Chapter 1, Problem 1.14.1E

Given,

The number of Floating Point (FP) instructions is 50 × 106

The number of INT instructions is 110 × 106

The number of L/S instructions is 80 × 106

The number of branch instructions is 16 × 106

The Cycle Per Instructions (CPI) of FP, INT, L/S and branch instructions is 1, 1, 4 and 2 respectively.

The number of clock cycles can be calculated using the following formula is given below:

Clock cycles = CPIfp × Number of FP instructions+ CPIint × Number of INT instructions+ CPIl/s × Number of L/S instructions+ CPIbranch × Number of branch instructions

Substitute, “1” for “CPI_fp”, “50 × 106” for “number of FP instructions”, “1” for “CPI_int”,”110 × 106” for “number of INT instructions”, “4” for “CPI_l/s” “80 × 106” for “number of L/S instructions”, “2” for “CPI_branch” and “16 × 106” for “number of branch instructions” is given below:

Clock cycles = (1 × 50 × 106) + (1 × 110 × 106) + (4 × 80 × 106) + (2 × 16 × 106)= 512 × 106

Therefore, the number of clock cycles is 512 × 106.

The time taken to execute the clock cycles can be calculated using the following formula is given below:

TCPU = Clock cyclesClock rate

Substitute, “512 × 106” for “clock cycles” and “2 × 109” for “clock rate” is given below:

TCPU = 512 × 1062 × 109= 0.256 seconds

The time required to execute the clock cycles is 0