Direct Memory Access (DMA): Enhance Input/Output Performance in Operating Systems

Question 1

Direct Memory Access (DMA) primarily enhances:

Accepted Answer

Data transfer between devices and memory

Answer

Allocation and deallocation of memory resources

Answer

Communication between CPU and peripherals

Answer

Error checking during data transfer

Question 2

What is the purpose of a DMA channel?

Accepted Answer

Providing a dedicated pathway for data transfer between devices and memory

Answer

Arbitrating system bus access

Answer

Translating device commands into CPU instructions

Answer

Storing data during DMA operations

Question 3

What is the primary advantage of burst mode transfer in DMA?

Accepted Answer

Increased data transfer rates

Answer

Reduced latency

Answer

Simplified hardware design

Answer

Enhanced transmission reliability

Question 4

Which of these is NOT a potential drawback of DMA?

Accepted Answer

Enhanced security

Answer

Increased system complexity

Answer

Reduced CPU control over data transfers

Answer

Potential for data corruption

Question 5

Which of the following is the primary advantage of using Direct Memory Access (DMA) in operating systems?

Accepted Answer

Reduced CPU utilization during data transfer

Answer

Enhanced data transfer speed between devices and memory

Answer

Improved memory management efficiency

Answer

Increased system stability and reliability

Question 6

What is the primary function of a DMA controller in a computer system?

Accepted Answer

To manage and control data transfer directly between input/output devices and memory

Answer

To handle interrupt requests generated by devices

Answer

To provide a graphical interface for configuring devices

Answer

To convert data from one format to another

Question 7

What is the main purpose of a DMA channel in a DMA system?

Accepted Answer

To define the specific data path used for DMA transfers

Answer

To establish the priority of data transfer requests from devices

Answer

To determine the maximum data transfer rate

Answer

To handle error correction during data transfer

Question 8

What is the main purpose of using a scatter-gather DMA list?

Accepted Answer

To facilitate data transfer across multiple non-contiguous memory blocks

Answer

To prioritize data transfer requests based on importance

Answer

To reduce the overhead associated with setting up multiple DMA transfers

Answer

To improve error handling capabilities during data transfer

Question 9

Which of the following devices typically utilizes DMA for efficient data transfer?

Accepted Answer

Hard disk drive

Answer

Keyboard

Answer

Mouse

Answer

Printer

Question 10

True or False: DMA is only supported by operating systems that employ a monolithic kernel architecture.

Accepted Answer

False

Answer

True

Question 11

What is the primary objective of Direct Memory Access (DMA)?

Accepted Answer

To facilitate direct data transfer between devices and memory, bypassing the CPU

Answer

To handle interrupt requests generated by DMA-capable devices

Answer

To ensure synchronization between the CPU and DMA operations

Answer

To optimize the allocation of memory for DMA operations

Question 12

Which data transfer method is NOT supported by DMA?

Accepted Answer

Programmed Input/Output (PIO) mode

Answer

Burst mode

Answer

Cycle stealing

Answer

Block transfer mode

Question 13

What is the primary purpose of a DMA channel?

Accepted Answer

To establish a dedicated communication pathway between a DMA controller and a specific device

Answer

To store intermediate data during DMA data transfers

Answer

To regulate the flow of data between the CPU and memory during DMA operations

Answer

To provide an interrupt handling mechanism for DMA devices

Question 14

Which of the listed devices typically does NOT utilize DMA?

Accepted Answer

Central Processing Unit (CPU)

Answer

Network interface card

Answer

Graphics processing unit

Answer

Sound card

Question 15

How does DMA interact with interrupt handling in an operating system?

Accepted Answer

DMA operations can trigger interrupt requests when data transfer is complete or encounters errors

Answer

Interrupts are used to initiate DMA data transfers by signaling the DMA controller

Answer

DMA controllers can handle interrupt requests generated by other devices, freeing up the CPU

Answer

DMA operations are not associated with interrupt handling in any way

Question 16

How does the DMA controller ensure memory protection during data transfers?

Accepted Answer

Monitors address range and restricts unauthorized access

Answer

Encrypts data before transfer

Answer

Uses buffering for temporary data storage

Answer

Employs a watchdog timer for data integrity monitoring

Question 17

To enhance data throughput, which DMA optimization technique utilizes multiple DMA channels simultaneously?

Accepted Answer

Channel Multiplexing

Answer

Scatter-Gather

Answer

Bus Mastering

Answer

Cycle Stealing

Question 18

What is the fundamental purpose of Direct Memory Access (DMA) in operating systems?

Accepted Answer

Optimizing data transfer between devices and memory

Answer

Managing system-wide memory allocation

Answer

Facilitating inter-process communication

Answer

Handling hardware interrupts

Question 19

What is the role of DMA controllers within an operating system?

Accepted Answer

Coordinating data transfers between devices and memory

Answer

Managing virtual memory

Answer

Handling system-generated interrupts

Answer

Providing security measures

Question 20

How do operating systems safeguard against unauthorized memory access during DMA transfers?

Accepted Answer

Implementing memory protection mechanisms

Answer

Employing access control lists

Answer

Encrypting data

Answer

Disabling DMA

Question 21

Which of the following is NOT a primary function of a DMA controller?

Accepted Answer

Error correction

Answer

Managing data flow

Answer

Initiating data transfer

Answer

Handling interrupts

Question 22

Direct Memory Access enables data transfer between

Accepted Answer

I/O devices and main memory

Answer

Registers and I/O devices

Answer

Memory and memory cache

Answer

CPU and main memory

Question 23

The main advantage of DMA over programmed I/O is

Accepted Answer

Improved data transfer rates

Answer

Simplified programming

Answer

Enhanced security

Answer

Reduced memory usage

Question 24

Which of the following is a DMA transfer mode?

Accepted Answer

Cycle stealing

Answer

Bank switching

Answer

Protection mode

Answer

Paging

Question 25

Function of a DMA channel is to

Accepted Answer

Provide a dedicated path for DMA data transfer

Answer

Synchronize I/O devices

Answer

Store data during transfer

Answer

Translate addresses

Question 26

A potential disadvantage of DMA is

Accepted Answer

Increased system complexity

Answer

Increased power consumption

Answer

Reduced data integrity

Answer

Slowed down data transfer

Question 27

In DMA, the DMA controller

Accepted Answer

Supervises and coordinates the entire data transfer process

Answer

Reads data from memory

Answer

Writes data to I/O devices

Question 28

Operating system concept closely related to DMA

Accepted Answer

Interrupts

Answer

Deadlock

Answer

Paging

Answer

Threading

Question 29

The primary purpose of using buffers in DMA is

Accepted Answer

Temporarily storing data during transfer

Answer

Synchronizing data streams

Answer

Translating data addresses

Answer

Protecting memory from corruption

Question 30

Typical application of DMA in computer systems

Accepted Answer

Transferring data from network cards to memory

Answer

Managing user input from keyboard

Answer

Performing mathematical calculations

Answer

Updating file system metadata