How can we benchmark performance of Qt Wayland on a hardware platform? Do we have any benchmarking tools like "glmark2-es2" which is used for standard OpenGL benchmarking. This is required to see if we can use Qt Wayland compositor or have to use Wayland.
glmark2 works on Wayland as well, however it is not in it's current condition a good measure of actual performance. It tries to render frames as fast as possible, regardless of how fast the compositor is actually able to show them. This means most of the frames are wasted, and never shown on the screen. So what it usually measures is how good the compositor is at ignoring superfluous frames from a misbehaving client (most clients wait for the compositor to tell them to draw a new frame so it can be close to vsync). Actually, a compositor locked at a ridiculously low frame rate can more easily achieve a high glmark2 score than one running at a steady 60fps.
Instead, it's better to use a tool that tries to increase the workload per frame while keeping the frame-rate constant at 60fps.
If you're using Qt anyway, then one such tool is https://github.com/CrimsonAS/qmlbench. You'll probably be able to find others if you want something toolkit independent.
EDIT: If you want more of my rants about why glmark2-es is a horrible tool to benchmark compositors, see http://blog.qt.io/blog/2017/05/31/qt-wayland-summary/#comment-1200024