Vsync rate is halved in in RetroArch using RetroArch's Vulkan backend with a 2 buffers swapchain and Direct Scanout
Good morning,
Using:
-RetroArch's Vulkan backend (not to be confused with WLRoots Vulkan backend, which is totally unrelated to this issue).
-With a 2 buffers swapchain (by setting Settings->Video->Synchronization->Max Swapchain Images
to 2
).
-In fullscreen mode.
-On any WlRoots-based compositor with Direct Scanout enabled.
...Results on halved vsync rate.
This means that, for example, 60Hz video modes result in a 30Hz vsync rate (can be observed empirically, but also on Settings->Video->Output->Estimated Screen Refresh Rate
).
This is using latest GIT master branch WLRoots, also with latest stable WLRoots (0.17.3), and latest stable MESA (24.1.1) with Intel N100 GPU and I5-1235U with XE graphics.
As per issue report guidelines, I have reported this issue to some individual WLRoots-based compositors, like for example: https://github.com/WayfireWM/wayfire/issues/2377
Also per issue report guidelines, I'm attaching the Sway log (if any other WLRoots-based compositor log is preferred, just tell me). swaylog.log