Assume that you use Microsoft SQL Server. When you run a query in which a parallel batch-mode sort operator exists, and at least one of the sort columns is of type 'nvarchar', you may encounter a non-yielding scheduler condition.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
This issue is fixed in the following cumulative updates for SQL Server:
About cumulative updates for SQL Server:
Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server: