1.1.2 Types of Processor

Question 1

what is an instruction set?

Answer 1

instructions that a computer is able to carry out

Question 2

what are the characteristics of a CISC processor?

Answer 2

• larger instruction set with more complex instructions
• instructions take more than 1 clock cycle to execute
• more general purpose registers
• instructions take up less memory

Question 3

what are the characteristics of RISC?

Answer 3

• smaller instruction set with simpler instructions
• instructions take 1 clock cycle to execute (suitable for pipelining)
• has fewer addressing modes
• fewer registers

Question 4

what are the advantages of RISC?

Answer 4

• uses less power
• costs less to manufacture

Question 5

what are the advantages of CISC?

Answer 5

• takes up less space in memory

Question 6

what is a GPU?

Answer 6

graphics processing unit

Question 7

what is a co-processor?

Answer 7

any additional processor used for a specific task

Question 8

why are co-processors used?

Answer 8

to improve the overall speed of the comptuer by excecuting concurrently with the CPU

Question 9

what are GPUs good at?

Answer 9

performing simple instructions on large data sets

Question 10

what are CPUs good at?

Answer 10

performing complex instructions on small data sets

Question 11

what is the diffference between a CPU and a GPU?

Answer 11

• CPUs are more general purpose (run faster generally)
• GPUs are speciallised for performing instructions on large data sets eg. rendering graphics (faster for specific tasks)

Question 12

what is SIMD processing?

Answer 12

• simple instruction multiple data
• having multiple processing elements which perform the same operation on multiple data points simultaneously

Question 13

what else are GPUs used for?

Answer 13

• oil exploration
• weather modelling
• machine learning
• linear algebra
• statistical analysis
• stock option predictions
• gravitational field theory

Question 14

what is a multicore processor?

Answer 14

a single chip that has two or more independent processing units

Question 15

what are the benefits of multicore processing?

Answer 15

• multitasking - each core can process something different
• background tasks - multicore processor can assign background tasks to one core which reduces their impact of speed on the other tasks
• improved responsiveness - if a program becomes unresponsive, another core can continue to run the program to stop it slowing the computer down

Question 16

what is parallel processing?

Answer 16

the processing of program instructions by dividing them between multiple processors or processor cores

Question 17

what are the advantages of parallel processing?

Answer 17

• increase speed and performance
• problem solving - large problems can be solved more easily
• real time applications eg. graphics rendering are improved

Question 18

what are the disadvantages of parallel processing?

Answer 18

• limit on maximum speed - not all parts of a program can be parallelised
• complex programs - harder to write code for parallel processing as data has to be synced and shared correctly
• communication between processors takes time
• limited applicability - not all programs can use the parallel processing
• more difficult to debug because of the precise timing of events