CS423 UG Operating Systems [ Undergraduate Section]

1. CS423UG Operating Systems CS423 UG Operating Systems[Undergraduate Section] Indranil Gupta (Indy) Lecture 1 Aug 24, 2005

2. Today’s Agenda • Basic Course information. • What is an OS? What does it do? • A Brief History of OS’s. • Course policy, schedule, etc. • 423UG vs. 423G (grad): different sections this semester • If you are a graduate student, you do not belong here but in the other 423 (Grad) – 1310 DCL • 423UG vs. 241: old curriculum vs. new curriculum CS 423UG - Operating Systems, Indranil Gupta

3. Who am I? • Not Jackie Chan • I am Indranil Gupta, Assistant Prof. of CS • You may call me “Indy” • no relation to the fictional Dr. Jones • PhD 2003 – Cornell University • Research: peer-to-peer systems, sensor networks, nature-inspired distributed systems • Why? Useful, Interesting, Controversial CS 423UG - Operating Systems, Indranil Gupta

4. Teaching Assistants: Brian Davis (bgdavis@) Jintae Kim (kim28@) Office Assistant: Bethany Britton (bbritton@cs.uiuc.edu) May change Required Textbook: Modern Operating Systems, Andrew Tanenbaum, 2nd edition, Prentice Happ, 2001 Class Website http://www.cs.uiuc.edu/class/fa05/cs423ug/ Newsgroup: class.cs423ug Overview CS 423UG - Operating Systems, Indranil Gupta

5. Course Information • Prerequisites • CS225; CS232 or ECE291 • Laboratory Facilities • CSIL-suna cluster • Office hours: available on web page • Indy: MF, after class (3112 SC) • Brian: 11-12 T, 2-3 W (1115 SC) • Jintae: 9-10 TR (1115 SC) • 24 hour turnaround for email and newsgroups • More info. at the end of today’s lecture… CS 423UG - Operating Systems, Indranil Gupta

6. Why are you here? • To fulfill a requirement • To satisfy a prerequisite for other courses • Networking • Distributed systems • Real-time systems • Multimedia systems • As another step in your future plans • CS Graduate schools • Industry Employment • You don’t know (that’s ok; CS is best learnt that way) CS 423UG - Operating Systems, Indranil Gupta

7. Principles System concepts OS design Some theory Rationale Practice Goals Understand OS design decisions Basis for future learning Get hands dirty About this course… CS 423UG - Operating Systems, Indranil Gupta

8. Fast pace Hard material ~4 MPs (programming) ~5 homeworks AND surprise quizzes But…. This knowledge is building block for your future plans Students have survived (and enjoyed) previous CS 423’s! Pain=Reward CS 423UG - Operating Systems, Indranil Gupta

9. Name some OS’s CS 423UG - Operating Systems, Indranil Gupta

10. Linux Unix Windows Multics BSDUnix Mac/Tiger Vista PalmOS TinyOS WinCE Spring 2K …. Name some OS’s CS 423UG - Operating Systems, Indranil Gupta

11. “Code” that: Sits between programs & hardware Sits between different programs Sits betweens different users But what does it do? Provides an orderly and controlled allocation of the processors, memories and I/O devices among the various programs competing for them Loose analogy: Government: creates and enforces laws that govern resources (money, land, houses, vehicles, oil, etc.) but allows citizens to have freedom with using the resources (as long as the citizen obeys laws) What Is an OS? What happens if two applications simultaneously use the printer? CS 423UG - Operating Systems, Indranil Gupta

12. Resources Allocation Protection Reclamation Virtualization Services Abstraction Simplification Convenience Standardization What Is an OS? $ more pictures pictures: no such file or directory Makes computers simpler (to manage, use, and understand) CS 423UG - Operating Systems, Indranil Gupta

13. Resources Allocation Protection Reclamation Virtualization Finite resources Competing demands Examples: CPU Memory Disk Network What Is an OS? Government Limited budget,Land,Oil,Gas, Printer problem: buffer! (Time Multiplexing) Space Multiplexing: give CPU to one application, disk to another application CS 423UG - Operating Systems, Indranil Gupta

14. Resources Allocation Protection Reclamation Virtualization You can’t hurt me I can’t hurt you Implies some degree of safety & security What Is an OS? Government Law and order CS 423UG - Operating Systems, Indranil Gupta

15. Resources Allocation Protection Reclamation Virtualization The OS gives The OS takes away Voluntary at run time Implied at termination Involuntary Cooperative What Is an OS? Government Income Tax CS 423UG - Operating Systems, Indranil Gupta

16. Resources Allocation Protection Reclamation Virtualization illusion of infinite, private resources Memory versus disk Timeshared CPU More extreme cases possible (& exist) What Is an OS? Government Social security CS 423UG - Operating Systems, Indranil Gupta

17. History of Operating Systems • First generation 1945 – 1955 (Anarchy) • vacuum tubes, plug boards (no OS, signup sheets or punch cards) • Second generation 1955 – 1965 (Monarchy) • transistors, batch systems • Third generation 1965 – 1980 (Feudalism) • ICs and multiprogramming • Fourth generation 1980 – present (Capitalism or Communism) • personal computers CS 423UG - Operating Systems, Indranil Gupta

18. History of Operating Systems (Monarchy) Early batch system • bring cards (multiple jobs) to 1401 • read cards to tape • put tape on 7094 which does computing • put tape on 1401 which prints output CS 423UG - Operating Systems, Indranil Gupta

19. History of Operating Systems (Monarchy) • 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 423UG - Operating Systems, Indranil Gupta

20. History of Operating Systems (Feudalism) 50’s 60’s 7094 1401 • Multiprogramming system • Multiple jobs in memory – 3rd generation • SPOOLing - use disk as large buffer for input/output devices • SPOOL=Simultaneous Peripheral Operation On-Line • Timesharing=multiple users logged on, e.g., CTSS, MULTICS IBM 360 CS 423UG - Operating Systems, Indranil Gupta

21. The Operating System Zoo (Capitalism or Communism) • 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 423UG - Operating Systems, Indranil Gupta

22. Historical Comparison CS 423UG - Operating Systems, Indranil Gupta

23. Next • Course overview – grading, MP’s, homeworks, exams. • Course Policies • Less Exciting, but Important so please pay attention • All this information is on the Grading Policies page on the CS423UG website: • http://www.cs.uiuc.edu/class/fa05/cs423ug/gradingPolicy.html CS 423UG - Operating Systems, Indranil Gupta

24. Lecture Format • Help you understand important and hard OS concepts • You need to read the relevant textbook sections before lecture • Exam, quiz and HW questions could be from anywhere in the textbook sections covered • Your best strategy is to play it safe – read all material referred to in lecture. • Make sure you also • Periodically check web page • Read/utilize newsgroup CS 423UG - Operating Systems, Indranil Gupta

25. Grading • Final exam: 30% • Mid-exam: 15% • Homeworks and Surprise Quizzes: 25% • MPs: 30% • Final grade: graded on curve. Mean/deviation/high-low scores/gaps will all be taken into account • Mean corresponding to B or B+ (depending on class performance) CS 423UG - Operating Systems, Indranil Gupta

26. Re-grading policy • Students have 1 week (after the grade for a quiz/MP/exam is released into gradebook) to request for re-grading • Re-grading requests need to be in writing and submitted after lecture or during office hours • After the re-grading period, no re-grading request will be granted for this quiz/MP/exam. CS 423UG - Operating Systems, Indranil Gupta

27. Surprise Quizzes • There will be surprise quizzes, given at the start of a lecture, during any lecture. The total number of quizzes could be anywhere between 3 and 40. • NO LATE or MAKEUP SURPRISE QUIZZES, under any circumstances whatsoever. • Surprise quizzes are completely individual efforts. • Your best strategy is to play it safe – attend every lecture. CS 423UG - Operating Systems, Indranil Gupta

28. Homeworks and MPs • HW solutions need to be typed up, with the exception that figures and tables may be drawn by hand.We will not accept hand-written solutions. You may use your favorite word processor -- Word, latex, or any other. • HWs are completely individual efforts. • If two written solutions are the same or similar, both will be penalized (100% penalty for the entire HW), or given a failing course grade (discretion).  • If a written solution is similar or same as an online or other solution resource, you will be penalized (100% penalty for the entire HW), or given a failing course grade (discretion). • Any violation of the above policies will be penalized (100% penalty for the entire HW), or given a failing course grade (discretion). • MPs are efforts done in groups of 2.  • Although you are allowed to discuss HWs/MPs with your fellow students (even outside your group), you are expected to solve them within your group (individually for HW) and write/program the solution within your group (individually for HW). You cannot use any resources beyond the textbook and online Nachos resources. Use of any readily available solutions is prohibited. • Play it safe – don’t cheat. CS 423UG - Operating Systems, Indranil Gupta

29. Cheating Policy • Academic integrity • Zero tolerance Policy towards Cheating: Your work in this class must be your own - we have a zero tolerance policy towards cheating of any kind and any student who cheats will get a failing grade in the course. • Both the cheater and the student who aided the cheater will be held responsible for the cheating CS 423UG - Operating Systems, Indranil Gupta

30. Grading policy for HW’s and MP’s • Gradebook system details posted on web soon • Late policy for HWs and MPs (only) • 6 hour extension: 10% penalty • 12 hour extension: 25% penalty • 24 hour extension: 50% penalty • 24+ hour extension: 100% penalty • No late quizzes or exams! • Sticking to dates is your responsibility! • Check announcements in lectures, newsgroups, or web pages • Your best strategy is to play it safe – submit everything on time. CS 423UG - Operating Systems, Indranil Gupta

31. Playing it Safe in CS423UG If you follow these 4 simple rules during the CS423UG class, you'll make sure that you do well in the course: • Attend every lecture. • Read the course material (textbook sections assigned+slides). • Submit everything (MPs, HWs, quizzes, exams) on time - don't be late. • Don't cheat. More details on http://www.cs.uiuc.edu/class/fa05/cs423ug/gradingPolicy.html CS 423UG - Operating Systems, Indranil Gupta

32. MPs and HWs • MPs every 2-3 weeks • MP groups of 2 students (could do individually) • MP releases and tutorial date will be announced on course web page • MP’s use C++ and Nachos. Tutorials on • C++: Tue Aug 30 (7 pm – 8 pm) and Wed Aug 31 (7 pm – 8 pm) – need to attend one only. 1404 SC. • Nachos: Tue Aug 30 (8 pm – 9 pm) and Wed Aug 31 (8 pm – 9 pm) – need to attend one only. 1404 SC. • These tutorials are optional, but you are advised to take advantage of them CS 423UG - Operating Systems, Indranil Gupta

33. Exams (Tentative Dates) • Announcements on web page • No makeup exams unless with documented medical emergency • All makeup requests to Indy at least 2 weeks prior to exam date CS 423UG - Operating Systems, Indranil Gupta

34. We’re done for now, but Todo’s for you after this lecture… • Next lecture: OS Overview (chapter 1) • Reading for today’s lecture: 1.0-1.3 • Reading for Friday’s lecture: Sections 1.4-1.6 • For next week: Chapter 2 • Browse the web site • Subscribe newsgroup • Select tutorial for C++ and Nachos • What are the jobs of an OS (or what are the jobs of a government, at least an ideal one?) CS 423UG - Operating Systems, Indranil Gupta