Processor scheduling algorithms

Fixed-priority pre-emptive scheduling

Fixed-priority preemptive scheduling is a scheduling system commonly used in real-time systems. With fixed priority preemptive scheduling, the scheduler ensures that at any given time, the processor executes the highest priority task of all those tasks that are currently ready to execute. The preemptive scheduler has a clock interrupt task that can provide the scheduler with options to switch after the task has had a given period to execute—the time slice. This scheduling system has the advantage of making sure no task hogs the processor for any time longer than the time slice. However, this scheduling scheme is vulnerable to process or thread lockout: since priority is given to higher-priority tasks, the lower-priority tasks could wait an indefinite amount of time. One common method of arbitrating this situation is aging, which gradually increments the priority of waiting processes and threads, ensuring that they will all eventually execute. Most real-time operating systems (RTOSs) have preemptive schedulers. Also turning off time slicing effectively gives you the non-preemptive RTOS. Preemptive scheduling is often differentiated with cooperative scheduling, in which a task can run continuously from start to end without being preempted by other tasks. To have a task switch, the task must explicitly call the scheduler. Cooperative scheduling is used in a few RTOS such as or TinyOS. * v * t * e (Wikipedia).

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Scheduling: The List Processing Algorithm Part 1

This lesson explains and provides an example of the list processing algorithm to make a schedule given a priority list. Site: http://mathispower4u.com

From playlist Scheduling

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Process Scheduling

An animation showing the main features of a process scheduling system including the ready queue, blocked queue, high level scheduler and low level scheduler. It explains the principle of a round robin scheduling algorithm.

From playlist Operating Systems

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Scheduling: The Critical Path Algorithm Version 1 (Part 1)

This lesson explains how to create a priority list using version 1 of the critical path algorithm. Site: http://mathispower4u.com

From playlist Scheduling

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Introduction to Scheduling

This lesson introduces the topic of scheduling and define basic scheduling vocabulary. Site: http://mathispower4u.com

From playlist Scheduling

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Scheduling: The List Processing Algorithm Part 2

This lesson explains and provides an example of the list processing algorithm to create a digraph and make a schedule. Site: http://mathispower4u.com

From playlist Scheduling

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Intro to Priority Lists & Schedules

Worked out examples involving priority lists and schedules.

From playlist Discrete Math

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Speakers: Felix Erkinger, Erwin Erkinger What the heck is realtime - and what to do with it An overview on realtime software design, with explanations of commonly used terms and methods. For more information visit: http://bit.ly/22c3_information To download the video visit: http://bit.

From playlist 22C3: Private Investigations

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Kernel Recipes 2019 - RCU in 2019

RCU has seen lots of changes in the last 2 years. Of note is the RCU flavor consolidation and tree RCU’s lock contention improvements. There have been also improvements with static checking, fixes to scheduler deadlocks and improvements to RCU-based linked lists. This talk starts with an i

From playlist Kernel Recipes 2019

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Lec 7 | MIT 6.033 Computer System Engineering, Spring 2005

Virtual Processors: Threads and Coordination View the complete course at: http://ocw.mit.edu/6-033S05 License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu

From playlist MIT 6.033 Computer System Engineering, Spring 2005

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Kernel Recipes 2015 - CPU isolation: state of the art - by Frederic Weisbecker

HPC and real time workloads want to use 100% of the CPU and need to get rid of the tiniest noise from the kernel. How much can we do that now and what remains to be done. Frédéric Weisbecker, Red Hat

From playlist Kernel Recipes 2015

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From playlist Behind the Scenes in Real-Life Software Design

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Get free resources on Modeling and Simulating Motor Controllers: http://bit.ly/2P6Lt7h Learn how you can quickly design a new motor control system using Embedded Coder® from MathWorks and the C2000™ family of microcontrollers from Texas Instruments. Introduction to Brushless DC Motor Co

From playlist Power Electronics Control Design

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Principles of Dynamic Interfaces

For the latest information, please visit: http://www.wolfram.com Speaker: Lou D'Andria Wolfram developers and colleagues discussed the latest in innovative technologies for cloud computing, interactive deployment, mobile devices, and more.

From playlist Wolfram Technology Conference 2015

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position:fixed keyboard focus jump

If you have a keyboard input element in position fixed, and are scrolled away from the very top, the fixed element moves. Live in latest iOS.

From playlist position:fixed

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For every error, I do 1 push-up

Broadcasted live on Twitch -- Watch live at https://www.twitch.tv/simuleios

From playlist Misc

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Scheduling: The Decreasing Time Algorithm

This lesson explains how to use the decreasing time algorithm to create a priority list and then a schedule. Site: http://mathispower4u.com

From playlist Scheduling

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position:fixed paints the update, but doesn't move elements

position:fixed paints the update, but doesn't move elements in iOS 5.1.1. And the fix for this bug: http://14islands.tumblr.com/post/30313367126/solved-position-fixed-scrollto-bug-ios (a work around, but simple to implement).

From playlist position:fixed

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Scheduling: The Critical Path Algorithm Version 1 (Part 2)

This lesson explains how to use version 1 of the critical path algorithm to create a priority list and then make a schedule. Site: http://mathispower4u.com

From playlist Scheduling

Related pages

Scheduling (computing)