[Nouveau] glmark2: high CPU usage - DRI3 & modeset

[poma]

On 07.04.2016 14:51, Karol Herbst wrote:
> did the test result changed in any way? Maybe the DRI2 run was vsynced and the
> DRI3 not?
> Nouveau has a pretty high cpu usage in general, because it usually busy waits on
> fences (I think? not sure where it was exactly that nouveau is busy waiting)
> 
>> poma <pomidorabelisima at gmail.com> hat am 7. April 2016 um 13:56 geschrieben:
>>
>>
>>
>> $ glmark2
>> =======================================================
>>     glmark2 2014.03
>> =======================================================
>>     OpenGL Information
>>     GL_VENDOR:     nouveau
>>     GL_RENDERER:   Gallium 0.4 on NV98
>>     GL_VERSION:    3.0 Mesa 11.2.0
>> =======================================================
>>
>>
>> /etc/X11/xorg.conf.d/nouveau.conf 
>> Section "Device"
>>   Identifier  "gpu0"
>>   Driver      "nouveau"
>> EndSection
>>
>> $ ps -C glmark2 -o cmd,pcpu
>> CMD                         %CPU
>> glmark2                     16.2
>>
>> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>
>> /etc/X11/xorg.conf.d/nouveau.conf 
>> Section "Device"
>>   Identifier  "gpu0"
>>   Driver      "nouveau"
>>   Option      "DRI" "3"
>> EndSection
>>
>> $ ps -C glmark2 -o cmd,pcpu
>> CMD                         %CPU
>> glmark2                     86.4
>>
>> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>
>> /etc/X11/xorg.conf.d/modeset.conf 
>> Section "Device"
>>   Identifier  "gpu0"
>>   Driver      "modesetting"
>> EndSection
>>
>> $ ps -C glmark2 -o cmd,pcpu
>> CMD                         %CPU
>> glmark2                     94.5
>>


'vblank_mode=0 glmark2' makes no difference.

A -fence- as a sync object?
https://www.opengl.org/wiki/Sync_Object#Fence