Introduction

Question 1

A program that acts as an intermediary between a user of a computer and the computer hardware.

Answer 1

Operating System

Question 2

The software responsible for the management and coordination of activities and the sharing of the resources of the computer.

Answer 2

Operating System

Question 3

Use the computer hardware in an efficient manner.

Answer 3

Operating System

Question 4

Its job is to coordinate the execution of all other software, mainly user applications.

Answer 4

Operating System

Question 5

Execute user programs and make solving user problems easier.

Make the computer system convenient to use

Use the computer hardware in an efficient manner

Answer 5

Operating system goals

Question 6

what are the steps of operating system?

Answer 6

User - application - operating system - hardware

Question 7

provides basic computing resources
cpu, memory, I/O devices

Answer 7

Hardware

Question 8

Controls and coordinates use of hardware among various applications and users

Answer 8

Operating System

Question 9

define the ways in which the system resources are used to solve the computing problems of the users

Answer 9

Application Programs

Question 10

People, machines, other computers

Answer 10

Users

Question 11

All temporary computer designs are based on VON NEUMANN Architecture

Answer 11

True

Question 12

Data & instructions are stored in a single read-write memory
* Contents of memory are addressable by location
* Execution occurs in a sequential fashion

Answer 12

Key Concepts

Question 13

Decides between conflicting requests for efficient and fair resource use

Answer 13

OS is a resource allocator

Question 14

Manages all resources

Answer 14

OS is a resource allocator

Question 15

Controls execution of programs to prevent errors and improper use of the computer

Answer 15

OS is a control program

Question 16

I/O devices and the CPU can execute concurrently

Answer 16

True

Question 17

• Each device controller is in charge of a particular device type

Answer 17

true

Question 18

• Each device controller has a local buffer

Answer 18

true

Question 19

• CPU moves data from/to main memory to/from local buffers

Answer 19

true

Question 20

• I/O is from the device to local buffer of controller
• Device controller

Answer 20

true

Question 21

informs CPU that it has finished its operation by causing an interrupt

Answer 21

true

Question 22

Components of a Modern OS

Answer 22

Storage management
Device Management
Memory Management
File Management
Process Management

Question 23

Interrupt transfers control to the interrupt service routine generally, through the
interrupt vector, which contains the addresses of all the service routines

Answer 23

true

Question 24

must save the address of the interrupted instruction

Answer 24

interrupt architecture

Question 25

Incoming interrupts are disabled while another interrupt is being processed to prevent a lost interrupt

Answer 25

true

Question 26

An operating system is ____________ ______________

Answer 26

interrupt driven

Question 27

is a software-generated interrupt caused either by an error or a user request

Answer 27

trap

Question 28

preserves the state of the CPU by storing registers and the program counter

Answer 28

Operating System Interrupt Handling

Question 29

Determines which type of interrupt has occurred

Answer 29

polling vectored - interrupt system Interrupt Handling

Question 30

Separate segments of code determine what action should be taken for each type of interrupt

Answer 30

Interrupt Handling

Question 31

After I/O starts, control returns to user program only upon 1/0 completion * Wait instruction idles the CPU until the next interrupt * Wait loop (contention for memory access) * At most one I/O request is outstanding at a time, no simultaneous I/O processing

Answer 31

true

Question 32

After I/O starts, control returns to user program without waiting for 1/0 completion

Answer 32

I/O structure

Question 33

request to the operating system to allow user to wait for 1/0 completion

Answer 33

* System call

Question 34

■ contains entry for each 1/O device indicating its type, address, and state

Answer 34

Device-status table

Question 35

* Operating system indexes into I/O device table to determine device status and to modify table entry to include interrupt

Answer 35

true

Question 36

Used for high-speed I/O devices able to transmit information at close to memory speeds

Answer 36

direct memory access structure

Question 37

transfers blocks of data from buffer storage directly to main memory without CPU intervention

Answer 37

direct memory access device controller

Question 38

* Only one interrupt is generated per block, rather than the one interrupt per byte

Answer 38

true

Question 39

only large storage media that the CPU can access directly

Answer 39

Main Memory

Question 40

extension of main memory that provides large nonvolatile storage capacity

Answer 40

secondary storage

Question 41

rigid metal or glass platters covered with magnetic recording material

Answer 41

magnetic disks

Question 42

is logically divided into tracks, which are subdivided into sectors

Answer 42

disk surface

Question 43

Disk surface is logically divided into ______, which are subdivided into _______

Answer 43

tracks sectors

Question 44

determines the logical interaction between the device and the computer

Answer 44

disk controller

Question 45

systems organized in hierarchy

Answer 45

speed cost volatility

Question 46

copying information into faster storage system; main memory can be viewed as a last cache for secondary storage

Answer 46

caching

Question 47

Important principle, performed at many levels in a computer (in hardware, operating system, software)

Answer 47

caching

Question 48

* Information in use copied from slower to faster storage temporarily

Answer 48

caching

Question 49

Faster storage (cache) checked first to determine if information is there * If it is, information used directly from the cache (fast) If not, data copied to cache and used there

Answer 49

true

Question 50

Cache smaller than storage being cached Cache management important design problem Cache size and replacement policy

Answer 50

true

Question 51

Most systems use a single general-purpose processor (PDAs through mainframes)

Answer 51

TRUE

Question 52

Most systems have special-purpose processors as well

Answer 52

TRUE

Question 53

Multiprocessors systems growing in use and importance

Answer 53

TRUE

Question 54

Also known as parallel systems, tightly- coupled systems

Answer 54

MULTIPROCESSOR SYSTEMS

Question 55

Multiprocessors systems growing in use and importance * Also known as parallel systems, tightly- coupled systems * Advantages include Increased throughput Economy of scale ■ Increased reliability - graceful degradation or fault tolerance

Answer 55

TRUE

Question 56

2 TYPES OF MULTIPROCESSING

Answer 56

ASYMMETRIC MULTI PROCESSING SYMMETRIC MULTIPROCESSING

Question 57

Asymmetric Multiprocessing is a multiprocessor computer system where not all of the multiple interconnected central processing units (CPUs) are treated equally.

Answer 57

Asymmetric Multiprocessing

Question 58

is the processing of programs by multiple processors that share a common operating system and memory.

Answer 58

Symmetric Multiprocessing