For SQL Server parallelism settings, consider the following recommendations:
- Max Degree of Parallelism—This SQL Server configuration option controls the number of processor cores that are used for the parallel execution of a query. If the SQL Server VM migrates from hosts with different core configurations, leave this setting at 0 (all cores exposed to SQL Server); however, if that is not the case, use a different value. This value is tightly integrated with the workload and must be chosen carefully to avoid regressive parallelism.
- Cost Threshold for Parallelism—This SQL Server configuration option specifies a threshold at which query plans run in parallel. Change the value of this setting from its default value of 5 to 50. You can adjust this number further depending on the workload requirements.
For more information about parallelism settings, see MAXDOP of Confusion.