Links and good reading
- This article by Bob Dorr explains how maxdop relates to worker threads.
- I wrote a post a while back on BrentOzar.com called, “How many CPUs is my parallel query using in SQL Server?” It shows how while you have multiple threads, your query still must follow the laws of maxdop. Bonus points: read the comments for extra nerdy fun.
- Microsoft documentation on Cost Threshold for Parallelism
- Microsoft documentation on Checking Objects in Parallel
- Paul White’s article on Forcing a Parallel Query Execution Plan has a helpful list of things that can require serial execution plans, or serial zones within execution plans