How Removing Caching Improved Mobile Performance by 25%
Article Summary
Klarna's team removed their caching layer and saw a 25% performance boost. Wait, what?
Case Taintor from Klarna Engineering set out to defer loading a fullscreen iframe to improve their checkout experience. Instead, his benchmarking revealed a hidden performance killer that had been lurking in production for years.
Key Takeaways
- Application cache was downloading duplicate assets while pages loaded normally
- Chrome's Network tab hides offline cache traffic entirely
- PhantomJS benchmarking with Docker revealed the hidden downloads
- Removing app cache cut Chrome Mobile load times by 25%
- HTTP caching headers already provided the performance they needed
Critical Insight
An optimization attempt uncovered that their application cache manifest was secretly downloading unnecessary assets, and removing it improved mobile performance by 25%.
