1.2 (TYPES OF PROCESSOR)

Question 1

What is an array/ vector processor?

Answer 1

A processor that allows the same instruction simultaneously on multiple data location
e.g. GPUs

Question 2

What is a SIMD processor?

Answer 2

Single Instruction multiple data (SIMD)
e.g. CPU

Question 3

What is a GPU and how are they used?

Answer 3

Specialist processors used for rendering graphics, particularly 3D
applies the same instruction to many data locations

Question 4

What is a co-processor?

Answer 4

Additional processors for a specific task
e.g. floating point calculator

Question 5

What is a scalar processor?

Answer 5

Von Neumann

Question 6

What is are multicore/parallel processors?

Answer 6

Uses independant processors to work on the same program
programs must be written specifically for parallel processors

Question 7

What are the pros of multicore/parallel processors?

Answer 7

Pros:
Speed: if a task can be split the execution time can be reduced
Improved performance: Simultaneous computation can take place on different data subsets (this would be used in machine learning, data mining and scientific computing)
Better resource utilisation: multi core/processors can be used more effectively
Problem solving: Large and complex problems that can be parallel processed, can be solve more easily
Real time applications: Real time applications such as graphic rendering are more feasible

Question 8

What are the cons of multicore/parallel processors?

Answer 8

Cons:
Max speed limit: Limit to max speed if a task cant be parallelised
Complex: programming: Harder to write code
Debugging difficulty: More difficult to debug due to precise timing of events
Communication between processors: Takes significant time and resources, potentially outweighing the benefits of parallel processing
Limited applicability: not all tasks can be run in parallel

Question 9

What instruction sets can a computer use?

Answer 9

CISC (complex instruction set computer)
RISC (Reduced instruction set computer)

Question 10

Details of a CISC

Answer 10

Complex Instruction Set Computer (CISC) consists of a larger instruction set which includes more complex instructions
Emphasis on hardware
As the instructions are more complex, they can take more than one clock cycle to execute:
Memory to memory (‘LOAD’, ‘STORE’) incorporated in instructions
Has more general purpose registers
Instructions take up less space in memory
Is usually used in laptops and desktop computers

Question 11

Details of RISC

Answer 11

Reduced Instruction Set Computer consists of a smaller instruction set with more simple instructions
Each instruction takes one clock cycle to execute which makes it more suitable for
pipelining
Compilers are more complicated so will generate more instructions
Has fewer addressing modes
more transistors therefore more power usage
Is usually used in smartphones and tablets