Syllabus: Operating Systems

CS 377 Operating Systems (Fall 2012)

Course Materials

Description

This course will provide an introduction to operating system design and implementation. The operating system provides a well-known, convenient, and efficient interface between user programs and the bare hardware of the computer on which they run. The operating system is responsible for allowing resources (e.g., disks, networks, and processors) to be shared, providing common services needed by many different programs (e.g., file service, the ability to start or stop processes, and access to the printer), and protecting individual programs from one another.

The course will start with a brief historical perspective of the evolution of operating systems over the last fifty years, and then cover the major components of most operating systems. This discussion will cover the tradeoffs that can be made between performance and functionality during the design and implementation of an operating system. Particular emphasis will be given to three major OS subsystems: process management (processes, threads, CPU scheduling, synchronization, and deadlock), memory management (segmentation, paging, swapping), file systems, and operating system support for distributed systems.

Prerequisites

CMPSCI 230: Computer Systems Principles is a pre-requisite for this class. It is not advisable to take CMPSCI 230 and CMPSCI 377 in the same semester.

Major Requirements and Grading

You are expected to attend class regularly, read the assigned reading before class, and participate in class discussions. The course will be graded on a curve.

Course Policies and Other Requirements

The work of this course consists of:
  1. Attending and actively participating in class lectures and discussion section
  2. A number of homework and in-class assignments
  3. Four programming projects
  4. Three examinations, two midterms and one final

Attendance

Class lectures and discussions are an integral part of this course. Attendance at both are mandatory, although they are ungraded. Many helpful hints about the projects and exams will be made in class lecture, so it behooves you to attend.

Programming Projects: 45%

Four group projects will be assigned during the term , each of which will require a substantial time commitment on your part. Many students find the work load in this course to be heavy. The most common reason for not doing well on the projects is not starting them early enough. You will be given plenty of time to complete each project. However, if you wait until the last minute to start, you may not be able to finish. Start early and plan to have it finished a few days ahead of the due date - many unexpected problems arise during programming, especially in the debugging phase. Your lack of starting early is not an excuse for turning in your project late, even if some unfortunate situations arise such as having your computer crash. There are many sources of help on which you can draw. Most questions can be submitted to the teaching staff and your fellow classmates via electronic news. These will typically be answered within the day, often more quickly during working hours. However, some types of questions cannot be answered without seeing your project. If you have detailed questions on your program, speak to one of the teaching staff in person during office hours. Students are also encouraged to help one another on the course concepts (but not the implementation of the projects). One of the best ways for you to make sure that you understand a concept is to explain it to someone else. Keep in mind, however, that you should not expect anyone else to do any part of your project for you. The project that you turn in must be your own.

Group policies

All projects in this course are group projects. You must form a group of 2 students for these projects. To declare a group's membership, send e-mail to shenoy [at] cs.umass.edu and sbarker [at] cs.umass.edu with the group members' names and email addresses. The group declaration deadline is Sept 13 (shortly after Project 0 is assigned). After this date, we will randomly combine remaining students into groups of 2. It is in your best interests to choose your partners carefully. You should discuss topics such as prior experience, course background, goals for this course, workload and schedule for this semester, and preferred project management and work style. Make sure you can find several blocks of time during the week to meet to discuss or carry out the project. Students are expected to participate wholly in their group to the benefit of the entire group. All group members should be familiar with all aspects of the project, irrespective of their role on the project. We expect all group members to contribute their fair share, and we expect to assign the same project grade to all members of a group. Group members will evaluate the contributions of other group members after each project. Members who contribute less than their share may receive a lower grade on the project; non-contributing members will receive a zero. In case of disputes regarding contribution, one of the teaching staff may interview group members on the project design and implementation.

Students may be fired from a group by the majority vote of the remaining members. The procedure for this is as follows: (1) documented gentle warning risk of firing in e-mail, with cc to all group members and to shenoy [at] cs.umass.edu, with cause and specific work required to remain in group; (2) allow at least 72 hours for compliance; (3) send documented statement of firing in e-mail, with cc to all group members and to shenoy [at] cs.umass.edu. Fired group members must actively pursue and obtain membership in another group. Students that don't get hired or cannot find partners will need to work alone. So, it is in your interest not to get fired by your group. Managing group dynamics and using each group member's time and talents effectively can be as difficult as solving the project. We are happy to offer advice on how to handle these issues. Be open and candid with your group about any potential problems early on so that your group can plan around such problems and not fall behind. A sure way to make your group upset at you is not finishing your part of the work at an agreed-upon deadline and not informing them about the problems early enough for them to help.

Turning in projects

Projects will be submitted electronically. Projects are due at 5:00 pm on the due date. To account for short-term unexpected events like computer crashes, submission problems, and clock skew, we will allow 4 hours of slack and accept projects until exactly 8:59 pm.

Sometimes unexpected events make it difficult to get a project in on time. For this reason, each group will have a total of 3 free late days to be used for projects throughout the semester. These late days should only be used to deal with unexpected problems such as illness. They should not be used simply to start later on a project or because you are having difficulty completing the project. Projects received after the due date (assuming that you have no late days left) will receive a zero, even if it is just one second late. Try to save some late days for the last project. Weekend days are counted in the same way as weekdays (e.g. if the project deadline is Friday and you turn it in Sunday, that's two days late).

Extensions

Extension requests (other than the use of free late days) should be made before the original due date. Extensions will only be granted for medical or personal emergencies. All extension requests must be accompanied by written verification, for example a written note from your doctor. In most cases, your project group members will be expected to make up the deficit without needing an extension. Extensions are not granted for reasons such as: you erased all your files, the lab was crowded and you couldn't get a computer, you had other course work or job commitments which interfered, etc.. You can avoid all these problems by starting the projects early and keeping backup files. If you are having trouble understanding the material or designing a program, please come to office hours for help right away.

Doing your own project

All projects in this course are to be done by your own group. Violation will result in a zero on the project in question and initiation of the formal procedures of the University. We use an automated program and manual checks to correlate projects with each other and with prior solutions. At the same time, we encourage students to help each other learn the course material. As in most courses, there is a boundary separating these two situations. You may give or receive help on any of the concepts covered in lecture or discussion and on the specifics of Java syntax. You are allowed to consult with other students in the current class to help you understand the project specification (i.e. the problem definition). However, you may not collaborate in any way when constructing your solution -- the solution to the project must be generated by your group working alone. You are not allowed to work out the programming details of the problems with anyone or to collaborate to the extent that your programs are identifiably similar. You are not allowed to look at or in any way derive advantage from the existence of project specifications or solutions prepared elsewhere.

If you have any questions as to what constitutes unacceptable collaboration, please talk to the instructor right away. You are expected to exercise reasonable precautions in protecting your own work. Don't let other students borrow your account or computer, don't leave your program in a publicly accessible directory, and take care when discarding printouts.

Examinations - 40% There will be three examinations in this course: two midterms and one final exam. The final examination will be cumulative, although more empahsis will be given to the material covered in the second half of the course. There will be review sessions given in the discussion sections for each of the exams.

Regrading Policy

Regrading on exams will only be done after a written explanation of why the regrade is needed. With the exception of simple addition errors on our part, we will regrade your ENTIRE exam. You grade may or may not change, and it may go up or down.

Cell Phone and Laptop Policy

Cell phones and pagers should be switched off or put on slient alert during class lectures. Laptops and tablets are not permitted during lectures, but may be used during discussion for CLASS USE ONLY. Laptops, phones, and other electronic devices should NEVER be used for unrelated activities such as web surfing, email, facebook, twitter, instant messaging/SMS during lectures or discussion sections. Texting during class or discussions is strictly prohibited. Any student with an electronic device that disrupts the class or is used for anything other than class related activities will lose two (2) points from their final grade (per occurrence).

Policy on Collaboration and Cheating

This all may sound pedantic or even harsh, but I have no sympathy for those that gain unfair advantages over their classmates and misrepresent themselves. All projects in this course are to be done by you. Violation will result in a zero on the project in question, probable failure in the course, and initiation of the formal procedures of the University. We use an automated program and manual checks to correlate projects with each other and with prior solutions. At the same time, we encourage students to help each other learn the course material. As in most courses, there is a boundary separating these two situations. You may give or receive help on any of the concepts covered in lecture or discussion and on the specifics of language syntax. You are allowed to consult with other students in the current class to help you understand the project specification (i.e. the problem definition). However, you may not collaborate in any way when constructing your solution -- the solution to the project must be generated by you working alone. You are not allowed to work out the programming details of the problems with anyone or to collaborate to the extent that your programs are identifiably similar. You are not allowed to look at or in any way derive advantage from the existence of project specifications or solutions prepared elsewhere. You may not use other people's test cases with your own program. You may not look at their code. You may not purchase solutions off the internet, or hire people to code your project. If you have any questions as to what constitutes unacceptable collaboration, please talk to the instructor right away. You are expected to exercise reasonable precautions in protecting your own work. Don't let other students borrow your account or computer, don't leave your program in a publicly accessible directory, and take care when discarding printouts. After this class has ended do not distribute your solution to anyone taking this class here, or anywhere else. As these projects take considerable effort to design, we reuse these projects from year to year. If we are forced to create new projects each year, they will invariable be much less refined, frustrating, and less educational than the current ones. Showing your solution to another student is considered facilitating dishonesty and you will be referred to the Academic Honesty Board. This can result in holding up your graduation, or having a notation put on your transcript. Acts of cheating and plagiarism will be reported to the University Academic Honesty Board. You are responsible for knowing, and will be held to, the University Academic Honesty Policy. This policy is available online:

http://www.umass.edu/dean_students/codeofconduct/acadhonesty/ Discussion of course material is not considered cheating and is strongly encouraged. If you receive substantial help from another person you must acknowledge them in your work. If you use any published or unpublished source in any of your own work, you must give full citation. If you have questions about these policies please see the instructor.


Copyright notice: Many of the materials created for this course are the intellectual property of the instructor. This includes, but is not limited to, the syllabus, lectures and course notes. Except to the extent not protected by copyright law, any use, distribution or sale of such materials requires the permission of the instructor. Please be aware that it is a violation of university policy to reproduce, for distribution or sale, class lectures or class notes, unless copyright has been explicity waived by the faculty member.


This page is online at http://lass.cs.umass.edu/~shenoy/courses/377/syllabus.html