Week 1

Question 1

What are the four components of a computer system?

Answer 1

1. Hardware - provides basic computing resources (CPU, memory , I/O devices)
2. Operating System - Controls and coordinates use of hardware among various applications and users
3. Application Programs - define the ways in which the system resources are used to solve the computing problems of the users (e.g. word processors, compilers, web browsers)
4. User - People, machines, other computers

Question 2

What are the two viewpoints in relation to operating systems?

Answer 2

1. User view - maximise the work that the user is performing. The OS is designed for ease of use and good performance
2. System view - OS acts as a resource allocator. A computer system has many resources such as CPU time, memory space, storage space, Input and output devices and so on. The OS acts as the manager of these resources.

Question 3

What is a kernel?

Answer 3

A kernel is the one program that is running at all times on the computer. The kernel is interrupt driven

Question 4

What does a bus do in a computer system?

Answer 4

The bus provides access to shared memory for CPUs and device controllers (e.g. disk controller, USB controller, graphics adapter)

Question 5

What is an interrupt?

Answer 5

An interrupt is a signal emitted by hardware when a process or an event needs immediate attention. Interrupts are used to interact between OSs and hardware.

Question 6

What are interrupt priorities used for?

Answer 6

Interrupt priorities are used by operating systems to identify the most urgent work to be done.

Question 7

Why is interrupt handling important?

Answer 7

Interrupt handling is important as efficient interrupt handling is required for good system performance.

Question 8

What is main memory?

Answer 8

The main memory is the only large storage media that the CPU can access directly

Question 9

What is secondary storage?

Answer 9

Secondary storage is an extension of main memory that provides large non-volatile storage capacity.

Question 10

What is volatile storage?

Answer 10

Volatile storage is storage that loses its content when power is turned off or otherwise lost.

Question 11

What is non-volatile storage?

Answer 11

Non-volatile storage is storage that keeps its contents even when power is turned off.

Question 12

What are HDDs?

Answer 12

Hard Disk Drives (HDD) are a form of non-volatile storage that contain a rigid metal or glass platter covered with magnetic recording material.

Question 13

What is the storage hierarchy?

Answer 13

The storage hierarchy is a model which orders the different types of storage from fastest to slowest access time. It is divided into volatile and non-volatile storage and there are 7 different types of storage listed in the heirachy.

Question 14

What are the three types of storage in the storage structure?

Answer 14

1. The CPU
2. Main Memory
3. Secondary Storage

Question 15

What are registers?

Answer 15

Registers are a volatile type of storage that hold a piece of information such as computer instructions or storage addresses.

Question 16

What are caches?

Answer 16

Caches are a type of volatile storage that stores all the frequently used data and instructions of a device.

Question 17

What is a single processor system?

Answer 17

A system that contains a single processor containing one CPU with a single processing core.

Question 18

What is a CPU?

Answer 18

A CPU is the hardware that executes instructions. It can load instructions only from memory, so any programs must first be loaded into memory to run.

Question 19

What is a processor?

Answer 19

A processor is a physical chip that contains one or more CPUs

Question 20

What is a core?

Answer 20

A core is the component that executes instructions and registers for storing data locally.

Question 21

What are clustered systems?

Answer 21

Clustered systems are multiple systems working together sharing storage via a storage-area network.

Question 22

What is a bootstrap program?

Answer 22

A bootstrap program is a program with simple code that initialises the system and loads the kernel.

Question 23

What does multiprogramming do?

Answer 23

Multiprogramming organizes jobs (code and data) so the CPU always has one to execute. A subset of total jobs in system is kept in memory. One job is selected and run via job scheduling.

Question 24

What is timesharing?

Answer 24

Timesharing (multitasking) is logical extension in which CPU switches jobs so frequently that users can interact with each job while it is running, creating interactive computing.