Chapter 6 Part Two: Proces s Scheduling | 1 1-1
Operating System:
Abraham Silberschatz, Peter Baer Galvin, Greg Gagne, Oper a ting System
Concepts Essentia ls, 2012, 2
thEdition, John Wiley & Sons. Inc.
Chapter 6 Part Two: Proces s Scheduling | 2
An O ve rview
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.
Chapter 6 Part Two: Proces s Scheduling | 3
C h. 6: Process Scheduling
Chapter Objectives.
•
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 | 4
C h. 6: Process Scheduling
Age nda.
Chapter 6 Part Two: Proces s Scheduling | 5
Basic C oncept
•
Mengapa penjadwalan proses dibutuhkan?
–
single-processing system tida k efisien;
–
memaksimalkan penggunaan CPU (
CPU
utilization
);
–
efisiensi waktu eksekusi proses.
•
Strategi penjadwalan yang digunakan:
–
nonpreemtive scheduling
; dan
–
preemtive scgeduling
.
Chapter 6 Part Two: Proces s Scheduling | 6
Sche duling C riteria
•
Kriteria penjadwalan berhubungan dengan algoritma penjadwalan.
•
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.
Chapter 6 Part Two: Proces s Scheduling | 7
Sche duling C riteria
•
Kriteria penjadwalan yang dimaksud adalah sebagai berikut:
–
CPU utilization.
–
Throughput.
First-C ome, First-Serve (FC FS) Scheduling.
Chapter 6 Part Two: Proces s Scheduling | 9
Sche duling Algorithms
Shortest-Job-First (SJF) Scheduling.
•
Hitung rata-rata waktu tunggu setiap proses?
Chapter 6 Part Two: Proces s Scheduling | 10
Sche duling Algorithms
Prediction of the Length of the Next
CPU Burst.
Chapter 6 Part Two: Proces s Scheduling | 11
Sche duling Algorithms
Shortest-Remaining-Job-First (SRJF) Scheduling.
•
Hitung rata-rata waktu tunggu setiap proses?
Chapter 6 Part Two: Proces s Scheduling | 12
Sche duling Algorithms
Priority Scheduling.
Chapter 6 Part Two: Proces s Scheduling | 13
Sche duling Algorithms
Round-Robin Scheduling.
•
Hitung rata-rata waktu tunggu setiap proses?
Chapter 6 Part Two: Proces s Scheduling | 14 1-14
