Low CPU usage during render

[hadacino]

Hi,
I have got a problem with rendering. My CPU usage is only about 4%!? My scene have got 30 mio. poly, displacement disabled.
Intel I7, 16 GB Ram. win 7 64bit.
Can you help me?
Thanks
Ondrej

[maru]

Hi, which version of Corona and 3ds Max is this?

Is this happening in any scene, or only in some specific one?
If it's just in one scene, any chance you have a photometric light somewhere?

[Artisticpixel]

I also have this issue on 1 of my scenes. 80 core Xeon and CPU usage is sitting at 11%.It is a small bathroom scene with 5 photo metric lights and 5 standard corona lights. Using the latest corona hotfix 2 on windows 7 pro and 3dsmax 2017.

Why would photometrix create an issue? It also renders fine on my other machine with 3ds max 2016

[Ondra]

Why would photometrix create an issue?

because

... 3ds max ...

[Artisticpixel]

That doesn't make sense if it works on 90% of the scenes?

[Ondra]

if that was the case, programming would be too easy ;). It is perfectly possible that the bug is triggered by some specific condition in the light, scene, or your computer. The vastly complex implementation of photometric lights just decides to lock all accesses to some of its resource (allowing only one thread to use it at once) for some reason. The results are disastrous. Most probably it is related to some UI parameter in photometric lights

[maru]

So the question here is: does removing all native 3ds Max standard/photometric lights fix the issue here?

[Artisticpixel]

I Have tried that, doesn't work. I have even tried a new scene with teapots and standard corona lights and although the usage goes up it doesnt go beyond 70%. Tried with one of my older scenes and they all hit 100%- the scene had ies lights in them. So there really is no understanding i for me. Before I went on to hotfix 2 it all seemed to work really well with no issues at all. The trouble machine is a dual E5-2698 v4, As i stated everything has been all fine until these past couple of weeks

[maru]

Sorry for a late reply, but is there a chance anyone with this issue could send the problematic scene to us?
The best form of contact is through this page: https://coronarenderer.freshdesk.com/support/tickets/new