ID 472129 - Long waiting times when a new Object version, with additional UDIM Patches, is imported into a project containing MCBP nodes

Problem summary
Long waiting times when a new Object version, with additional UDIM Patches, is imported into a project containing MCBP nodes 

Customer reported version
Mari 4.7v1

Customer reported platform
Linux

Steps to reproduce

1) Download the attached geometry files (Or use one mesh with one UDIM Patch and one mesh with multiple UDIM Patches)

2) Create a project using the mesh which has one UDIM Patch

3) Create 8 Multi-Channel Bake Point nodes

4) In the Objects Palette, import the geometry with additional Patches as a new Object version.

Expected behaviour
The new Object version should take a reasonable amount of time to import.

Actual behaviour
The new Object version is imported, but it takes far longer than it would in a project without any MCBP nodes.

The import time is longer if the MCBP nodes are configured for a Shader model that has a high number of inputs.

Workaround

1) Delete any Multi-Channel Bake Point nodes

2) Save the project and close it, then reopen it

3) Import the new Object version

4) Recreate the Multi-Channel Bake Point nodes

Reproduced by support
This bug has been reproduced in:

Mari 4.7v2 - Windows 10 - CentOS 7.7

Mari 4.7v1 - Windows 10 - CentOS 7.7

Earliest version tested
Mari 4.7v1 - This feature did not exist before this version