Rendering a empty scene uses 2.3gb vram.

mats76

I noticed that if I open daz studio and hit the render button the vram usage goes up from 369mb to 2.3gb, is that normal vram usage for an empty scene?

 

Vram usage (gpu-z)

Just windows 125mb

Daz studio opened 369mb

rendering a empty scene 2.3gb

 

I am using win7 64bit and a Gtx 1080ti..

 

Thanks in advance

Richard Haseltine

How is the scene lit - with an HDRI?

mats76

Richard Haseltine said:

How is the scene lit - with an HDRI?

Using the standard hdri, but I just tried it with no hdri and still uses 2.3gb vram.

Richard Haseltine

For me it jumps to 1.5GB, so still a big increase (I think the actual IRay code gets uploaded, regardless of content, though at the same time I was able to render a simple nide on my old 1GB card when Iray was new).

mats76

Richard Haseltine said:

For me it jumps to 1.5GB, so still a big increase (I think the actual IRay code gets uploaded, regardless of content, though at the same time I was able to render a simple nide on my old 1GB card when Iray was new).

Thanks for checking.

 Weird thing though, I did a cpu only render and the ram memory usage only increased with 0.4GB when rendering the empty scen. Should it not be an equally large memory usage to the ram in cpu mode as the vram in gpu mode when the IRay code gets uploaded?

ramon73

Old topic, but my VRAM usage in an empty scene is really high lately as well. After starting up DS it is already using 3GB, it never used to be that high. Is it because I have a lot more assets installed now? I only have 8GB to work with so having 3GB used up already kinda sucks.

crosswind

Iray Render Engine will consume appr. 2.1 - 2.4  GB VRAM even if you just preview or render an empty scene... You may observe the VRAM used with GPU-Z.. This part of 'Engine Consumption' will be only released after a DS instance is completely closed.

 

PerttiA

The process needs "Working Space", which by default takes 1.9GB's of VRAM

ramon73

crosswind said:

Iray Render Engine will consume appr. 2.1 - 2.4  GB VRAM even if you just preview or render an empty scene... You may observe the VRAM used with GPU-Z.. This part of 'Engine Consumption' will be only released after a DS instance is completely closed.

 

I do always have iRay viewport open, but it never was 3GB in an empty scene. To bypass this problem right now I create the scene first and then save it with texture shaded viewport setting. If I restart DS then and loads with the texture shaded viewport setting DS only uses 1 GB VRAM. If I change to iRay viewport then it jumps to 3 GB. If I go back to texture shaded it still stays at 3 GB VRAM, it doesn't dump the VRAM usage.

crosswind

The engine consumption just starts when you iray preview or iray render. It's irrelevant to other Draw Styles. I mentioned that it would be only released after you close DS...

Padone

As I understand it, iray is very "lazy" to handle vram, that means more memory than needed is allocated, and also kept allocated when not used. So what you see is not the "real" vram necessary for the scene. This may also depend on the iray and drivers versions.

PerttiA

Padone said:

As I understand it, iray is very "lazy" to handle vram, that means more memory than needed is allocated, and also kept allocated when not used. So what you see is not the "real" vram necessary for the scene. This may also depend on the iray and drivers versions.

Where do you get that idea? 

There is nothing "lazy" about the usage of VRAM when rendering Iray

Padone

In computer science, "lazy memory allocation" has another meaning than what you probably imagine. It's as I described above and that's common for advanced programming languages. Iray seems to do the same.