6 reasons why SQL Server is causing high CPU usage

The first type:

Compile and recompile the execution plan.

The second type:

Sorting and aggregation.

The third type:

Table JOIN operation.

The fourth type:

max degree of parallelism.

The fifth type:

Max worker threads.

The sixth type:

Cost Threadhold parallelism//Each statement its complexity has a cost value as a measure, when the cost value is more than Threadhold parallelism when the SQL Server

You can use multithreading to improve the execution speed of your statements. Therefore, increasing the cost threadhold parallelism value can reduce the parallelism of SQL Server. This reduces the degree of parallelism in SQL Server.

6 reasons why SQL Server is causing high CPU usage