Pi: ~60 vs ~41

Are these values to be trusted? What do you consider to be the cause?

• The benchmark app can be found here: https://github.com/carlonluca/Fall
• This is how framerate is computed: https://github.com/carlonluca/lqtutils/blob/master/lqtutils_ui.cpp
• This is a video showing what I see: https://youtu.be/5fPRT4j_VJE