Benchmark: just another for loop performance 2

Script Preparation code:

var array = new Array(100000).fill(Math.random())

Tests:

cached
let tmp = []; let k = array.length; for (let i = 0; i < k; i++) { tmp.push(array[i]+i); }; console.log(tmp)
uncached
let tmp = []; for (let i = 0; i < array.length; i++) { tmp.push(array[i] + i); }; console.log(tmp);
forEach
let tmp = []; let i = 0; array.forEach(x => { tmp.push(x + i); i++; }); console.log(tmp);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
cached
uncached
forEach

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4379.0 Safari/537.36

Browser/OS: Chrome 89 on Windows

View result in a separate tab

Test name	Executions per second
cached	106.2 Ops/sec
uncached	62.8 Ops/sec
forEach	354.7 Ops/sec

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

LLMs can make mistakes. Check important info.

The provided JSON represents a benchmark test created on MeasureThat.net, a website that allows users to create and run JavaScript microbenchmarks. The benchmark tests the performance of different approaches to iterate over an array.

**Benchmark Definition:**
The benchmark definition is a simple script that pushes elements from an array into another array, with or without caching. There are three test cases:

1. "cached": This approach uses caching by storing the length of the array in a variable `k` before the loop, and then using this value to iterate over the array.
2. "uncached": This approach does not use caching and iterates over the array directly using its length property.
3. "forEach": This approach uses the `forEach()` method of the array to iterate over it.

**Options Compared:**

The benchmark compares the performance of three different approaches:

* Caching (using a variable to store the array's length)
* Uncached iteration (iterating over the array using its length property)
* Using the `forEach()` method

Each approach has its pros and cons:

* **Caching (cached)**:
	+ Pros: Can be faster for large arrays since it avoids repeated lookups of the array's length.
	+ Cons: Requires an additional variable to store the length, which can add overhead.
* **Uncached iteration**:
	+ Pros: Simple and does not require any additional variables.
	+ Cons: May be slower due to repeated lookups of the array's length.
* **Using `forEach()` (forEach)**:
	+ Pros: Can be faster since it avoids manual looping and indexing.
	+ Cons: Requires an additional method call, which can add overhead.

**Other Considerations:**

When interpreting these results, consider the size of the array being tested. For large arrays, caching is likely to provide a performance boost due to reduced lookups. However, for small arrays or in situations where memory is limited, the simplicity of uncached iteration may be more desirable.

**JavaScript Features Used:**

None are explicitly mentioned, but JavaScript's `forEach()` method and variable declarations (e.g., `let`, `var`) are used throughout the benchmark.

**Alternative Approaches:**
Other approaches to iterating over an array could include:

* Manual indexing using `array[index]`
* Using a loop with `array[i++]` or `for (let i = 0; i < array.length; i++)`
* Using `array.map()` and chaining methods
* Using `slice()` and looping

Keep in mind that each approach has its own trade-offs, and the best choice depends on the specific requirements of your use case.

Related benchmarks:

just another for loop performance 2 (version: 0)

cached vs uncached

Comparing performance of: cached vs uncached vs forEach

Created: 2 years ago by: Guest

Jump to the latest result

cached

uncached

forEach

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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