UGC NET CSE | June 2016 | Part 2 | Question: 48

Question

Pipelining improves performance by

• A. decreasing instruction latency
• B. eliminating data hazards
• C. exploiting instruction level parallelism
• D. decreasing the cache miss rate

Comments

recategorize the question in CO you have added it in programming.

Answer 1

Answer is  3

The basic instruction cycle is broken up into a series called a  pipeline. Rather than processing each instruction sequentially (finishing one instruction before starting the next), each instruction is split up into a sequence of steps so different steps can be executed in parallel and instructions can be processed concurrently

Answer 2

Answer c

Pipelining is an implementation technique where multiple instructions are overlapped in execution.

• The computer pipeline is divided in stages.
• Each stage completes a part of an instruction in parallel.
• The stages are connected one to the next to form a pipe - instructions enter at one end, progress through the stages, and exit at the other end.
• Pipelining does not decrease the time for individual instruction execution. Instead, it increases instruction throughput.
• The throughput of the instruction pipeline is determined by how often an instruction exits the pipeline.
• Because the pipe stages are hooked together, all the stages must be ready to proceed at the same time.
• We call the time required to move an instruction one step further in the pipeline a machine cycle .
• The length of the machine cycle is determined by the time required for the slowest pipe stage.
• The pipeline designer's goal is to balance the length of each pipeline stage

Answer 3

A. False. Pipeline never reduce individual instruction delay

B.False. Not deal with any Hazards

C.True. Pipeline increases the througput of program by providing instruction level parrallelism (The Stages of instruction are working parellely)

D. false. Irrelevant with Cache Hit/Miss