pwrzv

A Rolls-Royce–inspired performance reserve meter for Linux systems. Elegant, minimal, and focused on what really matters: how much performance your machine has left to give.

🛠 What is pwrzv?

Inspired by the Power Reserve gauge in Rolls-Royce cars — which shows how much engine power is still available — pwrzv brings the same philosophy to Linux systems. Instead of showing raw usage, it estimates how much headroom remains in your system's core resources.

It provides a simple 0–5 score, calculated from multiple real-time metrics:

• CPU usage and I/O wait
• Memory availability
• Swap activity
• Disk I/O
• Network throughput
• File descriptor consumption

All inputs are weighted and transformed via sigmoid functions to reflect practical bottlenecks, not just raw numbers.

🚦 Example Output

Basic Usage

$ pwrzv
System Metrics:
  CPU Usage: 12.34% (iowait: 0.00%)
  Memory Available: 78.50%
  Swap Usage: 0.00%
  Disk I/O Usage: 5.10%
  Network I/O Usage: 0.75%
  File Descriptor Usage: 3.42%
Power Reserve Score: 5 (Excellent - Abundant resources)

Detailed Analysis

$ pwrzv --detailed
=== System Power Reserve Analysis ===

System Metrics:
  CPU Usage: 12.34% (iowait: 0.00%)
  Memory Available: 78.50%
  Swap Usage: 0.00%
  Disk I/O Usage: 5.10%
  Network I/O Usage: 0.75%
  File Descriptor Usage: 3.42%

Component Scores (0-5):
  CPU:              5
  I/O Wait:         5
  Memory:           4
  Swap:             5
  Disk I/O:         5
  Network I/O:      5
  File Descriptors: 5

Overall Assessment:
  Power Reserve Score: 4 (Good - Ample resources)
  Bottlenecks: None

✅ System has ample performance headroom.

📦 Installation

From Source

git clone https://github.com/kookyleo/pwrzv.git
cd pwrzv
cargo install --path .

Using Cargo

cargo install pwrzv

🖥️ Platform Support

pwrzv only supports Linux systems. Other platforms will display an error message.

Check platform compatibility:

pwrzv --check-platform

🔧 Usage

Command Line Interface

# Basic usage
pwrzv

# Detailed component analysis
pwrzv --detailed

# JSON output
pwrzv --format json

# YAML output
pwrzv --format yaml

# Quiet mode (suppress warnings)
pwrzv --quiet

# Check platform compatibility
pwrzv --check-platform

Library Usage

use pwrzv::{PowerReserveCalculator, PwrzvError};

fn main() -> Result<(), PwrzvError> {
    let calculator = PowerReserveCalculator::new();
    let metrics = calculator.collect_metrics()?;
    let score = calculator.calculate_power_reserve(&metrics)?;
    println!("Power Reserve Score: {}", score);
    Ok(())
}

Detailed Analysis

use pwrzv::{PowerReserveCalculator, PwrzvError};

fn main() -> Result<(), PwrzvError> {
    let calculator = PowerReserveCalculator::new();
    let metrics = calculator.collect_metrics()?;
    let detailed = calculator.calculate_detailed_score(&metrics)?;
    
    println!("Overall Score: {} ({})", detailed.final_score, detailed.level);
    println!("Bottlenecks: {}", detailed.bottleneck);
    println!("CPU Score: {}", detailed.component_scores.cpu);
    Ok(())
}

Custom Configuration

use pwrzv::{PowerReserveCalculator, SigmoidConfig, PwrzvError};

fn main() -> Result<(), PwrzvError> {
    let mut config = SigmoidConfig::default();
    config.cpu_threshold = 0.8;  // More sensitive CPU threshold
    
    let calculator = PowerReserveCalculator::with_config(config);
    let metrics = calculator.collect_metrics()?;
    let score = calculator.calculate_power_reserve(&metrics)?;
    println!("Power Reserve Score: {}", score);
    Ok(())
}

📊 Scoring System

The scoring system uses sigmoid functions to map resource utilization to a 0-5 scale:

• 5 (Excellent): Abundant resources, system running smoothly
• 4 (Good): Ample resources available, good performance
• 3 (Moderate): Adequate performance, resources sufficient
• 2 (Low): Resource constrained, consider optimization
• 0-1 (Critical): System under heavy load, immediate attention needed

How It Works

1. Resource Collection: Gathers metrics from /proc filesystem
2. Normalization: Converts raw metrics to 0-1 scale
3. Sigmoid Transformation: Applies configurable thresholds and curves
4. Bottleneck Detection: Takes the minimum score (worst resource)
5. Final Scoring: Maps to 0-5 range with level descriptions

🧪 Philosophy

While most system monitors highlight how much is used, pwrzv tells you how much is left. This makes it a useful tool for:

• Minimal dashboards - Single metric overview
• Autoscaling decisions - When to scale up/down
• Performance monitoring - Proactive resource management
• System health checks - Quick status assessment

🔄 Examples

Run the included examples:

# Basic usage example
cargo run --example basic_usage

# Detailed analysis with different configurations
PWRZV_JSON_OUTPUT=1 cargo run --example detailed_analysis

🧪 Testing

# Run all tests
cargo test

# Run only unit tests
cargo test --lib

# Run documentation tests
cargo test --doc

# Run examples
cargo run --example basic_usage

📚 API Documentation

Generate and view the full API documentation:

cargo doc --open

🤝 Contributing

1. Fork the repository
2. Create a feature branch
3. Add tests for new functionality
4. Ensure all tests pass: cargo test
5. Submit a pull request

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

🙏 Acknowledgments

• Inspired by the Power Reserve gauge in Rolls-Royce automobiles
• Built with Rust for performance and reliability
• Thanks to the Linux kernel for providing comprehensive /proc metrics