Welcome to CS31, Intro to Computer Systems.
This course is a broad introduction to computer systems that focuses on how a computer works and how programs run on computers. We examine the hardware and software components required to go from a program expressed in a high-level programming language like C or Python to the computer actually running the program. This course takes a bottom-up approach to discovering how a computer works, beginning with elementary gates and proceeding all the way up to parallel and distributed computing. Topics include data representation, logic circuits, machine organization, assembly and machine code, memory, I/O, the stack, the operating system, compilers, processes and threads, and synchronization. Prerequisite: Completion of CS21 or its equivalent.
Outside of office hours and ninja sessions, the best way to ask questions is to post on the piazza forum. The ninjas and I will check piazza regularly, and will do our best to answer your questions promptly. When possible, you should post your questions publicly on piazza (as opposed to private posts or emails) so that all students can benefit from the answer.
There is no required textbook for this course. Instead, we will use readings from the web as our introduction to new material. The textbook we've used in the past for this course is Computer Systems: A Programmer's Perspective by Bryant and O'Hallaron. Because it's a great reference, two copies are on reserve in Cornell. I will list corresponding sections for this book, when applicable.
| 35% | Lab assignments |
| 25% | Midterm exam |
| 25% | Final exam |
| 5% | Written homework |
| 5% | Reading quizzes (lowest three dropped) |
| 5% | Class participation |
Labs will typically be assigned in class on Wednesday and will be due before midnight the following Tuesday. You are strongly encouraged to start early and to attend the ninja sessions for extra practice.
You must submit your assignments electronically by pushing to your assigned git repository. You may push your assignment multiple times, and a history of previous submissions will be saved. You are encouraged to push your work regularly.
To help with cases of minor illnesses, athletic conflicts, or other short-term time limitations, all students start the course with three "late assignment days" to be used at your discretion, with no questions asked. To use your extra time, you must email me after you have completed the lab and pushed to your repository. You do not need to inform anyone ahead of time. When you use late time, you should still expect to work on the newly-released lab during the following lab section meeting. The professor and ninjas will always prioritize answering questions related to the current lab assignment.
Your late days will be counted at the granularity of full days and will be tracked on a per-student (NOT per-partnership) basis. That is, if you turn in an assignment five minutes after the deadline, it counts as using one day. For partnered labs, using a late day counts towards the late days for each partner. In the rare cases in which only one partner has unused late days, that partner's late days may be used, barring a consistent pattern of abuse. You may use late days for written homeworks, however I strongly recommend against it. Late labs (without late days) will receive zero credit, while late written homework will receive half credit if submitted less than 2 days late, zero credit otherwise. Further, each written assignment is worth about one percent of the course grade, while each lab is worth over three percent.
If you feel that you need an extension on an assignment or that you are unable to attend class for two or more meetings due to a medical condition (e.g., extended illness, concussion, hospitalization) or other emergency, you must contact the dean's office and your instructors. Faculty will coordinate with the deans to determine and provide the appropriate accommodations. Note that for illnesses, the College's medical excuse policy, states that you must be seen and diagnosed by the Worth Health Center if you would like them to contact your class dean with corroborating medical information.
Even if you do not fully complete an assignment, you should submit what you have done to receive partial credit.
The CS labs are open 24 hours a day, 7 days a week for you to use for CS lab assignments.
Discussing ideas and approaches to problems with others on a general level is fine (in fact, we encourage you to discuss general strategies with each other), but you should never read anyone else's code or let anyone else read your code. All code you submit must be your own with the following permissible exceptions: code distributed in class, code found in the course text book, and code worked on with an assigned partner. In these cases, you should always include detailed comments that indicates on which parts of the assignment you received help, and what your sources were.
Failure to abide by these rules constitutes academic dishonesty and will lead to a hearing of the College Judiciary Committee. According to the Faculty Handbook: "Because plagiarism is considered to be so serious a transgression, it is the opinion of the faculty that for the first offense, failure in the course and, as appropriate, suspension for a semester or deprivation of the degree in that year is suitable; for a second offense, the penalty should normally be expulsion."
The spirit of this policy applies to all course work, including code, homework solutions (e.g., proofs, analysis, written reports), and exams. Please contact me if you have any questions about what is permissible in this course.
For this course, it is fine to help each other with using
utilities and tools (Unix, C++, Sqlite, man, git, make, ...), and with
reading and understanding the assignments.
However, you should avoid discussing the details of your solution with
anyone other than your lab partner, and you should never look at
anyone else's code for a solution to a lab (or to a similar project).
In addition, there are many useful on-line resources of which you
should take advantage. However, make sure that you do not use these
resources in such a way that it violates the spirit of our Academic
Integrity statement. For example, should you post questions to on-line
forums or mailing lists seeking a solution to the specific problem you
are asked to solve. Basically, the solution and code that you submit as your
own should be your own. If you are unclear about what type of
collaboration is okay and what type is not, ask me about your
situation before proceeding.
To receive an accommodation for a course activity, you must have an Accomodation Authorization letter from Leslie Hempling and you need to meet with me to work out the details of your accommodation at least one week prior to the activity.
You are also welcome to contact me privately to discuss your academic needs. However, all disability-related accommodations must be arranged through Leslie Hempling in the Office Of Student Disability Services.