Benchmark: Promise vs async vs callbacks

Tests:

Callback
((next) => {next()})(() => {});
Promise
new Promise((resolve) => { resolve(true)});
Async
(async() => { await true; })();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Callback
Promise
Async

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:153.0) Gecko/20100101 Firefox/153.0

Browser/OS: Firefox 153 on Windows

View result in a separate tab

Callback

509.0M/s

Promise

2.5M/s

Async

699K/s

View exact numbers

Test name	Executions per second
✓ Callback	508,974,848 Ops/sec
Promise	2,502,276 Ops/sec
Async	699,139 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested.

**What is being tested?**

The benchmark compares three different approaches for handling asynchronous operations in JavaScript:

1. **Callbacks**: A callback function is a function passed as an argument to another function, which is then executed when the outer function completes.
2. **Promises**: Promises are objects that represent the eventual completion (or failure) of an operation and its result.
3. **Async/await**: Async/await is a syntax feature introduced in modern JavaScript that allows for asynchronous programming with a synchronous API.

**Options compared**

The benchmark compares the performance of each approach:

* Callback: The callback function is called immediately, without waiting for the outer function to complete.
* Promise: A promise is created and resolved with the result. The `await` keyword is used to wait for the resolution.
* Async/await: The async function is executed, and the `await` keyword is used to wait for the resolution of the promises.

**Pros and Cons**

Here's a brief overview of each approach:

* **Callbacks**: Pros:
	+ Lightweight, no additional memory allocation required.
	+ Easy to implement in older JavaScript versions.
Cons:
	+ Can lead to callback hell (nested callbacks), making code harder to read and maintain.
	+ Error handling can be cumbersome.
* **Promises**: Pros:
	+ Easier to handle errors and chain multiple operations.
	+ More expressive than callbacks, with a clear "either/then" structure.
Cons:
	+ Can lead to memory leaks if not properly cleaned up.
	+ Less intuitive for beginners.
* **Async/await**: Pros:
	+ Simplifies asynchronous programming with a synchronous API.
	+ Easy to read and maintain code.
Cons:
	+ Requires modern JavaScript versions (ES6+).
	+ Can be slower due to the overhead of creating and managing promises.

**Library and special JS feature**

There is no specific library being used in this benchmark, other than the built-in JavaScript features mentioned above.

**Special JS feature**

The `await` keyword is a special JavaScript feature introduced in modern JavaScript versions (ES6+). It allows for asynchronous programming with a synchronous API, making it easier to write and read code that handles asynchronous operations.

**Other alternatives**

If async/await is not supported by the browser, developers can use callbacks or promises as an alternative. However, if they want to take advantage of the concise syntax and expressive nature of async/await, they may need to opt for a different approach, such as using Web Workers for parallel execution.

In summary, the benchmark compares three approaches for handling asynchronous operations in JavaScript: callbacks, promises, and async/await. Each approach has its pros and cons, and the choice depends on the specific use case, performance requirements, and personal preference.

Promise vs async vs callbacks (version: 0) Benchmark.js

Promise vs async vs callbacks

Comparing performance of: `Callback vs Promise vs Async`

Created: 3 years ago by: Guest

Go to the latest result

Callback

Promise

Async

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Promise vs async vs callbacks (version: 0) Benchmark.js

Promise vs async vs callbacks

Comparing performance of: Callback vs Promise vs Async

Created: 3 years ago by: Guest

Go to the latest result

Callback

Promise

Async

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

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Comparing performance of: `Callback vs Promise vs Async`