While I am aware Mac OS X supports Hyperthreading, looking at the Activity Monitor tells a different story. I see 8 of my threads, but only 4 are used usually. In Windows, all 8 are used!

If I disable certain cores using CPUPallete, It will start using both threads per core on the non-disabled cores.

I am mostly curious as I am not experiencing any slow downs at all, I just want to know why.