FIX: No information about extensive lock conflicts in the SSAS msmdsrv.log file

Applies to: Microsoft SQL Server 2012 Analysis Services

Symptoms


Microsoft SQL Server 2012 Analysis Services (SSAS 2012) may intermittently not respond to user query or new user connection during extensive lock conflicts, and this behavior results in an extensive blocking or a deadlock. Take a blocking scenario for example. If there is a transaction session that holds a commitshared lock that prevents the commitwrite lock of another transaction session from continuously committing the processing operation on the database, any new connections to the database may not be served in a timely manner until the blocking situation is resolved. If you run SQL Server Profiler before the extensive blocking occurs, you receive the following message in the profiler trace, and you can take proper action such as aborting or canceling the blocking transaction session:
Progress Report Begin 6 - Commit
Notification 24 - Transaction abort requested         Transaction errors: Aborting transaction on session <SPID>.
The information indicates that a lock conflict occurs, and it is useful in troubleshooting both the extensive lock conflicts and post mortem analysis. However, no corresponding information is recorded in the SSAS log file msmdsrv.log.

Resolution


After you apply this hotfix, the following information is logged in the msmdsrv.log file when the lock conflict occurs:
  • The SPID of the transaction to be aborted.
  • The blocking SPID.
  • The time stamp of the blocking event and the attempts to abort the blocking transaction.

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

Cumulative Update 2 for SQL Server 2012 SP2

Status


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