Ubuntu 20.04 LTS vs. Linux 5.9 + Mesa 20.3-devel Radeon Graphics Performance
For Batman: Arkham Knight running under Linux at both 1080p and 1440p there was a few frames per second increase when moving to the latest driver stack.
For Deus Ex: Mankind Divided running on RadeonSI Gallium3D the Navi graphics cards saw slightly better performance while Vega regressed slightly.
Dota 2 with Vulkan was seeing some very slight gains in performance on Linux 5.9 and Mesa 20.3-devel.