https://bugs.kde.org/show_bug.cgi?id=527144
Robin <[email protected]> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |[email protected] --- Comment #4 from Robin <[email protected]> --- (In reply to Zamundaaa from comment #1) > This is likely a regression caused by commit timing. It makes everything a > lot more complicated since we get more commits from apps than they actually > render frames. > > I tested VRR + commit timing with > MANGOHUD_CONFIG=fps_limit=60 mangohud vkcube > before, and that still looks smooth to me. Does it also hit the issue for > you? Same issue here on KWin 6.8.0 (CachyOS, RX 6700M, 2560x1440@180Hz, VRR auto, fullscreen with direct scanout). Game: Stellar Blade via Proton/vkd3d-proton with FSR3 frame generation. I traced it (ftrace + kprobes on the syncobj eventfd + Mesa WSI markers): - The game presents every 7-9 ms (~122 fps) and KWin receives each buffer within 0.5 ms, already signaled. - Still, KWin only shows ~75% of the frames (931 of 1228 in 10 s) and delays others by up to 16 ms, with ~26 ms gaps. - Stock Mesa/kernel (~94 fps): ~17% of frames dropped. - With a 90 fps cap (VKD3D_FRAME_RATE=90) it is perfectly smooth: no drops, flips steady at 11.1 ms. - Nested in gamescope it is also smooth. So frames arrive on time and ready, but KWin's commit scheduling with direct scanout + VRR drops or delays them. (Most traces used a patched RADV/amdgpu with a second GFX queue, but stock shows the same problem.) Raw traces available if needed. -- You are receiving this mail because: You are watching all bug changes.
