README.md

🔍 Backtrace Viewer

A modern web application for viewing and analyzing backtrace files from sampling profilers, built with Svelte.

Features

• 📁 File Upload: Load your own backtrace files or use the included sample
• 🔍 Thread Filtering: Filter threads by name using exact prefix matching
• 👀 Toggle Views: Expand/collapse individual threads to focus on what matters
• 📊 Collapsible Backtraces: Click on any backtrace line to collapse/expand sections
• 📱 Responsive Design: Works great on desktop and mobile devices
• ⚡ Fast Performance: Built with Svelte for optimal performance

Getting Started

Prerequisites

• Node.js (version 14 or higher)
• npm or yarn

Installation

1. Clone or navigate to the project directory:

   cd backtrace-viewer
   

2. Install dependencies:

   npm install
   

3. Start the development server:

   npm run dev
   

4. Open your browser to http://localhost:5173

Building for Production

npm run build

The built files will be in the dist/ directory.

Usage

Loading Files

• The app will automatically load sample.txt when you open it
• Click "📁 Load Backtrace File" to upload your own backtrace files
• Supported format: Text files from sampling profilers (like macOS sample command)

Filtering Threads

• Use the filter input to find threads by name
• Only shows threads whose names start with your filter text (case-insensitive)
• Thread names are extracted from the part after the : in thread headers

Viewing Backtraces

• Click on any thread header to expand/collapse its backtrace
• Click on individual backtrace lines to collapse/expand sections
• Indentation shows the call hierarchy
• Sample counts and function names are highlighted for easy reading

File Format Support

The viewer supports backtrace files with this format:

6963 Thread_10032126: hf-xet-0
+ 6963 thread_start  (in libsystem_pthread.dylib) + 8  [0x19e40ab80]
+   6963 _pthread_start  (in libsystem_pthread.dylib) + 136  [0x19e40fc0c]
+     6963 pythread_wrapper  (in Python) + 48  [0x104da7cd0]
...

Where:

• Thread headers: {count} Thread_{id}: {name}
• Thread names: Optional part after :
• Backtrace lines: Indented with +, !, :, | characters
• Sample counts, function names, and addresses are automatically highlighted

Contributing

Feel free to open issues or submit pull requests to improve the viewer!

License

MIT License