Computer Organization & Design

Problem 6 15 points. Assume for arithmetic, memory access, and branch instructions, a processor has CPIs of 1, 12, and 5, respectively. Also assume that on a single processor a program requires the execution of 2.56 billion arithmetic instructions, 1.28 billion memory access instructions, and 256 million branch instructions. Assume that each processor has a 2 GHz clock frequency. Assume that, as the program is parallelized to run over multiple cores, the number of arithmetic and memory instructions per processor is divided by 0.7 x p (where p is the number of processors and p >= 2), but the number of branch instructions per processor remains the same. Find the total execution time for this program on 1, 2, 4, and 8 processors, and show the relative speed-up of the 2, 4, and 8 processor result relative to the single processor result. If the CPI of the arithmetic instructions was doubled, what would the impact be on the execution time of the program on 1, 2, 4, or 8 processors? II. III To what should the CPI of memory instructions be reduced in order for a single processor to match the performance of four processors using the original CPI values