Hi,
this warning is part of a feature that was introduced with 5.5 to handle non-nanite job marking queue overflow more gracefully (with this commit) and may appear in projects after upgrading to 5.5. As mentioned in the topic you linked, Virtual Shadow Maps are best used in conjunction with Nanite as they rely on Nanite’s efficient culling and drawing. The recommended approach is to convert non-Nanite meshes to Nanite to make better use of VSM. You may also consider switching the shadow method to Cascaded Shadow Maps if non-Nanite meshes are required, but this will likely impact performance to some degree.
To find out which meshes are non-Nanite, you can use the “Nanite Visualization” mode (under “Lit” in the 3D viewport) and select “Mask”. This will show all Nanite meshes as green and non-Nanite as red. This visualisation mode will only work when there is at least one Nanite mesh in the scene.
I hope this is useful. Please let me know if you need more help.
Thanks,
Sam