https://bugs.kde.org/show_bug.cgi?id=406180
--- Comment #54 from John A <drjohnny...@gmail.com> --- (In reply to Jeffery Patton from comment #51) > (In reply to John A from comment #50) > > I can confirm that the regression appears in Kubuntu 19.04 with kwin > > 5.15.90, an NVIDIA Optimus setup (NVIDIA is selected as the primary GPU), > > OpenGL 3.1 used as the rendering backend and options nvidia_drm modeset=1 > > set(to enable PRIME Synchronization and eliminate horizontal screen > > tearing). > > > > KWin hangs when using active screen edges (Present Windows), Alt-tabbing and > > sometimes when maximizing or moving a window. > > > > Switching the rendering backend to XRender resolves the issue. > > XRender doesn't resolve the issue, it's an ugly workaround that forces > software rendering. It's just about as bad as disabling Prime Sync. > > Thanks for confirming this affects the upcoming 5.16 as well though. Oh I agree that XRender is an ugly workaround. I was just pointing out that KWin does not hang when XRender is used as the rendering backend. In addition, the aforementioned fork (kwin-lowlatency) exhibits the same behaviour. I will apply the patches mentioned in this thread and report back. -- You are receiving this mail because: You are watching all bug changes.
