MindMap Gallery operating system scheduling algorithm
This is a mind map about operating system scheduling algorithms, including short job priority SJF: Disadvantages: It is not good for long jobs, may lead to starvation, and it is difficult to achieve true short job priority.
Edited at 2022-03-24 16:37:55This mind map, titled What is a Limit, provides a structured overview of the core concept of limits, including formal definitions, intuitive understanding, one-sided vs. two-sided limits, limits at infinity, infinite limits, conditions for existence or failure, indeterminate forms, evaluation techniques, and the relationship between limits and continuity. The mind map begins with “What is a Limit,” establishing limits as describing a function’s behavior near a point. Intuitive understanding builds a formal picture through the ε ε strip and δ δ neighborhood. One-sided and two-sided limits clarify conditions for limit existence. When limits exist or fail covers jumps, oscillations, and infinite behavior. Limits at infinity and infinite limits are distinguished. Indeterminate forms highlight why extra work is needed beyond direct substitution. Techniques to evaluate limits include direct substitution, algebraic simplification, geometric limits, the squeeze (sandwich) theorem, and techniques for handling infinity. Continuity is defined in terms of limits, with the condition that the limit equals the function value at a point. Typical misconceptions are addressed to clarify foundational understanding. Designed for students and practitioners in mathematics, physics, engineering, and the sciences, this template offers a clear conceptual framework for understanding limits as the foundation of calculus.
Explore the fundamental concepts of work and power, essential for understanding energy dynamics in physics. This overview covers core definitions, including work as energy transfer and power as the rate of work done. Delve into the work-energy relation, examining the work-kinetic energy theorem and the distinctions between conservative and nonconservative forces. Learn how to calculate work under various conditions, from constant forces to variable forces and multiple interactions. The mechanical energy framework explains energy conservation principles, while power calculations provide insight into energy transfer rates. Utilize graphical tools and diagrams to visualize these concepts, avoiding common pitfalls in understanding work and its implications.
Discover the fascinating world of isotopes, the variants of chemical elements that share the same number of protons but differ in neutrons, leading to unique properties. This overview covers the core definitions and atomic structure basics of isotopes, including their notation and abundance. Learn about examples like hydrogen, carbon, and oxygen, and differentiate between stable isotopes and radioisotopes. Understand the significance of isotopic variation, its origins in stellar processes and fractionation, and how we measure isotopes using advanced techniques like mass spectrometry. Join us in exploring the critical role isotopes play in science and nature.
This mind map, titled What is a Limit, provides a structured overview of the core concept of limits, including formal definitions, intuitive understanding, one-sided vs. two-sided limits, limits at infinity, infinite limits, conditions for existence or failure, indeterminate forms, evaluation techniques, and the relationship between limits and continuity. The mind map begins with “What is a Limit,” establishing limits as describing a function’s behavior near a point. Intuitive understanding builds a formal picture through the ε ε strip and δ δ neighborhood. One-sided and two-sided limits clarify conditions for limit existence. When limits exist or fail covers jumps, oscillations, and infinite behavior. Limits at infinity and infinite limits are distinguished. Indeterminate forms highlight why extra work is needed beyond direct substitution. Techniques to evaluate limits include direct substitution, algebraic simplification, geometric limits, the squeeze (sandwich) theorem, and techniques for handling infinity. Continuity is defined in terms of limits, with the condition that the limit equals the function value at a point. Typical misconceptions are addressed to clarify foundational understanding. Designed for students and practitioners in mathematics, physics, engineering, and the sciences, this template offers a clear conceptual framework for understanding limits as the foundation of calculus.
Explore the fundamental concepts of work and power, essential for understanding energy dynamics in physics. This overview covers core definitions, including work as energy transfer and power as the rate of work done. Delve into the work-energy relation, examining the work-kinetic energy theorem and the distinctions between conservative and nonconservative forces. Learn how to calculate work under various conditions, from constant forces to variable forces and multiple interactions. The mechanical energy framework explains energy conservation principles, while power calculations provide insight into energy transfer rates. Utilize graphical tools and diagrams to visualize these concepts, avoiding common pitfalls in understanding work and its implications.
Discover the fascinating world of isotopes, the variants of chemical elements that share the same number of protons but differ in neutrons, leading to unique properties. This overview covers the core definitions and atomic structure basics of isotopes, including their notation and abundance. Learn about examples like hydrogen, carbon, and oxygen, and differentiate between stable isotopes and radioisotopes. Understand the significance of isotopic variation, its origins in stellar processes and fractionation, and how we measure isotopes using advanced techniques like mass spectrometry. Join us in exploring the critical role isotopes play in science and nature.
Scheduling Algorithm
First come first serve FCFS
Non-preemptive
Advantages: Simple to implement, fair
Disadvantages: Not good for short jobs
Consider waiting time & running time
Waiting time√
Running time ×
hunger
Won't
Short jobs first SJF
Default: non-preemptive
Pros: "Shortest" average time/turnaround time
Disadvantages: Unfavorable for long jobs, may lead to starvation, and it is difficult to truly prioritize short jobs
Preemptive: shortest remaining time first algorithm SRTN
Consider waiting time & running time
Waiting time ×
Running time√
hunger
meeting
High response ratio priority HRRN
Non-preemptive
Advantages: FCFS, SJF compromise, taking into account waiting time and running time
Preemptive
Consider waiting time & running time
Waiting time√
Running time√
hunger
Won't
Time slice rotation (RR)
Preemptive
Advantages: Fair, fast response, suitable for time-sharing operating systems
Disadvantages: Due to high frequency of process switching, there is a certain overhead, and the urgency of the task is not distinguished.
hunger
Won't
Evaluation indicators of scheduling algorithms
Response time
Time from user submission to first response
Response ratio = waiting time time required for service/time required for service
waiting time
Process/job = sum of time waiting to be served
Average waiting time = process/job = average waiting time
CPU utilization
Utilization = busy time/total time
System throughput
System throughput = total number of jobs completed/total time spent
Turnaround time
Turnaround time = job completion time – job submission time
Average turnaround time = sum of turnaround times for each job/number of jobs
Weighted turnaround time = job turnaround time / actual running time of the job
Average weighted turnaround time = sum of weighted turnaround times for each job/number of jobs
priority scheduling algorithm
Preemptive, non-preemptive
Advantages: Use priority to distinguish urgency and importance, suitable for real-time operating systems, and can flexibly adjust the preference for various jobs/processes
Disadvantages: If there is a continuous flow of high-priority processes, it may lead to starvation.
hunger
meeting
Multi-level feedback queue scheduling algorithm
Preemptive
Advantages: Compromise of all algorithms
Advantages: Fair (FCFS), new processes are responded to quickly (RR), short processes take less time to complete (SPF), flexible adjustment of preferences for various processes
Disadvantages: None
hunger
meeting
Early batch processing systems
interactive system
process scheduling
Process and job scheduling