Benchmark: `a += b` vs `a = a + b`

Script Preparation code:

let a = 2;
let b = 2;

Tests:

a += b
let a = 2; let b = 2; a += b;
a = a + b
let a = 2; let b = 2; a = a + b;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
a += b
a = a + b

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (Linux; Android 10; ONEPLUS A5000) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/84.0.4147.125 Mobile Safari/537.36

Browser/OS: Chrome Mobile 84 on Android

View result in a separate tab

Test name	Executions per second
a += b	437525472.0 Ops/sec
a = a + b	440096704.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark definition and test cases to explain what's being tested.

**Benchmark Definition**

The benchmark measures the performance difference between two ways of adding values to a variable `a`:

1. **Incremental assignment**: `a += b`
2. **Assignment with addition**: `a = a + b`

The benchmark tests which approach is faster in terms of executions per second on various browsers and devices.

**Options Compared**

Two options are being compared:

1. Incremental assignment (`a += b`)
2. Assignment with addition (`a = a + b`)

**Pros and Cons**

- **Incremental assignment (`a += b`)**
	+ Pros:
		- Often more efficient in terms of memory usage, as it avoids creating a temporary variable.
		- Can be faster due to the compiler or interpreter's ability to optimize the code.
	+ Cons:
		- May not work correctly if `b` is negative, resulting in unexpected results.
- **Assignment with addition (`a = a + b`)**
	+ Pros:
		- Always produces correct results, regardless of the value of `b`.
	+ Cons:
		- Typically less efficient due to the creation of a temporary variable.

**Library and Purpose**

None of the test cases use any specific JavaScript library. The benchmark is focused on testing the performance difference between two basic syntaxes in JavaScript.

**Special JS Feature or Syntax**

There are no special JavaScript features or syntaxes being tested in this benchmark.

**Other Considerations**

When writing benchmarks, it's essential to consider factors such as:

* Hardware and software compatibility
* Browser and device support
* Optimizations for different environments (e.g., mobile vs. desktop)
* Code readability and maintainability

**Alternatives**

Some alternatives to MeasureThat.net include:

1. **jsbench**: A web-based benchmarking platform specifically designed for JavaScript.
2. **Benchmark.js**: A lightweight, modular benchmarking library for Node.js applications.
3. **Benchmark-Tools**: A collection of benchmarking tools for various programming languages, including JavaScript.

These alternatives offer different features, such as support for multi-threading, GPU acceleration, and more comprehensive reporting.

Related benchmarks:

`a += b` vs `a = a + b` (version: 0)

Comparing `a += b` vs `a = a + b`

Comparing performance of: a += b vs a = a + b

Created: 4 years ago by: Registered User

Jump to the latest result

a += b

a = a + b

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):