CPU Process Scheduling Simulator

Visualize and compare CPU scheduling algorithms with interactive simulations and detailed performance analysis

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What is CPU Process Scheduling?

CPU scheduling is a fundamental concept in operating systems that determines which process runs when multiple processes are ready to execute

Why Scheduling Matters

CPU scheduling is essential for maximizing CPU utilization and ensuring fair allocation of resources among multiple processes. It helps in achieving:

  • Maximum CPU utilization
  • Fairness to all processes
  • Minimum response time
  • Maximum throughput

Scheduling Criteria

Different scheduling algorithms optimize for different performance metrics:

  • CPU Utilization
  • Throughput
  • Turnaround Time
  • Waiting Time
  • Response Time

Scheduling Types

Scheduling algorithms can be categorized based on their behavior:

  • Preemptive Scheduling
  • Non-Preemptive Scheduling
  • Desktop Systems
  • Batch Systems
  • Real-time Systems

CPU Scheduling Algorithms

Explore different scheduling algorithms and understand how they work

FCFS

First-Come, First-Served

The simplest scheduling algorithm that executes processes in the order they arrive.

  • Non-preemptive
  • Simple to implement
  • Poor performance
  • Convoy effect

Best for: Batch systems

SJF

Shortest Job First

Executes the process with the smallest burst time first.

  • Non-preemptive version
  • Preemptive version (SRTF)
  • Minimal waiting time
  • Hard to predict burst time

Best for: Batch systems

Priority

Priority Scheduling

Executes processes based on their priority levels.

  • Can be preemptive or non-preemptive
  • Important processes first
  • Starvation problem
  • Aging solution available

Best for: Real-time systems

Round Robin

Time Sharing

Each process gets a small unit of CPU time (time quantum).

  • Preemptive
  • Fair to all processes
  • Good for time-sharing
  • Performance depends on time quantum

Best for: Time-sharing systems

Practical Examples

See how different scheduling algorithms handle the same set of processes

Example Process Set

Consider these 4 processes with their arrival times, burst times, and priorities:

Process Arrival Time Burst Time Priority
P1 0 5 2
P2 1 3 1
P3 2 8 3
P4 3 6 2

How Different Algorithms Would Schedule These Processes:

FCFS Scheduling

Processes execute in arrival order: P1 → P2 → P3 → P4

Gantt Chart: | P1 (0-5) | P2 (5-8) | P3 (8-16) | P4 (16-22) |

Average Waiting Time: 6.5

SJF Scheduling

Shortest jobs execute first: P1 → P2 → P4 → P3

Gantt Chart: | P1 (0-5) | P2 (5-8) | P4 (8-14) | P3 (14-22) |

Average Waiting Time: 5.0

Priority Scheduling

Higher priority (lower number) first: P1 → P2 → P4 → P3

Gantt Chart: | P1 (0-5) | P2 (5-8) | P4 (8-14) | P3 (14-22) |

Average Waiting Time: 5.0

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Simulator Features

Discover what makes our CPU scheduling simulator powerful and educational

Interactive Controls

Easily add, remove, and modify processes with intuitive controls

Visual Gantt Charts

See scheduling timelines with color-coded Gantt charts

Algorithm Comparison

Compare multiple algorithms side by side

Performance Metrics

Calculate turnaround time, waiting time, and response time

Step-by-Step Mode

Understand scheduling decisions with step execution

Sample Data

Quickly test with preloaded example processes

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Our interactive simulator helps you understand how different scheduling algorithms work and compare their performance

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