Bug#1099841: gamescope: Noticeable performance regression in AMD Polaris

[Daltro Augusto]

Package: gamescope
Version: 3.16.1-1
Severity: normal
X-Debbugs-Cc: daltroaugusto at tutanota.com

The situation is occuring when I'm playing the game Red Dead Redemption 1, but it may happen in other games as well. I notice that when I'm playing the game (3D elements, mostly) everything is fine. However, if any HUD/UI element is overlayed, e.g. when I need to select other weapon while playing, I see huge FPS drops (90-ish to 50-ish), and the game stutters. When I play the same game without gamescope, things run fine. This issue didn't happen with the previous version of the package.

This 3.16 release of Gamescope introduced a major change for AMD polaris GPUs (like my Sapphire RX 570) that may be the reason of the issue. Before that version, we AMD users were obligated to use the "sdl" backend to run programs with gamescope, as the program gave us a "types/wlr_linux_dmabuf_v1.c:532: feedback_compile: Assertion `table_len > 0' failed." exception. Now, we seem to be obligated to use the default (wayland) backend, as if I try to run the game with the older sdl backend, I got the exact same exception that was outputted when I tried to use wayland backend, in the previous versions.

So, I would expect to: be still able to run the older backend; or to at least not have noticeable performance issues due to this new backend/due to the latest updates.

-- System Information:
Debian Release: trixie/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 6.13.6-1-liquorix-amd64 (SMP w/8 CPU threads; PREEMPT)
Kernel taint flags: TAINT_CPU_OUT_OF_SPEC
Locale: LANG=pt_BR.UTF-8, LC_CTYPE=pt_BR.UTF-8 (charmap=UTF-8), LANGUAGE=pt_BR:pt:en
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages gamescope depends on:
ii  libavif16             1.1.1-1
ii  libc6                 2.40-7
ii  libcap2               1:2.66-5+b1
ii  libdecor-0-0          0.2.2-2
ii  libdisplay-info2      0.2.0-2
ii  libdrm2               2.4.124-1
ii  libeis1               1.3.901-1
ii  libgcc-s1             14.2.0-17
ii  libliftoff0           0.5.0-1.1
ii  libluajit-5.1-2       2.1.0+openresty20250117-2
ii  libpipewire-0.3-0t64  1.2.7-1+b2
ii  libpixman-1-0         0.44.0-3
ii  libsdl2-2.0-0         2.32.2+dfsg-1
ii  libstdc++6            14.2.0-17
ii  libwayland-client0    1.23.1-3
ii  libwayland-server0    1.23.1-3
ii  libwlroots-0.18       0.18.2-3
ii  libx11-6              2:1.8.10-2
ii  libx11-xcb1           2:1.8.10-2
ii  libxcb1               1.17.0-2+b1
ii  libxcomposite1        1:0.4.6-1
ii  libxcursor1           1:1.2.3-1
ii  libxdamage1           1:1.1.6-1+b2
ii  libxext6              2:1.3.4-1+b3
ii  libxfixes3            1:6.0.0-2+b4
ii  libxi6                2:1.8.2-1
ii  libxkbcommon0         1.7.0-2
ii  libxmu6               2:1.1.3-3+b4
ii  libxrender1           1:0.9.10-1.1+b4
ii  libxres1              2:1.2.1-1+b2
ii  libxtst6              2:1.2.5-1
ii  libxxf86vm1           1:1.1.4-1+b4
ii  xwayland              2:24.1.6-1

Versions of packages gamescope recommends:
ii  seatd  0.9.1-1

Versions of packages gamescope suggests:
ii  libcap2-bin     1:2.66-5+b1
pn  pipewire-audio  <none>

-- no debconf information