In SQL Server 2012, you may notice that high CMEMTHREAD waits on memory object MEMOBJ_SESCHEMAMGR.
This issue is fixed in Cumulative Update 5 for SQL Server 2012 Service Pack 3.
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:
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Learn about the terminology that Microsoft uses to describe software updates.