Pipelining

Question 1

How does pipelining work

Answer 1

Fetch instruction 1
Fetch instruction 2 while decoding instruction 1
Fetch instruction 3 while decoding instruction 2 and executing instruction 1
Fetch instruction 4 while decoding instruction 3 and executing instruction 2
The will repeat with all instructions

Question 2

Why use pipelining

Answer 2

Without pipelining the various steps in the FDE cycle have to take place one after the other
By using pipelining the next instruction can be fetched while the processor is performing arithmetic and logic operations in the ALU

Question 3

How can pipelining be efficient

Answer 3

Can make efficient use of the various registers and on board CPU cache and it allows different parts of instructions across multiple stages to be held in different registers at the same time

Question 4

Instruction pipelining

Answer 4

Various stages an instruction must move through the processor

Question 5

Arithmetic pipeline

Answer 5

Consists of parts of arithmetic operation that can be broken down and overlapped as they are carried out

Question 6

Flush the pipe

Answer 6

Removing unnecessary instructions