Benchmark: push vs create new and assign 2.0

Script Preparation code:

var x = Array(10).fill(0).map((_,i) => i);

Tests:

push
for(let i = 0; i < 10; i++) { x.push(i*11); }
create new and assign
for(let i = 0; i < 10; i++) { x = [...x, i*11]; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
push
create new and assign

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 29 days ago):

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark definition, test cases, and results for you.

**Benchmark Definition**

The benchmark is called "push vs create new and assign 2.0". This suggests that the comparison being made is between two different approaches to achieve the same result:

1. **Push**: Using the `push` method to add elements to an array.
2. **Create new and assign**: Creating a new array by spreading an existing array using the spread operator (`[...x, ...]`) and then assigning it to a variable.

**Script Preparation Code**

The script preparation code is:
```javascript
var x = Array(10).fill(0).map((_, i) => i);
```
This line creates an array `x` with 10 elements, where each element is the index `i`. This array will be used as a common reference for both test cases.

**Html Preparation Code**

There is no HTML preparation code provided.

**Individual Test Cases**

There are two individual test cases:

1. **Push**
```javascript
for (let i = 0; i < 10; i++) {
  x.push(i * 11);
}
```
This test case uses the `push` method to add 10 elements to array `x`, where each element is calculated as `i * 11`. The goal of this test case is to measure the performance of using the `push` method.

2. **Create new and assign**
```javascript
for (let i = 0; i < 10; i++) {
  x = [...x, i * 11];
}
```
This test case creates a new array by spreading an existing array `x` using the spread operator (`[...x]`) and then adding 10 elements to it. The goal of this test case is to measure the performance of creating a new array using the spread operator.

**Pros and Cons**

Here are some pros and cons of each approach:

1. **Push**
	* Pros:
		+ Efficient use of memory, as no new array needs to be allocated.
		+ Fast iteration over the array.
	* Cons:
		+ May cause performance issues if the array is very large, due to the overhead of adding elements to the end of the array.
2. **Create new and assign**
	* Pros:
		+ Can be faster for large arrays, as it avoids the overhead of adding elements to the end of an array.
	* Cons:
		+ Allocates a new array, which can lead to memory issues if not handled properly.
		+ May be slower due to the additional iteration over the array.

**Libraries and Special JS Features**

There are no libraries mentioned in the benchmark definition. However, the use of the spread operator (`[...x]`) is a modern JavaScript feature introduced in ECMAScript 2015 (ES6).

**Other Alternatives**

Some other alternatives to consider:

* **Array.prototype.concat()**: This method concatenates two or more arrays and returns a new array. It can be used instead of `push` to add elements to an array.
* **Array.prototype.push.apply()**: This method applies the `push` method to an array, allowing for efficient addition of multiple elements.

Keep in mind that these alternatives may have different performance characteristics compared to the original test cases.

I hope this explanation helps you understand the benchmark definition and its various components!

Latest run results:

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

User agent: Mozilla/5.0 (Linux; Android 4.4.2; M8) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.93 Mobile Safari/537.36

Browser/OS: Chrome Mobile 79 on Android 4.4.2

View result in a separate tab

Test name	Executions per second
push	82085.5 Ops/sec
create new and assign	0.4 Ops/sec

Related benchmarks:

push vs create new and assign 2.0 (version: 0)

Comparing performance of: push vs create new and assign

Created: 4 years ago by: Guest

Jump to the latest result

push

create new and assign

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 29 days ago):