Benchmark: useCallback vs without

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/16.13.1/umd/react.production.min.js"></script>
	<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.13.1/umd/react-dom.production.min.js"></script>
	<div id="root"></div> 
  </body>
</html>

Script Preparation code:

function ComponentWithUseCallback() {
  const testFunction = React.useCallback(evt => evt.preventDefault(), []);
  return React.createElement('button', {onClick: testFunction}, 'Test click');
}


function ComponentWithoutUseCallback() {
  const testFunction = evt => evt.preventDefault();
  return React.createElement('button', {onClick: testFunction}, 'Test click');
}

Tests:

without
ReactDOM.render(React.createElement(ComponentWithUseCallback), document.getElementById('root'))
usecallback
ReactDOM.render(React.createElement(ComponentWithoutUseCallback), document.getElementById('root'))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
without
usecallback

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated 3 days ago):

LLMs can make mistakes. Check important info.

The benchmark compares two approaches to handling event handlers in React components: using `React.useCallback` versus defining the event handler as a regular function.

### Options Compared

1. **ComponentWithUseCallback**:
   - Event Handler: The `testFunction` is created using `React.useCallback`, which memoizes the function based on its dependencies (in this case, there are none, as indicated by the empty array `[]`).
   - Purpose: The `useCallback` hook helps in preventing unnecessary re-creations of the function each time the component re-renders. This can be beneficial in cases where the component has multiple renders, and the function gets passed down to child components that may rely on reference equality (to prevent unnecessary re-renders).

2. **ComponentWithoutUseCallback**:
   - Event Handler: The `testFunction` is defined as a regular function inside the component, meaning a new instance of this function is created on every render.
   - Purpose: This approach is more straightforward and simpler, but it can lead to performance issues in larger applications, especially if the function is passed down to child components that use `React.memo` or similar optimizations, as the component can re-render when the function reference changes.

### Benchmark Results

Based on the results of the benchmark:
- **Without useCallback**: Executions per second: **1,110,103.625**
- **With useCallback**: Executions per second: **866,933.8125**

### Pros and Cons

#### Pros of using `React.useCallback`:
- Reduces unnecessary re-creation of functions on every render, potentially improving performance in components that have expensive rendering logic or in deeply nested child trees.
- Helps prevent re-renders of memoized child components when the function is passed down as a prop.

#### Cons of using `React.useCallback`:
- Adds a small overhead to manage its dependencies. If not used correctly, it can lead to bugs (if dependencies are missing) or performance degradation (where the memory overhead outweighs benefits in relatively simple components).
- For components with few renders or simple logic, the overhead of `useCallback` might be unnecessary.

#### Using Regular Functions:
- Simplicity of implementation without memorization overhead.
- Clear and readable code for simpler components.

### Libraries Involved
- **React**: A JavaScript library for building user interfaces. It allows developers to create reusable UI components and manage state and lifecycle through hooks (like `useCallback`).

### Other Considerations
- For components that don’t rely on memoization or that don’t pass functions to memoized children, using standard function declarations may be preferable.
- The differences in performance may not be significant in smaller applications or in cases with few renders. However, in larger applications or performance-critical components, the trade-offs between these two approaches become more apparent.

### Alternatives
- Developers can also consider using `React.memo` alongside regular functions, which can provide performance boosts without the need for `useCallback`.
- If function re-instantiation is a concern, alternatives like using a stable reference stored in a state or context can also be explored, although they might complicate state management.

In summary, this benchmark evaluates how different approaches to managing event handlers within React components can affect performance, particularly in scenarios where rerenders occur frequently. The choice between `useCallback` and a standard function declaration largely depends on the specific use case and the complexity of the components being used.

Latest run results:

Run details: (Test run date: 3 days ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
without	1110103.6 Ops/sec
usecallback	866933.8 Ops/sec

Related benchmarks:

useCallback vs without (version: 1)

Comparing performance of: without vs usecallback

Created: 3 days ago by: Guest

Jump to the latest result

without

usecallback

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated 3 days ago):