Benchmark: Push vs Concat - MeasureThat.net

Tests:

Push 1
var arr = [1, 2, 3, 4, 5]; arr.push.apply(arr, [6])
Concat 1
var arr = [1, 2, 3, 4, 5]; arr = arr.concat([6])
Push 5
var arr = [1, 2, 3, 4, 5]; arr.push.apply(arr, new Array(5).fill(0))
Concat 5
var arr = [1, 2, 3, 4, 5]; arr.concat(new Array(5).fill(0))
Push 10
var arr = [1, 2, 3, 4, 5]; arr.push.apply(arr, new Array(10).fill(0))
Concat 10
var arr = [1, 2, 3, 4, 5]; arr.concat(new Array(10).fill(0))
Push 20
var arr = [1, 2, 3, 4, 5]; arr.push.apply(arr, new Array(20).fill(0))
Concat 20
var arr = [1, 2, 3, 4, 5]; arr.concat(new Array(20).fill(0))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Push 1
Concat 1
Push 5
Concat 5
Push 10
Concat 10
Push 20
Concat 20

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.

**Benchmark Definition**

The benchmark definition is simply a JSON object that contains the code for a specific test case. In this case, we have two approaches to add an array to an existing array: using `push.apply()` and using `concat()`. The script preparation code and HTML preparation code are empty, which means that the browser's JavaScript engine will handle these operations.

**Options Compared**

We're comparing the performance of two approaches:

1. **`push.apply()`**: This method uses the `apply()` method to call the `push()` method on an array with multiple arguments.
2. **`concat()`**: This method creates a new array by concatenating another array.

**Pros and Cons of Each Approach**

* **`push.apply()`**:
	+ Pros: More explicit, can be faster in some cases due to tail call optimization (not applicable here since we're using `apply()`, but still).
	+ Cons: Can lead to slower performance if the `push()` method is optimized to avoid unnecessary copies.
* **`concat()`**:
	+ Pros: Creates a new array, which can be faster in some cases due to better caching and locality of reference.
	+ Cons: Can lead to slower performance if the resulting array is large and needs to be allocated.

**Library Usage**

There doesn't seem to be any explicit library usage in these benchmark definitions. However, it's worth noting that MeasureThat.net likely uses a framework or library under the hood to execute the JavaScript code and measure its performance.

**Special JS Features/Syntax**

None of the test cases use special JavaScript features or syntax beyond what is standard for modern JavaScript engines (ECMAScript 2015+).

**Alternatives**

If you want to explore alternative approaches, here are some options:

1. **`Array.prototype.push()`**: This method pushes an element onto the end of the array and returns the new length of the array.
2. **`Set()`**: A modern JavaScript data structure that can be used to add elements to an array without modifying its original order.
3. **`Array.from()`**: A method that creates a new array from an iterable or an array-like object.

Keep in mind that these alternatives might not have the same performance characteristics as `push.apply()` and `concat()`, depending on the specific use case and browser/ engine implementation.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/105.0.0.0 Safari/537.36

Browser/OS: Chrome 105 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Push 1	71623264.0 Ops/sec
Concat 1	15710045.0 Ops/sec
Push 5	7569335.5 Ops/sec
Concat 5	5780464.0 Ops/sec
Push 10	6964827.5 Ops/sec
Concat 10	5629826.0 Ops/sec
Push 20	6002567.0 Ops/sec
Concat 20	5282841.0 Ops/sec

Related benchmarks:

Push vs Concat (version: 3)

Comparing performance of: Push 1 vs Concat 1 vs Push 5 vs Concat 5 vs Push 10 vs Concat 10 vs Push 20 vs Concat 20

Created: 7 years ago by: Registered User

Jump to the latest result

Push 1

Concat 1

Push 5

Concat 5

Push 10

Concat 10

Push 20

Concat 20

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):