Ok my bad i wasn't clear
I know very well the differences between cpu types in performance.
My question is: when i'm compiling a kernel on a new Xeon server. what will it matter if i compile it picking the new Core2/Xeon processor family or the Pentium 4/ older xeon processor family ( all are 8586 compatible).
and to that matter Amd processor too, i already tried running a kernel compiled with the processor type option in the kernel config = P4.
and it worked fine on new Quad core servers, cat /proc/cpuinfo showed all the cores since another option in the kernel config was picked - support multiple cores.
Does this option in the kernel .config (processor family)has any effect? and if so, on what ?