Benchmark: Stor info in Array vs Object

Script Preparation code:

function makeid(length) {
    var result           = '';
    var characters       = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
    var charactersLength = characters.length;
    for ( var i = 0; i < length; i++ ) {
      result += characters.charAt(Math.floor(Math.random() * 
 charactersLength));
   }
   return result;
}


var values = Array.from({length: 1000}).map(()=> makeid(10));

Tests:

Array index
let a = []; for(let i = 0; i < values.length; i++) a[i] = values[i];
Object
let b = {}; for(let i = 0; i < values.length; i++) b[values[i]] = values[i];
Array.push
let c = []; for(let i = 0; i < values.length; i++) c.push(values[i]);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array index
Object
Array.push

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.82 Safari/537.36

Browser/OS: Chrome 89 on Linux

View result in a separate tab

Test name	Executions per second
Array index	6392.2 Ops/sec
Object	3136.9 Ops/sec
Array.push	5795.9 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark and explain what's being tested, compared, and their pros and cons.

**Benchmark Definition**

The benchmark is designed to compare three approaches for storing information in JavaScript:

1. **Array**: Storing values in an array using `values[i]`.
2. **Object**: Storing values as keys in an object using `b[values[i]] = values[i]`.
3. **Array.push**: Storing values in an array using the `push` method.

**Options Compared**

The benchmark compares the performance of these three approaches for storing information in JavaScript. The key factors being measured are:

* **Memory allocation**: How much memory is allocated by each approach?
* **Execution time**: How long does it take to execute each approach?

**Pros and Cons of Each Approach**

1. **Array**:
	* Pros: Simple, efficient, and widely supported.
	* Cons: Not suitable for large amounts of data, as arrays have a fixed size.
2. **Object**:
	* Pros: Suitable for large amounts of data, as objects can grow dynamically. Also, provides faster lookups than array indices.
	* Cons: Requires more memory allocation, and some older browsers may not support it properly.
3. **Array.push**:
	* Pros: Efficient for adding new elements to the end of an array.
	* Cons: Not suitable for storing large amounts of data in a single array.

**Library Used**

In this benchmark, no external libraries are used.

**Special JS Feature or Syntax**

There is no special JavaScript feature or syntax being tested in this benchmark. It only involves basic language features like arrays and objects.

**Benchmark Preparation Code**

The script preparation code generates an array of 1000 random strings (each 10 characters long) using the `makeid` function, which is not a standard JavaScript function. This allows the benchmark to test performance with large datasets.

**Individual Test Cases**

There are three test cases:

1. **Array index**: Tests storing values in an array using `values[i]`.
2. **Object**: Tests storing values as keys in an object using `b[values[i]] = values[i]`.
3. **Array.push**: Tests adding new elements to the end of an array using `c.push(values[i])`.

**Latest Benchmark Result**

The latest benchmark result shows the performance metrics for each test case:

| TestName | ExecutionsPerSecond |
| --- | --- |
| Array index | 6392.154296875 |
| Array.push | 5795.93310546875 |
| Object | 3136.933349609375 |

These results indicate that:

* Storing values in an array using `values[i]` is the fastest approach.
* Adding new elements to an array using `push` is faster than storing values as keys in an object.

Keep in mind that these results are specific to this benchmark and may not be representative of real-world performance.

Related benchmarks:

Stor info in Array vs Object (version: 0)

Comparing performance of: Array index vs Object vs Array.push

Created: 3 years ago by: Guest

Jump to the latest result

Array index

Object

Array.push

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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