Computer Science 432
Operating Systems

Williams College
Fall 2006

Lecture 04: CPU Scheduling 1: Basics
Date: September 19, 2006

Quote of the day:

- Frank:	"What does that mean? PSPN?"
- Prof Williams:	"First, it means you have at least 20/30 vision. It also means
	Preemptive Shortest Process Next."
	- CS135, 1/9/91

Agenda

Announcements
Lab 1 due - hopefully all went well
Lecture assignment from last time
POSIX threads: back to those later
CPU scheduling
- Long-term, short-term, medium-term scheduling
- CPU burst times, process categorization
- CPU scheduling goals
- Relationship between response time and throughput
- Scheduling algorithms:
  - FCFS
  - SJF/SRTF
  - Priority
  - RR
  - Multilevel feedback queues
- Comparisons of scheduling algorithms
Discrete Event Simulation and Lab 2.

Lecture Assignment

Please look at these questions, but there is no need to turn them in. We will discuss them in class on Thursday.

SG&G 5.1, 5.5, 5.8, 5.10

Turn in short answers to these questions. Please turn in a hard copy (typeset or handwritten are OK) at the start of class, Thursday, September 21. We will discuss these questions during class, so no late submissions are accepted.

SG&G 5.4, 5.6

The readings for next time are two recent articles related to CPU scheduling: Petrou, et al., 1999, Krohn, 2003.

Computer Science 432 Operating Systems

Williams College Fall 2006

Agenda

Lecture Assignment

Computer Science 432
Operating Systems

Williams College
Fall 2006