Referring back to my post on hyperthreading, I had to remove quite a few procs to get the correct number of physical processors and logical processors for a customer test.
Unfortunately, I have found that using a "numprocs" boot.ini switch doesn't suffice for testing the correct number.
For example, we have a customer that would like to test on a couple of our 4-way servers (because it is what they have in production). However, they wanted two physical, hyperthreaded processors. If I left all four physical processors in the box, and rebooted using a numprocs=2 boot.ini switch, only two processors would show up (two physical, not hyperthreaded). Therefore, I had to physically remove 2 of the four processors in order to get the combination they wanted.
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