Hi All,

Yesterday night we did production upgrade from SQL Server 2014 STD to SQL 2014 SP1 and started seeing slowness.

I see query taking more time, in some instances about 3 times more duration. Is there any know bug with SP1 that is causing the slowness in the system.

Is there any options to improve performance or Rollback SP1. I am running Active/Active Cluster on Windows 2012 R2 STD.

Any Help Appreciated. Thank You.

-Kranp.

• Edited by kranp 14 hours 54 minutes ago

Hello,

Please compare the performance of the queries with the new and the old cardinality estimator as explained on the following post.

http://blogs.msdn.com/b/psssql/archive/2015/06/16/identifying-sql-server-2014-new-cardinality-estimator-issues-and-service-pack-1-improvement.aspx   

You can then adjust compatibility level based on the results and use the trace flags for the exceptions.

Hope this helps.

Regards,

Alberto Morillo
SQLCoffee.com

• Edited by Alberto MorilloMVP, Moderator 11 hours 52 minutes ago
• Proposed as answer by Shanky_621MVP 2 hours 11 minutes ago

You need to apply SP1 but you must also enable trace flag 4199 in order to activate the fix.