WhySoSlow

WhySoSlow: Lightweight Performance Profiling Tool

Identify bottlenecks in web applications, track server response times, queries, and resources with WhySoSlow, a lightweight performance profiling tool.

What is WhySoSlow?

WhySoSlow is a lightweight web application performance profiler designed to help developers diagnose issues that impact site speed. It works by tracking server response times for pages and assets, capturing slow database queries, gathering key metrics like memory usage and load, and mapping out the relationships between resources to identify bottlenecks.

Once installed, WhySoSlow starts profiling sites automatically without code changes. It captures comprehensive performance data on the fly and presents it through an intuitive UI so developers can slice and dice by pages, URLs, referrers, and more to see where optimization is needed. Custom reporting and annotations allow drilling down to log what code changes may have caused performance regressions.

Key features include:

• Server response time tracking for pages and assets
• Slow query capturing for multiple databases
• Code profiling to identify heavy functions
• Memory and load reporting
• Waterfall diagrams mapping resource relationships
• Trend graphs for historical comparison
• Custom annotations and reporting

WhySoSlow integrates with all major frameworks like Django, Rails, Laravel, and any web stack. It's optimized for minimal overhead so it can run on production without impacting end users. The dashboard gives developers a 30,000 foot view of application performance from a single pane of glass.

WhySoSlow Features

Official Links