A processor has a 3-level cache hierarchy. The L1 cache has a hit rate of 80%, L2 cache has a hit rate of 70%, and L3 cache has a hit rate of 60%. What is the overall hit rate?
Q1. A processor has a 3-level cache hierarchy. The L1 cache has a hit rate of 80%, L2 cache has a hit rate of 70%, and L3 cache has a hit rate of 60%. What is the overall hit rate?
Answer: 0.976
Explanation: Overall hit rate = L1 hit rate + (1 - L1 hit rate) * L2 hit rate + (1 - L1 hit rate) * (1 - L2 hit rate) * L3 hit rate = 0.8 + (0.2 * 0.7) + (0.2 * 0.3 * 0.6) = 0.976.