User avatar
ayaromenok
Posts: 6
Joined: Mon Jul 01, 2019 6:57 pm
Contact: Skype

Re: Pi 4 - full specification of VideoCore 6

Tue Oct 29, 2019 8:59 am

Just want to leave here - my evaluation of VC6 performance (via GLES 3.1/ComputeShader from latest mesa 19.3-dev - see @jamesh post from 20191011) show good performance dependency from frequency only on few values: 500MHz(std), and downclocked 300MHz, 250MHz.

Values like 400, 600 and 700MHz don't show this dependency.

I believe, that VC6 synced with memory controller or some internal bus, but have no idea about values/steps. (and looks like not synced with ARM's cores). Or firmware-relative.

PS: looks like VC6 dependend from optimal workgroup size much more(almost linear between 100 and 256) than a JetsonNano's MaxwellGPU/nvidia drivers.
Last edited by ayaromenok on Tue Oct 29, 2019 8:06 pm, edited 2 times in total.

pagenotfound
Posts: 79
Joined: Mon Mar 14, 2016 12:44 pm

Re: Pi 4 - full specification of VideoCore 6

Tue Oct 29, 2019 12:11 pm

Can you please clarify your PS?

"hardly" and "much more" seem to contradict each other.

From Google translate:
"hardly" means "barely" or "scarcely" (used to qualify a statement by saying that it is true to an insignificant degree)

No offence, this meaning may be surprising to someone who is not a native speaker of English.

User avatar
ayaromenok
Posts: 6
Joined: Mon Jul 01, 2019 6:57 pm
Contact: Skype

Re: Pi 4 - full specification of VideoCore 6

Tue Oct 29, 2019 7:38 pm

pagenotfound wrote:
Tue Oct 29, 2019 12:11 pm
Can you please clarify your PS?
Pixel Shader(PS) just display input/output texture, used in Compute Shader(CS). While CS(probably, you ask about it) - simple box blur filter with different size(good for debugging).

And thank you for pointing on error on logic in sentence about WorkingGroups - I edit it to make it more clear.

laurent
Posts: 314
Joined: Thu Jul 26, 2012 11:24 am

Re: Pi 4 - full specification of VideoCore 6

Tue Oct 29, 2019 10:10 pm

jamesh wrote:
Wed Oct 16, 2019 11:58 am
Gavinmc42 wrote:
Wed Oct 16, 2019 11:55 am
Yep IP craziness.
Saw MS have opened up exFAT.
Already complaints about how messy it is :lol:

If BCM bring out a Vulkan blob for VC6 would we celebrate or complain?
Given past experience, complain. Because people are crazy..
Not sure it's because people are crazy. Complaints are may just louder.
(Give a try :mrgreen: )

trejan
Posts: 864
Joined: Tue Jul 02, 2019 2:28 pm

Re: Pi 4 - full specification of VideoCore 6

Tue Oct 29, 2019 10:35 pm

ayaromenok wrote:
Tue Oct 29, 2019 7:38 pm
Pixel Shader(PS) just display input/output texture, used in Compute Shader(CS)
PS at the end of your post looks more like a postscript than you talking about pixel shaders.

User avatar
ayaromenok
Posts: 6
Joined: Mon Jul 01, 2019 6:57 pm
Contact: Skype

Re: Pi 4 - full specification of VideoCore 6

Wed Oct 30, 2019 7:06 am

trejan wrote:
Tue Oct 29, 2019 10:35 pm
PS at the end of your post looks more like a postscript than you talking about pixel shaders.
Thank you. Looks like yesterday I didn't drink enough coffee :( Using "PS "and even full form of "PostScript" in GPU topic was very bad idea.

Technocolour
Posts: 54
Joined: Thu Jul 04, 2019 6:23 pm

Re: Pi 4 - full specification of VideoCore 6

Wed Oct 30, 2019 7:08 am

ayaromenok wrote:
Tue Oct 29, 2019 8:59 am
Just want to leave here - my evaluation of VC6 performance (via GLES 3.1/ComputeShader from latest mesa 19.3-dev - see @jamesh post from 20191011) show good performance dependency from frequency only on few values: 500MHz(std), and downclocked 300MHz, 250MHz.

Values like 400, 600 and 700MHz don't show this dependency.

I believe, that VC6 synced with memory controller or some internal bus, but have no idea about values/steps. (and looks like not synced with ARM's cores). Or firmware-relative.

PS: looks like VC6 dependend from optimal workgroup size much more(almost linear between 100 and 256) than a JetsonNano's MaxwellGPU/nvidia drivers.
Interesting, thanks!

Tangs
Posts: 1
Joined: Wed Nov 27, 2019 12:19 am

Re: Pi 4 - full specification of VideoCore 6

Wed Nov 27, 2019 12:21 am

Is there any progress on Vulkan drivers for the pi4 ?

Return to “General discussion”