Course Description - CSCI 402, Spring 2018, All Sections

Focus		Late Policy		Fairness
Textbooks		Note From A Doctor		Auditing
Syllabus / Topics Covered		Regrade Policy		E-mail
Homework Assignments		Office Hours		Academic Integrity Policy
Projects		Extra Credit		Diversity Statement
Exams		Implicit Student Agreement		Academic Calendar
Grading		Student Responsibilities		Additional Resources

• T. W. Doeppner, Operating Systems In Depth: Design and Programming, 1st Edition, Wiley, 2010. (Please note that the Kindle Edition of this book is identical to the printed version of this book.)

Recommended resources:

• B. Kernighan and D. Ritchie, C Programming Language, 2nd Edition, Prentice Hall, 1988. (Since the C programming language is a proper subset of the C++ programming language, if you know C++, you pretty much know C already. However, things available in C++, such as strings and streams, are not be available in C. So, you need to know how to do things such as manipulating null-terminated array of characters and performing I/O in C.)

• Scott Chacon, Pro Git (a free online book). You may want to use git when you do your programming assignments.

• Joe Topjian, Unix for the Beginning Mage. (If you are not familiar with Unix, please read this tutorial as soon as possible.)

• David Rusling, The Linux Kernel. (This is for your reading pleasure. We will not cover this book in our class.)

• Wk 1-2: Introduction to Operating Systems (OSID Ch 1)
  • A Brief History of Operating Systems
  • A Simple OS
  • Beyond a Simple OS
• Wk 3-4: Multithreaded Programming (OSID Ch 2)
  • Why Threads
  • Programming with Threads
  • Synchronization
  • Thread Safety
• Wk 5-6: Basic Operating Systems Concepts (OSID Ch 3)
  • Context Switching
  • I/O Architecture
  • Dynamic Storage Allocation
  • Linking and Loading
  • Booting
• Wk 7-8: Operating-System Design (OSID Ch 4)
  • A Simple System
• Wk 8-9: Process Management (OSID Ch 5)
  • Threads Implementations
  • Interrupts
• Wk 10-11: File Systems (OSID Ch 6)
  • The Basics of File Systems
  • Crash Resilency
  • Directories and Naming
  • Multiple Disks
  • Flash Memory
  • Case Studies
• Wk 12-13: Memory Management (OSID Ch 7)
  • Memory Management in the Early Days
  • Hardware Support for Virtual Memory
  • OS Issues
• Wk 14: Operating-System Design (OSID Ch 4)
  • Virtual Machines
  • Microkernels
• Wk 15: Process Management (OSID Ch 5)
  • Scheduling

All projects will require a fairly strong background in C programming, which you are expected to pick up on your own. There will be 1 to 2 warmup programming assignments at the beginning of the semester to make sure that you are up to speed with C and doing multi-threading in C.

All kernel programming assignments are extremely difficult and can be very very time-consuming. You can do these assignments in teams of two or three students. Since the kernel programming assignments are interrelated, you must pick a team at the beginning of the semester and stick with the team till the end of the semester. If you'd prefer, you can do the kernel assignments by yourself.

For more information, please see the projects web page.

Exam Locations

Exam Questions

There are three types of exam questions that I usually ask. The first type is a calculation-type question. Pretty much anything that can be calculated/computed by running an algorithm can be asked in an exam. For example, I can ask you to compute a schedule using a particular scheduling algorithm. I can also ask you to calculate average waiting time for a particular scheduling policy. (Calculators will not be permitted during exams, but you can leave your answers as fractions for non-integer answers.) I may also ask you about what a data structure (e.g., tree, hash table, etc.) would look like after certain operations have been performed on it. Usually, for this type of questions, you must get the answer right and there is not much room for partial credits.

The second type is multiple-choice questions. Unless explicitly stated, every multiple choice questions has one or more correct answers. (Even if a question asks, "which statements are correct", it can have one or more correct answers.) Please check all the correct ones and don't check any of the incorrect ones. There is a penalty for selecting incorrect answers (you will lose 1 point for every such selection). Please note that an incorrect statement can never be a correct answer (unless the question asks you to select statements that are incorrect).

The scoring of multiple-choice questions is as follows. Multiple-choice questions are worth 2 points each and you are given 5 selections for each such question. It can have 1 to 4 correct answers. If a multiple-choice question has 1, 2, or 4 correct answers, for each correct answer that you have selected, the number of points you will get would equal 2 divided by the total number of correct answers. If it has 3 correct answers, you will get 1 point for selecting one of the correct answers and you will get 0.5 point each for selecting additional correct answers. Therefore, if you mark all the correct answers and don't mark any of the incorrect answers, you will get 2 points. But if you have selected incorrect answers, we will subtract 1 point for each such selected. In the end, if the total score for a problem is below zero, a score of zero will be assigned. Let's look at a concrete example. If a problem has 3 correct answers and you selected 2 correct ones and one incorrect one. You will get 1.5 points for the correct answers and -1 point for the incorrect answer. So, you will end up with 0.5 point. On the other hand, if you have only selected one of the correct answers and didn't select anything else, you will end up with 1 point.

The third type is to ask you to give the best answer for a given question. (If a question says, "In N words or less...", it's giving you a hint that the answer should be N words or less. You don't have to answer in N words or less. There is one exception though. If the question is of the fill-in-the-blanks type where N is small, then you must not use more than N words.)

For this type of question, you get credit for including the "best answer". You may get deductions for including "bad answers". What you need to demonstrate is that you can distinguish between answers of different quality and write down the best answer. (For these questions, there is no need to write complete English sentences when you answer exam questions. Just give me the important stuff!)

Let me give a couple of silly examples (with questions that's not in the scope of any exam).

• "For programming assignments (well, this is not our policy, I'm just using this as an example), when is 'plagiarism' considered taking place? If your answer is "when you take someone else's work and claim it to be yours", then you will get full credit. If your answer is, "when you submit someone else's work", you probably will not get full credit (since you are allowed to use code given to you in another class that you have taken if you cite it properly).

• "What is the fairness policy of this class?" If your answer is, "whatever the instructor offer to one student, he must offer it to the rest of the class," then you will get full credit. If your answer is, "the instructor must be fair to every student," you probably will not get much partial credit.

Weenix Questions

Lecture Slides

Exam Grading

In general, better answers may score more points. If you give very high level and generic answer that's generally true or basically just repeat the question, you probably will get very little partial credit for it! You need to answer a specific question with a specific answer. On the other hand, if the question called for a general answer and the answer you gave only applies to some specific examples, you probably will get very little partial credit for your answer. You must not give examples to answer general questions.

If I asked a question straight from the lecture slides, the best/correct answer is the one on the lecture slides. If you disagree with what's on the slides, you must complain when you are studying for the exam, i.e., before the exam. Once the exam starts, it's too late to complain that you don't like the answer on the lecture slides. In an exam, if you give an answer that's different from the lecture slides, you may receive partial credits, at the discretion the TA. Finally, I reserve the right to ask about things that I think you should know and not on lecture slides.

Class Participation:		4%	(extra credit)
Projects:		40%
Midterm Exam:		25%
Final Exam:		35%

Two methods will be used to calculate your final letter grade:

(1)		Use a modified curve (i.e., we won't necessarily assign an equal number of failing grades as passing grades) based on the numeric score calculated above
(2)		Use the following fixed scale (to encourage cooperation and friendly association amongst students): Percentage Letter Grade 91% or higher A 82-91% A- 73-82% B+ 64-73% B 55-64% B- 46-55% C+ 37-46% C 28-37% C- below 28% F

Please also note the following:

• No other methods will be considered. (So, please do not ask the instructor to take how much you have improved since the beginning of the semester into account. You are expected to try your best from the beginning!)

• According to the above guidelines, it should be clear that it is possible to get a grade of C or below for individuals who perform very poorly (i.e., you should not assume a B- or even C+ if you perform very poorly, according to the guidelines above.) However, we hope that everyone will perform well.

• We will not assign incompletes unless you miss the final exam for documented illness or documented family emergency (in accordance with USC policy).

So, if you visit a doctor at the Student Health Center, please make sure you fill out one of these forms, check the "limited discussion with faculty" checkbox, get it stamped, signed, and dated by someone there (a clerk/receptionist would sign at the "witness" line), and bring it back to me. This would satisfy the "note from a doctor" requirement so that you can get an extension.

If you visit a doctor somewhere else, please either bring a "note from the doctor" or a similar authrozation letter so I can contact them.

Assignment Regrades

All requests to change grading of programming assginments must be submitted in writing within one week of the time the initial grade was announced to you. Requests must be specific and explain why you feel your answer deserves additional credit. A request to re-grade an assignment can result in the entire assignment being re-evaluated and as a result the score of any part of the assignment be increased or lowered as appropriate.

If you have made multiple submissions and after you have received your grade and you noticed that what we graded wasn't the submission you wanted us to grade, you may ask us to to grade a different submission. In this case, we will deduct 20 points. By default, we will grade the last submission. What you should do is to go through the verification procedure and make sure that we are grading the submission you want us to grade. If you discover that the submission we are grading is not the one you want us to grade and if you tell us soon after grading starts, there would be no penalty.

Each TA is required to use one standard when grading all the exams in his/her section. Therefore, regrade for exams is not about arguing for points but about whether the TA has made a mistake in grading or not. If you think the TA has made a mistake, you should write down (on the cover page of the exam) which problem/subproblem needs to be regraded and why you think the TA has made a mistake. Plese limit the description of your rationale to be only one sentence long (e.g., "my answer is also correct", "I deserve more partial credit", etc.). There is no need to discuss your answer or your rationale with the TA since the TA is required to grade entirely based on what you wrote on the exam paper (and thus must ignore everything you said during a regrade session).

Please be familiar with the grading rules for multiple choice questions. The TA must stick to those rules when giving points for multiple choice questions.

After the regrade appointment is over, the TA will look over your answers in order to determine if a mistake was made (i.e., the actual regrade only happens after your regrade appointment). If a mistake was made, the TA will need the instructor's approval in order to return points to you. If I approve of a grade change, I will send you a private e-mail informing you that I have updated my grading records. Please understand that if your grade stays the same, I will not send you an e-mail. Therefore, if you don't get such an e-mail from me, it means that your grade did not change.

To be fair to all, we must assume that you wrote what you meant and meant what you wrote. Every student gets a maximum of one regrade appointment. So, please use your time wisely during a regrade session and not spending much time telling the TA what you were thinking when you were writing down your answers since the TA must grade based on what you wrote and not what you were thinking..

Regarding lecture materials, please understand the purpose of office hours is to clarify lecture materials. I will not repeat lecture materials during office hours. If you miss a lecture, it's your responsibility to figure out how to make up for the missing lecture materials. Since lectures are recorded for the DEN section, you should review DEN lecture videos before you ask me to clarify lecture materials.

If you need to see me outside of office hours, it's best that you make an appointment (and reserve a timeslot) so I can make sure to be in my office when you visit. Making an appointment is not a big deal! Just send an e-mail to me and tell me when you are available to meet and go from there.

1. Post timely (i.e., within 24 hours of the original post), useful, and insightful answers to the class Google Group in response to questions posted by other students regarding kernel programming assignments.
   • The maximum number of extra credit points you can get is 10 points for each of the kernel assigments (on a 100-point scale).
   • You can lose extra points you have earned if you post something unprofessional to the class Google Group or exhibit poor netiquette. Please always be courteous and professional.
   • The instructor (or the TA) will decide to award extra credit or not at his discretion and will keep track of scores. (Harrassing the TAs or course producers is considered unprofessional behavior.)
   • You probably won't get extra credit points if you repeat exactly what others have already posted (so, you should always try to add something useful to what others have posted).
   • You probably won't get extra credit points if you respond to a post 24 hours beyond the time of the original post (unless you have something very insightful to add).
   • If you want to be considered for extra credit, you have to reply to an existing post (i.e., do not start a new thread).
   • You definitely won't get extra credit points if you respond to a post via private e-mail.
   • If you post something good, it's your responsibility to verify that it has been posted to the Google Group.

2. To encourage you to do your programming assignments early, you will get extra credit if you turn in programming assignment 2 or 3 days early.
   • If your submission is more than 72 hours before the posted deadline, you get an extra 10%, i.e., your actual score will be 1.1 times your graded assignment score.
   • If your submission is between 48 and 72 hours before the posted deadline, you get an extra 5%, i.e., your actual score will be 1.05 times your graded assignment score.
   The figure below summarize the early submission extra credit schemes.

   

3. Earn class participation extra credit.

Please note that due to my fairness policy, I cannot offer any individual extra credit work.

This policy also holds for programming assignments. In this class, we will use sophisticated automated program checkers to detect cheating. Be aware that the program checkers have demonstrated very good results and are widely used within the academic community. Any student caught cheating will be given zero credit and will be disciplined.

It is the students responsibility to submit their assignments electronically in time.

For students who satisfied the prerequisite at other universities or through work experience, this course assumes that you understand data structures, basic algorithms, and UNIX programming. You should be able to write large programs in C. No special assistance or consideration will be offered if your background is inadequate.

You must keep up with the assigned readings. If you come to class without having read the chapter for the corresponding lecture, you're unlikely to learn anything at all from the lecture. In particular:

1. You are expected to read the relevant textbook chapter thoroughly. Not all details will be covered in class, and the exam may test material covered in the textbook but not discussed in class.
2. I expect you to attend every class meeting. If you do happen to miss a session, you are responsible for finding out what material was covered and if any administrative announcements were made. Also, please be aware that all exams (in the summer session) are in-class, so you will be expected to at least attend those lectures.

Pretty much all class related announcements will be sent through the class Google Group. Therefore, you are required to be a member of this Google Group. As messages are posted to the class Google Group, you will receive e-mail notifications and you should read all these class-related e-mails. Please see instructions on how to get on this group (you should do this as soon as possible).

You are strongly encouraged to send private e-mail messages to me if you have questions about programming assignments or lectures. If the answer is appropriate for the entire class, I would normally anonymize the reply and send the reply through the class Google Group and bcc a copy to you. So, please don't be shy to ask questions!

One type of question I often get over e-mail or see in the class Google Group is:

Here is my understanding of X. Am I right (or is this correct)? Correct me if I'm wrong...

Another type of question I often get is the following:

I am thinking about not following the spec or grading guidelines and would like to do this instead. Is it acceptable (or is this okay)?

Programming:

• C Programming (by Steve Holmes at the University of Strathclyde in Glasgow, England) - includes notes on make, separate compilation, file I/O, etc.
• Makefile tutorial (at Colby College)
• Steve's Software Trek (by Steve Karg) - includes some useful C/C++ source code for string manipulation, INI file manipulation, etc.
• C Examples - lots and lots of sample C code for basic stuff.
• C/C++ at USC from USC ITSWeb
• Online Judge online portal for IT interview

• Ubuntu Linux
• cygwin (BSD system with X11R6 on Windows XP)
• Some Often-used UNIX Commands
• Unix commands (more complete, from University of Utah)
• UNIX Shell Programming (Chapter 2 of this book gives a good introduction to UNIX)
• UNIXhelp for Users from the University of Edinburgh
• UNIX Tutorial for Beginners from the University of Surrey
• Introduction to the Unix Shell from the Canisius College
• Introduction to C Shell Programming from the Canisius College
• C/C++ Documentation (compiling, linking, additional libraries, include files) from USC ITSWeb
• Understanding C by learning assembly
• UNIX Documentation (concepts, commands, X-Windows) from USC ITSWeb
• Editors on most UNIX systems
  • Vi Text Editor Documentation from USC ITSWeb
  • EMACS Text Editor Documentation from USC ITSWeb
  • Pico Text Editor Documentation from USC ITSWeb
• Beej's Quick Guide to GDB
• Richard Stallman's gdb Tutorial
• GPROF Tutorial - How to use Linux GNU GCC Profiling Tool
• USC ITS Resources
  • General information on operating systems, productivity applications, Internet connectivity, e-mail and web publishing at USC, can be found at the ITS software site. You can click on your operating system and download useful software from there. For example, for the Windows platform, you can find things like X-Win32 and FileZilla there (looks like the very popular PuTTY is no longer available for downloads from ITS, but you can get it from here).
  • UNIX Computing Accounts for Students (SCF).
  • Examples of using ssh and sftp at usc (replace "mizar.usc.edu" with "nunki.usc.edu" when doing our warmup programming assignments).

• Kernel 101 - Let's write a Kernel