Light Cache Incredibly slow

V-Ray for 3ds Max V-Ray for 3ds Max :: Issues
1

Hello,

I have an exterior scene, (HDRI, trees, grass, foliage, displacement) so it’s no breeze rendering it.

Anyway the LC is very slow, even when set to 100. This is a really bottle neck when it comes to testing, as even a small region can take much longer than I’d expect.

When I look at the CPU, they’re running at 25% max. Is this a RAM issue? Are there any work arounds? Trees and high poly objects are proxies, grass and foliage is forest pro.
I have 16gb ram, maybe an upgrade to 32 would do the trick, but I’m not a fan of throwing away money needlessly!

Dean

2

well.. how much of your ram are you using when rendering? what do you have the “dynamic memory limit” set to in the vray settings?

more ram is always better, and you will end up filling whatever you have. a scene as described would normally need more than 16gb.

3

If it is an exterior scene, then BF+BF might be better, but if the CPU is at 25% it might mean something else is a problem.What is your dynamic memory limit set to?

Best regards,
Vlado

4

Dynamic memory 14000

RAM is pretty full, task manager shows 15gb in use.

I wanted to use BF LC as it’s for an animation, so when loading the saved LC it isn’t so much a problem, just an issue when setting up the scenes. At the moment I have GI turned off to set-up lighting, which is my work around, but wanted to know if there’s anything else I could try.

Cheers,
Dean

5

Not really sure without taking a look at the scene. The 3ds Max bitmap pager is OFF, right?

Best regards,
Vlado

6

Yea it’s off, haven’t used it for years!

I seem to remember reading somewhere that LC is affected when RAM is full, is that correct? I’m starting to think it’s likely to be this, as other scenes are fine.

Dean

7

If the physical memory overflows, it might be a problem, yes.

Best regards,
Vlado