Benchmark: promise vs callback vs async

Tests:

async
async function getData() { return new Promise((resolve, reject) => { setTimeout(() => { const data = 'Some data'; resolve(data); }, 0); }); } async function main() { const data = await getData(); console.log(data); } main();
callback
function getData(callback) { setTimeout(() => { const data = 'Some data'; callback(data); }, 0); } getData((data) => { console.log(data); });
promise
function getData() { return new Promise((resolve, reject) => { setTimeout(() => { const data = 'Some data'; resolve(data); }, 0); }); } getData().then((data) => { console.log(data)})

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
async
callback
promise

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one month ago):

LLMs can make mistakes. Check important info.

Measuring JavaScript performance is crucial for ensuring optimal user experience and maintaining competitive edge. Let's break down the provided benchmarking scenario.

**Benchmarking Purpose:**
The test compares three approaches to handle asynchronous data retrieval in JavaScript:

1. **Callbacks**: Using callbacks, a function passed as an argument to another function, which is executed when the operation completes.
2. **Promises**: Promises are objects that represent the eventual completion (or failure) of an asynchronous operation. They provide a way to handle both success and error cases in a more elegant manner than callbacks.
3. **Async/Await**: This syntax allows for writing asynchronous code that looks and feels synchronous, using `async` functions and the `await` keyword.

**Comparison Options:**

*   **Callbacks**: This method uses a callback function as an argument to handle the result of an asynchronous operation.
    *   Pros:
        *   Lightweight, no additional dependencies required
        *   Can be easier to understand for developers familiar with traditional callbacks
    *   Cons:
        *   Can lead to "callback hell" (nested and tangled code), making it harder to read and maintain
        *   Limited support for error handling and promises
*   **Promises**: This method uses promise objects to handle asynchronous operations, providing a more modern and concise alternative to callbacks.
    *   Pros:
        *   More expressive and easier to read than callbacks
        *   Provides better support for error handling and chaining methods
        *   Easier to handle multiple asynchronous operations sequentially or concurrently
    *   Cons:
        *   Requires understanding of promise concepts and syntax
        *   May be slower due to the overhead of creating and managing promises
*   **Async/Await**: This method uses async functions with the await keyword to write asynchronous code that looks synchronous.
    *   Pros:
        *   Makes asynchronous code look and feel more synchronous, improving readability
        *   Easier to handle multiple asynchronous operations using for...of loops or async/await syntax
    *   Cons:
        *   Limited support in older browsers (e.g., Safari 8-10.1)
        *   May not be suitable for all use cases where callbacks or promises are more suitable

**Test Cases:**
Each test case provides a specific implementation of the three approaches:

*   **Callback**: `getData` function takes a callback as an argument and uses `setTimeout` to simulate an asynchronous operation.
    *   Library/Dependency: None
*   **Promise**: Similar to the callback example, but using promises to handle the result instead.
    *   Library/Dependency: Built-in JavaScript Promise API
*   **Async/Await**: Asynchronous function `main` uses async/await syntax to wait for the completion of the `getData` promise and log the result.

**Alternative Approaches:**
Other alternatives include:

*   **Closures**: Using closure-based callbacks can simplify callback code by encapsulating data and behavior within a single scope.
*   **Libraries like RxJS or Bluebird**: These libraries provide more advanced features for working with promises, such as mapping, filtering, and combining operations.

**Considerations:**
When choosing between these approaches, consider the following factors:

*   Performance requirements
*   Code readability and maintainability
*   Compatibility across different browsers and platforms
*   Use of additional dependencies or libraries

By understanding the strengths and weaknesses of each approach, developers can make informed decisions when designing asynchronous code in JavaScript.

Latest run results:

Run details: (Test run date: 9 months ago)

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 16_1_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.1 Mobile/15E148 Safari/604.1

Browser/OS: Mobile Safari 16 on iOS 16.1.1

View result in a separate tab

Test name	Executions per second
async	450800.5 Ops/sec
callback	1529838.9 Ops/sec
promise	1009545.0 Ops/sec

Related benchmarks:

promise vs callback vs async (version: 0)

Comparing performance of: async vs callback vs promise

Created: 9 months ago by: Guest

Jump to the latest result

async

callback

promise

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one month ago):