Bug 101278

Summary:	Severe slowdown on Shadow of Mordor between 17.1.0 and 17.1.1
Product:	Mesa	Reporter:	nagrigoriadis
Component:	Drivers/Gallium/radeonsi	Assignee:	Default DRI bug account <dri-devel>
Status:	RESOLVED FIXED	QA Contact:	Default DRI bug account <dri-devel>
Severity:	normal
Priority:	medium
Version:	17.1
Hardware:	x86-64 (AMD64)
OS:	Linux (All)
Whiteboard:
i915 platform:		i915 features:
Attachments:	Patch making the conditions even tighter Alternative patch

Description nagrigoriadis 2017-06-02 10:32:55 UTC

Shadow of Mordor slowed down significantly for me on my notebook between Mesa 17.1.0 and 17.1.1

My system:
Gentoo Linux 64-bit
Dell Precision M4700
Intel i7-3720QM quad-core
16 Gig RAM
AMD FirePro M4000 (Cape Verde, 512su, 1GB DDR5 RAM, 675Mhz)

I then did a bisect to find the commit where the slowdown happened (used the built-in benchmark tool manually, some custom medium-low settings):
35ec26bb00536639b9571f31d8e3f2bcbcfc32fb 30.31fps
ad3b5b7f5f7590fd4359ea3483e2309e4cebc472 18.12fps

So the commit that causes the big slowdown:
https://cgit.freedesktop.org/mesa/mesa/commit/?h=17.1&id=ad3b5b7f5f7590fd4359ea3483e2309e4cebc472
seems to be specific to SI, but appears to fix an issue in tessellation.
I double-checked, and tessellation is off in the game settings, so I'm surprised this caused a performance difference.

Comment 1 nagrigoriadis 2017-06-02 10:37:00 UTC

Apologies, I forgot some important related details:

I'm on kernel 4.11.1-gentoo right now, but observed the same on 4.10.8
libdrm-2.4.80
llvm-4.0.0-r2
xorg-server-1.19.3
xf86-video-ati-7.9.0
using the "radeon" kernel module.

Comment 2 Nicolai Hähnle 2017-06-12 14:54:36 UTC

Should be fixed in master since commit 391673af7a.

Comment 3 nagrigoriadis 2017-06-13 08:53:14 UTC

Thanks Nicolai for your quick action.

I first built the latest git master: 2e28e8b199abab76fa9509d3247b44a2cb31921d
But everything was green, and the game would crash in the menu.

I then built 391673af7ad1565a5f6ac8fc2f8c9fcdd1fe9908
And it worked, but performance is still in the regressed state :-(

The thing is, tessellation was off this whole time.

Please advise?

Comment 4 Nicolai Hähnle 2017-06-14 10:36:42 UTC

Created attachment 131949 [details] [review]
Patch making the conditions even tighter

Odd. Maybe the game lies to you about tessellation being off? Anyway, could you please try the attached patch?

Comment 5 Nicolai Hähnle 2017-06-14 10:37:31 UTC

Created attachment 131950 [details] [review]
Alternative patch

If the patch from the previous comment works, could you please also try this patch as an alternative? Thanks!

If neither work, could you please provide an apitrace?

Comment 6 Timothy Arceri 2018-09-09 23:07:46 UTC

No reply so assuming fixed and closing.

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