I have multiple lights blinking in my animation.
Some instanced, other manually placed.

And for some reason one same blinking from time to time randomly on same render pass..
On each interior rendering pass there is one (but not the same) that is blinking.



Project are heavy (many assets and textures) and on we also notice rendering time aberration :
- Time mutiplied by 2 to 10 when there too many objects are in the scene and even if there are no rendering influence
when I hide a scatter of cars for example render take 4min (instead of 40min), same thing if I hide one other. And both have no direct incidence on rendering image. But scene was a bit lighter in memory.

- Time mutiplied by 2 to 10 on still image at big resolution (5K). Render image tiles in 4 or 16 help but not always.
one piece : 12h15min
4 tiles : 2h25min = (21min + 2h22min !!! + 22min + 20min)
16 tiles : 1h40min = (6 + 6 + 6 + 5m30s + 8 + 6 + 6 +7 + 8 + 6 + 6 + 7 + 6 + 6 + 6 + 6)

Anyone experience any of those bad things ?
Is Karma XPU is really production ready ?

I can confirm all of this, helping out on this project and it is a pain.
One of my machines is regularily failing during rendering (ryzen 5950x, 128GB ram, 2xx4090).
During rendering GPU just fails and stop being used then other one as well.. Managed to keep things working only by pruning anything that is not directly visible to camera.
Really wondering if anyone else is running in similar issues? Or we hit some wierd combination of too many assets or something..

>

julca
I have multiple lights blinking in my animation.
Some instanced, other manually placed.
And for some reason one same blinking from time to time randomly on same render pass..
On each interior rendering pass there is one (but not the same) that is blinking.

I see a bug regarding the "large (ie 5K) render being slower than tiled" issue has been submitted thanks.

But have you submitted a bug regarding the flickering lights?
It'll be near impossible for us to debug this without a repro scene. Is it possible you could submit a bug with a repro scene that exhibits the flickering issue? (eg just the lights with some proxy geo)

Mirko Jankovic
One of my machines is regularily failing during rendering (ryzen 5950x, 128GB ram, 2xx4090).
During rendering GPU just fails and stop being used then other one as well

What error messages do you get regarding the GPU failings? Can you post a render log?

I have photo that I took to share with Julca, also today 2 other machines had same crash as well. Actualy not a crash, after this error GPU just stop being used for rendering and only CPU continues.

brians
Is it possible you could submit a bug with a repro scene that exhibits the flickering issue?

Project link is shared on same bug than the one of "5K" (same scene) with multiples e-mails with multiple video record illustrate the problem on multiple pass.

For now I havn't succes to reproduce it in a simple scene.
I have also have a deadline and we do our best to deliver project in time.

julca
For now I havn't succes to reproduce it in a simple scene.
I have also have a deadline and we do our best to deliver project in time.

Ok, thanks for what you've sent already.
We'll have a look and get back to you in the coming days.

Hello @brians,
We're still on same kind of project (another) with short deadline and got same light blinking and rendertime exploding..
Support won't project because too heavy... so it would take a time to create same bug in a lighter project... Isn't your job ?

Note that once GPU vram is full, GPU card become useless and rendertime jump by a factor of 4 here.
A 4090 comp become equivalent to a 2080ti comp here..

And it also make 2080ti even more useless.

In brief you have a big problem on the memory management for karma XPU.
It force us to optimize scene and hide as much thing we can to pass bottom the bar of GPU vram.
Feel like working for realtime here

Are you aware of that ? If that somethings in your radar for improvements or an unsolvable technical limitation.