Assume that you manage model object permissions on the Manage Groups page in SQL Server 2017 Master Data Services (MDS) and Microsoft SQL Server 2016 MDS. When you expand the Entities folder of a model, you may notice that it takes a long time to display all the entities under the folder. Additionally, the more entities it has, the longer time that it might take.
This issue is fixed in the following cumulative updates for SQL Server:
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Learn about the terminologythat Microsoft uses to describe software updates.