[Xcb] Question about xcb performance and threading support

[Clemens Eisserer]

HI Benoît,

> I have currently using valgrind / callgrind & kcachegrind with the Gambas IDE
> to try to understand why QT4.4 is slower than QT3.

QT4 is now double-buffered, furthermore it uses antialiasing for a lot
of its widgets and has a new painting engine which uses XRender
trapezoids. Unfourtunatly the trapezoids are not hw accalerated, so
they are slow compared to what QT3 did.

I am not 100% sure, but when running your benchmarks pay attention to
the time spent in Xorg in relation to the QT client.

- Clemens