Benchmark: _concat vs _push vs _spread

Tests:

spread
let arr1 = (new Array(1000000)).fill("hello world"); arr1 = [...arr1, "hello world"]
push
let arr1 = (new Array(1000000)).fill("hello world"); arr1.push("hello world")
concat
let arr1 = (new Array(1000000)).fill("hello world"); arr1.concat("hello world");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
spread
push
concat

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/113.0.0.0 Safari/537.36

Browser/OS: Chrome 113 on Linux

View result in a separate tab

Test name	Executions per second
spread	67.1 Ops/sec
push	67.1 Ops/sec
concat	102.4 Ops/sec

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 JSON represents three test cases that compare the performance of different approaches for concatenating arrays in JavaScript:

1. `_concat` (using the `concat()` method)
2. `_push` (using the `push()` method)
3. `_spread` (using the spread operator `...`)

These test cases aim to measure which approach is the fastest and most efficient.

**Options compared:**

The three options being compared are:

1. **_concat**: Using the `concat()` method to concatenate an array with another value.
2. **_push**: Using the `push()` method to add a single element to the end of an array.
3. **_spread`: Using the spread operator `...` to create a new array by spreading the elements of an existing array and adding a new value.

**Pros and cons of each approach:**

1. **_concat_**:
	* Pros: Can be more intuitive for some developers, as it directly modifies the original array.
	* Cons: Creates a new array and can lead to unnecessary memory allocations.
2. **_push_**:
	* Pros: Efficiently adds an element to the end of an array without creating a new array.
	* Cons: Can be slower than `_concat` due to the overhead of pushing elements onto the array.
3. **_spread_**:
	* Pros: Creates a new array and can lead to less memory fragmentation compared to `_concat`.
	* Cons: May be less intuitive for some developers, as it requires understanding of spread operators.

**Library usage:**

None of the test cases use any external libraries, so there are no additional dependencies to consider.

**Special JS features or syntax:**

The spread operator `...` is used in the `_spread` test case. This feature was introduced in ECMAScript 2015 (ES6) and allows creating new arrays by spreading elements from an existing array.

**Other alternatives:**

While not explicitly mentioned, other approaches for concatenating arrays could be considered, such as:

1. Using `Array.prototype.push.apply()`
2. Creating a new array using the `Array.from()` method
3. Using a library like Lodash's `concat` function

However, these alternatives are not being tested in this specific benchmark.

**Benchmark preparation code:**

The script preparation code is empty, which means that no additional setup or initialization is required for each test case.

Related benchmarks:

_concat vs _push vs _spread (version: 0)

Comparing performance of: spread vs push vs concat

Created: one year ago by: Guest

Jump to the latest result

spread

push

concat

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):