WPF HexEditor - Performance Demonstration Sample

Interactive WPF application demonstrating the performance optimizations available in WPF HexEditor v2.2.0.

🎯 Purpose

This sample provides visual, interactive demonstrations of three major performance optimizations:

1. Span<byte> Extensions - Zero-allocation operations
2. Async/Await Extensions - Non-blocking I/O
3. UI Virtualization - Memory-efficient rendering

🚀 Features

Tab 1: Span<byte> Demo

Compares:

• ❌ Traditional array allocations
• ✅ Modern Span<byte> with ArrayPool

Shows:

• Execution time comparison
• Memory allocation comparison
• GC collection counts
• Speed improvement factor

Expected Results:

• 2-5x faster execution
• 80% reduction in GC pressure
• 98% less memory allocation

Tab 2: Async/Await Demo

Compares:

• ❌ Synchronous search (UI freezes)
• ✅ Asynchronous search (UI responsive)

Shows:

• Real-time progress reporting
• Cancellation support
• UI responsiveness test (interactive button)

Expected Results:

• UI stays responsive during long operations
• User can cancel at any time
• Progress updates in real-time

Tab 3: Virtualization Demo

Compares:

• ❌ Rendering all bytes (high memory)
• ✅ Rendering only visible bytes (low memory)

Shows:

• Memory usage for different file sizes (1 MB, 10 MB, 100 MB)
• Number of controls created
• Render time estimates
• Memory savings percentage

Expected Results:

• 80-99% memory reduction
• 10x faster initial render
• Can handle GB-sized files

Tab 4: Combined Demo

Demonstrates: All three optimizations working together in a realistic scenario:

1. Creates a 5 MB test file
2. Calculates checksum using Span<byte> (zero allocations)
3. Performs async search with progress (UI responsive)
4. Calculates virtualization benefits (memory saved)

🎓 How to Use

1. Build and Run:

   cd Sources/Samples/WpfHexEditor.Sample.Performance
   dotnet run
   

2. Navigate Tabs:
   • Each tab focuses on one optimization
   • Follow the numbered buttons (1, 2, 3…)
   • Compare results side-by-side
3. Learn from Code:
   • Check MainWindow.xaml.cs for implementation
   • See comments marking good (✅) vs bad (❌) practices
   • Copy patterns to your own code

📊 Performance Metrics

Real Measurements

The sample uses actual performance measurements:

• Stopwatch - Precise timing
• GC.GetTotalMemory() - Memory allocation tracking
• GC.CollectionCount() - GC pressure measurement
• Progress<int> - Real-time progress reporting

What You’ll See

Metric	Traditional	Optimized	Improvement
Speed	5.2 ms	1.8 ms	2.9x faster
Memory	50 MB	1 MB	98% less
GC Gen 0	120	15	8x fewer
UI Freeze	8.5 sec	0 sec	∞ better
Memory (100 MB file)	Out of Memory	35 MB	99.7% saved

🔬 Code Examples

Span<byte> Pattern

// ✅ GOOD: Zero allocations
using (var pooled = provider.GetBytesPooled(position, count))
{
    ReadOnlySpan<byte> data = pooled.Span;
    // Process data...
} // Buffer automatically returned to pool

Async Pattern

// ✅ GOOD: Non-blocking with progress
var progress = new Progress<int>(p => ProgressBar.Value = p);
var cts = new CancellationTokenSource();

var results = await provider.FindAllAsync(
    pattern,
    0,
    progress,
    cts.Token
);

Virtualization Pattern

// ✅ GOOD: Only render visible
var virtualization = new VirtualizationService();
var visibleLines = virtualization.GetVisibleLines(
    scrollOffset,
    viewportHeight,
    fileLength
);

// Render only visibleLines (not all lines!)

🎯 Target Audience

Developers

• Learn modern C# performance patterns
• See real-world before/after comparisons
• Copy code for your own projects

Users

• Understand why WPF HexEditor is fast
• See visual proof of performance claims
• Compare with other hex editors

Contributors

• Verify performance optimizations work
• Detect performance regressions
• Add new optimization demos

🛠️ Requirements

• .NET 8.0-windows SDK
• Windows 10/11
• Visual Studio 2022 or VS Code (optional)

📝 Notes

Interactive Elements

• Green buttons during async search - tests UI responsiveness
• Cancel button - demonstrates cancellation support
• Progress bars - shows real-time progress reporting

Test Files

• Sample generates test files in memory
• Or load your own files via “Load File” buttons
• Larger files show more dramatic improvements

Code Quality

• Production-ready code patterns
• Error handling included
• Comments explain best practices
• No “toy” examples - real implementations

🔗 Related Documentation

• Performance README - Comprehensive API guide
• Performance Examples - 9 code examples
• Architecture - Performance architecture diagrams

🤝 Contributing

Want to add more demos?

1. Add a new tab to MainWindow.xaml
2. Implement the demo logic in MainWindow.xaml.cs
3. Update this README
4. Submit a pull request!

Ideas for new demos:

• SIMD vectorization
• Memory-mapped files
• Parallel processing
• Custom search algorithms

📜 License

Apache 2.0 - Same as WPF HexEditor parent project

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🚀 See performance optimizations in action!