Deck 4: Processor Management

Question 1

From HOLD, the job moves to WAITING when it's ready to run but is waiting for the CPU.

Answer 1

False

Question 2

It is possible to minimize response time by running only interactive jobs and letting the batch jobs wait until the interactive load ceases.

Answer 2

True

Question 3

A single processor can be shared by several jobs, or several processes, but if, and only if, the operating system has a scheduling policy, as well as a scheduling algorithm, to determine when to stop working on one job and proceed to another.

Answer 3

True

Question 4

The Process Scheduler often uses a timing mechanism and periodically interrupts running processes when a predetermined slice of time has expired.

Question 5

A process is an inactive unit, such as a file stored on a disk.

Question 6

The Processor Manager is a composite of two submanagers: one in charge of job scheduling and the other in charge of program scheduling.

Question 7

The transition from one job or process status to another is initiated by either the Job Scheduler or the Process Scheduler.

Question 8

Shortest job next (SJN) is a nonpreemptive scheduling algorithm (also known as shortest job first, or SJF) that handles jobs based on the length of their CPU cycle time.

Question 9

A program is an active entity that requires a set of resources, including a processor and special registers, to perform its function.

Question 10

First-come, first-served (FCFS) is a preemptive scheduling algorithm that handles jobs according to their arrival time.

Question 11

The processor is also known as the CPU.

Question 12

If one job monopolizes the system, the extent of its overall effect on system performance depends on the scheduling policy and whether the job is CPU-bound or I/O-bound.

Question 13

When using priority scheduling, priorities are assigned to jobs by the owner of the job (the user).

Question 14

CPU-bound jobs (such as printing a series of documents) have many brief CPU cycles and long I/O cycles.

Question 15

The shortest remaining time (SRT) algorithm is often used in interactive systems.

Question 16

The process state contains all of the data about the job needed by the operating system to manage the processing of the job.

Question 17

Each job is uniquely identified by the user's identification and a pointer connecting it to its descriptor.

Question 18

As a job moves through the system it is always in one of five states (or at least three); these are called the job status or the process status.

Question 19

After a job has been placed on the READY queue by the Job Scheduler, the Process Scheduler takes over.

Question 20

Most computer programs alternate between CPU cycles and I/O cycles.

Question 21

The transition from ____ is initiated by the Process Scheduler or the Job Scheduler.

A) WAITING to READY
B) RUNNING to WAITING
C) RUNNING to FINISHED
D) HOLD to READY

Question 22

First-come, first-served (FCFS) is a very simple algorithm to implement because it ____.

A) uses a FIFO queue
B) uses a LIFO queue
C) uses a circular queue
D) uses a directed graph

Question 23

When the job is accepted by the system, it's put on ____ and placed in a queue.

A) HOLD
B) RUNNING
C) WAITING
D) READY

Question 24

____ contains information used mainly for billing purposes and performance measurement.

A) Accounting
B) Process State
C) Process Identification
D) Process Status

Question 25

A ____ is a portion of a process that can run independently.

A) thread
B) program
C) miniprocess
D) subprocess

Question 26

The Process Scheduler assigns the CPU to execute the processes of those jobs placed on the ____ queue by the Job Scheduler.

A) WAITING
B) NEXT
C) PROCESS
D) READY

Question 27

The control program that handles the interruption sequence of events is called the interrupt scheduler.

Question 28

Assume that four jobs A-D require the CPU cycles listed below. Using the SJN algorithm, the ____ job is run first. Job: A B C D
CPU cycle: 5 2 6 4

A) A
B) B
C) C
D) D

Question 29

The first-come, first-served (FCFS) algorithm is fine for most ____ systems.

A) multiuser
B) user initied
C) interactive
D) batch

Question 30

An I/O request is called a(n) ____ wait in multiprogramming environments.

A) forced
B) natural
C) scheduled
D) indirect

Question 31

Queues use ____ to track jobs the same way customs officials use passports to track international visitors.

A) jobs
B) processes
C) PCBs
D) record identifiers

Question 32

____ holds pertinent information, including the address where the job is stored and, in the case of virtual memory, the mapping between virtual and physical memory locations.

A) Main memory
B) Register content
C) Process priority
D) The process state

Question 33

The ____ is also called the high-level scheduler.

A) Process Scheduler
B) Job Scheduler
C) Program Scheduler
D) Thread Scheduler

Question 34

Multiple-level queues isn't really a separate scheduling algorithm but works in conjunction with several other schemes.

Question 35

In a highly interactive environment there is a third layer of the Processor Manager called the ____ scheduler.

A) Managing
B) Subprocess
C) middle-level
D) Program

Question 36

The Job Scheduler seeks to ___ , when scheduling jobs.

A) Run all CPU intensive jobs first.
B) Run all I/O intensive jobs first.
C) Balance CPU and I/O intensive jobs.
D) Run the quickest jobs first.

Question 37

In round robin scheduling, if processing isn't finished when time expires, the job is preempted and put at the end of the READY queue and its information is saved in its PCB.

Question 38

Aging is used to ensure that jobs in lower-level queues will eventually complete their execution.

Question 39

The transition from ____ is initiated by the Job Scheduler according to some predefined policy.

A) READY to RUNNING
B) RUNNING to WAITING
C) RUNNING back to READY
D) HOLD to READY

Question 40

Context switching is required by all preemptive algorithms.

Question 41

Assume that jobs A-D arrive in the ready queue in quick succession and have the CPU cycle requirements listed below. Using the SRT algorithm, the average turnaround time is ____. Arrival time: 0 1 2 3
Job: A B C D
CPU cycle: 6 3 1 4

A) 2.5
B) 6.25
C) 7.75
D) 9.0

Question 42

When selecting the proper time quantum it should be long enough to allow ____ percent of the CPU cycles to run to completion.

A) 20
B) 60
C) 80
D) 100

Question 43

Assume that four jobs A-D require the CPU cycles listed below. Using the SJN algorithm, the average turnaround time is ____. Job: A B C D
CPU cycle: 5 2 6 4

A) 5.5
B) 6.8
C) 9.0
D) 11.1

Question 44

____ jobs are treated like all the others once they are in the system.

A) Low-priority
B) High-priority
C) Variable-priority
D) Moving-priority

Question 45

Assume jobs A-D arrive in quick succession in the READY queue. Using round robin scheduling, the turnaround time for job C is ____. Arrival time: 0 1 2 3
Job: A B C D
CPU cycle: 8 4 9 5

A) 7
B) 20
C) 22
D) 24

Question 46

____ allows for faster turnaround of CPU-bound jobs.

A) No movement between queues
B) Movement between queues
C) Variable time quantum per queue
D) Aging

Question 47

When the operating system detects a nonrecoverable error, the following step ____, is performed first by the interrupt handler.

A) state of the interrupted process is saved
B) type of interrupt is described and stored
C) interrupt is processed
D) processor resumes operation

Question 48

Some systems increase the priority of jobs that have been in the system for an unusually long time to expedite their exit, which is known as ____.

A) lagging
B) aging
C) bumping
D) accelerated priority

Question 49

Internal interrupts, or ____ interrupts, also occur as a direct result of the arithmetic operation or job instruction currently being processed.

A) I/O
B) illegal job instruction
C) illegal operation
D) synchronous

Question 50

No movement between queues is a very simple policy that rewards those who have ____ jobs.

A) high-priority
B) low-priority
C) CPU-bound
D) I/O-bound