3. Performance evaluation Assume for a given program, 60% of the executed instructions are arithmetic, 20% are load/store, and 20% are branch. a. Given this instruction mix and the assumption that an arithmetic instruction requires 2 cycles, a load/store instruction takes 6 cycles, and a branch instruction takes 3 cycles, compute the average CPI. b. How many cycles, on average, an arithmetic instruction should require to achieve 20% improvement in the overall performance, assuming that load/store and branch instructions are not improved at all.

3. Performance evaluation Assume for a given program, 60% of the executed instructions are arithmetic, 20% are load/store, and 20% are branch. a. Given this instruction mix and the assumption that an arithmetic instruction requires 2 cycles, a load/store instruction takes 6 cycles, and a branch instruction takes 3 cycles, compute the average CPI. b. How many cycles, on average, an arithmetic instruction should require to achieve 20% improvement in the overall performance, assuming that load/store and branch instructions are not improved at all.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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5-Consider a computer running a program that requires 400 s, with 80 s spent executing FP instructions, 40 s executed L/S instructions, and 40 s spent execut- ing branch instructions. • By how much is the total time reduced if the time for FP operations is reduced by 5%? • By how much is the time for INT operations reduced if the total time is reduced by 5%? • Can the total time can be reduced by 10% by reducing only the time for branch instructions?
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For a given number of instructions, assume CPI is increased by 20%, and clock cycle time is decreased by 20%. How would the execution time change? Not enough information to determine the change. The execution time will stay the same. The execution time will be decreased. O The execution time will be increased.
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