FIX: Unexpected blocking or deadlocks after you install deprecated Cumulative Update 6 for SQL Server 2014 SP1

Symptoms

Assume that you install the original released and now deprecated Cumulative Update 6 for SQL Server 2014 Service Pack 1 (SP1) (build number 12.0.4449.0, KB 3144524), and that you are running workload patterns that include parallel SELECT(…)WITH NOLOCK, under the default SQL Server lock-based isolation level or a higher level. In this situation, you may encounter queries that experience blocking or deadlocks. 

The patterns that are exposed to this blocking issue are as follows:
  • Executing a parallelized SELECT (…) INTO Table FROM SourceTable statement, and specifically using the NOLOCK hint, under the default SQL Server lock-based isolation level or higher. In this scenario, other queries that try to access SourceTable will be blocked.
  • While one transaction is holding an exclusive lock on an object (for example, an ongoing table update), another transaction is executing parallelized SELECT (…) FROM SourceTable by using the NOLOCK hint. In this scenario, the SELECT query that is trying to access SourceTable will be blocked.
To find the current version of SQL Server that you have installed, see How to determine the version, edition and update level of SQL Server and its components.

Resolution

This problem was first fixed in the following cumulative update for SQL Server:


About cumulative updates for SQL Server
About cumulative updates for SQL Server

Status

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

References

Learn about the terminology Microsoft uses to describe software updates.
Properties

Article ID: 3167394 - Last Review: May 31, 2016 - Revision: 1

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