What performance testing tools are available in React world, and how to start using them?
You can use React Developer Tools to get a quick overview of what components re-render. Enable option "Highlight updates when components render".
Not all renders are equal. Some are less performant than others. Don't try to fix every unnecessary render. Instead, find bottlenecks and fix them. React Developer Tools Profiler tab will help you with this.
Often, web app performance issues are not related to React. Analytics tracking libraries, excessive CSS animations, non-optimized images, iframes, and many more factors can contribute to poor performance. You can use the Chrome DevTools Performance tab to debug these issues.
Originally published at alexsidorenko.com