Corona 10 very low render performance

[j.nosh]

Hi,

just upgraded to 10. So far everything was fine. Just IR seemed to be rendering quite slow.

Then trying to render final in 4K. After 5h only 3 passes!!! 17K Rays/sample average!!!
Not very compex scene.

To track the reasons I tried a very simple test scene. Two cubes and Corona Sky/Sun.
500 Rays/sample in IR
Then downgraded to Corona 9. Same scene 100 Rays/sample only.

So something is wrong here I think and I will probably continue with CR9.

Any Ideas?

Thanks J


Some specs:
Cinema R21
AMD Ryzen Threadripper 3970X 32-Core Processor
Win 10 Pro
128GB RAM
SSD 980 PRO 1TB

[Beanzvision]

Hi there, are you able to test this with the V11 daily build as well and share your results?
https://forum.corona-renderer.com/index.php?topic=40461.0

[j.nosh]

ok thanks for the reply.
will try that and post update.

[j.nosh]

still the same :(

[Beanzvision]

And how about the hotfix 1 for V10? Can you test this too? https://corona-renderer.com/download

[j.nosh]

still the same.

I figured out that it got a bit better when using a Sky object with a 16k .hdr as a light source.
Rays/sample went down to around 200. which is still far away from your 24 :)

Also tried 9 hotfix 1 again. Here its much better still. But I observed that IR starts with around 20 Rays/sample and after Pass 10 it goes up to around 90, where it will stay then.

[j.nosh]

... for a more complex archviz scene (not IR) it means a difference of 500-600 Rays/sample in 9.1 compared to around 2000 Rays/sample in 10.0
which of course results in a rise in rendertime by at least 400%.

I also found the CPU having some sudden breaks in render power. this also happens with 9.1 thou.

Furthermore I saw that a certain material with some displacement caused 10.0 to even have much higher Rays/sample. I will try to find that material again and send a test scene.

My colleague runs the same system. just not watercooled but with a noctua fan, and he's having the same issues. If that might help to find the mistake.

[Beanzvision]

Even though your scene is simple, can you share it with us?

[clemens_at]

I have the same problem in max.
render performance is about 2-4 times slower compared to corona 9.
For me the performance takes huge hit when using triplanar map but that might just be coincidence.
Whatever it is, there is definitely something going on.
I opened a ticket as soon as I stumbled upon the issue, but so far nothing.
Let's hope it will be fixed soon.

[maru]

I have the same problem in max.
render performance is about 2-4 times slower compared to corona 9.
For me the performance takes huge hit when using triplanar map but that might just be coincidence.
Whatever it is, there is definitely something going on.
I opened a ticket as soon as I stumbled upon the issue, but so far nothing.
Let's hope it will be fixed soon.

Yes, I also thought about the issue you reported, but please keep in mind that in your case it is reproducible only on dual-cpu systems (tested on Xeons) and not with a single CPU.