KB2895494 - Slow SQL Server performance and a memory leak after you apply Cumulative Update 3 for SQL Server 2012 Service Pack 1 or in SQL Server 2014

Symptoms

After you apply Cumulative Update 3 for Microsoft SQL Server 2012 Service Pack 1 to an instance of SQL Server or in SQL Server 2014, SQL Server performance might be slow, and a memory leak might occur.

If you run the following query when this problem occurs, you see that the Mem in MB value and the row count value keep increasing for the MEMOBJ_COMPILE_ADHOC memory object:

select type, sum(pages_in_bytes)/1024.0/1024.00 'Mem in MB', count (*) 'row count' from sys.dm_os_memory_objects
where type like '%MEMOBJ_COMPILE_ADHOC%'
group by type

Notes

• The DBCC FREEPROCCACHE command does not help reduce the Mem in MB value.

• This problem only occurs when you run many sp_prepare procedures to prepare parameterized Transact-SQL statements.

Resolution

The issue was first fixed in the following cumulative update of SQL Server.

Status

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

References

See the terminology that Microsoft uses to describe software updates.