Question 1

Scheduling strategies are commonly evaluated by the system's ________.

Accepted Answer

A)  throughput 
B)  mean response time 
C)  variance of response times 
D)  all of the above 
A)  throughput 
B)  mean response time 
C)  variance of response times 
D)  all of the above

Question 2

The primary advantage of F-SCAN scheduling over other SCAN strategies is ________.

Accepted Answer

A)  improved seek time 
B)  reduced variance in response times 
C)  avoidance of indefinite postponement 
D)  both b and c 
A)  improved seek time 
B)  reduced variance in response times 
C)  avoidance of indefinite postponement 
D)  both b and c

Question 3

The most significant bottleneck in RAID level 4 is its ________.

Accepted Answer

A)  read performance 
B)  write performance 
C)  parity generation 
D)  both b and c 
A)  read performance 
B)  write performance 
C)  parity generation 
D)  both b and c

Question 4

________ is the amount of time required for the head to move from its current cylinder to its destination.

Accepted Answer

A)  Rotational latency time 
B)  Transmission time 
C)  Seek time 
D)  none of the above 
A)  Rotational latency time 
B)  Transmission time 
C)  Seek time 
D)  none of the above

Question 5

RAID level 2 schemes ________.

Accepted Answer

A)  offer higher throughput than RAID level 0 
B)  are more space-efficient than RAID level 1 
C)  are rarely implemented 
D)  both b and c 
A)  offer higher throughput than RAID level 0 
B)  are more space-efficient than RAID level 1 
C)  are rarely implemented 
D)  both b and c

Question 6

In SLTF scheduling, requests are ordered by ________, with the ________ one being serviced first.

Accepted Answer

A)  track, nearest 
B)  size, largest 
C)  sector, nearest 
D)  size, smallest 
A)  track, nearest 
B)  size, largest 
C)  sector, nearest 
D)  size, smallest

Question 7

Today's hard disks counteract efforts to improve performance using disk scheduling ________.

Accepted Answer

A)  by using alternate sectors dispersed throughout the disk to improve reliability 
B)  because little effort has been made to increase disk rotational speeds 
C)  reordering disk requests 
D)  all of the above 
A)  by using alternate sectors dispersed throughout the disk to improve reliability 
B)  because little effort has been made to increase disk rotational speeds 
C)  reordering disk requests 
D)  all of the above

Question 8

Magnetic storage became popular because it was ________.

Accepted Answer

A)  fast, inexpensive and persistent 
B)  rewritable, inexpensive and persistent 
C)  rewritable, fast and persistent 
D)  inexpensive, fast and reliable 
A)  fast, inexpensive and persistent 
B)  rewritable, inexpensive and persistent 
C)  rewritable, fast and persistent 
D)  inexpensive, fast and reliable

Question 9

The original motivation for RAID came from the observation that ________.

Accepted Answer

A)  main memory was faster than secondary storage 
B)  disk capacities were increasing, but disk I/O transfer rates were increasing at a much slower pace 
C)  disks were becoming increasingly susceptible to failures 
D)  all of the above 
A)  main memory was faster than secondary storage 
B)  disk capacities were increasing, but disk I/O transfer rates were increasing at a much slower pace 
C)  disks were becoming increasingly susceptible to failures 
D)  all of the above

Question 10

SCAN disk scheduling considers ________ in addition to seek times.

Accepted Answer

A)  rotational latency 
B)  direction 
C)  variance of response times 
D)  transmission time 
A)  rotational latency 
B)  direction 
C)  variance of response times 
D)  transmission time

Question 11

Both SPTF and SATF scheduling can lead to ________.

Accepted Answer

A)  low throughput 
B)  high mean response times 
C)  high variance of response times 
D)  indefinite postponement 
A)  low throughput 
B)  high mean response times 
C)  high variance of response times 
D)  indefinite postponement

Question 12

Because SSTF scheduling exhibits high ________, it is inappropriate for real-time and interactive systems.

Accepted Answer

A)  variance of response times 
B)  throughput 
C)  mean response time 
D)  both a and b 
A)  variance of response times 
B)  throughput 
C)  mean response time 
D)  both a and b

Question 13

One technique that can improve RAID level 5 performance, called ________, involves performing a read-modify-write cycle only when the system load is light.

Accepted Answer

A)  AFRAID 
B)  write combining 
C)  update imaging 
D)  parity logging 
A)  AFRAID 
B)  write combining 
C)  update imaging 
D)  parity logging

Question 14

FCFS scheduling does not exhibit ________.

Accepted Answer

A)  high throughput 
B)  indefinite postponement of requests 
C)  low variance of response times 
D)  both a and b 
A)  high throughput 
B)  indefinite postponement of requests 
C)  low variance of response times 
D)  both a and b

Question 15

N-Step SCAN differs from F-SCAN in that ________.

Accepted Answer

A)  N-Step SCAN prevents indefinite postponement, but F-SCAN does not. 
B)  N-Step SCAN always provides higher throughput than F-SCAN, but results in a larger variance in response times. 
C)  N-Step SCAN selects requests it will service during the current sweep according to the number of requests; F-SCAN selects such requests according to time. 
D)  None of the above-N-Step SCAN and F-SCAN are identical. 
A)  N-Step SCAN prevents indefinite postponement, but F-SCAN does not. 
B)  N-Step SCAN always provides higher throughput than F-SCAN, but results in a larger variance in response times. 
C)  N-Step SCAN selects requests it will service during the current sweep according to the number of requests; F-SCAN selects such requests according to time. 
D)  None of the above-N-Step SCAN and F-SCAN are identical.

Question 16

Disks in RAID level 4 are ________.

Accepted Answer

A)  striped at the bit level 
B)  striped at the block level 
C)  less fault tolerant than RAID level 3 
D)  both b and c 
A)  striped at the bit level 
B)  striped at the block level 
C)  less fault tolerant than RAID level 3 
D)  both b and c

Question 17

Moving-head disks store data in ________, which are part of larger units called _______, which form ________ when considered vertically.

Accepted Answer

A)  tracks, sectors, cylinders 
B)  sectors, cylinders, tracks 
C)  cylinders, tracks, sectors 
D)  sectors, tracks, cylinders 
A)  tracks, sectors, cylinders 
B)  sectors, cylinders, tracks 
C)  cylinders, tracks, sectors 
D)  sectors, tracks, cylinders

Question 18

Disk cache buffers are stored ________.

Accepted Answer

A)  in main memory 
B)  in a memory module attached to the disk drive 
C)  on a disk interface controller 
D)  all of the above 
A)  in main memory 
B)  in a memory module attached to the disk drive 
C)  on a disk interface controller 
D)  all of the above

Question 19

FCFS scheduling tends to result in an acceptable amount of ________ at the expense of ________.

Accepted Answer

A)  throughput, fairness 
B)  variance of response times, fairness 
C)  variance of response times, throughput 
D)  fairness, variance of response times 
A)  throughput, fairness 
B)  variance of response times, fairness 
C)  variance of response times, throughput 
D)  fairness, variance of response times

Question 20

A primary drawback to RAID schemes is greatly decreased ________.

Accepted Answer

A)  performance 
B)  mean-time-to-failure 
C)  disk space 
D)  redundancy 
A)  performance 
B)  mean-time-to-failure 
C)  disk space 
D)  redundancy

Exam 12: Disk Storage and Raid Technology

Scheduling strategies are commonly evaluated by the system's ________.

The primary advantage of F-SCAN scheduling over other SCAN strategies is ________.

The most significant bottleneck in RAID level 4 is its ________.

________ is the amount of time required for the head to move from its current cylinder to its destination.

RAID level 2 schemes ________.

In SLTF scheduling, requests are ordered by ________, with the ________ one being serviced first.

Today's hard disks counteract efforts to improve performance using disk scheduling ________.

Magnetic storage became popular because it was ________.

The original motivation for RAID came from the observation that ________.

SCAN disk scheduling considers ________ in addition to seek times.

Both SPTF and SATF scheduling can lead to ________.

Because SSTF scheduling exhibits high ________, it is inappropriate for real-time and interactive systems.

One technique that can improve RAID level 5 performance, called ________, involves performing a read-modify-write cycle only when the system load is light.

FCFS scheduling does not exhibit ________.

N-Step SCAN differs from F-SCAN in that ________.

Disks in RAID level 4 are ________.

Moving-head disks store data in ________, which are part of larger units called _______, which form ________ when considered vertically.

Disk cache buffers are stored ________.

FCFS scheduling tends to result in an acceptable amount of ________ at the expense of ________.

A primary drawback to RAID schemes is greatly decreased ________.

Exploring Operating Systems and Distributed Computing: a Comprehensive Overview

Understanding Computer Systems and Programming Concepts

Understanding Processes and Threads in Operating Systems

Exploring Semaphores and Multithreading in Operating Systems

Exploring Thread Synchronization and Mutual Exclusion in Java

Concurrency and Deadlock in Database Systems: Exploring Monitor Implementation and Thread Synchronization in Java

Operating System Scheduling and Deadlock Prevention: a Comprehensive Guide

Understanding Processor Scheduling and Memory Management in Operating Systems

Memory Management in Operating Systems: Segmentation, Paging, and Strategies for Efficiency

Memory Management and Address Translation in Operating Systems

Memory Management and Page Replacement Strategies in Operating Systems

Understanding File Systems and Database Systems: a Comprehensive Overview

Exploring Performance Evaluation and Benchmarking in Computer Systems

Understanding Multiprocessor Organizations and System Performance

Understanding the Layers of the TCP/IP Protocol Stack

Understanding Distributed Systems and Operating Systems

Exploring Distributed File Systems and Grid Computing With NFS, AFS, Coda, and JXTA

Security Threats and Solutions in Cryptography and Access Control

Exploring the Linux Operating Systems Features and Functionality

In-Depth Analysis of Windows XP

Filters

In SLTF scheduling, requests are ordered by , with the one being serviced first.

Moving-head disks store data in ____, which are part of larger units called _, which form ______ when considered vertically.

FCFS scheduling tends to result in an acceptable amount of at the expense of .