Slowdown at Render End with V-Ray Proxies

This page covers the possible causes for slowdowns after rendering a project with many V-Ray Proxies and the available solutions.

Problem

You might see a slowdown at the end of rendering a scene with lots of V-Ray Proxy objects, where it takes a long time to release the memory used by V-Ray.

The most common reason for this is using V-Ray Proxy files created with earlier versions of V-Ray, where the Optimize for Instancing option was not yet available.

Solution

To solve the problem, the V-Ray Proxy objects need to be updated with the Optimize for Instancing option. To do this, follow these steps:

1. Import the geometry from the V-Ray Proxy object using the Import as Mesh feature.

    

2. After the geometry is imported in the DCC application, export it again to a V-Ray Proxy file with Optimize for Instancing enabled as shown in the previous section.

Additional Information

A quick way to find out if the Optimize for Instancing option is enabled for a particular .vrmesh file is to use the PLY to .VRmesh converter tool with the -info argument:

ply2vrmesh.exe C:\path\to\file.vrmesh -info

Information for "C:\path\to\file.vrmesh"
Number of frames: 1
Number of voxels: 55
Reading voxels... done
Total number of triangles: 345,944
Preview triangles: 9973
Channels:
Vertices
Faces
Maya info channel (data is valid)
File bounding box: [-63.500, -54.242, -57.715] - [63.500, 97.080, 57.714]
Voxels bounding box: [-63.500, -54.242, -57.715] - [63.500, 97.080, 57.714]
Vertices bounding box: [-63.500, -54.242, -57.715] - [63.500, 97.080, 57.714]
UV sets: 0
Color sets: 0
Shader sets: 1 ('default')

If the Number of voxels is greater than 2, Optimize for Instancing is NOT enabled and it's possible that this V-Ray Proxy file is causing the slowdown at the render end.