[Mesa-dev] [BUG] Large slowdown with RADV / Warcraft with latest Mesa from Git.

[Michel Dänzer]

On 2021-01-08 6:16 p.m., Michel Dänzer wrote:
> On 2021-01-08 5:54 p.m., Chris Rankin wrote:
>> Hi,
>>
>> I've just noticed a large drop in FPS (from 60 down to 15) when 
>> playing World of Warcraft with the latest Mesa from Git.
>> A quick git bisect has identified this commit:
>>
>> 4292fb2139282e6906d4ad2a8be2fd81ed7ca8af is the first bad commit
>> commit 4292fb2139282e6906d4ad2a8be2fd81ed7ca8af
>> Author: Michel Dänzer <mdaenzer at redhat.com>
>> Date:   Mon Dec 21 15:41:56 2020 +0100
>>
>>      wsi/x11: Use PresentOptionAsync for MAILBOX present mode with 
>> Xwayland
>>      This allows Xwayland to forward buffers to the Wayland compositor 
>> ASAP
>>      for fullscreen / undecorated windows, which in turn allows true 
>> mailbox
>>      behaviour in the Wayland compositor.
>>      Without this, Xwayland has to emulate the mailbox behaviour itself,
>>      which it cannot do as well as the Wayland compositor by design.
>>      Reviewed-by: Bas Nieuwenhuizen <bas at basnieuwenhuizen.nl>
>>      Part-of: 
>> <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8197>
>>
>>   src/vulkan/wsi/wsi_common_x11.c | 7 +++++++
>>   1 file changed, 7 insertions(+)
>>
>> I am playing WoW with this release of Wine:
>>
>> wine-6.0-0.4rc4.fc33.x86_64
>>
>> And this version of DXVK:
>>
>> wine-dxvk-1.7.2-3.fc33.x86_64
>>
>> Curiously, I am using Xorg rather than Wayland, and so don't 
>> understand why this commit should affect me.
> 
> Does the attached patch fix it?

Actually, that would only make a difference if your X server didn't 
support the RANDR extension, which seems unlikely.


I found two more bugs: 
https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8393

Still not sure how that could have caused a drop from 60 to 15 fps, but 
hopefully this will fix it.


-- 
Earthling Michel Dänzer               |               https://redhat.com
Libre software enthusiast             |             Mesa and X developer