Benchmark: slice VS splice VS shift: who is the fastest to keep constant size 2

Script Preparation code:

var list = [];
for (var i = 0; i < 1000 * 1000; i++) {
  list.push(i);
}

Tests:

slice
list.push('slice'); list = list.slice(0, 1000 * 1000 / 2);
splice
list.push('splice'); list.splice(0, 1000 * 1000 / 2);
shift
list.push('shift'); for (var i = 0; i < 1000 * 1000 / 2; i++) { list.shift(); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
slice
splice
shift

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):

LLMs can make mistakes. Check important info.

I'd be happy to explain the benchmark and its various aspects.

**Benchmark Overview**

The benchmark is designed to compare the performance of three JavaScript methods: `slice()`, `splice()`, and `shift()`. These methods are used to manipulate arrays in JavaScript. The goal of this benchmark is to determine which method is the fastest when keeping a constant size 2 for a large array.

**Script Preparation Code**

The script preparation code is provided as:
```javascript
var list = [];
for (var i = 0; i < 1000 * 1000; i++) {
  list.push(i);
}
```
This code creates an empty array `list` and then populates it with 1 million elements using a loop. The purpose of this code is to create a large array that will be used for the benchmark.

**Html Preparation Code**

There is no Html preparation code provided, which means that the benchmark does not include any HTML-related overhead or distractions.

**Individual Test Cases**

The individual test cases are defined as:
```javascript
[
  {
    "Benchmark Definition": "list.push('slice');\r\nlist = list.slice(0, 1000 * 1000 / 2);",
    "Test Name": "slice"
  },
  {
    "Benchmark Definition": "list.push('splice');\r\nlist.splice(0, 1000 * 1000 / 2);",
    "Test Name": "splice"
  },
  {
    "Benchmark Definition": "list.push('shift');\r\nfor (var i = 0; i < 1000 * 1000 / 2; i++) {\r\n  list.shift();\r\n}",
    "Test Name": "shift"
  }
]
```
These test cases define three different scenarios:

1. `slice()`: Pushes an element onto the array and then uses `slice()` to create a new array containing only half of the original elements.
2. `splice()`: Pushes an element onto the array and then uses `splice()` to remove half of the original elements from the beginning of the array.
3. `shift()`: Pushes an element onto the array and then repeatedly removes elements from the beginning of the array using `shift()`.

**Library**

There is no explicit library mentioned in the benchmark, but it's likely that the benchmark is using the built-in JavaScript methods `slice()` and `splice()` which are part of the ECMAScript standard.

**Special JS Feature or Syntax**

There is no special JS feature or syntax used in this benchmark. The code uses only basic JavaScript constructs such as arrays, loops, and method calls.

**Other Alternatives**

If you were to rewrite this benchmark using alternative methods, here are a few options:

* Use a different data structure, such as a linked list or a tree, instead of an array.
* Use a different algorithm for manipulating the array elements, such as sorting or filtering.
* Add additional overhead, such as parsing HTML or executing DOM manipulation code.
* Compare performance using a different metric, such as memory usage or CPU cycles.

Keep in mind that these alternatives may change the nature of the benchmark and potentially introduce new biases or complexities.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.0.3 Safari/605.1.15

Browser/OS: Safari 14 on Mac OS X 10.15.6

View result in a separate tab

Test name	Executions per second
slice	392.6 Ops/sec
splice	3851626.8 Ops/sec
shift	21.4 Ops/sec

Related benchmarks:

slice VS splice VS shift: who is the fastest to keep constant size 2 (version: 0)

100k list

Comparing performance of: slice vs splice vs shift

Created: 3 years ago by: Guest

Jump to the latest result

slice

splice

shift

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 25 days ago):