Hi, Lucas! Thanks for the explanation. That fits the mental model I've built up.
As it turned out it was the Wayland client computing and displaying the FPS counter which reduced the FPS in the first place. Contrary to what I initially said the FPS reduction was also present using wl_drm (I got some numbers confused). With the compositor itself doing the FPS computation both protocols (wl_drm and dmabuf) show similar FPS numbers and low CPU usage. Christian
