CS 395T, Fall 2010: Operating Systems Implementation

Latest Announcements

12/17: Final grades sent to registrar
12/17: Project grades posted to egradebook: We gave each project a letter grade and mapped it to a number. See the comments on egradebook for the exact mapping that we used.
12/6: Make-up rescheduled to Monday, December 6, 4:30 PM, ACES 6.302
12/2: Make-up tomorrow canceled: Please send us email if you'd like to make-up the make-up on Monday.
11/30: Prep for Thursday: In preparation for Thursday's class, please do the following: (1) Read the Hints paper. For several of the hints in the paper (your choice which hints), think through where we have seen these hints applied in systems we have read about. (2) For several of the hints in the Hints paper (again, your choice about which hints; they need not be the same as in (1)), think through where we have seen these hints NOT applied in systems we have read about. (3) For the Secure File Nets paper, please pay particular attention to the graphs.
11/24: Project demo sign-up: Don't forget to sign up for a demo slot. The instructions are posted in the lab 7 text.
11/20: Removed bogus hints page from lab 7: Those hints pertained to an old version of lab 5. Apologies for the false hints. Note, though, that if you're having trouble with lab 7, a possible source of bugs is your lab 5 code
11/15: Office hours this Friday rescheduled to next Monday: Mike's office hours will be at 4:00 PM Monday, November 22 (not 3:00 PM on Friday, November 19). As always, send email if you'd like to meet at another time.
11/4: Updates to labs 6 and 7: Please git pull the changes immediately if you have started either lab.
10/31: Lab 5 typo.: The comment at the beginning of fs/serv.c that says 'There can be at most MAXFILE files open concurrently.' should say MAXOPEN instead of MAXFILE. The repo is updated and you may 'git pull' the change if you'd like.

Course Information

Time and place: TueThu 17:00 - 18:30, PAR 310
- Make-up times: There are days when I cannot avoid being out of town. We will not meet then, and we'll make up these classes on selected Friday afternoons, 4:30-5:45 PM.
Instructor: Michael Walfish.
- Office hours: Fridays, 3:00-4:00 PM, or by appointment. Office: ACES 6.252.
Lab assistant: Victor Vu
- Office hours: Wednesdays, 3:00-4:00 PM. Location: seating area ouside ACES 6.252.
- Email address: username is diragjie. domain is cs.
Staff mailing list: cs395t-f10-staff@cs. If you have questions about the labs, please email the staff mailing list, not either of the staff members individually. The main reason to email a staff member individually is if you specifically want to meet that person and cannot make office hours.

Description

This course is for students who want to hack on operating systems and more generally learn how they work. Class meetings will cover research papers (both classic and recent) and readings on operating systems, with a significant portion of class time devoted to discussion. Time permitting, we will focus on security-related questions. A crucial component of the course is the labs. Students will implement the core of an exokernel-style operating system, called JOS. (JOS was developed for MIT's 6.828 and has been used in courses at several other schools, including UT.) Starting in fall 2010, this course counts as a diversity course in Systems (thread 1).

The work

The class will consist of assigned readings, twice-weekly discussions, labs, a midterm exam, and a final project:

The assigned readings are research papers, and they should be completed before class.
The discussions are based on the assigned readings. The policies page contains detail about the relationship between readings, discussion, and grading. The short version is: participation is an important component of your grade, but if you haven't read the paper, you should not show up for the discussion. (Seriously.) Also, the discussion will involve some cold-calling (the exact fraction is TBD). Cold-calling here means that the instructor will ask a question so everyone can think about the answer, then select a student's name using a shuffled deck of cards, and then call on that student.
The labs are a crucial component of this course. You will implement (the interesting pieces of) a real operating system that will boot on a PC. The labs are described in more detail here.
The midterm exam will cover the first two-thirds of the class. See details here.
The final project has some flexibility. The default option is for you to add a significant piece of functionality to JOS, working in pairs. However, another option is to build something that is independent of JOS. The three requirements for this second option are as follows. The project must (1) have a significant implementation component, specified by deliverables (2) concern operating systems and (3) be challenging and potentially research-worthy. As the semester goes on, we will post some project ideas in this second category. For all projects, you must write a proposal that is accepted by the course staff.

Prerequisites and suggested background

We will assume basic systems knowledge, such as an undergraduate course in operating systems, networking, or distributed systems. An alternative is significant systems-building experience on a large project.
The labs assume comfort and fluency in C programming.
The labs require some assembly programming and provide tutorials.
If you are planning to take this class, and you do not have all of fluency in C, some exposure to assembly, and systems-building experience, that is okay: you will learn these things! However, you should leave extra time to complete the labs, particularly at the beginning of the course. As a common example, if you are not comfortable with C-style pointers, then this item applies to you. (If you have never had an undergraduate course in systems, that is probably less okay, but you can always try to take this course and see how it goes.)

A note about the labs

Regardless of whether you have the suggested background, we recommend that you start the labs long before they are due. The standard advice is "Start the labs early", but that is not quite right. The best advice, I think, is "Start the labs on time, but on time is probably much earlier than you think it is".