lec07-scheduling - Lecture 7 CPU Scheduling Chapter 5...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
Silberschatz, Galvin and Gagne ©2009 Operating System Concepts – 8 th Edition, Lecture 7: CPU Scheduling Chapter 5
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
5.2 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts – 8 th Edition Schedulers Scheduler: a module in OS to execute scheduling decisions. Long-term scheduler (or job scheduler) – selects which processes should be brought into the ready queue Medium-term scheduler – selects which processes should be swapped in/out the memory Short-term scheduler (or CPU scheduler) – selects which process should be executed next and allocates CPU
Background image of page 2
5.3 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts – 8 th Edition new ready running terminated blocked admitted interrupt/yield scheduled wait for event event occurrence exit, kill When is scheduling done?
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
5.4 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts – 8 th Edition Big Picture Long CPU burst Short CPU burst Waiting for I/O CPU not needed. Process goes to blocked/waiting state. Interrupt: back from I/O operation, ready to use the CPU.
Background image of page 4
Silberschatz, Galvin and Gagne ©2009 Operating System Concepts – 8 th Edition Terminology: Preemptive vs. non-Preemptive Preemptive: A Process can be suspended and resumed Non-preemptive: A process runs until it voluntarily gives up the CPU (waiting on I/O or terminate). Most modern OSs use preemptive CPU scheduling, implemented via timer interrupts. Non-preemptive is used when suspending a process is impossible or very
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/17/2012 for the course COP 6611 taught by Professor Staff during the Spring '08 term at University of South Florida.

Page1 / 19

lec07-scheduling - Lecture 7 CPU Scheduling Chapter 5...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online