CS 3650 - Computer Systems

Spring 2020

Introduces the basic design of computing systems, computer operating systems, and assembly language using a RISC architecture. Describes caches and virtual memory. Covers the interface between assembly language and high-level languages, including call frames and pointers. Covers the use of system calls and systems programming to show the interaction with the operating system. Covers the basic structures of an operating system, including application interfaces, processes, threads, synchronization, interprocess communication, deadlock, memory management, file systems, and input/output control.

Essential Resources

AMD64 ASM resources


Section Location Time
02 SH 105 1:35pm-3:15pm Tu/Fr
03 INV 019 3:25pm-5:05pm Tu/Fr

Prof Alden Jackson is also offering a section of the course. His section will vary somewhat in assignments and topics.

Staff & Office Hours

Name Location Hours Email
Nat Tuck NI 132 E We 1:30-2:30pm; Fr 5:30-6:30pm ntuck ⚓ ccs.neu.edu
Kaylin Devchand HS 118 Mo 6-8pm devchand.k ⚓ husky.neu.edu
Alec Ge RY 153 Su 1-3pm ge.a ⚓ husky.neu.edu
Sneh Gurdasani SL 009 Mo 11am-1pm gurdasani.s ⚓ husky.neu.edu
Madhur Jain** RY 154* Sa 10am-noon jain.madh ⚓ husky.neu.edu


This is an initial schedule, subject to revision as the semester progresses.

Assignments will frequently be due at 11:59pm on Tuesday.

Week Starts Topics Work Due
1 Jan 6 Intro: Systems; Intro: Assembly -
2 Jan 13 ASM: “Design Recipe”; Large ASM Example; HW01: Linux Setup & Hello Worlds
3 Jan 20 ASM: Syscalls, I/O, the heap; Processes & Memory HW02: ASM, Pointers, Funs
4 Jan 27 C: Arrays & Pointers; C: Data Structures; HW03: ASM Sort
5 Feb 3 A Simple Tokenizer; Syscalls: fork, exec, waitpid; HW04: C Data Structures
6 Feb 10 Building a Shell & pipe; read, write, proc table, vmem; HW05: Shell Tokenizer
7 Feb 17 shared mem & data races; semaphore locks & deadlock; CH1: Unix Shell
8 Feb 24 threads and mutexes; cond vars and atomics HW06: Parallel Sort (Processes)
- Mar 2 Spring Break -
9 Mar 9 malloc: free lists; malloc: optimizations & threads; HW07: Parallel Sort (Threads)
10 Mar 16 Garbage Collection; OS Kernels HW08: Simple Memory Allocator
11 Mar 23 Looking at xv6; Disk Hardware CH2: Advanced Memory Allocator
12 Mar 30 File Systems: FAT; File Systems: ext HW09: Examining xv6
13 Apr 6 The FUSE API; Concurrency solutions HW10: Simple FS
14 Apr 13 Wrap Up; Last class Tuesday CH3: Advanced FS


The textbook for this course is online:

Recommended Readings by Week:

  1. Linux Command Line Tutorial
  2. OSTEP 4
  3. OSTEP 13
  4. OSTEP 13
  5. OSTEP 14
  6. OSTEP 5
  7. OSTEP 15, 16, 18, 31
  8. OSTEP 26, 27
  9. OSTEP 28, 30
  10. OSTEP 17
  11. OSTEP 37, 44
  12. OSTEP 39, 40, 41
  13. OSTEP 43
  14. OSTEP 46, 32, 33

We will also be referring to:


Percentages are approximate.

Letter Grades

The number to letter mapping will be as follows:

95+ = A, 90+ = A-, 85+ = B+, 80+ = B, 75+ = B-, 70+ = C+, 65+ = C, 60+ = C-, 50+ = D, else = F

There may be a curve or scale applied to any assignment or the final grades, in either direction.

Homework and Challenges

There’s a homework or challenge assignment due nearly every week. Assignments in this class is difficult and you are expected to get stuck. Start early so you have time to get unstuck.

Challenges are just like homework, except they’re harder, worth more points, and they are graded more harshly. You’ll want to start early and plan to spend a lot of time on them.

In order to learn the material in this class you must submit the assignments. If at any point you have three unexcused zero grades for assignments that have been graded you will fail the course.

If you fall behind on the course work for any reason, please come to the professor’s office hours to discuss how you can catch up.

Late Work

For all assignments except the last challenge, late submissions will be penalized by 1% for each hour late.

For the final assignment, late submissions will not be accepted after the sun comes up and the TAs start grading.

Late Registration

If you register for the course late, you will have three days to complete each assignment until you are caught up with the rest of the class.


Contesting Grades

Homework and project grades will be posted on Inkfish. If you think your work was graded incorrectly, you can challenge your grade through the following process:

First, go to the office hours of the course staff member who graded your work. If you can convince them that they made a concrete error in grading, they will fix it for you.

If the grader doesn’t agree that the grade was wrong, you can formally contest your grade with the professor. This follows a variant of the “coaches challenge” procedure used in the NFL.

Here’s the formal challenge procedure:

Special Accomodations

Students needing disability accommodations should visit the Disability Resource Center (DRC).

If you have been granted special accomodations either through the DRC or as a student athlete, let me know as soon as possible.

Code Copying & Collabaration Policy

Copying code and submitting it without proper attribution is strictly prohibited in this class. This is plagiarism, which is a serious violation of academic integrity.

Providing solution code to other students is also strictly prohibited.


Lecture Notes

Lecture notes are not starter code, and should not be copied without attribution. As long as attribution is provided, there is no penalty for using code from the lecture notes.

Collaboration and Attribution

Since it’s not plagiarism if you provide attribution, as a special exception to these rules, any code sharing with attribution will not be treated as a major offense.

There is no penalty for copying small snippets of code (a couple of lines) with attribution as long as this code doesn’t significantly impact the intended challenge of the assignment. This should be in a comment above these lines clearly indicating the source (including author name and URL, if any).

If you copy a large amount of code with attribution, you won’t recieve credit for having completed that portion of the assignment, but there will be no further penalty. The attribution must be obvious and clearly indicate both which code it applies to and where it came from.

Posting Code on the Web

Penalty for Plagarism or Providing Solution Code

First offense:

Avoid copying code if you can. If you’re looking at an example, understand what it does, type something similar that is appropriate to your program, and provide attribution. If you must copy code, put in the attribution immediately, every time or you will fail the course over what feels like a minor mistake.