system architecture

Question 1

a type of system architecture

Answer 1

von neumann architecture

Question 2

what is von neumann architecture

Answer 2

model that defines the behaviour of many modern computers

Question 3

cpu

Answer 3

central processing unit
executes program instructions,
performing calculations and comparisons
coordinating the behaviour of hardware
has several components

Question 4

components of cpu

Answer 4

arithmetic logic unit
control unit
buses
registers
clock

Question 5

alu

Answer 5

arithmetic logic unit
performs various operations
arithmetic operations
relational operations
logic operations

Question 6

cu

Answer 6

control unit
manages execution of instructions by coordinating the activities of the other hardware

Question 7

buses

Answer 7

collections of wires that transmit that transmit data between computer components
examples: address, data, control

Question 8

examples of buses and its function

Answer 8

data- moves data back and forth between the cpu snd memory

address- transmit memory locations. any data retrieved from or placed into memory belongs in a specific address or memory location

control- transmit commands ti other components

Question 9

registers

Answer 9

short term storage for small, specific pieces of data, within the cpu itself
one register would store data just received from memory, another would store the memory location from which that data came from

Question 10

clock

Answer 10

every action performed by the cpu must begin during a clock pulse.
a clock generates a pulse of billions of times each seconds (in modern pcs), synchronising the activities within the cpu

Question 11

Main memory

Answer 11

The main working area for data currently being used and programs currently running

Question 12

Types of main memory

Answer 12

RAM (random access memory)
ROM (read only memory)
Cache memory

Question 13

RAM

Answer 13

Random access memory
When a program is loaded from a computer’s hard disk, its data and instructions are loaded into RAM
Smaller and faster than hard disk
Volatile, it will content if it is turned off
More ram = more applications running at same time

Question 14

ROM

Answer 14

Read only memory
Cannot be edited or deleted, non volatile. Does not need go update data and instructions, typically store bootstrapping instructions (inst that tell computer initial steps in finding and initialising the OS when computer is turned on)

Question 15

Cache memory

Answer 15

Stores copies of data or instructions from RAM that are accessed regularly
Data can be accessed very quickly
It is usually very small, measured in kilobytes or megabytes

Question 16

Cpu performance

Answer 16

Higher performance = quicker execution of instructions
Factors affecting cpu perforance:
- number of cores
- clock speed
- size of cache
- type of cache

Question 17

Core

Answer 17

A single unit
Has an ALU and CU which execute instructions
Two cores can execute instructions at the same time
More cores = more instructions per second that can be executed

Question 18

Dual core

Answer 18

Two cores
Not exactly twice as fast as single core due to time lost for organising which core will follow which instruction (time called overhead)
Overhead is usually small enough so that dual can be considered twice as fast

Question 19

Quad core

Answer 19

Four cores
Around 4 times faster than single core

Question 20

Clock speed

Answer 20

Number of clock pulses per second
Typically measured in gigahertz
3GHz = 3 billion pulses per second

Question 21

Cache size

Answer 21

Used to store data that will be accessed repeatedly
More cache memory = larger amount of data can be stored
Since cache memory is faster than any form of memory, this would improve cpu performance

Question 22

Cache type

Answer 22

Can be L1 (level 1), L2 or L3.
L1 is the smallest in terms of capacity but the quickest, directly found in CPU
L2 is slighter bigger but slower and out of CPU
L3 is larger but more slower and further from CPU

Question 23

CPU can be enhanced by

Answer 23

Increasing number of corer
Increasing clock speed
Increase size of cache memory
Maximising use of L1 cache