Changing bucket size during IPR render causes 100% memory usage, C4D unresponsive.

[AJUKking]

C4D R21.207

C4DtoA 3.0.4 [98f64989]
Arnold core 6.0.3.1

I can only reproduce this issue in a certain scene I have: Google drive link

Run the IPR, increase the bucket size to something large like 250, then immediately try to set it back to default. Memory usage will quickly be eaten up to 100% and C4D will become unresponsive.

[peter.horvath6V6K3 · Accepted solution]

I guess it's expected. Memory usage depends on the number of render threads, buckets size and samples. Increasing the bucket size from 64 to 256 means that each render thread will be dedicating 16x more memory to the samples/framebuffer.