Vray + Skatter Memory Usage (components vs groups)

Just came across an interesting issue (possibly bug?) and wanted to share. We were testing out Skatter for our workflow and kept running out of memory on our machines (32gb). It was during the processing components phase in vray: it would fill up as much RAM as possible, then kick over to vram, and finally just crash out. I thought that was sort of odd, because proxies don’t really need to all be held in memory.

After some testing this morning, I nailed it down to an issue of selecting a group vs a component as the skatter object. The built in library respects vray’s dynamic memory limit. And if I select a SketchUp component, works fine and respects the memory setting. However, the issue comes about when you select a group to skatter. For whatever reason, this causes the memory issue.

I’m guessing this boils down to whether the selected skatter objects are converted into vray proxies and then scattered or just scattered as is.

When you choose raw geometry (be it a component or group) to scatter, does it convert the object into a vray proxy first? Or does it copy it a bunch of times as is and then just show the resulting bounding box?

Skatter does not convert anything.
It just tells to Vray : “Take this object and copy it there, there and there (potentialy thousands of ‘there’)”

So the RAM issue you’re seeing is caused by how Vray handles groups over components. Unfortunatly I can’t do anything about this.
Other engines don’t have this issue (Thea, for instance, has very good memory usage)