Very poor CPU utilization with Progressive sampler in a particular scene

[Alex_M]

Hi,

I have a scene where CPU utilization is very poor with Progressive sampler. Please see screenshot below. It barely goes above 15% most of the time. I get a couple of short-lived 100% peaks every 30 seconds or so and then it goes back to ~15%. I've tested it on another workstation and it behaves the same. The scene fits in RAM just fine so I don't think it's swapping assets to disk.

What could be causing this? BTW, bucket sampler works fine and uses 100% of all 64 threads 100% of the time.

[Muhammed_Hamed]

Hi Alex,

Very odd, I tested progressive now with some scenes. It seems to be mostly fine with my 3990X
Does this happen often with your scenes?
We will need the scene if possible, or a simple version that reproduces the issue

Best,
Muhammed

[Alex_M]

I don't remember this happening often. I've just submitted a support ticked, as you suggested, with a download link for the scene. Ticket number is 42419. View and everything else is already set up. You just need to hit "Render".

[Muhammed_Hamed]

Thank you

We will investigate and report back