Scheduling

Operating Systems 3. Scheduling

Ludovic Apvrille

Telecommunications ParisTech Eurecom, Office 470 ludovic. [email protected] fr

Show up 2012

Basics of Booking Scheduling methods Scheduling in Windows and Linux

Definitions Switching Between Processes

Summarize

Basics of Scheduling Definitions Switching Between Processes Scheduling algorithms Organizing in House windows and Cpanel

Ludovic Apvrille

Operating Systems -- III. Booking - Fall season 2012

a couple of / thirty-three

Basics of Scheduling Booking algorithms Arranging in Windows and Cpanel

Definitions Moving over Between Processes

Scheduling Conditions

All devices

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Fairness: Offering each procedure a fair reveal of the CPU Policy adjustment: No method should be able to defeat the rules of the system Stability: Keeping all parts of the program busy

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Batch systems

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CPU use: Keep the CPU busy Throughput: Maximize the amount of jobs that are completed every time unit (hour) Turnaround Time: Minimize time between submission and termination Ludovic Apvrille Systems - 3. Scheduling - Fall 2012 3 / 33

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Basics of Scheduling Organizing algorithms Organizing in Windows and Linux

Definitions Turning Between Techniques

Scheduling Standards (Cont. )

Interactive devices

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Response time: Respond to interactions as fast as possible Proportionality: Meet users' expectations

Current systems

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Appointment deadlines: Keep the CPU occupied Predictability: Find out in advance whether time restrictions can often be met, or perhaps not.

Ludovic Apvrille

Systems - 3. Scheduling -- Fall 2012

4 as well as 33

Principles of Booking Scheduling algorithms Scheduling in Windows and Linux

Definitions Switching Between Processes

If you should Schedule

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At creation of a procedure

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Operate parent or child?

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By termination of your process Every time a process hindrances on I/O, semaphore, etc . When I/O interrupt happens At hardware clock disrupt ◮

Non-preemptive scheduling

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A similar process has the CENTRAL PROCESSING UNIT until it blocks or voluntarily releases the CPU Just choice if no timer is available Home windows 3. one particular The same method can operate only for a pre-defined time-interval The OPERATING SYSTEM sets a timer towards the time-interval Ludovic Apvrille Systems - III. Scheduling - Fall 2012 5 / 33

Preemptive scheduling

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Basics of Scheduling Scheduling methods Scheduling in Windows and Linux

Definitions Switching Among Processes

Non-Preemptive Scheduler

Ludovic Apvrille

Systems - III. Scheduling - Fall 2012

6 as well as 33

Fundamentals of Arranging Scheduling algorithms Scheduling in Windows and Linux

Definitions Switching Among Processes

Preemptive Scheduler

Ludovic Apvrille

Systems - III. Scheduling - Fall 2012

7 as well as 33

Fundamentals of Booking Scheduling algorithms Scheduling in Windows and Linux

Definitions Switching Between Processes

Booking Implementation

Ludovic Apvrille

Systems - 3. Scheduling - Fall 2012

8 as well as 33

Basics of Booking Scheduling algorithms Scheduling in Windows and Linux

Group systems Active systems Multiprocessor systems

Summarize

Basics of Scheduling Arranging algorithms Set systems Active systems Multiprocessor systems Organizing in Windows and Cpanel

Ludovic Apvrille

Operating Systems -- III. Scheduling - Fall 2012

being unfaithful / thirty-three

Basics of Scheduling Arranging algorithms Booking in Home windows and Cpanel

Batch systems Interactive systems Multiprocessor systems

Presented Arranging Algorithms

Pertaining to batch devices

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Pertaining to interactive systems

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First-Come First-Served Shortest Task First Shortest Remaining Time Next Three-level scheduling

Round-Robin scheduling Concern scheduling Multiple queues Assured scheduling Lotto scheduling Fair-share scheduling

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For multiprocessors systems

Presentation of 3 different techniques

Ludovic Apvrille

For RT systems

Go to lectures upon RTOS to...