Operating Systems Lab Projects

This repository contains a series of Operating Systems lab assignments implemented using xv6, an educational Unix-like OS.

Table of Contents

1. Lab 1: Introduction to xv6
2. Lab 2: System Calls
3. Lab 3: Process Scheduling
4. Lab 4: Synchronization
5. Lab 5: Memory Management

Lab 1: Introduction to xv6

Description:
This lab introduces students to xv6, a minimalistic OS developed at MIT for educational purposes.
Tasks include:

• Setting up xv6 on QEMU.
• Implementing console improvements like cursor movement and command history.
• Adding support for clipboard operations in the terminal.

Resources:

• Official xv6 repository: xv6-public
• Compilation & Execution:

  make qemu

Lab 2: System Calls

Description:
This lab focuses on system calls in xv6.
Tasks include:

• Understanding the trap mechanism for system calls.
• Implementing new system calls.
• Exploring how user programs interact with the kernel.

Key Concepts:

• System Call Handling
• Trap Gate in xv6
• Wrappers in usys.S

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Lab 3: Process Scheduling

Description:
This lab covers CPU scheduling mechanisms in xv6.
Tasks include:

• Studying Round Robin (RR) scheduling used in xv6.
• Implementing a Multi-Level Feedback Queue (MLFQ) scheduler.
• Ensuring correct context switching between processes.

Key Concepts:

• Context Switching
• Scheduler Implementations
• Process Life Cycle in xv6

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Lab 4: Synchronization

Description:
This lab explores concurrency control and synchronization mechanisms.
Tasks include:

• Understanding spinlocks, sleep locks, and semaphores in xv6.
• Implementing mutex-based synchronization.
• Debugging race conditions in multi-threaded applications.

Key Concepts:

• Spinlocks vs. Sleep Locks
• Race Conditions
• Process Synchronization in xv6

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Lab 5: Memory Management

Description:
This lab covers memory management in xv6.
Tasks include:

• Understanding paging and segmentation.
• Exploring virtual memory translation in xv6.
• Implementing memory allocation mechanisms.

Key Concepts:

• Page Tables & Address Translation
• Physical vs. Virtual Memory
• Swapping & Memory Allocation in xv6

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Setup & Usage

Prerequisites:

• GCC and Make
• QEMU Emulator
• Clone the repository:

  git clone https://github.com/tahamajs/xv6-Modified_OS_Lab_Projects.git
  cd OS-Labs

Running xv6:

make qemu

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Contributors

• Ali Ghanbari & Nesa Abbasi (Lab 1)
• Mehdi Noori & Golrashidi (Lab 2)
• Mohammadreza Nemati & Behrad Elmi (Lab 3)
• Ali Ataollahi & Mehdi Haji (Lab 4)
• Arian Firoozi & Puriya Tajmehrabi (Lab 5)

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License

This project is for educational purposes only. Feel free to use and modify it.