lima: 3D perfomance issue
I experience heavy performance differences between lima and mali drivers in 3D rendering.
The Qt application in the videos below is based on Qt example.
Setup:
- Hardware: Xilinx ZynqMP with Mali400 (600MHz)
- Linux: 5.10
(due to custom hardware, moving to the latest kernel in order to test the latest lima version is extremely complicated. However, I went through the commits history and I haven't seen changes which could impact performance. I only cherry-picked this commit. On request, I could try to cherry-pick others) - Mesa: 21.2.4 (the same behaviour quickly confirmed with 22.1)
- Qt 5.15.3 with EGLFS_KMS
Lima:
lima
As presented in the video, with the Lima driver, the rendering is slower than with Mali making it unusable. There is also a flickering issue in the graph and a jumping cursor problem (Mali doesn't provide hardware accelerated cursor as well).
I also noticed that with Lima, due to low performance, the application changes mode:
from qt.scenegraph.general: threaded render loop
to qt.scenegraph.general: animation driver switched to timer mode
which is not the case with Mali.
I know that Mali driver has another issue and, although it's the same code, it doesn't render axis labels.
Edited by Adrian Fiergolski