Multicore OS Kernel Simulator

A deterministic multi-core kernel simulator in C++20, architected to emulate mutex-based synchronization, demand paging, and virtual memory mechanics.

Key Engineering Features

1. Thread-Safe Process Scheduling

Implemented a deterministic discrete-event simulation of multicore processing.

• Synchronization: Enforces thread safety using std::mutex to prevent race conditions during process context switching.
• Scheduling Algorithms: Configurable Round Robin (RR) and First-Come-First-Serve (FCFS) logic to analyze turnaround times and CPU utilization.

2. Virtual Memory Management (MMU)

Engineered a simplified Memory Management Unit to handle resource constraints.

• Demand Paging: Implements lazy allocation, fetching pages from a backing store only when a Page Fault occurs.
• Memory Protection: Enforces strict process isolation; unauthorized memory access triggers immediate termination.

3. Interactive Shell (CLI)

Built a custom shell to manage the OS state dynamically, inspired by tools like screen and nvidia-smi.

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System Commands

The simulator exposes a shell interface for system administration:

Command	Description
process-smi	System Management: Displays memory usage and CPU core allocation.
vmstat	Virtual Memory: Detailed stats on active/inactive pages and paging rates.
screen -s <name>	Spawns a process with defined memory requirements.
screen -r <name>	Context switches the terminal to a running process.
scheduler-start	Triggers the CPU scheduling algorithm.
help	Displays full command list.

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Build & Run

Prerequisites

• C++20 Compatible Compiler (GCC 10+ or Clang)

Compilation

Windows (PowerShell):

g++ -std=c++20 -Wall -Wextra -Werror Main.cpp Kernel.cpp ShellPrompt.cpp Process.cpp Processinstruction.cpp -o csopesy.exe

macOS / Linux (Bash):

g++ -std=c++20 -Wall -Wextra -Werror Main.cpp Kernel.cpp ShellPrompt.cpp Process.cpp Processinstruction.cpp -o csopesy

Usage

1. Configure: Edit config.txt in the root directory to set RAM size, Time Quantum, and Core count.
2. Run:

./csopesy

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Credits

• Angeles, Marc Andrei D.: Lead Architect (Core Kernel Rewrite, Scheduler, Memory Paging).
• Limbag, Daniella Franxene P.: Initial Prototype & Base Implementation.
• Gomez, Dominic Joel M. & Iral II, John Rovere N.: Reporting Modules & Documentation.