Dynamic Memory Limit question

[tricky]

We have a very complex scene that uses around 6GB memory just to open. The main Max file is just a holder for several XREF scenes.

My machine has 64GB RAM in it, but my colleagues has only 16GB. I don't understand how setting a value for Dynamic Memory Limit actually limits the memory usage when he renders. Regardless of what he sets, it always uses 20-25GB of physical and virtual memory.

On my machine, I set this figure to zero and it just uses 24GB or so to render. No problem.

What should I be putting in here for machines with less RAM to help prevent crashes etc?

(at the moment, we are using a simple Universal setup for rendering with LC/BF)

[glorybound]

My understanding is, the weakest machine is the weak link, and it needs to be set for the weakest link.

[Morbid Angel]

You have to understand that dynamic memory is not a straight up number that you can put in as a cap. For example, some geometry is static, it cannot be capped by dynamic limit, same goes for textures. You can have 15 gb worth of textures alone and dynamic limit wont get you anything. If you have a mixture of dynamic and static geometry, first look at how much static geo/maps take before drawing conclusion on what your dynamic memory limit should be.

[tricky]

You have to understand that dynamic memory is not a straight up number that you can put in as a cap. For example, some geometry is static, it cannot be capped by dynamic limit, same goes for textures. You can have 15 gb worth of textures alone and dynamic limit wont get you anything. If you have a mixture of dynamic and static geometry, first look at how much static geo/maps take before drawing conclusion on what your dynamic memory limit should be.

How do I establish the memory needed for textures/geometry?

To give you a flavour of the project, this is it:-

[Morbid Angel]

There is no set rules for how to go about these things. Your render looks detailed which means its probably high on the poly count. If this is non instanced geo, non vray proxy it will result in high memory foot print. Converting some of that to vray proxies will help.

For the textures, if you have large maps and many of them, the ram will go high very fast. So you have to ensure your maps are either not too high res (if you have many) or that you are using tiled textures like tiled exr or tx.

[tricky]

There is no set rules for how to go about these things. Your render looks detailed which means its probably high on the poly count. If this is non instanced geo, non vray proxy it will result in high memory foot print. Converting some of that to vray proxies will help.

For the textures, if you have large maps and many of them, the ram will go high very fast. So you have to ensure your maps are either not too high res (if you have many) or that you are using tiled textures like tiled exr or tx.

It certainly is quite highly detailed. Some of it is instanced, but much of it isn't. It seems rather crude and hit-or-miss to have to go in and change certain things into vrayproxies to help with ram usage. Shouldn't VRay be able to break things up into more manageable chunks internally, on the fly (or per bucket or something of the sort)? I'm obviously oversimplifying here!

I think the texture setup is quite simple really.

[vlado]

Shouldn't VRay be able to break things up into more manageable chunks internally, on the fly (or per bucket or something of the sort)? I'm obviously oversimplifying here!

I don't see how. Proxies help to keep the geometry out of your 3ds Max scene and load it only during rendering. However if the geometry is already there in your scene as a regular 3ds Max object, V-Ray can't just go and delete it (although it does attempt to share as much data as possible with 3ds Max). V-Ray is pretty smart about how to spend the rendering memory, but in a typical scene, the larger part of the RAM is actually taken up by 3ds Max and the scene data. Removing stuff from your 3ds Max scene to only load it for rendering (f.e. converting to proxies or using VRayHDRI) is something that only you can do.

Best regards,
Vlado