COMS 4118: Operating Systems I (Spring 2007)

Resources Syllabus Assignments


Design and implementation of operating systems. Topics include process synchronization and interprocess communication, memory management, virtual memory, interrupt handling, processor scheduling, device management, I/O, and file systems. Hands-on study of Linux operating system design and kernel internals. Science requirement: partial fulfillment.

Series of lectures, combined with homework assignments that are primarily focused on programming. Students will gain hands-on experience and will apply the concepts that are presented and explained in the lectures.


CSEE W3827 (Computer Architecture) and thorough knowledge of C and programming tools as covered in W3157 or W3101. COMS 3137/3139 (Data Structures) recommended.


Tuesdays and Thursdays, 9.10 am to 10.25 am, 535 Mudd.

Instructional Staff

Prof. Henning Schulzrinne (office hours: Tuesdays, 4-5 pm or by appointment with Rosemary Addarich), contact at
Teaching assistant:
Zhiyang Cao (office hours: Wednesdays, 3-5 pm or by appointment)
Mansoor A. Alicherry (office hours: Fridays, 10 am - 12 noon, CSB 509, or by appointment)
Albert Tsai (office hours: Monday, 10 am - 12 noon, Mudd 122A, or by appointment)


The following books are required:

The following books are optional:

E-books contains a number of on-line books related to operating systems.

Class Mailing Lists and Other Resources

Computing Requirements

$50 CS account fee required, which will provide on-campus access to x86 PC running Redhat Linux, GNU C development environment, and VMware Workstation 4.5.2 for Linux. CVN students should have at least SSH access to these facilities. A Linux 2.6.8 kernel will be used for assignments. All programs will use C, although Java will be used for some of the examples and parts of the text book.

All programming can be done on any machine that can run Linux, gcc and VMware. However, only those programs which compile using the gcc compiler on the CLIC machines will be graded. Furthermore, it is critically important that all submitted program listings and executions be thoroughly documented. Poorly documented programs will be penalized.

All programs must compile and all kernels you modify must also boot; programs and kernels that do not compile and boot will receive a grade of zero. Usually the homework assignments will only state the major objectives of the program to be written; it will be often up to you to make design decisions about things like I/O, efficiency, error handling, and so on. Make sure you provide adequate test cases to indicate the correctness and robustness of your approaches.

Grading and Late Policies

50%: Homework Assignments:
There will be approximately twelve homework assignments, assigned roughly every week and alternating between larger programming projects and question-based assignments. The programming problems will involve building a shell and kernel-level programming in the Linux operating system.
20%: Midterm:
The midterm is one class period, closed book, calculator permitted. The midterm will cover all material discussed in the course up to the week before the exam.
30%: Final:
The final exam is scheduled at the normal final exam time for this class period. The final is closed book, calculator permitted. The final is cumulative and will cover all material discussed in the course.
0%: No "extra credit" work

Programming assignments are done in groups of three, initially assigned at random. After each assignment, any students rated low in participation in the group will be combined with other such students in those groups. Thus, group memberships may change. All students within a group will receive the same score.

All homeworks are due by the date specified in the assignment (usually two or three weeks after they are issued), at NOON. The deadline for CVN students is the same as for in-class students. Homework submissions will be electronic, through CourseWorks. Complete instructions will be given with each homework.

You can submit your assignment multiple times, but the last submission is what counts. Each submission will be time stamped. Proper submission is your responsibility; we strongly urge you to make sure you understand the submission process and submit early. You can always submit again up until the deadline, so we strongly urge you to submit well before the deadline and then submit again if you have a more updated assignment to submit later.

You are allowed a total of 5 late days, to be used as you wish throughout the semester. That means you can be five days late for Homework 2 (for example), or one day late for each of the first five homework assignments, with no point penalty. Once you have exhausted your five late days, late homeworks will not be graded at all --- no extensions will be given, except for medical emergencies certified by University Health Services or a family emergency. Naturally, you may hand in incomplete assignments for partial credit by the deadline.

Also see the Columbia Policies and Procedures Regarding Academic Honesty.

We encourage you to help one another in understanding the concepts, algorithms, or approaches needed to do the homework assignments for this class. However, what you turn in must be your own, or for group projects, your group's own work. Copying other people's code, solution sets, or from any other sources is strictly prohibited. Students in previous years have often been caught cheating by copying answers from the web, which turn out to be incorrect. The homework assignments must be the work of the students turning them in. Anyone found violating the class collaboration policy will be punished severely.

All students or groups whose assignments are determined to be obviously very similar will receive a zero on the respective homework assignment for the first offense, and will receive an F for the course for the second offense ("all" means both the copy-er and copy-ee). More serious cases of cheating, such as copying someone's work without their knowledge or cheating on exams, will result in the person cheating receiving an F. In addition, offenses will be reported to the Dean's office, which may result in further disciplinary action, including suspension or expulsion from the program. Penalties will be given without discussion or warning; the first notice you receive may be a letter from the Dean. Note that you are responsible for not leaving copies of your assignments lying around and for protecting your files accordingly.


We would like the course to run smoothly and we'd like you to enjoy the course. Feel free to let us know what you find good and interesting about the course. Let us know sooner about the reverse. See us during office hours, leave us a note, or send us email.



This course builds on and borrows from the earlier Operating Systems courses taught by Prof. Nieh, Prof. Bellovin and Prof. Keromytis.