CS 61C (Fall 2007)

Quiz 38

Four questions, submit as "quiz38". Due 2:45pm before lecture 12/3/2007.

We wish to compare the performance of two different computers C1 and C2. The following measurements have been made:

Program	Time on C1	Time on C2
P1	2.0s	1.5s
P2	5.0s	10.0s

Which computer is faster for P1?

Which computer is faster for P2?

Suppose you want to run a program P with 7.5*10⁹ instructions on a 5GHz mcahine with a CPI of 0.8.

What is the expected CPU time (answer in seconds)?

When you run P, it takes 3 seconds of wall clock time to complete. What is the percentage of CPU time that P received?