Performancemedium
How does useEffect impact performance in React applications?
Discuss the role of the useEffect hook in functional components and how improper usage can lead to performance issues.
Answer
• useEffect runs after every render by default, which can lead to unnecessary calculations and re-renders. • Specify dependencies to control its execution - empty array means it runs only once (componentDidMount). • Use cleanup functions to avoid memory leaks when components unmount. • Overusing useEffect with heavy computations or incorrect dependencies can degrade performance.