Dynamic subdivision not working with older scene?

[SonyBoy]

I'm re-rendering an older scene with Vray 6 and am noticing that dynamic subdivisions during renders into the VFB are non-existent.

Is this expected behavior? The scene was definitely created prior to dynamic subdivs being introduced.

[vladimir_krastev]

Hi, thanks for posting. Are you talking about adaptive bucket splitting or about dynamic geometry subdivision?
Dynamic geometry subdivision has been around since very early versions of V-Ray while adaptive bucket splitting has been developed relatively recently.
Adaptive bucket splitting has nothing to do with the V-Ray version the scene was built with. Dynamic bucket splitting will be disabled if you are using distributed rendering.

[SonyBoy]

I'm talking about adaptive bucket splitting. I am using DR so I guess that's why it isn't working, although I would have sworn I've seen it in action previously when using DR. My memory must be wrong. Are there any plans to make it compatible with DR at any point? This would be incredibly useful.

[SonyBoy]

However, I've also noticed that this adaptive bucket splitting sometimes seems to work and sometimes doesn't, regardless of whether I'm using DR. Does it depend on CPU generation or other hardware specs? Otherwise, why would it sometimes work and sometimes not, even on the same scene file?

[vladimir_krastev]

It depends on the scene. For instance a opaque refractive material will take a lot of time to render and if all the rest is done (lets say we have only one object with a heavy material) but only a few buckets struggle to complete this object then they are split so that more CPU cores can join rendering instead of idling.