Company of Heroes 2 performance regression of ca. 50% on recent Mesa builds (tested on R600 and RadeonSI)
Company of Heroes 2 is available as a Feral Linux port on Steam (sometimes given away for free). Around half a year ago, I noticed a big performance regression of around 50% using the built-in benchmark on recent Mesa versions since late 19.1 versions. Unfortunately I cannot be more specific or bisect, but I can confirm that the performance is still bad with a recent Mesa 20 / LLVM 9 git build from 20th December 2019. The distribution used is openSUSE Tumbleweed.
I've noticed this regression on three very different configs, a Sandy Bridge laptop with a 6770M, and two desktop PCs, one Ivy Bridge 3770 system with an RX580 and a system with a Ryzen 2600 and a Vega 56. The laptop went down from around 20 fps on low settings to 10 fps. The Vega system went down from mid 40s to 20s fps on medium/high settings (which is also way slower than on Windows were I get mid 70s fps on the highest settings).
I would be glad if someone could look into it.