Question

Performance of Compilers [25 pts.] In this question, we are given two different compilers with name Batman and Robin that are tested for 1 GHz. machine with 3 classes of instructions: Class Bane, Class Dent and Class Penguin that requires 1, 2 or 3 cycles respectively. We have a huge line of code and we will compare the performance of these compilers. Batman Robin Bane Instructions 10 million 20 million Dent Instructions 3 million 1 million Penguin Instructions 2 million 2.5 million According to MIPS software, which software will be faster? Please add the calculations to get credit. Specifically, how many CPU clock cycle is needed for these compilers to finish the code? How much time it takes to complete the code?

Answer 1

For Batman
Total clock = 10*1 + 3*2 + 2*3 = 22 millions
Total instruction = 15 millons
average clock per Instruction = (22*10^6)/(15*10^6) = 22/15
MIPS = 10^9/(22/15) = (15000/22)*10^6 = 681.81 MIPS
execution time = 22*10^6/(10^9) = 0.022 seconds

For Robin
Total clock = 20*1 + 1*2 + 2.5*3 = 29.5 millions
Total instruction = 23.5 millons
average clock per Instruction = (29.5*10^6)/(23.5*10^6) = 29.5/23.5
MIPS = 10^9/(29.5/23.5) = 796.61 MIPS
execution time = 29.5*10^6/(10^9) = 0.0295 seconds

According to MIPS , software Robin is faster (796.61 > 681.81)