Benchmark: filter vs splice

Script Preparation code:

window.test = [
  { id: 1, source: true },
  { id: 2, source: true },
  { id: 3, source: false }
]

Tests:

filter
window.test.filter(function (item) { return item.source === false })
array splice
window.test.splice(2, 1)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
filter
array splice

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's dive into the provided benchmark definition and test cases.

**Overview of the Benchmark**

The benchmark compares two approaches: filtering an array using the `Array.prototype.filter()` method versus removing elements from the array using the `Array.prototype.splice()` method.

**Options Compared**

The benchmark tests two options:

1. **Filtering**: The `filter()` method creates a new array with all elements that pass the test implemented by the provided function.
2. **Splicing**: The `splice()` method removes elements from the array and returns an updated array.

**Pros and Cons of Each Approach**

**Filtering (Array.prototype.filter())**

Pros:

* More concise and readable code
* Does not modify the original array
* Can be more efficient for large arrays, as it only creates a new array with the filtered elements

Cons:

* Creates a new array, which can lead to increased memory usage
* May have performance implications if the filtering function is complex or slow

**Splicing (Array.prototype.splice())**

Pros:

* Modifies the original array, reducing memory usage
* Can be faster than filtering for small arrays or when elements need to be removed quickly

Cons:

* Changes the original array, which may not be desirable in some cases
* Can lead to performance issues if elements are frequently inserted or deleted from the array

**Other Considerations**

The benchmark also considers the use of a library (in this case, none is explicitly mentioned) and does not test any special JavaScript features or syntax.

**Library: None**

There is no explicit mention of any libraries being used in the benchmark code. However, it's worth noting that some browsers may optimize certain methods more efficiently than others due to specific implementation details in their respective JavaScript engines.

**Special JavaScript Features/Syntax: None**

There are no special JavaScript features or syntax being tested in this benchmark.

**Alternatives**

Some alternatives to consider when deciding between filtering and splicing include:

* Using `Array.prototype.map()` with a negative length argument to create an empty array, which can be equivalent to filtering.
* Using `Array.prototype.slice()` with a start index and end index to extract elements from the original array, which can be more efficient than splicing for large arrays.
* Using native WebAssembly (WASM) or other low-level languages for performance-critical parts of your code.

In conclusion, the choice between filtering and splicing depends on the specific requirements of your use case. If you need to modify the original array and prioritize memory usage, splicing may be a better option. However, if you can tolerate creating a new array and prioritize readability and maintainability, filtering is likely a better choice.

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 11_2_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.192 Safari/537.36

Browser/OS: Chrome 88 on Mac OS X 11.2.2

View result in a separate tab

Test name	Executions per second
filter	3948082.8 Ops/sec
array splice	3773715.0 Ops/sec

Related benchmarks:

filter vs splice (version: 0)

Comparing performance of: filter vs array splice

Created: 4 years ago by: Guest

Jump to the latest result

filter

array splice

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):