Correct Affinity Mask and Affinity I/O Mask Overlap
This rule checks whether the instance of SQL Server has one or more processors that are assigned to be used with both the affinity mask and the affinity I/O mask options. On a computer that has more than one processor, the affinity mask and the affinity I/O mask options are used to designate which CPUs are used by SQL Server. Enabling a CPU with both the affinity mask and the affinity I/O mask can slow performance by forcing the processor to be overused.
Best Practices Recommendations
When you specify either the affinity mask or the affinity I/O mask options, you should specify both, but only enable each CPU no more than once.
Do not enable the same CPU in both the affinity mask option and the affinity I/O mask option. The bits that correspond to each CPU should be in one of the following states:
0 in both the affinity mask option and the affinity I/O mask option
0 in the affinity mask option and 1 in the affinity I/O mask option
1 in the affinity mask option and 0 in the affinity I/O mask option
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