Cache:

Suppose we have a processor with a clock rate of 4 GHz and a base CPI that would be 2.0 iff all references hit in the primary cache. Assume a main memory access time of 50 ns, including all miss handling. Suppose the miss rate per instruction at the primary cache is 4%.

a) What is the miss penalty to main memory?

b) What is the effective CPI with one level of caching?

c) Now assume that we add a secondary cache that has a 2.5 ns access time for either a hit or miss and is large enough to reduce the miss rate to main memory to 1%. What is the miss penalty for an access to this second-level cache?

d) How much faster will the processor be after secondary cache has been added?