Hi all,

Learning Houdini and testing if it fits my needs, I imported a 3D scan as point cloud and plugged it in a “vdbfromparticles” node. With chosen voxelsize, I get 14 000 000 voxels. If I middle click on the vdb node, it says it requires 118MB Memory and it looks good. Computed in 2s, OpenVDB is really good !
Now the problem is, despite the 118MB mentioned, the windows task manager says Houdini takes 3GB of memory (250MB before voxelising). I saved and reloaded, same amount of memory is used
Am I doing something wrong? Looking at the example files on the OpenVDB website, which are from 3D scans too, I know OpenVDB can really be that efficient that it require only 100MB for 10Millions of 3D points. In the end, it was just a test and the final scan is much bigger, so I really need it to be memory efficient.
If someone knows a good way to visualize 3D scans in Houdini, I'll be happy

Note: In the end, it will be rendered in a pathtracer like Arnold. I tried the mesh way too, it just won't fit in 64GB and I don't have more.

Which version of Houdini are you using?

On Windows, this is likely a case of us using TBB Malloc and it tends to fragment the memory space very much. So in theory, the unaccounted memory that you see in the Task Manager is held up in thread-specific memory pools. If you then do other stuff that allocates memory from these threads (ie. anything VDB related), then that memory should in theory be reclaimable even though it's not release for other processes to use.

Another thing to try is to copy the tbbmalloc*.dll from Houdini 12.5 and overwrite the one in a vc11 install of Houdini 13.0 to forcibly disable use of TBB Malloc. However, this will cause Houdini will run slower as a result.

When you convert VDB to polygons, make sure you convert to PolySoup to take up less memory.

It seems if you switch to OGL 2.1 and load a scene that was created while H13 was set to OGL3.3 that scene won't load and cause a segmentation fault, crashing houdini. I didn't investigate this thoroughly, it may be that only softshadows or IBL or something causes this error.