Memory Hierarchy UGC

Question 1

Consider a system with 2 level cache. Access times of Level 1, Level 2 cache and main memory are 0.5 ns, 5 ns and 100 ns respectively. The hit rates of Level1 and Level2 caches are 0.7 and 0.8 respectively. What is the average access time of the system ignoring the search time within cache ?

• 20.75 ns
• 7.55 ns
• 24.35 ns
• 35.20 ns