I can't think of a single valid reason why a program would wantSometimes you need extremely low overhead time measurements, which need not be too accurate. One way to do this is to dump rdtsc measurements into some array, and later scale it using the cpu frequency.
to know the MHz rating of a CPU. Given that it's a) approximate,
b) subject to change due to power management, c) completely nonsensical
across CPU vendors, and d) only one of many variables regarding CPU
performance, any program that bases any decision on the values found
by parsing that field of /proc/cpuinfo is utterly broken beyond belief.