Platform: HSW mobile
Bug detailed description:
Unigine-heaven performance reduce by 12% with gnome-session on HSW mobile, reduce by 6.5% on HSW desktop.
It’s Mesa regression. By bisected, show that 2dad1e3a is the first bad commit.
Author: Matt Turner <firstname.lastname@example.org>
AuthorDate: Wed Feb 12 11:00:46 2014 -0800
Commit: Matt Turner <email@example.com>
CommitDate: Tue Feb 17 20:44:09 2015 -0800
i965/fs: Add pass to combine immediates.
total instructions in shared programs: 5885407 -> 5940958 (0.94%)
instructions in affected programs: 3617311 -> 3672862 (1.54%)
... but will allow us to always emit MAD instructions.
Reviewed-by: Kenneth Graunke <firstname.lastname@example.org>
Please see Xrog.0.log.
3, vblank_mode=0 ./bin/heaven_x64 -video_app opengl -data_path ../ -sound_app null -engine_config ../data/heaven_4.0.cfg -system_script heaven/unigine.cpp -video_mode -1 -video_fullscreen 1 -extern_define PHORONIX,RELEASE -video_width 1920 -video_height 1080
Created attachment 113936 [details]
> by 12% with gnome-session on HSW mobile
This is GT3e.
> by 6.5% on HSW desktop
This is GT2.
Same commit also regresses PSPom test a bit and clearly improves GfxBench ALU test, GpuTest volplosion & Piano tests, maybe a bit also PSBump2.
On GT3e we see much larger effect on Heaven (our GT3e is diffferent version). We're also seeing the effect on all platforms, not just on HSW or GT3e, although on others it's much smaller than with (HSW) GT3e.
Because there's both performance increase & decrease, commit doesn't need to be reverted.
Matt, this regression is still visible in Heaven performance (Martin has graph that show how the Heaven perf drops on BDW and it keeping down ever after).
Do you have some plan on how the get previous performance back, without regressing test-cases which that commit improved?