Processor Management Chapter 4

Questions and Answers

What is aging?

A policy used to ensure that jobs that have been in the system for a long time in the lower-level queues will eventually complete their execution.

What is context switching?

The act of saving a job's processing information in its PCB so the job can be swapped out of memory and loading the processing information from the PCB of another job.

What is a CPU-bound job?

A job that will perform a great deal of nonstop processing before issuing an interrupt.

What does FCFS stand for?

First Come, First Served. Signup and view all the answers

What is an I/O-bound job?

A job that requires a large number of input/output operations. Signup and view all the answers

What is indefinite postponement?

A delay in a job's execution because it is repeatedly preempted by other jobs. Signup and view all the answers

What is an interrupt?

A hardware signal that suspends execution of a program. Signup and view all the answers

What is an interrupt handler?

The program that controls what action should be taken by the operating system when an event is interrupted. Signup and view all the answers

What is a job scheduler?

The high-level scheduler of the processor manager that selects jobs from a queue. Signup and view all the answers

What does job status indicate?

The condition of a job as it moves through the system from beginning to end of its execution. Signup and view all the answers

What is a middle-level scheduler?

A scheduler used to manage processes that have been interrupted because they exceeded their allocated CPU time slice. Signup and view all the answers

What are multiple-level queues?

A process scheduling scheme that groups jobs according to a common characteristic. Signup and view all the answers

What does multiprogramming allow?

Allows a single processor to process several programs residing simultaneously in main memory. Signup and view all the answers

What is a natural wait?

An I/O request from a program in a multiprogramming environment that would cause a process to wait 'naturally.' Signup and view all the answers

What is a nonpreemptive scheduling policy?

A job scheduling strategy that functions without external interrupts. Signup and view all the answers

What is a preemptive scheduling policy?

Any process scheduling strategy that interrupts a job to transfer CPU to another job. Signup and view all the answers

What is priority scheduling?

A nonpreemptive process scheduling policy that allows high-priority jobs to execute before low-priority jobs. Signup and view all the answers

What is a process?

An instance of execution of a program that is identifiable and controllable by the operating system. Signup and view all the answers

What is a Process Control Block (PCB)?

A data structure containing information about the current status and characteristics of a process. Signup and view all the answers

What is a Process scheduler?

The low-level scheduler that establishes the order of processes in the READY queue. Signup and view all the answers

What is a process scheduling algorithm?

An algorithm used by the Job Scheduler to allocate the CPU and move jobs through the system. Signup and view all the answers

What is a process scheduling policy?

Any policy used by the Processor Manager to select the order in which jobs will be executed. Signup and view all the answers

What does process status indicate?

Information stored in the job's PCB that indicates the current position of the job. Signup and view all the answers

What is a processor?

(1) A synonym for the CPU; (2) Any component capable of performing a sequence of activities. Signup and view all the answers

What is a program?

An interactive unit, such as a file stored on a disk. Signup and view all the answers

What is a queue?

A linked list of PCBs that indicates the order in which jobs or processes will be serviced. Signup and view all the answers

Study Notes

Processor Management Key Concepts

Aging: Ensures long-waiting jobs in lower-level queues eventually complete their execution.
Context Switching: Involves saving a job's state in its Process Control Block (PCB) and loading another job's state for CPU processing; vital in preemptive scheduling.
CPU-bound Jobs: Characterized by extensive processing before producing interrupts, requiring significant CPU time.
First Come, First Served (FCFS): A nonpreemptive scheduling algorithm that processes jobs based on their arrival time.
I/O-bound Jobs: Depend on numerous input/output operations, leading to significant idle CPU time.
Indefinite Postponement: Occurs when a job is delayed forever due to continuous preemption by other jobs.
Interrupt: A hardware signal that halts a program's execution, triggering the interrupt handler.
Interrupt Handler: Manages the actions taken by the operating system in response to interrupts.
Job Scheduler: A high-level component that selects jobs for processing based on their characteristics from incoming queues.
Job Status: Represents the condition of a job throughout its execution lifecycle, from start to completion.
Middle-level Scheduler: Manages processes that have been interrupted for exceeding CPU time slices.
Multiple-level Queues: A scheduling strategy categorizing jobs based on shared features.
Multiprogramming: Enables a single processor to run multiple programs simultaneously by overlapping I/O and CPU tasks.
Natural Wait: Refers to the waiting period of a program in response to I/O requests in a multiprogramming context.
Nonpreemptive Scheduling Policy: Jobs run to completion once started, without being interrupted until they submit an I/O request or finish.
Preemptive Scheduling Policy: Allows the interruption of jobs based on set criteria, commonly used in time-sharing systems.
Priority Scheduling: A nonpreemptive method prioritizing high-priority jobs over lower-priority ones.
Process: An instance of a program in execution, monitored and managed by the operating system.
Process Control Block (PCB): Contains details regarding a process's current status and attributes.
Process Scheduler: A low-level scheduler that orders processes in the READY queue for CPU servicing.
Process Scheduling Algorithm: Algorithms that determine how the job scheduler allocates CPU time and manages job execution.
Process Scheduling Policy: Guidelines utilized by the processor manager for the order of job execution.
Process Status: Information tracked in the PCB detailing a job's current position and resource usage.
Processor: Refers to the CPU or any component capable of executing sequences of operations.
Program: An interactive unit, such as a file located on a disk.
Queue: A linked list of PCBs indicating the sequence in which jobs or processes will be serviced.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz consists of flashcards focused on key concepts within Processor Management, specifically from Chapter 4. It includes important definitions such as aging and context switching that are essential for understanding job scheduling and resource management in an operating system.