Operating Systems

Question 1

Whats a operating system

Answer 1

Program that acts as an interface between the computer user and computer hardware, and controls the execution of programs

Question 2

WHat 3 parts does the OS manage

Answer 2

Memory
Processing
Hardware/Software on computer

Question 3

What are some responsibility of OS

Answer 3

file management, memory management, I/O handling, and peripheral device management

Question 4

What is process management

Answer 4

The OS handles one process at a time but is so fast it may seem like its concurrent

Question 5

Virtual memory serves 3 purposes…what are they

Answer 5

assure that each process has a unique address space

provide memory protection to prevent processes from using memory addresses

allow an application to use more memory than what is physically available

Question 6

Purpose of I/O management

Answer 6

Allows us to easily add additional hardware and configure it

Question 7

Whats the purpose of the secondary storage

Answer 7

For program to run data and its accesses the data must be in primary memory. The secondary is used to back up the main memory

Question 8

What is process management

Answer 8

Involves various tasks like creation, scheduling, termination of processes, and a dead lock.

Question 9

What must the OS do for process management

Answer 9

it must allocate resources that enable processes to share and exchange info. Also protects it from other methods that allow sync among processes

Question 10

What are the 4 architecture blocks of Process

Answer 10

Stack
Heap
Data
Text

Question 11

What is stack?

Answer 11

stores temporary data like function parameters, return addresses, and local variables

Question 12

Heap

Answer 12

allocates memory, which may be processed during run time

Question 13

data

Answer 13

contains a varaible

Question 14

text

Answer 14

includes current activity

Question 15

What is the PCB and what does it do

Answer 15

Process Control Block

• Data structure that is maintained by the OS for every process
• Helps you store all the info required to keep track of all running process
• store contents of processor registers

Question 16

Whats a process state

Answer 16

COndition of the process at a specific instant of time (defines current position of the process)

Question 17

List the 7 stages of a process

Answer 17

New -> Ready -> Waiting -> Executing -> Terminated

Executing -> blocked
executing -> suspended

Question 18

Stage: New

Answer 18

The new process is created when a program calls from secondary memory to primary memory

Question 19

Ready

Answer 19

Process should be loaded into the primary memory, which is ready for execution

Question 20

Waiting

Answer 20

Process is waiting for the allocation of CPU time and other resources for execution

Question 21

Executing

Answer 21

The process is an execution state

Question 22

Blocked

Answer 22

Time interval when a process is waiting for an event like I/O operation to complete

Question 23

Suspended

Answer 23

Tiem when a process is ready for execution but has not been placed in the ready queue by OS

Question 24

Terminated

Answer 24

Time process is terminated

Question 25

Important components of PCB

Answer 25

``` Process state program counter cpu registers cpu scheduling info accounting/business info memory-management info i/o status info ```

Question 26

process state

Answer 26

Process can be new, ready, running, waiting, etc

Question 27

Program counter

Answer 27

Lets you know the address of the next instruction, which should be executed for that process

Question 28

CPU registers

Answer 28

component includes accumulators, index, and General-purpose registers and info of condition code

Question 29

CPU Scheduling info

Answer 29

Includes a process priority, pointers for scheduling queues, and various other scheduling parameters

Question 30

Accounting/business info

Answer 30

includes the amount of CPU and time utilities like real time used, job or process numbers