Run results for: useMemo and memo

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.93 Safari/537.36

Browser: Chrome 90

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
No Memo	3953.0 Ops/sec
UseMemoAndOptimizedChild	4988.9 Ops/sec
UseMemoAlone	4323.7 Ops/sec

HTML Preparation code:

<div id="root"></div>

<script src="https://unpkg.com/react@16/umd/react.development.js"></script>
<script src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script>
<script src="https://cdn.jsdelivr.net/npm/lodash@4.17.15/lodash.min.js"></script>

Script Preparation code:

function ChildComponent(props) {
  return React.createElement("div", props);
}

const OptimizedChildComponent = React.memo(ChildComponent);

function UseMemoAndOptimizedChild(props) {
  const handler = React.useMemo(() => {
      return _.debounce(props.handler, props.wait);
  }, [props.handler, props.wait]);
  return React.createElement(OptimizedChildComponent, { className: handler() });
}

function UseMemoAlone(props) {
  const handler = React.useMemo(() => {
      return _.debounce(props.handler, props.wait);
  }, [props.handler, props.wait]);
  return React.createElement(ChildComponent, { className: handler() });
}

function NoMemo(props) {
  const handler = _.debounce(props.handler, props.wait);
  return React.createElement(ChildComponent, { className: handler() });
}

var propCases = [{
  handler: function() { return Math.random(); },
  wait: 100
}, {
  handler: function() { return Math.random(); },
  wait: 200
}];
propCases.push(propCases[1]);

Tests:

No Memo
propCases.forEach((props) => { ReactDOM.render(React.createElement(NoMemo, props, null), root); });
UseMemoAndOptimizedChild
propCases.forEach((props) => { ReactDOM.render(React.createElement(UseMemoAndOptimizedChild, props, null), root); });
UseMemoAlone
propCases.forEach((props) => { ReactDOM.render(React.createElement(UseMemoAlone, props, null), root); });

Run results for: useMemo and memo

No Memo

UseMemoAndOptimizedChild

UseMemoAlone