# MCS-284 Chapter 1 Homework

When turning in a homework problem, mark it with the exercise number shown in bold here. These will be the reference numbers I use in reporting back your standing on the homework.

• 1.2b: Do exercise 1.2 on pages 58-59 using the data values labeled b. In parts 1.2.3-1.2.6, give each answer in units that make the corresponding numeric value be at least 1 and less than 1000. One byte equals 8 bits. The units of network throughput indicated as Mbit (megabit) or Gbit (gigabit) are actually Mbit/s or Gbit/s (megabit per second or gigabit per second).

• 1.4.1-3b: Do parts 1.4.1-1.4.3 of exercise 1.4 on page 60 using the data values labeled b. The two implementations mentioned in the problem are P1 and P2.

• 1.4.4-6b: Do parts 1.4.4-1.4.6 of exercise 1.4 on page 61 using the data values labeled b. The "speedup" means the number of times faster. These parts of the exercise are based on the table at the top of page 61.

• 1.x1: You are considering a change in the design of a computer. The software that runs on the computer is fixed, and will not be changed. The computer can execute floating point instructions in 4 cycles each and other instructions in 1 cycle each. The average CPI (for the particular software, which is fixed) is 2. A proposed revision to the computer's design would allow the cycle time to be reduced by 40%. However, the floating point instructions will now take 5 cycles and the other instructions will take 2 cycles.

1. What fraction of the instructions executed are floating point?

2. What is the average CPI of the new computer running the same workload?

3. Is the proposed change beneficial for this workload? Why or why not?

Instructor: Max Hailperin