March 2009 - Posts

Should you worry about SOS_SCHEDULER_YIELD?
18 March 09 02:05 AM | josephsa | 1 Comments   

Today I witnessed a performance load test against a 16 proc 64-bit SQL Server instance. During the first run we saw a very high value for CXPACKET, followed up with SOS_SCHEDULER_YIELD. After disabling parallelism and clearing the wait stats, CXPACKET Read More...

SQL Server 2008 Query Performance Tuning Distilled
14 March 09 03:09 AM | josephsa | 1 Comments   

Today I received a copy of SQL Server 2008 Query Performance Tuning Distilled by Grant Fritchey (aka ScaryDBA ). I was the technical reviewer for this book and I really enjoyed the project. SQL Server performance is one of my favorite topics, and Grant Read More...

SQL Server 2008 Transact-SQL Recipes - Source Code
09 March 09 11:07 PM | josephsa | 1 Comments   

I recently heard from a reader of SQL Server 2008 Transact-SQL Recipes who was looking for the downloadable Transact-SQL source code from the book. Turns out he was using my book in a class he was teaching. Although Transact-SQL Recipes is not really Read More...

Identifying Hypothetical Indexes
05 March 09 08:24 PM | josephsa | 1 Comments   

If you have ever interupted Database Tuning Advisor prior to a full completion of a workload evaluation, you may notice that your tables have indexes with naming conventions like "_dta_index_tablename_NNN". You can see these hypothetical indexes in sys.indexes Read More...