System Architecture

System architecture

• Speed
• The processor is the brains of the computer because it processes data and carries out instructions
• All processors have a clock speed measured in hertz
• Typical speeds have spanned across MHz and GHz for example 1GHz processor executes about 1 billion instructions per second and 2GHz would process about 2 billion instructions per second.
• Cores
• Every processor has a core in which instructions are executed. Most processors have a multi-core a dual core or sometimes a quad core some can even go up to 8 cores.
• Each core executes instructions independently.
• A dual core may execute up to twice as many instructions as a single core

Slide 2

• Cache size
• All processors have a cache
• This is a very fast, and usually a very small amount of memory
• The cache holds commonly used instructions.
• What affects performance?
• Clock speed:
• Doubling the clock speed will double the number of instructions executed per second
• Cores:
• Quadrupling the number of cores may quadruple the number of instructions executed per second
• Cache size:
• Increasing the cache size will reduce the number of memory to disk transfers and thus may speed up processing of these instructions

Slide 3

• Embedded Systems
• A computer system that is made up of both hardware and software
• Often known as firmware
• Usually for very special tasks
• Don't usually contain an Operating system
• An example of an embedded system is a dishwasher