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The document discusses various process and thread scheduling methods. It covers the organization of schedulers, common scheduling algorithms like priority scheduling, and comparisons of scheduling methods. It also describes the priority inversion problem and solution of dynamic priority inheritance to prevent lower priority processes from indefinitely blocking higher priority processes.
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Process management
The document discusses various concepts related to process and thread scheduling in operating systems. It defines key terms like process, job, thread, context switching, and process states. It also explains different scheduling algorithms like round robin, shortest job first, priority scheduling, and multilevel feedback queue scheduling.
Operating System 5
The document discusses various CPU scheduling concepts and algorithms. It covers basic concepts like CPU-I/O burst cycles and scheduling criteria. It then describes common scheduling algorithms like first come first served (FCFS), shortest job first (SJF), priority scheduling, and round robin (RR). It also discusses more advanced topics like multi-level queue scheduling, multi-processor scheduling, and thread scheduling in Linux.
Ch05
The document discusses CPU scheduling in operating systems. It covers basic concepts like CPU bursts and scheduling criteria. It then describes common scheduling algorithms like FCFS, SJF, priority scheduling, and round robin. It also discusses thread scheduling, multiprocessor scheduling, and examples of scheduling in Solaris, Windows, and Linux.
cpu sechduling
This document summarizes key concepts in CPU scheduling, including:
1) CPU scheduling algorithms like FCFS, SJF, priority, and round robin and how they optimize different criteria.
2) The role of dispatchers in context switching between processes.
3) Scheduling criteria like CPU utilization, throughput, turnaround time.
4) Advanced scheduling techniques like multilevel queues, multilevel feedback queues, and multiprocessor scheduling.
OS_Ch6
This document discusses various CPU scheduling algorithms and concepts. It covers scheduling criteria like CPU utilization and turnaround time. Algorithms discussed include first-come first-served (FCFS), shortest job first (SJF), priority scheduling, and round robin (RR). It also covers multiple processor scheduling, real-time scheduling, and evaluating scheduling algorithms.
OSCh6
This document discusses various CPU scheduling algorithms and concepts. It covers scheduling criteria like CPU utilization and turnaround time. Algorithms discussed include first-come first-served (FCFS), shortest job first (SJF), priority scheduling, and round robin (RR). It also covers multiple processor scheduling, real-time scheduling, and evaluating scheduling algorithms.
Process management in os
1. Process management is an integral part of operating systems for allocating resources, enabling information sharing, and protecting processes. The OS maintains data structures describing each process's state and resource ownership.
2. Processes go through discrete states and events can cause state changes. Scheduling selects processes to run from ready, device, and job queues using algorithms like round robin, shortest job first, and priority scheduling.
3. CPU scheduling aims to maximize utilization and throughput while minimizing waiting times using criteria like response time, turnaround time, and fairness between processes.
Ch5
This document discusses various CPU scheduling algorithms and concepts. It covers scheduling criteria like CPU utilization and turnaround time. Algorithms discussed include first-come first-served (FCFS), shortest job first (SJF), priority scheduling, and round robin (RR). It also covers multiple queue scheduling, real-time scheduling, and ways to evaluate scheduling algorithm performance like deterministic modeling and simulation.
Ch6
CPU scheduling involves selecting which process to execute next from among processes in memory. There are several criteria for evaluating CPU scheduling algorithms, including CPU utilization, throughput, turnaround time, waiting time, and response time. Common algorithms include first-come, first-served (FCFS), shortest-job-first (SJF), priority scheduling, and round robin (RR). Multilevel queue and feedback queue scheduling involve partitioning processes into multiple queues that use different scheduling policies.
SCHEDULING ALGORITHMS
A process scheduler schedules processes for the CPU based on scheduling algorithms. There are five main algorithms: first-come, first-served; shortest job next; priority; round robin; and multiple-level queues. These algorithms are either preemptive, where a process can be interrupted, or non-preemptive. Preemptive algorithms prioritize higher priority processes, while non-preemptive ones do not interrupt running processes.
Priority Scheduling
Operating System presentation on priority Scheduling, Queue Scheduling and multi level feedback scheduling with examples.
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This document discusses periodic scheduling and handling aperiodic jobs in real-time systems. It covers periodic task scheduling approaches like static cyclic scheduling, earliest deadline first (EDF), and rate monotonic (RM) scheduling. It also discusses how to handle aperiodic jobs through fixed priority servers and dynamic priority servers. The document provides examples and compares the properties of EDF and RM scheduling algorithms. It analyzes approaches like background scheduling and polling servers for integrating periodic and aperiodic tasks.
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The document discusses Windows XP's scheduling algorithm. It uses a priority-based, preemptive approach with 32 priority levels divided into variable and real-time classes. The scheduler ensures the highest priority thread runs by maintaining queues for each priority level and traversing from highest to lowest. Threads start at the process' base priority and may have their priority lowered after time quantums expire to limit CPU consumption of compute-intensive threads.
Os..
The document discusses various scheduling algorithms used in operating systems including:
- First Come First Serve (FCFS) scheduling which services processes in the order they arrive but can lead to long wait times.
- Shortest Job First (SJF) scheduling which prioritizes the shortest processes first to minimize wait times. This can be preemptive or non-preemptive.
- Priority scheduling which assigns priorities to processes and services the highest priority first, which can cause starvation of low priority processes.
- Round Robin scheduling which allows fair sharing of the CPU by allocating a time quantum or slice to each process in a cyclic manner.
Csc4320 chapter 5 2
The document discusses various scheduling algorithms used in operating systems including:
- First Come First Serve (FCFS) scheduling which services processes in the order of arrival but can lead to long waiting times.
- Shortest Job First (SJF) scheduling which prioritizes the shortest processes first to minimize waiting times. It can be preemptive or non-preemptive.
- Priority scheduling assigns priorities to processes and services the highest priority process first, which can potentially cause starvation of low priority processes.
- Round Robin scheduling allows equal CPU access to all processes by allowing each a small time quantum before being preempted. It has lower average waiting times than FCFS but higher than SJF.
Scheduling algorithms
The document discusses various scheduling algorithms used in operating systems including:
- First Come First Serve (FCFS) scheduling which services processes in the order of arrival but can lead to long waiting times.
- Shortest Job First (SJF) scheduling which prioritizes the shortest processes first to minimize waiting times. It can be preemptive or non-preemptive.
- Priority scheduling assigns priorities to processes and services the highest priority process first, which can potentially cause starvation of low priority processes.
- Round Robin scheduling allows equal CPU access to all processes by allowing each a small time quantum or slice before preempting to the next process.
CPU scheduling
* Using SJF preemptive scheduling:
P2 will execute from time 0 to 5 ms.
P3 will execute from time 5 to 8 ms.
P1 will execute from time 8 to 18 ms.
P4 will execute from time 18 to 38 ms.
P5 will execute from time 38 to 40 ms.
Total waiting time = (10-5) + (8-5) + (18-0) + (38-5) + (40-10) = 5.6 + 3 + 18 + 33 + 30 = 90
Average waiting time = Total waiting time / Number of processes = 90/5 = 5.6 ms
* Using Priority preemptive scheduling
OS-operating systems- ch05 (CPU Scheduling) ...
operating systems , ch-05, (CPU Scheduling), 3rd level, College of Computers, Seiyun University. انظمة التشغيل لطلاب المستوى الثالث بكلية الحاسبات بجامعة سيئون المحاضرة 05
Cpu scheduling
This Presention contains Cpu scheduling algorithms,Scheduling Criteria,process sychroization,mutilevel feed back que,critical section problem anad semaphores,Synchoroniztion hardware
Ch05 cpu-scheduling
This document discusses CPU scheduling algorithms. It begins with basic concepts like multiprogramming and the alternating cycle of CPU and I/O bursts that processes undergo. It then covers key scheduling criteria like CPU utilization, throughput, waiting time and turnaround time. Several single processor scheduling algorithms are explained in detail, including first come first served (FCFS), shortest job first (SJF), priority scheduling, and round robin (RR). Examples are provided to illustrate how each algorithm works. Finally, it briefly introduces the concept of multi-level queue scheduling using multiple queues to classify different types of processes.
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