Significant stuttering on Linux

[kaapio]

Your system information

• System information from steam (Steam -> Help -> System Information) in a gist:
  • https://gist.github.com/kaapio/78b9ec034dc1a49d51374b9277ffddd8
• Have you checked for system updates?: [Yes/No]
  • Yes
• Are you using the latest stable video driver available for your system? [Yes/No]
  • Yes
• Have you verified the game files?: [Yes/No]
  • Yes

Please describe your issue in as much detail as possible:

Despite a fresh install and powerful new hardware (RTX 4080S + i9-13900k), I am experiencing high amounts of stutter during gameplay and main menu. The stuttering seems to be related to rendering hero models, because the main menu stutter completely disappears when the game is launched with +map_enable_background_maps 0 in the launch options.

The FPS reported by the game itself wildly bounces between 70 and 110, but the stutters are definitely much worse than th at. The issue persists in games and in demo hero even when the camera is moved off-map such that there is effectively nothing on the screen.

Here's some things that I tried but did not affect the issue to the naked eye:

• Changed graphics settings and the rendering resolution to the lowest options
• Launch flags -vulkan_disable_steam_shader_cache and -vulkan_disable_graphics_pipeline_library
• Gamemode with default options
• Different WM/DEs (i3, GNOME, KDE)

I also using different Proton versions, but the game crashed on startup with all of the latest versions (out of scope for this ticket anyway)

I would be happy to provide any log files or other config information, if it would be useful.

Steps for reproducing this issue:

1. Launch Dota 2
2. Observe stutter in the main manu, demo hero and regular gameplay

[kaapio]

I have been tinkering with the issue and I finally found out a meaningful improvement, which could be useful in pinpointing the issue.

I switched from the default linux kernel to linux-zen, which caused the stutter to decrease massively, but not completely disappear. The game is now playable for me, but still far from being as smooth as my Windows experience was on my previous machine.

EDIT: With the linux-zen kernel I am also able to launch the game with Proton Experimental again, which produces a butter-smooth experience! This way, 'VAC is unable to verify that my machine is secure' and thus I cannot access the matchmaking, but demo hero and anything I can try is a solid 144fps experience!

[kaapio]

This issue seems to be fixed with the Crownfall update. The perfromance is still a tad behind the DirectX version, but it is very close!