Project Detail

CPU Scheduler Simulation

Unix-style process scheduling simulation written in C

Developed a Unix-style CPU scheduler simulation implementing process scheduling, priority recalculation, quantum management, and process state transitions.

Overview

Project Overview

This project implemented a simulated CPU scheduler capable of managing process execution in a dynamic operating system environment. The scheduler handled arrivals, blocking, termination, quantum expiration, and priority-based scheduling decisions.

Core Features

Round Robin scheduling within priority queues.
Dynamic priority recalculation.
Process blocking and unblocking simulation.
Quantum management.
CPU-bound and I/O-bound process handling.
Clock tick simulation at 60Hz.
Context switching logic.

Technical Concepts

Operating Systems
CPU Scheduling Algorithms
Process State Management
Queue Structures
Priority Scheduling
C Programming
Systems Simulation

Skills Demonstrated

Systems-level logic development.
Algorithm implementation.
Complex state management.
Structured program design.
Debugging and troubleshooting.
Performance-oriented programming.

Live Scheduler Simulation

[CLOCK TICK 1042]

PID 18 -> RUNNING -> PRI 0

PID 11 -> BLOCKED -> Waiting for I/O

PID 22 -> READY -> Queue Priority 1

Context switch triggered...

Quantum expired -> recalculating priority

Scheduling next process...

PID	CPU Used	State	Priority	Quantum Used	Block Time
18	42	RUNNING	0	4	6
22	17	READY	1	0	3
11	23	BLOCKED	-1	2	2

Implementation

Source Code

while (next_pid < 100)
{
    process_clock_tick();
    terminate_running_process();
    preempt_running_process();
    unblock_processes();
    add_new_processes();
    schedule_next_process();
}