Vray7 constant crashes with displacement and instances

[mori4h]

I'm trying to instance a few objects (3 megascans rocks) via scatter to points and i can't manage to make it work. Here's what i tried:

1-Have the objects live in the scene, packed, scattered » render without displacement » OK.
2-Have the objects live in the scene, packed, scattered » render with displacement » Stuck at "Compiling geometry..." » can't cancel, have to restart Houdini. (If i wait long enough it says "Error: Exception in CORE: Internal error."
3-Have the objects cached to abc, scattered » render without displacement » renders but then stalls at the end with "Clearing geometry..." » can't cancel, have to restart Houdini.
4-Have the objects cached to abc, scattered » render with displacement » takes like 5 minutes to even start the render, then the buckets are stuck forever » can't cancel, have to restart Houdini.

I'm trying to see if Vray 7 is viable in Houdini, and most likely i'm doing something wrong, but i've spent all afternoon with this and can't make it work. Problem is that if i want to render in network i have to pre-cache the scatter objects to abc, so right now I can't even do it because it crashes with or without displacement.

There's nothing in the docs about how to work with instancing and displacement, so i'm kinda lost here. Some example files with instancing + disp working properly would be great for newcomers like me.

Houdini 20.5.410
Vray 7

[chakarov]

Hi mori4h , seems to work on my side. Can you share a simple scene ?

[mori4h]

Hi, sure, the attached hip is crashing as soon as you render.

Meanwhile i found out if i enable "Use Rayserver Mode" in the scatter object it renders ok, not sure why.

[bdancer]

> if i enable "Use Rayserver Mode" in the scatter object it renders ok, not sure why.

It's a mode of instancing when render primitives are "encapsulated" similar to packed pritmitives and this mode uses much less RAM.
It's not enabled by default because (by design) it's potentially slower if there are nested levels of "packs".
For the future updates there is plan to make this mode the default one (with an additional "depth" control).

[mori4h]

I see, thing is it's just 1 object being scattered 50 times or so and i'm not even running out of RAM, it simply just crashes left and right.
Rayserver mode on the other hand is extremely fast even with displacement on the object. Glad it will be made the default one. Was driving me crazy to be honest!