1

2 Distributed Systems Spring Quarter, LUMS Umar Saif

3 The Bureaucracy Not anointed by the Queen I am not a Sir!

4 The Bureaucracy Instructor: Umar Saif TAs: –Abdul Qadeer –Shafaq Malik –Farhan Tauheed –Athar Hameed

5 Why Bother? We’ll not teach you distributed systems textbooks We’ll learn to engineer realworld complex systems You’ll leave with an intuitive sense for engineering real systems

6 Modus Operandi System design is as much an art as it is science We are using an internal MIT textbook (6.033 classnotes) from Jerry Saltzer and Frans Kaashoek We’ll refer to a traditional textbook every so often

7 Grading 15% Assignments and labs 15% Quizzes 15% Paper Discussions 20% Midterm Exam 35% Final Exam (Comprehensive)

8 Class Structure 1 Section: Everyone gets the same lecture Two 60 mins Lectures (mon, wed) Three 30 mins paper-discussion sessions (fri) –You attend one paper-session each week

9 Paper Discussions Attended by ~40 students 15% grade (10 + 5) Paper discussion modeled after program committee meetings Each Paper presented by 4 students –Motivator (context of work) –Presenter –Advocate –Devil’s advocate –Class discussion and vote

10 Papers Eric A. Brewer. Lessons from Giant-Scale Services. IEEE Internet Computing, 5(4): pp A. D. Birrell and B. J. Nelson. Implementing remote procedure calls. ACM Transactions on Computer Systems 2(1):39-59, February 1984 P.V. Mockapetris and K.J. Dunlap. Development of the Domain Name System. Proceedings of ACM SIGCOMM 1988

11 Papers Leslie Lamport. Time, Clocks, and the Ordering of Events in a Distributed System. Communications of the ACM, 21(7): , July 1978 Yasushi Saito, Brian Bershad, and Henry Levy. Manageability, Availability and Performance in Porcupine: A Highly Scalable Cluster-Based Mail Service. Proc. of the 17th ACM Symp. on Operating Systems Principles, December 1999 D. B. Terry, et al. Managing Update Conflicts in Bayou, a Weakly Connected Replicated Storage System. Proceedings of the Fifteenth ACM Symposium on Operating Systems Principles, 1995 John Ousterhout. The Role of Distributed State. CMU Computer Science: A 25th Anniversary Commemorative, ACM Press Anthology Series, R. Rashid (Ed.), July 1991

12 Papers George Candea et al. Microreboot -- A Technique for Cheap Recovery. Proc. 6th Symposium on Operating Systems Design and Implementation (OSDI), San Francisco, CA, December 2004 Stuart Staniford, Vern Paxson, and Nicholas Weaver. How to Own the Internet in Your Spare Time. Proceedings of the 2002 USENIX Security Symposium, San Francisco, CA, August Butler W. Lampson. Hints for computer system design. Proceedings of the Ninth ACM Symposium on Operating Systems Principles (SOSP).

13 Assignments Assignments: –One big project Teams of 5 –Network File System Both paper design and implementation Communication Naming Storage: Multiple users Reliability

14 What we’ll learn Principles of computer system design –Stable Performance –Correctness –High Availability –Global Scalability –Security System tradeoffs

15 Background Operating Systems Fundamentals Hardware multiplexing “Common Services” Communication + Naming –Abstractions IPC, Delegation, Protection