4 consider two different implementations of the same

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4. Consider two different implementations of the same instruction set architecture. The instructions can be divided into four classes according to their CPI (classes A, B, C, and D). P1 with a clock rate of 2.5 GHz and CPIs of 1, 2, 3, and 3, and P2 with a clock rate of 3 GHz and CPIs of 2, 2, 2, and 2. a. [10] Given a program with a dynamic instruction count of 1.0E6 instructions divided into classes as follows: 10% class A, 20% class B, 50% class C, and 20% class D, Which is faster: P1 or P2?
P1 : CPU time =10 6 * (1/2.5*10 9 ) [1*10/100 + 2*20/100 + 3*50/100 + 3*20/100] = 10 6 * 2.6 * 1/2.5*10 9 = 1.04 * 10 -3 P2 : CPU time =10 6 * (1/3*10 9 ) [2*10/100 + 2*20/100 + 2*50/100 + 2*20/100] = 10 6 * 2 * 1/3*10 9 = 0.66 * 10 -3 P2 is faster b. [10] What is the global CPI for each implementation?
c. [10] Find the clock cycles required in both cases.

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