Handout TIF204 Chapter 6 Process Scheduling 2016

An O verview

Operating System:
Abraham Silberschatz, Peter Baer Galvin, Greg Gagne, Oper a ting System
Concepts Essentia ls , 2012, 2th Edition, John Wiley & Sons. Inc.

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Chapter 6 Part Two: Proces s Scheduling |

CPU scheduling is the basis of multiprogrammed operating
systems. By switching the CPU among processes, the operating
system can make the computer more productive.
This chapter, we introduce basic CPU-scheduling concepts and
present several CPU-scheduling algorithms.We also consider the
problem of selecting an algorithm for a particular system.

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Chapter 6 Part Two: Proces s Scheduling |

Ch. 6: Process Scheduling

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Ch. 6: Process Scheduling

Chapter Objectives.

Age nda.

• Basic Concept
• Scheduling Criteria
• Scheduling Algorithms

• To introduce CPU scheduling, which is the basis for multiprogrammed
operating systems.
• To describe various CPU-scheduling algorithms.
• To discuss evaluation criteria for selecting a CPU-scheduling algorithm for
a particular system.
• To examine the scheduling algorithms of several operating systems.

Chapter 6 Part Two: Proces s Scheduling |

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Chapter 6 Part Two: Proces s Scheduling |

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Basic Concept

Scheduling Criteria

• Mengapa penjadwalan proses dibutuhkan?

• Kriteria penjadwalan berhubungan dengan algoritma penjadwalan.

– single-processing system tida k efisien;
– memaksimalkan penggunaan CPU (CPU
utilization );

– efisiensi waktu eksekusi proses.

• Setiap algoritma penjadwalan CPU memiliki properti yang
berbeda-beda.
• Pemilihan algoritma yang digunakan didasarkan pada properti
yang dimiliki oleh beragam algoritma pemjadwalan CPU.
• Dibutuhkan suatu kriteria yang digunakan untuk pemilihan
algoritma penjadwalan CPU.

• Strategi penjadwalan yang digunakan:
– nonpreemtive scheduling ; dan
– preemtive scgeduling.
Chapter 6 Part Two: Proces s Scheduling |

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Scheduling Criteria

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Sche duling Algorithms

• Kriteria penjadwalan yang dimaksud adalah sebagai berikut:
–
–
–
–
–

Chapter 6 Part Two: Proces s Scheduling |

First-Come, First-Serve (FCFS) Scheduling.

CPU utilization.
Throughput.
Turnaround time.
Waiting time.
Response time.

• Hitung rata-rata waktu tunggu setiap proses?

Chapter 6 Part Two: Proces s Scheduling |

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Chapter 6 Part Two: Proces s Scheduling |

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Scheduling Algorithms

Sche duling Algorithms

Shortest-Job-First (SJF) Scheduling.

• Hitung rata-rata waktu tunggu setiap proses?
Chapter 6 Part Two: Proces s Scheduling |

Prediction of the Length of the Next
CPU Burst.
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Chapter 6 Part Two: Proces s Scheduling |

Scheduling Algorithms

Shortest-Remaining-Job-First (SRJF) Scheduling.

Sche duling Algorithms

Priority Scheduling.

• Hitung rata-rata waktu tunggu setiap proses?
Chapter 6 Part Two: Proces s Scheduling |

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• Hitung rata-rata waktu tunggu setiap proses?
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Chapter 6 Part Two: Proces s Scheduling |

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Scheduling Algorithms

Operating System:

Round-Robin Scheduling.

Abraham Silberschatz, Peter Baer Galvin, Greg Gagne, Oper a ting System
Concepts Essentia ls , 2012, 2th Edition, John Wiley & Sons. Inc.

• Hitung rata-rata waktu tunggu setiap proses?
Chapter 6 Part Two: Proces s Scheduling |

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Chapter 6 Part Two: Proces s Scheduling |

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