CS 238P - Operating Systems

Please ensure timely submission of your projects by packaging them into a single zip file. This zip file should include the following components, all organized within a dedicated directory: (1) your source code, (2) a README.txt file containing any special comments, issues, and/or notable features, (3) if applicable, an strace output from the invocation of your program, and (4) if applicable, a valgrind report demonstrating the absence of memory leaks. Please stay tuned for further details, which will be communicated during lectures.

1. JIT Compiled Expression Evaluator (October 11, 2024)

   Design a program that accepts a mathematical expression (a string containing the symbols: +, -, *, /, %, (, ), value). This program will dynamically generate a C program based on the input string, invoke a C compiler to create an equivalent loadable module, and then load and execute the machine code equivalent of the C program to produce the evaluated result of the expression. You may use the following to bootstrap the project:

   • Makefile
   • system.h, system.c
   • lexer.h, lexer.c
   • parser.h, parser.c
   • jitc.h, jitc.c
   • main.c

   This project earns you 15% of your class credit. You can earn 2% extra-credit if you implement the sigmoid(double x) function that resides in your main program but is called from the generated C code to transform the final value of the expression (i.e., sigmoid(expression-value)).

2. Userspace Dynamic Thread Scheduler (October 25, 2024)

   Develop a dynamic thread scheduler library with an API akin to the POSIX pthread library, providing the capability to create threads and enable cooperative concurrent execution among them. You may use the following to bootstrap the project:

   • Makefile
   • system.h, system.c
   • scheduler.h, scheduler.c
   • main.c

   This project earns you 15% of your class credit. You can earn 2% extra-credit if you implement an automatic context switch (e.g., every second) from one thread to another without the need for the user threads to call scheduler_yield().

3. Storage Class Memory Manager (November 8, 2024)

   Create a robust memory management system featuring an API reminiscent of the C malloc() function. This system will utilize a file as its underlying storage to ensure persistent data availability across different processes. You may use the following to bootstrap the project:

   • Makefile
   • system.h, system.c
   • term.h, term.c
   • shell.h, shell.c
   • scm.h, scm.c
   • avl.h, avl.c
   • main.c

   This project earns you 15% of your class credit. You can earn 2% extra credit by implementing the scm_free() function and showcasing the correctness of your implementation through the addition of the required code to enable a "remove" command for words.

4. Key/Value File System (November 22, 2024)

   Develop a key/value file system that utilizes raw and direct I/O operations on a block device. Deploy your system on a loop-back device. Ensure that your implementation avoids reliance on kernel buffers for both reading and writing by incorporating efficient write buffering and read caching mechanisms to optimize performance. You may use the following to bootstrap the project:

   • Makefile
   • system.h, system.c
   • term.h, term.c
   • device.h, device.c
   • logfs.h, logfs.c
   • kvraw.h, kvraw.c
   • index.h, index.c
   • kvdb.h, kvdb.c
   • main.c

   This project earns you 15% of your class credit. You can earn 2% extra credit by implementing the ability to store and restore the state of the key/value file system on open/close. Modify the test programs to test this new behaviour.

5. System Performance Monitor (December 6, 2024)

   Create a real-time system monitoring tool similar to the Unix top command that provides two different performance statistics in two different categories (e.g., CPU, memory, network, I/O). You may use the following to bootstrap the project:

   • Makefile
   • system.h, system.c
   • main.c

   This project earns you 15% of your class credit. You can earn 2% extra credit by adding a third category to your tool.

Tools

These tools and environments are essential for successfully completing the projects in this course. Make sure to invest the time needed to attain a proficient level of skill with these applications and systems.

• make, gcc, gdb, gprof, gcov, nm
• valgrind, strace, top, iostat
• lsblk, dd, losetup
• ifconfig, wget
• man
• emacs (because everything else is boring)
  • .emacs
• Linux Machine
  • Ubuntu Server 24.04 LTS
    • ubuntu-24.04-live-server-amd64.iso (8/24/2024)
  • QEMU Machine Emulator & Virtualizer
    • GUI Interface to QEMU
      • UTM.dmg (8/24/2024)
  • Hardware Configuration
    • X86_64
    • 4 Cores
    • 4GB RAM
    • 24 GB Disk
  • Software Configuration
    • $ sudo apt update
    • $ sudo apt install zip
    • $ sudo apt install emacs
    • $ sudo apt install build-essential
    • $ sudo apt install valgrind
    • $ sudo apt install wget
    • $ sudo apt install net-tools
    • $ sudo apt install openssh-server

References

The internet is full of an abundance of valuable resources, encompassing e-books, write-ups, blogs, and Wiki pages that delve into the various subjects covered in this course. Below, you'll find a mini-curated selection, though it's important to note that this list is not exhaustive. You are encouraged to assemble your personal compilation of references to support your learning journey in this course and beyond.

• Operating Systems: Three Easy Pieces
• The GNU C Reference Manual
• ANSI Escape Sequences
• Linux Kernel Coding Style
• GNU Emacs Reference Card
• Xv6 Home Page

*** Commitment to an inclusive learning environment: this class adheres to the philosophy that all community members should enjoy an environment free of any form of harassment, sexual misconduct or discrimination. Please be respectful and kind to one another. ***