Benchmark: React 18.2 useCallback hook vs. function

HTML Preparation code:

<!doctype html>
<html>
  <head>
    <title>This is the title of the webpage!</title>
  </head>
  <body>
  	<script src="https://cdnjs.cloudflare.com/ajax/libs/react/18.2.0/umd/react.production.min.js"></script>
	<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/18.2.0/umd/react-dom.production.min.js"></script>
	<div id="root"></div> 
  </body>
</html>

Script Preparation code:

function ComponentWithOuterFunctionUseCallback() {
  function functionToTest(evt) {
	evt.preventDefault();
  }
  const testFunction = React.useCallback(functionToTest, []);
  return React.createElement('button', {onClick: testFunction}, 'Test click');
}

function ComponentWithUseCallback() {
  const testFunction = React.useCallback(evt => evt.preventDefault(), []);
  return React.createElement('button', {onClick: testFunction}, 'Test click');
}

function ComponentWithInlineFunction() {
  function testFunction(evt) {
    evt.preventDefault();
  }
  return React.createElement('button', {onClick: testFunction}, 'Test click');
}

function ComponentWithArrowFunction() {
  const testFunction = (evt) => {
    evt.preventDefault();
  }
  return React.createElement('button', {onClick: testFunction}, 'Test click');
}

var root = ReactDOM.createRoot(document.getElementById('root'));

Tests:

ComponentWithUseCallback
root.render(React.createElement(ComponentWithUseCallback))
ComponentWithInlineFunction
root.render(React.createElement(ComponentWithInlineFunction))
ComponentWithArrowFunction
root.render(React.createElement(ComponentWithArrowFunction))
ComponentWithOuterFunctionUseCallback
root.render(React.createElement(ComponentWithOuterFunctionUseCallback))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
ComponentWithUseCallback
ComponentWithInlineFunction
ComponentWithArrowFunction
ComponentWithOuterFunctionUseCallback

Fastest: N/A

Slowest: N/A

Autogenerated LLM Sumamry (model llama3.2:3b, generated 3 days ago):

LLMs can make mistakes. Check important info.

I'll break down the benchmark test and explain what's being compared, pros and cons of each approach, and other considerations.

**Benchmark Test Overview**

The provided benchmark test compares four different ways to implement a click event handler in React hooks:

1. `ComponentWithUseCallback`: uses the `React.useCallback` hook to memoize the function.
2. `ComponentWithInlineFunction`: defines the function directly inside the component.
3. `ComponentWithArrowFunction`: uses an arrow function to define the callback.
4. `ComponentWithOuterFunctionUseCallback`: wraps the callback in a separate outer function.

**What's being compared**

The test compares the execution speed of these four approaches on different browsers and devices. The goal is to determine which approach performs best in terms of execution speed.

**Options Compared**

1. **`React.useCallback`**: This hook memoizes a function so that it's only recreated when its dependencies change. It helps prevent unnecessary re-renders.
2. **Inline functions**: Defining the function directly inside the component can be faster because there's no overhead of creating an external function reference.
3. **Arrow functions**: Arrow functions are shorthand for defining functions and don't create a new scope, making them potentially faster.
4. **Outer function wrapping**: Wrapping the callback in an outer function might introduce additional overhead due to the creation of a new scope.

**Pros and Cons**

1. **`React.useCallback`**:
	* Pros: Memoization helps prevent unnecessary re-renders, reducing the number of computations.
	* Cons: Might introduce additional overhead for creating and updating the memoized function reference.
2. **Inline functions**:
	* Pros: Fastest execution speed due to minimal overhead.
	* Cons: Can lead to tight coupling between components and harder debugging.
3. **Arrow functions**:
	* Pros: Concise and easy to read, with potential for faster execution due to the absence of a new scope.
	* Cons: Limited understanding among developers without experience with arrow functions.
4. **Outer function wrapping**:
	* Pros: Easy to understand and maintain, as it clearly separates the callback from the component's logic.
	* Cons: Introduces additional overhead for creating an external function reference.

**Other Considerations**

* The test uses a specific version of React (18.2) and Chrome browser, which might affect results due to updates or bug fixes in newer versions.
* The benchmark only tests execution speed on desktop devices; results may vary on mobile devices or other platforms.

**Alternatives**

If you're considering alternative approaches for implementing click event handlers in React hooks:

1. **Use `React.useCallback` with a more complex dependency array**: If the callback depends on multiple variables, using `React.useCallback` can help reduce unnecessary re-renders.
2. **Explore other optimization techniques**, such as memoization or caching of function calls, to further improve performance.

Keep in mind that the best approach will depend on your specific use case and performance requirements.

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/118.0.0.0 Safari/537.36

Browser/OS: Chrome 118 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
ComponentWithUseCallback	1372876.0 Ops/sec
ComponentWithInlineFunction	1395984.0 Ops/sec
ComponentWithArrowFunction	1367609.0 Ops/sec
ComponentWithOuterFunctionUseCallback	1340264.0 Ops/sec

Related benchmarks:

React 18.2 useCallback hook vs. function (version: 0)

Comparing performance of: ComponentWithUseCallback vs ComponentWithInlineFunction vs ComponentWithArrowFunction vs ComponentWithOuterFunctionUseCallback

Created: one year ago by: Guest

Jump to the latest result

ComponentWithUseCallback

ComponentWithInlineFunction

ComponentWithArrowFunction

ComponentWithOuterFunctionUseCallback

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Sumamry (model llama3.2:3b, generated 3 days ago):