CHAPTER 4
Process Management

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Contents
• Process scheduling
• Process synchronization
• Deadlock
2
Chapter 4 Process Management

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Chapter 4 Process Management

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Proces Scheduling
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-Job Scheduler
-CPU Scheduler
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Chapter 4 Process Management

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Process Scheduling
Job Scheduler and CPU Scheduler
Job Scheduler ËÃ×Í Long-term Scheduler
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CPU Scheduler ËÃ×Í Short-term Scheduler
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ä»·íҧҹ㹠CPU
FCFS
SJF
PS
RR
MQS
Chapter 4 Process Management

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Process Scheduling
Job Scheduler and CPU Scheduler
Job Scheduler
CPU Scheduler
Hard disk
6
Chapter 4 Process Management

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Process Scheduling
CPU Scheduler
㪌§Ò¹ CPU ãËŒÁÒ¡·ÕèÊØ´
ÁÕ»ÃÔÁÒ³§Ò¹
(Throughput) ÁÒ¡·ÕèÊØ´
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ÁÕàÇÅҤúǧ§Ò¹¹ŒÍ·ÕèÊØ´
CPU Scheduler
(Turnaround Time)
ÁÕàÇÅҵͺʹͧ (response
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ÁÕàÇÅÒÃÍ (waiting time)¹ŒÍ·ÕèÊØ´
time) ¹ŒÍ·ÕèÊØ´
Chapter 4 Process Management

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Proces Scheduling
CPU Scheduler
FCFS
First-Come, First-Served Scheduling ¤×Í
¡ÒÃàÅ×Í¡â´Ââ»Ãà«Ê·ÕèࢌÒÁÒ¡‹Í¹·íÒ§Ò¹¡‹Í¹ ࢌÒ
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FCFS ໚¹ÇÔ¸Õ¡Ò÷íҧҹẺ non-preemptive
process ¤×Í àÁ×èÍࢌÒä»·íҧҹ㹠CPU áŌǨÐäÁ‹
ÊÒÁÒö¤×¹ CPU ãËŒ¡Ñºâ»Ãà«ÊÍ×è¹ä´Œ
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Chapter 4 Process Management

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Proces Scheduling
CPU Scheduler
FCFS
T = ∑ni=1
9
Chapter 4 Process Management

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Proces Scheduling
CPU Scheduler
SJF
PROCESS
TIME
P1
24
P2
3
P3
3
Shortest-Job-First Scheduling ¤×Í ¡ÒÃ
àÅ×Í¡â´Ââ»Ãà«Ê·Õè㪌àÇÅÒ¹ŒÍ·ÕèÊØ´ä´Œ·íÒ§Ò¹¡‹Í¹
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à¾×èÍÅ´ waiting time ãËŒ¹ŒÍÂŧ áÅÐà¾×èÍ
á¡Œ»˜ÞËÒ convoy effect
Chapter 4 Process Management

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Document Outline

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