JNU PhD CS 2019
October 3, 2023JNU PhD CS 2019
October 3, 2023JNU PhD CS 2019
| Question 6 |
| require different amount of time | |
| require about the same amount of time | |
| require different amount of time with time difference between any two tasks being same | |
| require different amount with time difference between any two tasks being different |
Consider 4 stages in pipeline P1, P2, P3, P4, with each stage requires 1ns.
For large no. of instructions the time taken by pipeline to execute one task is 1ns.
But for non pipeline the time taken to execute one task is,
Case 2:
Now let’s consider 4 stages pipeline P1, P2, P3, P4, with each stage requiring 1ns, 2ns, 3ns, 4ns.
For large no. of instruction the time taken by pipeline to execute one task is
max(1, 2, 3, 4)ns = 4ns
But for non pipeline the time taken to execute one task is,
1 + 2 + 3 + 4 = 10ns
Hence from above it can be clearly seen that the concept of pipelining is most effective in improving performance if the tasks being performed in different stages require about the same amount of time.
Consider 4 stages in pipeline P1, P2, P3, P4, with each stage requires 1ns.
For large no. of instructions the time taken by pipeline to execute one task is 1ns.
But for non pipeline the time taken to execute one task is,
Case 2:
Now let’s consider 4 stages pipeline P1, P2, P3, P4, with each stage requiring 1ns, 2ns, 3ns, 4ns.
For large no. of instruction the time taken by pipeline to execute one task is
max(1, 2, 3, 4)ns = 4ns
But for non pipeline the time taken to execute one task is,
1 + 2 + 3 + 4 = 10ns
Hence from above it can be clearly seen that the concept of pipelining is most effective in improving performance if the tasks being performed in different stages require about the same amount of time.