00:01 <mntirc> anarsoul: as far as i can see it's gnome-shell's built in compositor.

00:03 <mntirc> but i noticed now that the issue is most pronounced here because one of my displays is rotated and at scale 2, and when a window at the border between the two displays is repainted, it slows down everything. (not yet overlapping, but there is probably some invisible overlapping area)

00:19 <mntirc> ok, the problem is gtk3. it's reproducible with the gtk3-demo's "fishbowl" demo. resizing that demo to a big size will drag down the whole desktop's performance to <10fps. but the same demo in gtk4-demo stays at 120 fps (it's a 120hz screen)

10:45 <mntirc> after some discussion with rmader he pointed out that mutter somehow picks desktop GL on panfrost when it should use GLES. using COGL_DRIVER=gles2 fixes the perf issues

13:29 <mntirc> btw apparently there is a panfrost regression for a311d (mali g-57) that makes the full screen flicker on certain workloads, contributors bisected and reverted this commit to fix it https://source.mnt.re/reform/reform-debian-packages/-/merge_requests/85/diffs

14:27 <mntirc> now i have some funky bugs with firefox 135 on wayland mutter + latest git mesa + rk3588, where it often fails to finish drawing tiles, and those remain transparent, leaking parts of desktop through and messing with damage tracking (cursor trails)

21:21 <cphealy> mntirc: Unless I'm mistaken, the Amlogic A311D has a Mali G52 (Bifrost) and not the G57 (Valhall).

21:54 <mntirc> cphealy: you're right, my memory failed me there.

22:51 <cphealy> mntirc: regarding the patch that fix you pointed out above which reverts the addition of 32x8 AFBC, thinking out loud, I wonder if this is resulting in a path which forces GPU composition or bouncing between GPU and display plane composition. Historically, Panfrost has only supported 16x16 tiling when writing out AFBC for scanout. The GPU HW supports both 16x16 and 32x8 (and possibly others depending on generation). The

22:51 <cphealy> addition of 32x8 is to add support for HW platforms which only support 32x8 AFBC tile layout in the scanout plane HW.