Benchmark: javascript rulettaa

Tests:

for loop
const items = Array.from({ length: 100000 }, (_, index) => index); for (let i = 0; i < items.length; i++) { const result = items[i] * 2; }
forEach
const items = Array.from({ length: 100000 }, (_, index) => index); items.forEach((item) => { const result = item * 2; });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for loop
forEach

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks.

**What is being tested?**

The provided benchmark measures the performance difference between two approaches to iterate over an array of numbers: using a traditional `for` loop and using the `forEach` method.

In the benchmark definition, we see two test cases:

1. **For Loop**: The script iterates over the array using a traditional `for` loop, where the index is calculated manually.
```javascript
const items = Array.from({ length: 100000 }, (_, index) => index);
for (let i = 0; i < items.length; i++) {
  const result = items[i] * 2;
}
```
2. **ForEach**: The script uses the `forEach` method to iterate over the array, without manually calculating the index.
```javascript
const items = Array.from({ length: 100000 }, (_, index) => index);
items.forEach((item) => {
  const result = item * 2;
});
```
**Options compared**

The benchmark compares the performance of two approaches:

1. **For Loop**: This approach uses a traditional `for` loop to iterate over the array.
	* Pros:
		+ Simple and easy to understand.
		+ Can be optimized for performance by using techniques like caching or memoization.
	* Cons:
		+ Requires manual index calculation, which can lead to errors if not done correctly.
2. **ForEach**: This approach uses the `forEach` method to iterate over the array.
	* Pros:
		+ Easy to use and understand, as it's a built-in method in JavaScript.
		+ Eliminates the need for manual index calculation.
	* Cons:
		+ May be slower than traditional loops due to overhead from the `forEach` method.

**Other considerations**

When choosing between these two approaches, consider the following factors:

1. **Readability**: If readability is more important than performance, `forEach` might be a better choice due to its simplicity and ease of use.
2. **Performance**: If performance is critical, traditional loops like `for` loops might be faster due to reduced overhead from built-in methods.

**Library usage**

Neither of the test cases uses any external libraries, so no additional dependencies are involved in this benchmark.

**Special JS features or syntax**

There are no special JavaScript features or syntax used in these benchmarks. They rely on standard JavaScript language and built-in functions like `Array.from` and `forEach`.

**Alternatives**

Other alternatives for iterating over arrays include:

1. **Map**: Instead of using `forEach`, you can use the `map` method to create a new array with transformed values.
```javascript
const items = Array.from({ length: 100000 }, (_, index) => index);
const mappedItems = items.map((item) => item * 2);
```
2. **Reduce**: You can also use the `reduce` method to iterate over arrays and accumulate values.
```javascript
const items = Array.from({ length: 100000 }, (_, index) => index);
const result = items.reduce((acc, item) => acc + item * 2, 0);
```
Keep in mind that these alternatives might have different performance characteristics compared to traditional loops or `forEach` methods.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
for loop	357.6 Ops/sec
forEach	297.6 Ops/sec

Related benchmarks:

javascript rulettaa (version: 0)

Comparing performance of: for loop vs forEach

Created: one year ago by: Guest

Jump to the latest result

for loop

forEach

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):