CS Fall 2011 CS 423 – Operating Systems Design Lecture 1 - Introduction Klara Nahrstedt Fall 2011

CS Fall 2011 Overview Course information (personnel, policy, schedule, misc.) What is OS? What does it do? History of OS Summary

CS 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 Networks Power-aware OS in mobile devices Mobility Patterns in Mobile Learning Communities

CS Fall 2011 Overview Office Assistants:  Lynette Lubben for Klara Nahrstedt Teaching Assistants:  Raoul Rivas  Keun Soo Yim (Online Class Website Newsgroup: uiuc.class.cs423 and uiuc.class.cs423.announce  Two newsgroups – one for discussion on machine problems, one for announcements

CS 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, 3 rd edition.  Linux Device Drivers, Corbet, Rubini, Kroah-Hartman, O’REILLY, 2005, 3 rd edition.  Pro Android 2, Hashimi, Komatineni, MacLean, Apress,  But mostly online resources

CS Fall 2011 Course Prerequisites CS 241 – MUST (or similar course)  There will be a test similar to exams of cs241 (take- home 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 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:  we will have collaborative tool ‘elluminate’ - will be available for online TA office hours  Otherwise use with Instructor/TAs to communicate Skype, , Chat – text messaging

Online Students Recording links sent by to online students There will be link from class website to the recording server for all students (protected by password after two weeks) CS 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 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! Source:

CS Fall 2011 Grading Final exam: 35% Mid-exam: 20% 2 Homework: 10% 4 MPs: 35%  1 st MP – not graded but absolutely essential to do – practice to work with the Linux  2 nd MP – 11% - major Linux scheduling problem  3 rd MP – 11% - resource management problem (power, file system, memory …) Two options: Linux or Android  4 th MP – 13% - distributed load management Two options: Linux or Android

CS Fall 2011 Grading policy Gradebook system: 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 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, to the TA (Raoul Rivas -  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 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 re- grading 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 Fall 2011 Cheating Policy Academic integrity onor+Code Your homework and exams must be your own - we have a zero tolerance policy towards cheating of any kind. onor+Code  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 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 Fall 2011 MPs (Deadlines) MP1, 9/9/2011 (recommended – not graded) Proc File, Synchronization, warm up 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 Fall 2011 Homework & Exams Announcement in web page/newsgroup/compass No makeup homework No makeup exams unless with documented medical emergency 10/3-10/10, 5pmHW1 10/12, Monday, 10-10:50am Midterm Exam (In- class) 11/28-12/7, 5pmHW2 12/15, Thursday, 8-11am Room: TBD Final Exam (Comprehen sive)

CS Fall 2011 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. to  Details in web page

CS 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 Fall 2011 What Is an OS? Resources Allocation Protection Reclamation Virtualization Services Abstraction Simplification Convenience Standardization Makes computers simpler

CS Fall 2011 What Is an OS? Resources Allocation Protection Reclamation Virtualization Finite resources Competing demands Examples: CPU Memory Disk Network

CS 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 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 Fall 2011 What Is an OS? Resources Allocation Protection Reclamation Virtualization illusion of infinite, private resources Memory versus disk Timeshared CPU

CS Fall 2011 History of Operating Systems (1) First generation 1945 – 1955  vacuum tubes, plug boards (no OS) Second generation 1955 – 1965  transistors, batch systems Third generation 1965 – 1980  ICs and multiprogramming Fourth generation 1980 – present – personal computers, hand-held devices, sensors

CS Fall 2011 History of Operating System ( ) 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 Fall 2011 History of Operating Systems ( ) Structure of a typical JCL job – 2 nd generation Single user Programmer/User as the operator Secure, but inefficient use of expensive resources Low CPU utilization-slow mechanical I/O devices

CS Fall 2011 History of Operating Systems ( ) Multiprogramming system – Three jobs in memory – 3 rd generation – Spooling - use disk as a very large buffer for input/output devices – Polling/Interrupts, Timesharing

CS 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 Fall 2011 Summary Course overview Policy and requirement What is OS? OS history Next lecture: OS architectures/system overview

CS Fall 2011 After this lecture… Reading assignment: chapter 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?