CS 423 – Operating Systems Design
Lecture 1 - Introduction
Klara Nahrstedt
Fall 2011
CS 423 - Fall 2011
Overview
Course information (personnel, policy,
schedule, misc.)
 What is OS? What does it do?
 History of OS
 Summary

CS 423 - Fall 2011
Instructor

Klara Nahrstedt


PhD University of Pennsylvania in 1995
Research:








Multimedia distributed systems (overlay multicast, peer-to-peer
systems, service composition),
Multimedia operating systems (soft-real-time scheduling, caching),
Multimedia networking (routing, QoS management, pricing,
security),
Multimedia applications (multi-camera tele-immersive systems)
Mobile Peer-to-Peer Systems – Content Distribution
Resource Management in Wireless 802.11 Networks
Power-aware OS in mobile devices
Mobility Patterns in Mobile Learning Communities
CS 423 - Fall 2011
Overview

Office Assistants:
 Lynette Lubben (llubben@illinois.edu) for Klara
Nahrstedt

Teaching Assistants:
 Raoul Rivas (trivas@illinois.edu)
 Keun Soo Yim (yim6@illinois.edu) (Online TA)
Class Website
http://www.cs.illinois.edu/class/fa11/cs423/
Newsgroup: uiuc.class.cs423 and
uiuc.class.cs423.announce



Two newsgroups – one for discussion on machine problems,
one for announcements
CS 423 - Fall 2011
Required Readings for cs423

Required Textbook:
 Modern
Operating Systems, Andrew S. Tanenbaum,
Prentice Hall, third edition, 2008

Recommended Textbooks:
 Linux
Kernel Development, Robert Love, Safari Online
Book, 2010, 3rd edition.
 Linux Device Drivers, Corbet, Rubini, Kroah-Hartman,
O’REILLY, 2005, 3rd edition.
 Pro Android 2, Hashimi, Komatineni, MacLean, Apress,
2010.
 But mostly online resources
CS 423 - Fall 2011
Course Prerequisites

CS 241 – MUST (or similar course)
 There
will be a test similar to exams of cs241 (takehome exam – not graded – it is for your own
evaluation)


If you can finish more than 80% of the exam, you should be
fine in the class
If you cannot finish the exam with 70% and lower, then it
means that you should consider sitting in cs241 or taking it
first
 Take-home
exam will be posted on 8/26
 Solutions to take-home exam will be posted on 9/1
CS 423 - Fall 2011
Facilities and Office Hours

Laboratory Facilities
 CSIL-
linux and windows machines, 216 SC,
 Starting October 14, we will start leasing Android
phones for MP3 and MP4 assignments.



Nexus-S and Droid phones
Office hours: available in web page
For online students:
will have collaborative tool ‘elluminate’ - will be
available for online TA office hours
 Otherwise use with Instructor/TAs to communicate
 we

Skype, Email, Chat – text messaging
CS 423 - Fall 2011
Online Students
Recording links sent by email to online
students
 There will be link from class website to the
recording server for all students (protected
by password after two weeks)

CS 423 - Fall 2011
About this course…
Principles






System concepts
OS design
Algorithms
Policies
Rationale
Practice
Goals



Understand OS
decisions
Basis for future
learning
Get hands dirty
 Linux
and/or
 Android
CS 423 - Fall 2011
Expect (Some) Pain
Fast pace
Hard material
4 MPs (programming)
2 Homework
1 Midterm and 1 Final
(Comprehensive) Exam
But….
Students survived past cs423!
CS 423 - Fall 2011
Source:
http://en.wikipedia.org/wiki/Ben_Bernanke
Grading




Final exam: 35%
Mid-exam: 20%
2 Homework: 10%
4 MPs: 35%

1st MP – not graded

but absolutely essential to do – practice to work with the Linux
MP – 11% - major Linux scheduling problem
 3rd MP – 11% - resource management problem
(power, file system, memory …)
 2nd

 4th

Two options: Linux or Android
MP – 13% - distributed load management
Two options: Linux or Android
CS 423 - Fall 2011
Grading policy
Gradebook system: http://compass.uiuc.edu
 Late policy for MPs and Homework
Assignments

 No
Late Policy, but there will be 3 Bonus Days
(can’t take all three bonus days for one MP!)

It is your responsibility!
 Check
announcements in lectures, newsgroups,
or web pages
MPs will be done in Groups of 2-3 students
 MPs done on vmware server

CS 423 - Fall 2011
Group Setup

Setup Groups between 8/22 and 8/24






By evening of 8/24, you should setup groups on
compass.illinois.edu (under cs423 Fall 2011 class) by filling
out the form under “MP Sign up”
If there are any issues, email to the TA (Raoul Rivas trivas@illinois.edu)
Specify name of the group members and netid of group members
David Andersen (system admin) will setup accounts on
the vmware server.
Between 8/27 and 29 the TA will inform each group their
login and password to start to work on the vmware server
The instructions about working on the vmware server will
be also posted on class web and compass.
CS 423 - Fall 2011
Re-grading policy
Students have 1 week (after the grade for
a Homework/MP/exam is released into
compass gradebook) to request for regrading
 Re-grading requests need to be in writing
to the TAs
 After the re-grading period, no re-grading
request will be granted for this
Homework/MP/exam.

CS 423 - Fall 2011
Cheating Policy
Academic integrity
https://wiki.engr.illinois.edu/display/undergradProg/H
onor+Code
Your homework and exams must be your own - we
have a zero tolerance policy towards cheating of any
kind.






FIRST OFFENSE – 0 points on any homework, exam, MP,
SECOND OFFENSE - F - failing grade in the course.
Both the cheater and the student who aided the
cheater will be held responsible for the cheating
Machine problems will be graded per group, i.e.,
each member gets the same number of points.
CS 423 - Fall 2011
Lecture Format
Help you understand important and hard
OS concepts
 Lectures do not cover everything

 Not
all questions in homework or exams are
from lectures (read textbook)

Students responsibility
 Attend
lectures
 Read textbooks
 Homework, MP, Exam, Interviews
 Periodically check web page
 Read/utilize newsgroup
CS 423 - Fall 2011
MPs (Deadlines)
MP1, 9/9/2011 (recommended Proc File, Synchronization, warm up
– not graded)
to prepare working within Linux
kernel
MP2, Friday, 9/30 - deadline
Monday 10/3 - interviews
Kernel Process Management/
Scheduling
MP3, Friday, 11/4 – deadline
Monday 11/7 - interviews
Resource Management (Android or
Linux)
MP4, Friday, 12/2 – deadline
Monday 12/5 – interviews
Power/Time-sensitive Distributed
Load balancing - more of an open
ended assignment - Competition
for students who pick Android for
the final MP4
CS 423 - Fall 2011
Homework & Exams
10/3-10/10, 5pm
HW1
10/12, Monday,
10-10:50am
Midterm
Exam (Inclass)
HW2
11/28-12/7, 5pm
12/15, Thursday,
8-11am
Room: TBD
Final Exam
(Comprehen
sive)
CS 423 - Fall 2011
• Announcement in web
page/newsgroup/compass
• No makeup homework
• No makeup exams unless
with documented
medical emergency
¼ Unit Project: graduate students




Final grade is decided upon ¾ unit performance
¼ unit project: pass or fail
Individual or group of two
Choices
 Implementation

project, Animation project, Survey
Proposal due: 9/16, Friday, 5pm
 Write:
½ - 1 page of proposal in ascii or pdf format
 Specify: (a) scope of the problem, (b) problem
description, (c) deliverables, (d) timelines.

Email to klara@illinois.edu
 Details
in web page
CS 423 - Fall 2011
What Is an OS?
“Code” that:



Sits between programs & hardware
Sits between different programs
Sits betweens different users
But what does it do?
to provide an orderly and controlled allocation of the
processors, memories and I/O devices among the
various programs competing for them
CS 423 - Fall 2011
What Is an OS?
Resources
 Allocation
 Protection
 Reclamation
 Virtualization
Services
 Abstraction
 Simplification
 Convenience
 Standardization
Makes computers simpler
CS 423 - Fall 2011
What Is an OS?
Resources
 Allocation
 Protection
 Reclamation
 Virtualization
Finite resources
Competing demands
Examples:
 CPU
 Memory
 Disk
 Network
CS 423 - Fall 2011
What Is an OS?
Resources
 Allocation
 Protection
 Reclamation
 Virtualization
You can’t hurt me
I can’t hurt you
Implies some degree of
safety & security
CS 423 - Fall 2011
What Is an OS?
Resources
 Allocation
 Protection
 Reclamation
 Virtualization
The OS gives
The OS takes away
Voluntary at run time
Implied at termination
Involuntary
Cooperative
CS 423 - Fall 2011
What Is an OS?
Resources
 Allocation
 Protection
 Reclamation
 Virtualization
illusion of infinite,
private resources
Memory versus disk
Timeshared CPU
CS 423 - Fall 2011
History of Operating Systems
(1)

First generation 1945 – 1955
 vacuum

tubes, plug boards (no OS)
Second generation 1955 – 1965
 transistors,

Third generation 1965 – 1980
 ICs

batch systems
and multiprogramming
Fourth generation 1980 – present
–
personal computers, hand-held devices,
sensors
CS 423 - Fall 2011
History of Operating System (1945-55)
Early batch system
 bring cards to 1401
 read cards to tape
 put tape on 7094 which does computing
 put tape on 1401 which prints output
CS 423 - Fall 2011
History of Operating Systems
(1955-65)





Structure of a typical JCL job – 2nd generation
Single user
Programmer/User as the operator
Secure, but inefficient use of expensive resources
Low CPU utilization-slow mechanical I/O devices
CS 423 - Fall 2011
History of Operating Systems
(1965-80)

Multiprogramming system
–
–
–
Three jobs in memory – 3rd generation
Spooling - use disk as a very large buffer for input/output devices
Polling/Interrupts, Timesharing
CS 423 - Fall 2011
The Operating System Zoo
(1980-present)







Mainframe operating systems
Server operating systems
Multiprocessor operating systems
Personal computer operating systems
Real-time operating systems
Embedded operating systems
Smart card operating systems
CS 423 - Fall 2011
Summary
Course overview
 Policy and requirement
 What is OS?
 OS history


Next lecture: OS architectures/system
overview
CS 423 - Fall 2011
After this lecture…






Reading assignment: chapter 1.1-1.4
Browse the web site
Subscribe to newsgroup
Login to csil machines, compass, …
Setup Groups: 8/22-8/26(fill out form on
compass and submit the form)
Think about what are the criteria to
evaluate an OS?
CS 423 - Fall 2011