Clarification on instancing

[WoutTgh]

Hey Mikel,

I downloaded your scene, first thing I did was create the instances directly on points, the grid setup brings Houdini to its knees apparently. So I just added one point, and then used three copy and transform nodes to create a box of points, then set the instance attribute in a point wrangle " s@instance="/obj/Piggy/" ".

I'm rendering on a single GTX 1080 ti. Houdini 18.0.499 + Octane 2020.1.2

210x210x210 = 09 261 000 instances : memory (used/free): 4001/4917 MB : it renders and Houdini freezes when I try to close the IPR.
230x230x230 = 12 167 000 instances : memory (used/free): 5076/3781 MB : it renders and Houdini did not freeze when I closed the IPR. ( ? )
235x235x235 = 12 977 875 instances : memory (used/free): 5376/3778 MB : it renders and Houdini freezes when I try to close the IPR.
240x240x240 = 13 824 000 instances : CUDA error 2 on device 0: out of memory
250x250x250 = 15 625 000 instances : freeze/crash on preprocessing

Preprocessing took quite some time of course. It seems like something's going on with the memory usage or with the memory usage information that is being displayed.

I was curious so I did some tests with rendering the points as sphere particles:

300x300x300 = 27 000 000 particles : memory (used/free): 2806/5797 MB : it renders, IPR closed fine.
400x400x400 = 64 000 000 particles : memory (used/free): 5058/2940 MB : it renders, IPR still closed, not very responsive ( 64 Million particles though !! )
450x450x450 = 91 125 000 particles : freeze/crash on preprocessing.

[miko3d]

Thanks for the test WoutTgh ,

So it seem instancing has Issues anything over the 10million is hanging Houdini.

Is this Houdini Plugin or Core related?

[davidyannick_1]

Thanks for the test WoutTgh ,

So it seem instancing has Issues anything over the 10million is hanging Houdini.

Is this Houdini Plugin or Core related?

I've also tested same issues with one 1080Ti - i7 8700k - 64Gb RAM

[juanjgon]

This problem sounds to me like an Octane limitation related to the amount of geometry/particles/instances that it can handle into a single object. In this case, if you can break the OBJ node into several OBJ nodes with less than 10M instances each one, the rendering could work fine.

Have you tried to export the complex scene to an .orbx file from the Octane ROP node to check if the same problem happens there?

Thanks,
-Juanjo

[miko3d]

This problem sounds to me like an Octane limitation related to the amount of geometry/particles/instances that it can handle into a single object. In this case, if you can break the OBJ node into several OBJ nodes with less than 10M instances each one, the rendering could work fine.

Have you tried to export the complex scene to an .orbx file from the Octane ROP node to check if the same problem happens there?

Thanks,
-Juanjo

Thanks Juanjo,

Unfortunately splitting the scatter into several objects nodes didnt help,I tested with 2 instance objs of 4.5 million each and 2 different Geo and Same problem: hangs at that 9-10million instances mark.
I also tried to export the ORBX from the ROP node , but crashes Houdini.

[rafg]

Searching around...100 million+ instancing possible as of Octane version 2021.1.1 ? Any successful examples?

Running 3090's and hitting limit around 16 million. Low poly count but high object count.