Compute the overall (Cache) performance CPU:

A processor runs at 3.0 GHz and has a CPI=1.5 for a perfect cache (i.e. without including the stall cycles due to cache misses). Assume that load and store instructions are 25% of the instructions. The processor has an I-cache (Instruction cache) with a 5% miss rate and a Dcache (Data memory cache) with 4% miss rate. The hit time is 1 clock cycle for both caches.

Assume that the time required to transfer a block of data from the main memory to the cache, i.e. miss penalty, is 40 ns.

a. Compute the number of stall cycles per instruction

b. Compute the overall (cycle per instruction) CPI

c. Compute the average memory access time (AMAT) in ns.