Linked File worksets
For performance control it is recommended to place both the type and the instance(s) of a linked file on the same workset.
Reason: This will enable you to control if a Revit linked file is loaded at startup and therefore you have control over the load performance of Revit.
Type workset
With the type workset assignment you will be able to influence the load performance.
Instance workset
With the instance workset assignment you will be able to influence the view regeneration performance.