Virtual DOM, Fiber, and Reconciliation

Virtual DOM:

  • Imagine a lightweight, in-memory copy of the actual DOM tree in your React application. This is the virtual DOM.

  • It's a JavaScript representation of the UI, reflecting the current state of your components.

  • React keeps this virtual DOM up-to-date whenever there's a change in your application's state.

Reconciliation:

  • This is the process where React compares the previous virtual DOM with the new one created after a state change.

  • Reconciliation involves a clever diffing algorithm that efficiently identifies the minimal changes required in the real DOM.

  • This avoids the cost of blindly re-rendering the entire DOM for every state update, leading to smoother performance.

Fiber:

  • Introduced in React 16, Fiber is a new reconciliation engine that significantly improves performance, especially for complex UIs with a lot of animations or interactions.

  • Unlike the previous reconciliation approach, Fiber allows for:

    • Incremental rendering: React can break down the rendering work into smaller chunks and spread it out over multiple browser frames, resulting in smoother animations.

    • Priority scheduling: React can prioritize urgent updates (like user interactions) over lower priority ones, ensuring a more responsive user experience.

/Read more...

github.com/acdlite/react-fiber-architecture