Play using the attached reproduction place file. Observe the microprofiler on any frame and find the updateInvalidatedFastClusters tag. For context, 300 regular parts are also created under the character to show the additive effect, but descendant MeshParts (including default character parts) add much worse overhead than regular parts.
Reproduction.rbxl (28.6 KB)
RTX 2080 S
When I update a sub-part in a character model, I expect updateInvalidatedFastClusters to not re-process all the character descendant parts on the next frame.
When I update a sub-part in a character model, updateInvalidatedFastClusters triggers on the next frame.
As this mostly concerns custom character visuals/accessories which change frequently, these visuals can be welded to the character but parented to somewhere else like Workspace. This does not trigger updateInvalidatedFastClusters.
I expect the workaround is unintuitive and confusing to most developers, as they parent character-related parts to the character and won’t understand what this microprofiler tag represents or associate its cause to updating character sub-parts.
Issue Area: Engine
Issue Type: Performance
Date First Experienced: 2021-06-01 00:06:00 (+01:00)
Date Last Experienced: 2021-08-29 00:08:00 (+01:00)