System VERY unresponsive while rendering

[akos_kiss]

Hi All!

Recently i've noticed that when rendering with v-ray my whole computer "freezes up" and becomes really slow and unresponsive. Mouse movement is lagging, gui is slow to update and laggy. Basically when i start rendering my whole system becomes unusable. This is to the point that i can't stop the rendering process because the vfb gui doesn't register the mouse clicks on the stop rendering button.

For most of the c4d users - i think - this is a new behaviour.

I'm not sure what to do because low thread priority is enabled and for the past 3 years I never had this issue. I could easily use c4d and animate or do some light modelling, use ps, or ae, brows the web, watch videos etc. The adaptive or low thread priority was on of the most useful and best check boxes. I dont want to lower the available thread count in c4d. i just want the adaptive thread priority to work as it did for the past years.

This issue has been present on a few machines for the past few weeks now. Only when rendering with vray (cpu mostly, but sometimes gpu). Anyone else experiencing these lags and slowdowns lately?
I've experienced this with bot vray 5 and 6 (c4d r25 and 2023) Cpu rendering and gpu rendering (the latter is an expected behaviour because of the gpus).
This is immensely frustrating.

Most of the machines are high spec ie. Threadripper machines 32 and 64 core, 256gb of ram, 30 series gpus all nvme ssd. windows 10 pro latest everything. latest nvidia studio drivers. And this is still an issue that appeared in the recent weeks.

Anyone has any ideas what could've caused this issue?

[deyan.hadzhiev]

Hi akos_kiss, thanks for the report. We are aware of this issue and we are still investigating what might have caused this.

It was already mentioned that this is also observed in V-Ray for 3ds Max with similar hardware configurations in this forum post.

We are sorry for the inconvenience and will try to find the cause of this issue, which is definitely a regression since V-Ray 5.

[RwVision]

I can only say, that I also experience some lags, especially when the rendering is starting - working on threadripper 3960X. But I also experienced this in V5, just V6 seems to handle it worse.

[haniel1107]

Hello,
I am experiencing the same, but additionally it takes sometimes 10 min before the first frame starts to render. Of course it depends on the scene and amount of objects, but it seems sometimes way to long.
But Interactive is reacting and starting normal.
Latest Vray6 build, Win11, Threadripper 3990x, 128GB, CPU rendering.

[RwVision]

Bumping this up, as I'm just rendering a simple scene animation, and every few frames I get this heavy entire system slowdown on render start. Really annoying :/

[klex167]

Same here. My mouse pointer is almost unresponsive and I can't access other tools. Using the windows explorer ist sometimes not possible.

[deyan.hadzhiev]

Hi all, as we are still investigating the problem. To ensure this is not intended behavior - can you confirm that you have the "Adapt Thread Priority" setting enabled?


For non-interactive renders, V-Ray is reading this option and if it is disabled, threads are intentionally given higher priority, meaning that the slowdowns are expected (when the parameter is disabled).

[haniel1107]

Hi all, as we are still investigating the problem. To ensure this is not intended behavior - can you confirm that you have the "Adapt Thread Priority" setting enabled?

...

at my, it is activated...

[klex167]

Yes, it's enabled.

[ivaylocg]

Does this happen with ANY scene you try to render? Can you please try to create a simple basic scene, which renders for a few minutes - does the issue reproduce with it? I am trying to establish if this is scene dependent or not.

[haniel1107]

Does this happen with ANY scene you try to render? Can you please try to create a simple basic scene, which renders for a few minutes - does the issue reproduce with it? I am trying to establish if this is scene dependent or not.

Hi, yes almost every scene, but as more complex the render calculation as more...

Here is super a simple scene... It doesn't matter if progressive or bucket.. You need one or two minutes and the pc will start stucking... There a seconds in between, where the pc reacts normal..

Latest C4D 2023 / Win11 Threadripper 3990x / CPU rendering 128 MB Ram / RTX 3090 / Latest nightly Vray6

[tsvetomira.girginova]

Thank you for the provided scene, haniel1107 !
Highly appreciated.

We will test it and share what is experienced on our Threadripper 3990x with it.

Best regards,
TS

[sirio76]

What happens if you disable a few cores in the C4D preferences?

[akos_kiss]

deyan.hadzhiev Yes i have adapt thread priority enabled on 9 machines and all of them are sluggish.

sirio76 If i set a custom number of render thread the machine works better but the whole machine is still lagging. (i.e. 64 thread cpu and if i set the render threads to 58 it works a bit better but the GUI is still lagging) But this is a workaround and not a solution The adaptive thread priority worked like a charm for years, so i just want it to work again

[haniel1107]

deyan.hadzhiev Yes i have adapt thread priority enabled on 9 machines and all of them are sluggish.

sirio76 If i set a custom number of render thread the machine works better but the whole machine is still lagging. (i.e. 64 thread cpu and if i set the render threads to 58 it works a bit better but the GUI is still lagging) But this is a workaround and not a solution The adaptive thread priority worked like a charm for years, so i just want it to work again

agree... should work normal, but also like to mention, the render speed is really good,.. would be nice to keep the performance