Isn't that only true for micro-benchmarking, though? Tiny little programs that fit in cache? I was under the impression that HT could provide great gains with a tiny executable (the bit of code being used, anyway) but with larger chunks of code that didn't fit in cache it was mostly useless.<p>I certainly know that in my own testing running ruby servers on both i7 and i5 iMacs that I see nothing close to a 50% speedup. More like 5-10%, max.