Thinking About Parallelism

Grant Fritchey continues his thoughts on parallelism:

Microsoft set the default value for the Cost Threshold for Parallelism back in the 1990s. They were developing SQL Server 2000. That means this value was determined as a good starting point for query plan costs over 17 years ago. In case you’re not aware, technology, T-SQL, SQL Server, and all the databases and database objects within them shifted, just a little, in the intervening 17 years. We can argue whether or not this value made sense as a starting point (and remember, the default settings are meant to be starting points covering a majority of cases, not a final immutable value) for determining your Cost Threshold for Parallelism 17 years ago. I think we can agree that it’s no longer even a good starting point.

For more thoughts, check out a prior post on figuring out the cost threshold.

Related Posts

Managing Central Management Server

Chrissy LeMaire shows how you can use dbatools to manage Central Management Server and registered servers: It’s a super useful feature that not all DBAs know about. Since CMS data is stored in msdb and accessible via SMO, you can access it from SQL Server Management Studio or PowerShell modules like dbatools. Central Management Server’s essential […]

Read More

Checking File Sizes In SQL Server

Andy Mallon looks back at a contribution by Junior DBA Andy, this one on checking file sizes: This is every DBA’s favorite game. Figuring out what DMV contains the data you want. It turns out there are two places that database file size info is maintained. Each database has sys.database_files which has information for that database. The […]

Read More

Categories

March 2017
MTWTFSS
« Feb Apr »
 12345
6789101112
13141516171819
20212223242526
2728293031