Moved from: bobsql.com
SQL Server uses 3 types of affinity to control where the SQL Server worker threads execute. Before explaining the different scheduler affinity types let me clarify some terminology.
SQL Server makes a specific distinction between scheduling and memory nodes.
Scheduling nodes: sys.dm_os_nodes
Memory nodes: sys.dm_os_memory_nodes
A scheduling node is a used to group a set of SQLOS schedulers. The scheduling node must :
– Remain within a single memory node.
– Can be configured to use a subset of the CPUs presented by the OS from the