Quiz 1

Question 1

What are the three main purposes of an operating system?

Answer 1

1 Execute user programs and make solving user problems easier
2 Make the computer system convenient to use
3 Use the computer hardware in an efficient manner

Question 2

What is the 4 components of a Computer System’s Structure?

Answer 2

Hardware, Operating System, Application Programs, Users

Question 3

What are some Roles of the OS?

Answer 3

Referee-Allocates resources, Isolates users and apps, communicates between users and apps
Illusionist-Each app seems to have the entire machine to itself

Question 4

What are the main services that the OS provides?

Answer 4

Program execution, I/O operations, File Systems, Communication, Resource Allocation, Accounting, Error Detection, Protection and Security

Question 5

What are the different types of User Interfaces an OS would have to deal with?

Answer 5

GUI, Touch Screen, Command Line

Question 6

What does the Command Line Interpreter do?

Answer 6

Takes in direct key inputs from keyboard and displaces results in a terminal or shell.

Question 7

What does a GUI do?

Answer 7

Its a user friendly desktop interface. Modern computer types

Question 8

What are system calls?

Answer 8

Programming interfaces to the services provided by the OS.

Question 9

How are system calls typically implemented?

Answer 9

Through a table which has each call indexed by number.

Question 10

What are the 3 general methods to pass parameters to the OS?

Answer 10

1 Pass the parameters in registers.
2 Parameters stored in a block or table in memory, address of block passed as a parameter in a regiser
3 Parameters pushed onto the stack by the program and popped off by the OS

Question 11

What are the types of system calls?

Answer 11

Process Control, File Management, Device Management, Information Maintenance(Date and Time), Communications, Protection

Question 12

What are the services the system provides?

Answer 12

File manipulation, Status information, Programming language support, Program loading and execution, Communications, Background Services, Application Programs

Question 13

What is the purpose of System Services?

Answer 13

Provide a convenient environment for program development and execution.

Question 14

What is a shell?

Answer 14

A job control system
Allows the programmer to create and manage a set of programs to do some task.

Question 15

What are the User goals of an OS?

Answer 15

The OS should be convenient to use easy to learn, reliable, safe and fast

Question 16

What are the System goals of an OS?

Answer 16

Operating systems should be easy to design, implement and maintain as well as flexible, reliable, error-free and efficient

Question 17

How are OS implements in the modern day?

Answer 17

Lowest levels in assembly, main body in C, various systems programs in C, C++ PERL and Python

Question 18

Emulation allows for?

Answer 18

OS to run on non-native hardware.

Question 19

What are the various ways to structure an OS?

Answer 19

Monolithic-One big program
Microkernels-Very small kernel most processes done in user space
Modular-OS has loadable kernel modules

Question 20

What are the benifits and downsides of MicroKernels?

Answer 20

Benefits: Easy to extend, Easy to port, More reliable, More secure
Detriments: Performance overhead of user space to kernel space communication

Question 21

What are the benefits to Modules?

Answer 21

Benefit: Save memory, Faster to maintain and debug, Modules are loaded as fast as kernels

Question 22

What is the system structure of Linux?

Answer 22

Monolithic plus modular design

Question 23

What is a Process?

Answer 23

A program in execution.

Question 24

What are the parts of a process?

Answer 24

The program code ie text section, current activity, stack, data section, heap.

Question 25

What is contained in the stack?

Answer 25

Function parameters, return addresses, local variables.

Question 26

What is contained in the data section?

Answer 26

Global variables

Question 27

What is contained in the heap?

Answer 27

Memory dynamically allocated during run time.

Question 28

What does the virtualized processor do?

Answer 28

Give the process the illusion that it monopolizes the system.

Question 29

What does virtual memory do?

Answer 29

Lets the process allocate and manage memory as if it owned all the memory in the system.

Question 30

What are instructions?

Answer 30

The fundamental unit of work.

Question 31

What are the 5 states of a process?

Answer 31

New, Running, Waiting, Ready, and Terminated

Question 32

What does the Process Control Block hold?

Answer 32

Information associated with each process.

Question 33

What selects among available processes for the next execution on a GPU core?

Answer 33

The Process Scheduler

Question 34

What is a context switch?

Answer 34

What occurs when the CPU switches from one process to another.

Question 35

How are processes identified?

Answer 35

With their PID or process identifier

Question 36

What are the two models of Interprocess Communication?

Answer 36

Shared Memory and Message Passing

Question 37

What is shared memory communication?

Answer 37

When a single area of memory is shared among the processes that are communicating.

Question 38

What is the major issue to deal with with shared memory communication?

Answer 38

Synchronizing the user processes with each other.

Question 39

What is the paradigm for cooperating processes?

Answer 39

The Producer-Consumer Model

Question 40

What are the two variations of the Producer-Consumer Problem?

Answer 40

Unbounded-buffer and Bounded-Buffer

Question 41

What are pipes?

Answer 41

Conduits allowing for two processes to communicate

Question 42

What are the two pipes?

Answer 42

Ordinary Pipes, and Named Pipes (Not needed to be accessed with a Parent Child Relationship)

Question 43

What is a socket?

Answer 43

An endpoint for communication.

Question 44

What are stubs?

Answer 44

Client-side proxy for actual procedures on a server