Benchmark: forEach vs for i loop addition

Script Preparation code:

var values = [30310, 100303, 3040494]

Tests:

Array.forEach
var count = 0; values.forEach(function(v,i) { count += v; })
native
var count = 0; for (var i = 0; i < values.length; i++) { count += values[i]; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.forEach
native

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

**What is being tested?**

The provided JSON represents a benchmark test case that compares two approaches to adding up values in an array: using `Array.prototype.forEach` and a native loop (`for...of` loop or traditional `for` loop).

**Options compared:**

* **`Array.prototype.forEach`**: This method iterates over the elements of an array, executing a callback function for each element. In this case, the callback function adds up the values using `count += v;`.
* **Native Loop (`for...of` or traditional `for` loop)**: A traditional `for` loop is used to iterate over the array, while a `for...of` loop (introduced in ECMAScript 2015) can also be used for the same purpose.

**Pros and Cons of each approach:**

* **`Array.prototype.forEach`**:
	+ Pros:
		- Easier to read and maintain, as it's a higher-level abstraction.
		- Reduces the likelihood of off-by-one errors or index out-of-bounds issues.
	+ Cons:
		- May be slower due to the overhead of function invocation and iteration.
* **Native Loop (`for...of` or traditional `for` loop)**:
	+ Pros:
		- Typically faster, as it avoids the overhead of function invocation and iteration.
		- More control over iteration variables and loop conditions.
	+ Cons:
		- Requires more boilerplate code to set up and manage the loop.
		- Risk of errors due to off-by-one issues or index out-of-bounds problems.

**Library usage:**

There is no explicit library used in this benchmark test case. However, it's worth noting that `Array.prototype.forEach` relies on the built-in array methods and prototypes.

**Special JS feature/syntax:**

There is a special syntax used in this benchmark:

* **ECMAScript 2015 (`for...of` loop)**: This loop type was introduced in ECMAScript 2015 as a more modern alternative to traditional `for` loops. It provides a safer and more efficient way to iterate over arrays.

**Benchmark preparation code:**

The provided script preparation code is:
```javascript
var values = [30310, 100303, 3040494];
```
This initializes an array `values` with three elements, which will be used as the input for both the `Array.prototype.forEach` and native loop implementations.

**Individual test cases:**

The benchmark consists of two individual test cases:

* **`Array.prototype.forEach`**: This test case uses the `forEach` method to iterate over the `values` array.
* **Native Loop (`for...of` or traditional `for` loop)**: This test case uses a traditional `for` loop (or an equivalent `for...of` loop) to iterate over the `values` array.

**Other alternatives:**

There are other ways to add up values in an array, such as:

* Using `Array.prototype.reduce()`
* Using `Array.prototype.map()` and then iterating over the result
* Using a recursive function

However, these alternatives may have different performance characteristics or use more memory resources compared to the native loop approach.

Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/75.0.3770.142 Safari/537.36

Browser/OS: Chrome 75 on Windows

View result in a separate tab

Test name	Executions per second
Array.forEach	7602519.0 Ops/sec
native	1568135.0 Ops/sec

Related benchmarks:

forEach vs for i loop addition (version: 0)

Comparing performance of: Array.forEach vs native

Created: 5 years ago by: Guest

Jump to the latest result

Array.forEach

native

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):