Benchmark: set delete vs array splice

Script Preparation code:

var arr = [...Array(1000).keys()]
var set = new Set(arr)

Tests:

set delete
set.delete(1)
arr
arr.splice(arr.indexOf(1), 1)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
set delete
arr

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

**Overview**

MeasureThat.net is a website that allows users to create and run JavaScript microbenchmarks to compare the performance of different approaches. In this explanation, we'll break down what's being tested in the provided benchmark definition JSON, describe the options compared, their pros and cons, and discuss other considerations.

**Benchmark Definition**

The benchmark definition consists of two parts:

1. **Script Preparation Code**: This code is executed before running each test case.
```javascript
var arr = [...Array(1000).keys()];
var set = new Set(arr);
```
This code creates an array `arr` with 1000 elements and a `Set` object `set` from the array.

2. **Html Preparation Code**: This field is empty, indicating that no additional HTML setup is required for this benchmark.

**Individual Test Cases**

The benchmark defines two test cases:

1. **set.delete(1)**:
This test case calls the `delete()` method on a `Set` object with an argument of 1.
2. **arr.splice(arr.indexOf(1), 1)**:
This test case calls the `splice()` method on the original array `arr` using the index of 1 and removing one element.

**Options Compared**

These two test cases compare the performance of deleting an element from a `Set` object versus removing an element from an array using `splice()`. The primary difference is that `delete()` modifies the set in-place, whereas `splice()` returns a new array with the element removed.

**Pros and Cons**

* **Delete()**:
	+ Pros: In-place modification, potentially faster since it doesn't create a new array.
	+ Cons: May not be as intuitive for developers familiar with arrays, and can lead to unexpected behavior if used incorrectly.
* **Splice()**:
	+ Pros: More intuitive for developers familiar with arrays, allows for easier handling of edge cases.
	+ Cons: Creates a new array, potentially slower due to memory allocation.

**Other Considerations**

* Both test cases assume that the `Set` object and array are large enough to benefit from deleting or removing an element. For smaller sets or arrays, the performance difference may be negligible.
* The benchmark doesn't account for other operations that might affect performance, such as iterating over the set or array after deletion.

**Alternative Approaches**

Other approaches could be tested in this benchmark, such as:

* Using `Array.prototype.filter()` to remove an element from the array
* Creating a new array using `Array.from()` and removing an element from it
* Using `Map` instead of `Set` for storing unique values

However, these alternatives would likely introduce additional complexity and may not be relevant for this specific benchmark.

**Library: Set**

The `Set` object is a built-in JavaScript object that stores unique values. Its primary purpose is to provide fast membership testing (i.e., checking if an element exists in the set) and efficient insertion and deletion of elements. In this benchmark, the `Set` object is used to store unique keys from the array and allow for efficient deletion.

**Special JS Feature/Syntax**

There are no special JavaScript features or syntax mentioned in this benchmark definition. The code uses standard JavaScript concepts and operations.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36

Browser/OS: Chrome 126 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
set delete	24728400.0 Ops/sec
arr	12798921.0 Ops/sec

Related benchmarks:

set delete vs array splice (version: 0)

Comparing performance of: set delete vs arr

Created: 11 months ago by: Registered User

Jump to the latest result

set delete

arr

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):