A performance profiling component for react -> https://www.telerik.com/blogs/profiling-react-components-with-the-user-timing-api

MeasureRender.jsx

class MeasureRender extends React.Component {
  constructor() {
    super();
    this.mounted = false;
  }

  render() {
    const { name } = this.props;
    if (this.mounted) {
      window.performance.mark(`${name}UpdateStart`);
    } else {
      window.performance.mark(`${name}MountStart`);
    }
    return this.props.children;
  }

  componentDidMount() {
    const { name } = this.props;
    this.mounted = true;
    window.performance.mark(`${name}MountEnd`);
    window.performance.measure(`${name}Mount`, `${name}MountStart`, `${name}MountEnd`);
  }

  componentDidUpdate() {
    const { name } = this.props;
    window.performance.mark(`${name}UpdateEnd`);
    window.performance.measure(`${name}Update`, `${name}UpdateStart`, `${name}UpdateEnd`);
  }
}