AMD graphics performance regression in 4.15 and later
From: Jean-Marc Valin
Date: Thu Apr 05 2018 - 20:31:05 EST
I noticed a serious graphics performance regression between 4.14 and
4.15. It is most noticeable with Firefox (tried FF57 through FF60) and
causes scrolling to be really choppy/sluggish. I've confirmed that the
problem is also there on 4.16, while 4.13 works fine.
After a bisection, I've narrowed the regression down to this commit:
Author: Christian KÃnig <christian.koenig@xxxxxxx>
Date: Thu Jul 6 09:59:43 2017 +0200
drm/ttm: add transparent huge page support for DMA allocations v2
Some details about my system:
Distro: Fedora 27 (up-to-date)
Video: MSI Radeon RX 560 AERO
CPU: Dual-socket Xeon E5-2640 v4 (20 cores total)
RAM: 128 GB ECC
As a comparison, when running Firefox with 4.15 on a Lenovo W540 laptop
(with Intel graphics only) the responsiveness is much better then what
I'm getting on the Xeon machine above with the Radeon card, so this
really seems to be an AMD-only issue.
Any way to fix the issue?