Explanation/Reference:
Explanation:
To carry out multitasking, the operating system sometimes moves process threads among different processors. This is efficient from an operating system point of view, but can reduce SQL Server performance under heavy system loads, as each processor cache is repeatedly reloaded with data.
Assigning processors to specific threads can improve performance under these conditions by eliminating processor reloads; such an association between a thread and a processor is called processor affinity.
References:
https://msdn.microsoft.com/en-us/library/ms189629%28v=sql.110%29.aspx