Linux 6.11-rc7 To Fix A "Massive Performance Regression" For AMD Graphics

[phoronix]

Phoronix: Linux 6.11-rc7 To Fix A "Massive Performance Regression" For AMD Graphics

Sent out today were the DRM fixes for 6.11-rc7 ahead of the Linux 6.11-rc7 kernel being released on Sunday. As usual most of the changes revolve around the AMDGPU and Intel i915/Xe drivers plus random fixes to the smaller drivers. There is one change though with the AMD Radeon graphics driver side worth highlighting to address a performance regression affecting recent kernels...

https://www.phoronix.com/news/Linux-6.11-rc7-AMDGPU-Fix

[WileEPyote]

I wonder if this is why Starfield performs so much better in WIndows for me. I easily lose 15-20 fps in big cities. from high 80s to high 90s to low 70s to low 80s

[stiiixy]

That's fucking terrible performance loss. Surely more than one person reported it since 6.6?

[fong38]

Wonder if this also impacts AMD iGPUs?

[ahrs]

That's fucking terrible performance loss. Surely more than one person reported it since 6.6?

If it's just the one game that happens to hit this by having VRAM cleared a lot then I can see why some people might have missed it. I wonder if AMD has a regression suite of some sort to avoid these problems occurring in the future? Maybe it's too difficult to run a GPU through a barrage of tests each new kernel version?

[jojo7887]

Recently switched from 6.6 to 6.10, didn't notice any regressions in any of the games I play

[Naib]

The performance loss was UNBEARABLE and cost me soo much MMR...
It wasn't just 6.10.x, but also Mesa itself ... I could tolerate 60fps but then I was hitting 10fps and had no idea why...

Enabling BAR in bios recovered my to 120fps while I waited for this patch

[ernstp]

That's fucking terrible performance loss. Surely more than one person reported it since 6.6?

It doesn't affect all games

[Gabbb]

Oh so it was not only my imagination!

[ms178]

If it's just the one game that happens to hit this by having VRAM cleared a lot then I can see why some people might have missed it. I wonder if AMD has a regression suite of some sort to avoid these problems occurring in the future? Maybe it's too difficult to run a GPU through a barrage of tests each new kernel version?

The problem has been known for a while, e.g. Cyberpunk 2077 also suffered from VRAM clearing. Kernel 6.10 was also a good example that AMD lacks in quality control, e.g. there was serious flickering in the upper half of the desktop. Such major bugs should have been noticed and fixed way earlier in the development process with some proper testing. At least the fix for the latter issue also fixed the VRR flickering at 165 Hz refresh rate I saw in several games for many months.