React performance best practices include using the react-addons-perf module to measure wasted renders, avoiding direct state/prop mutations, ensuring connected components only re-render when needed, and using immutability to prevent unnecessary re-renders when data changes. Potential issues are components re-rendering even when props haven't changed, large portions of the tree re-rendering unnecessarily, and binding functions incorrectly.

1.
React perf
import Perf from 'react-addons-perf';
window.perf = Perf;
Perf.start();
ReactDOM.render(<app/>, document.getElementById('react-root'));
Perf.stop();
Perf.printWasted();

2. When component
updates
when internal state changes
when new props are coming (parent's render
method must be triggered)
component does not check if new props are
di erent
when forceUpdate() method is triggered

3. What can possibly go
wrong?
state/props mutation
non-speci c connect
large parts of the tree not changing but
rerendering
binding the function in the wrong place

11. What can help
?react-perf
react-addons-perf
immutability libraries (like Immutable.js)