15-440, Fall 2011: Distributed Systems

Latest Announcements

12/12: Project 2, parts 1 & 2 scores posted in Autolab: If you cannot find them in your account, the scores are in your partner's account (the Autolab team is working on fixing this).
12/11: Reminder, final exam is Monday the 12th, 1pm, Wean Hall 7500: See subject
12/4: No class Tuesday 12/6. Prof. Andersen's office hours rescheduled.: Please take this time to work on your projects and schedule project reviews with the course staff. You can find links to the signup pages from the assignments page. Also, Prof. Andersen's office hours will be held from 2-3pm on Monday, NOT in the morning.

Overview

15-440 is an introductory course in distributed systems. The emphasis will be on the techniques for creating functional, usable, and high-performance distributed systems. To make the issues more concrete, the class includes several multi-week projects requiring significant design and implementation.

The goals of this course are twofold: First, for students to gain an understanding of the principles and techniques behind the design of distributed systems, such as locking, concurrency, scheduling, and communication across the network. Second, for students to gain practical experience designing, implementing, and debugging real distributed systems.

The major themes this course will teach include scarcity, scheduling, concurrency and concurrent programming, naming, abstraction and modularity, imperfect communication and other types of failure, protection from accidental and malicious harm, optimism, and the use of instrumentation and monitoring and debugging tools in problem solving. As the creation and management of software systems is a fundamental goal of any undergraduate systems course, students will design, implement, and debug large programming projects.

Evaluation is based on homework assignments, the projects, and three exams.

Instructors: David Andersen, Randy Bryant.
Lecture time: Tues/Thurs 10:30 - 11:50, GHC 4307
Recitations: TBA
Units: 12

Learning Objectives

After this course, students will have learned to...

Implement and structure distributed systems programs;
Write programs that can interoperate using well-defined protocols
Debug highly concurrent code that spans multiple programs running on multiple cores and machines
Reason about distributed algorithms for locking, synchronizationa and concurrency, scheduling, and replication
Use standard network communication primitives such as UDP and TCP
Understand the general properties of networked communication necessary for distributed systems programming in clusters and on the Internet
Employ and create common paradigms for easing the task of distributed systems programming, such as distributed filesystems, RPC, and MapReduce. Be able to clearly elucidate their benefits, drawbacks, and limitations.
Identify the security challenges faced by distributed systems programs;
Be able to select appropriate security solutions to meet the needs of commonly encountered distributed programming scenarios.

Course Staff

Teaching Assistants

Name	Email	Office	Tel	Hours
Iulian Moraru	iulian AT cs DOT cmu DOT edu	GHC 9023	412-268-5942	Wednesdays 3:00-4:00
Ravi Starzl	rstarzl AT cs DOT cmu DOT edu	GHC 5501		Tuesdays 12:00pm-1:00pm and by appointment
TBA	staff-440 AT cs DOT cmu DOT edu

Instructors

Name	Email	Office	Tel	Hours
David Andersen	dga AT cs DOT cmu DOT edu	GHC 9109	412-268-3064	Monday 11:00 - 11:59am
Randy Bryant	bryant AT cs DOT cmu DOT edu	GHC 5113	412-268-8821	Fridays 3:00-4:00

Course Secretary

Angela Miller, amiller AT cs DOT cmu DOT edu, GHC 9118, Tel: 412-268-6645

Office Hours

Day	Time	Location
TBA	TBA	TBA

Course Policies

Collaboration

Students are encouraged to talk to each other, to the TAs, to the instructors, or to anyone else about any of the assignments. Any assistance, though, must be limited to discussion of the problem and sketching general approaches to a solution. Each student must write out his or her own solutions to the homework. The project handouts have more detailed information about collaboration when working on the projects, but, basically, each programming project group must write their own code and documentation for the programming projects done as a group.

Consulting another student's or group's solution is prohibited, and submitted solutions may not be copied from any source. These and any other form of collaboration on assignments constitute cheating. If you have any question about whether some activity would constitute cheating, please feel free to ask the instructors.

You may not supply work that you complete during 15-440 to other students in future instances of this course or for use in future instances of this course (just as you may not use work completed by students who've taken the course previously).

Late Policy

Take project and homework deadlines seriously. Our experience is that students often seriously underestimate the effort involved in programming assignments and projects. If we give you 4 weeks to complete an assignment, there is typically a reason. In the interest of fairness, we have adopted the following late policy:

Each student is given a total of 2 "free points" to use during the semester.
One free point can be used to extend the deadline of any homework assignment by a single day with no penalty.
Two free points are needed to extend the deadline of Projects I or II by a single day with no penalty (you and your partner might each contribute a point).
In the absence of free points, the deadline for any assignment can be extended with a 10% penalty per day.
No deadline can be extended by more than two days, regardless of how many free points you have saved up. Assignments will NOT be accepted 48 hours after the due date.
If you are ill: If you have a medical note, you may turn in your assignments late without using free points. Please contact the instructors to arrange a reasonable replacement turn-in time. You must notify us before the due-date. Without a medical note, you must use your free points as you would with any other reason for being late.

Re-Grading

If you think we made a mistake in grading, please return the assignment with a note explaining your concern to the course secretary no later than two weeks after the day the assignment was returned. We will have the question re-graded by the person responsible for grading that question.

Recordings

The course staff in 15-440 strongly encourage participation and asking questions during lectures (and definitely during recitations). Therefore, to protect the privacy of your fellow students, no audio or video recordings may be made of the class without the prior permission of the instructor. If the course staff make audio or video recordings of the course, we will notify the course before such recordings are made (and will make it extremely obvious because there will be a big camera in the back of the room...).

Partner Problems

Please try to avoid having partner problems. Seriously! Share your hopes before they turn into concerns, your concerns before they have problems, and your problems before they inflate into crises.

Also, in order for the course staff to help you and your partner work through issues, or for us to provide an appropriate response to serious partner problems, you must contact us well before the relevant due date! While some problems can never be truly solved, it is likely that your career after CMU will you to sometimes "involve management" to address issues with co-workers, and will certainly require you to work out all sorts of problems with your co-workers. If you find yourself in a situation which you can't resolve, it will provide you with an opportunity to practice interacting with management.

A special case to avoid is coming to us a day or two before a major deadline to tell us that your partner has been ill (etc.) for multiple weeks. We, and thus you, have many more options if you inform us while a problem is developing, instead of after the fact.

Resources

Class newsgroup: academic.cs.15-440
If you have a question about a project handout or a technical issue, there is an excellent chance that other students have the same question. Please read the newsgroup to see if there has been traffic, and consider posting your questions there.
Announcements newsgroup: academic.cs.15-440.announce
Staff mailing list: staff-440 at cs dot cmu dot edu
If you have a question you believe is particular to your circumstances and should not be posted in a public forum (e.g., one that involves posting the solution to homework problems), send mail to the staff list, which reaches the instructors and TAs. Questions of general interest sent to the staff list will probably be replied to via the newsgroup. If your question involves a confidential personal or academic-conduct issue, you should probably contact one of the instructors in person or send mail to both.
Suggested study problems - if you'd like a bit more structure to help guide your studying, we list some problems from the book that you might find helpful.