Fundamentals of Information Technology

1). How does an operating system ensure that hardware is used efficiently? Operating system can ensure processor to be used efficiently by the multiprogramming feature. Since the processor is fast while I/Os are slow, operating system needs to prevent processor from wasting time doing nothing and just waiting for I/O to complete. By having more than one program in memory, operating system will be able to let processor work on another program while the first program is waiting for I/O to complete. Once the first program’s I/O is done, operating system will let processor to resume the first program. In this way, processor can be kept busy working on different programs while certain I/Os are taking …show more content…

There’s a pipeline of different instructions. The instruction cycle is separated into several parts/stages. When the first part of the Instruction A is done, the processor can execute the first part of the Instruction B while still continue to execute the second part of the Instruction A. Different stages of different instructions will overlap. The process is actually working on several instructions at same time which will increase the number of instructions being executed at the same time. Therefore the process’s performance is increased.
Another technology to increase system performance is called “Hyper-Threading” technology. It allows one physical process to perform as two or more virtual processors so that they can execute two or more instructions at the same time. The multi-core technology is widely used in our personal computers today.
The third technology is to improve the speed and width of buses. Buses are responsible for transferring data and control. With higher speed and larger bus width number, the system can perform faster or better.

5). The speed of a computer system isn’t based solely on the speed of the processor. Discuss how cache memory and newer busses have contributed to faster computer systems over the years.
Here’s how cache memory contribute to faster computer system. Processor needs to fetch data and instructions from main memory. However, main memory works much slower than