Banker's Algorithm
Simulator Interface Overview
The simulator is divided into four main tabs:
- Setup - Configure system resources and process requirements
- Resource Allocation - Visualize current resource distribution
- Resource Request - Request additional resources for processes
- Simulation - Run and visualize the algorithm execution
At the bottom of the interface, you'll find the Action Log which records all system events.
Detailed Tab Functionality
Setup Tab
This tab allows you to configure the initial state of the system:
Available Resources: Set the number of available instances for each resource type (R0, R1, R2)
Process Configuration: Define the maximum resource needs and current allocations for each process
Max: Maximum number of resources a process may request
Allocation: Currently allocated resources to the process
Need: Resources still needed by the process (automatically calculated as Max - Allocation)
- Check System State: Run the safety algorithm to determine if the current configuration is in a safe state
- Reset: Return the simulation to its initial state
Resource Allocation Tab
This tab provides a visual representation of the current resource allocation:
Available Resources: Visual display of free resources in the system
Process Allocation: Progress bars showing allocated resources for each process
The filled portion (red) represents allocated resources
The number in parentheses (yellow) shows needed resources
The maximum value is displayed at the end of each bar
Resource Request Tab
This tab allows you to request additional resources for processes:
Make a Request: Enter the number of resources to request for a specific process
Request Button: Submit the resource request for processing
Current State: View available resources and system status
If a safe sequence exists, it will be displayed
If the system is in an unsafe state, a warning will be shown
Simulation Tab
This tab allows you to run an automatic simulation of the algorithm:
- Simulation Controls: Start, pause, and reset the simulation
- Simulation Speed: Adjust how quickly the simulation progresses
- Simulation Progress: Track which processes have completed and which are pending
- Resource Visualization: See how resources are distributed during the simulation
- Legend: Color coding for different elements in the simulation
Step-by-Step Usage Guide
Basic Usage
Initial Setup:
Start in the Setup tab with the default values
Review the available resources and process requirements
Click "Check System State" to determine if the system is in a safe state
Understanding Resource Allocation:
Navigate to the Resource Allocation tab
Observe how resources are currently distributed among processes
Note the available resources and the needs of each process
Making Resource Requests:
Go to the Resource Request tab
Select a process and enter the resources you want to request
Click "Request" to attempt the allocation
Note that requests will only be granted if they maintain the system in a safe state
Running the Simulation:
Navigate to the Simulation tab
Click "Simulate" to watch processes execute in the safe sequence
Observe how resources are released when processes complete
Use "Pause" to stop at any point or "Reset" to start over
Advanced Usage
Creating Deadlock Scenarios:
In the Setup tab, modify resource allocations to create a potential deadlock
Click "Check System State" to see if the system detects the unsafe state
Try to request resources that would lead to deadlock and observe the denial
Analyzing Safe Sequences:
After running the safety algorithm, examine the safe sequence
In the Simulation tab, observe how following this sequence prevents deadlock
Try different initial configurations to generate different safe sequences
Key Components Explained
Action Log
The Action Log at the bottom of the screen records all system events chronologically, including:
- Resource allocations and releases
- Process completions
- Safety checks
- Request approvals and denials
This log is essential for understanding the sequence of events and debugging issues.
Legend
The Legend in the Simulation tab explains the color coding used throughout the simulator:
- Blue: Available resources
- Red: Allocated resources
- Green: Completed processes
- Yellow: Currently executing process
Info Buttons
Throughout the interface, you'll find info buttons (ⓘ) that provide contextual help about specific components when hovered over.
Tips for Effective Use
- Start Simple: Begin with the default configuration to understand how the algorithm works
- Incremental Changes: Make small changes to see how they affect the system state
- Watch the Action Log: The log provides valuable information about what's happening
- Create Edge Cases: Try to create scenarios where resources are nearly exhausted to see how the algorithm handles them
- Experiment with Speeds: Adjust the simulation speed to better observe the resource allocation process
Common Scenarios
Safe State Example
- Default configuration is in a safe state
- Safe sequence: P0 → P2 → P1 → P3 → P4
- All processes can complete without deadlock
Unsafe State Example
- Allocate most available resources to processes with large maximum needs
- System will detect potential deadlock
- Resource requests that would lead to unsafe states will be denied