Cache Decay: Exploiting Generational Behavior to Reduce Cache Leakage Power

Q1. The Skier's Dilemma: A beginning skier does not know how many times
    he/she is going to ski in a lifetime. New skis cost $400 and ski
    rentals cost $20. The dilemma: when does the skier buy new skis? What
    is the ski-purchase heuristic that guarantees that the skier will never
    spend more than twice the optimal amount?

Q2. How well will the decay approach apply to other storage structures on
    the chip: (i) L2 (ii) branch predictor (iii) register file?