Benchmark: Dynamic class vs object

Script Preparation code:

function newObj() {
  return {aaa: 42, bbb: "hello"}
}

function newClass() {
  return new class {
    aaa = 42
    bbb = "hello"
  }
}

class StaticClass {
  aaa = 42
  bbb = "hello"
}

window.StaticClass = StaticClass

Tests:

dynamic class
let obj = newClass() window.aaa = obj.aaa window.bbb = obj.bbb
object
let obj = newObj() window.aaa = obj.aaa window.bbb = obj.bbb
static class
let obj = new StaticClass() window.aaa = obj.aaa window.bbb = obj.bbb

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
dynamic class
object
static class

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36

Browser/OS: Chrome 130 on Windows

View result in a separate tab

Test name	Executions per second
dynamic class	527025.2 Ops/sec
object	3701650.2 Ops/sec
static class	3967411.2 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what's being tested.

**Benchmark Definition**

The benchmark is designed to compare the performance of three approaches:

1. **Dynamic Class**: A JavaScript class created using the `class` keyword, which will be instantiated as an object.
2. **Object**: An object created using a constructor function (`newObj`), which returns an object literal with properties `aaa` and `bbb`.
3. **Static Class**: A static class defined using the `class` keyword, but this time the class is not instantiated as an object.

The benchmark prepares a JavaScript script that:

* Defines two functions: `newClass()` and `newObj()`, which create instances of classes or objects, respectively.
* Assigns properties to these instances on the global scope (`window.aaa` and `window.bbb`).
* Measures the execution time for each test case.

**Options Compared**

The benchmark compares the performance of:

* Instantiating a dynamic class using `new class{...}` vs creating an object using `newObj()`.
* Creating a static class using `class{...}` vs assigning properties to an object created by `newObj()`.

**Pros and Cons of Each Approach**

1. **Dynamic Class**:
	* Pros: Can be more expressive and easier to read, as it follows the traditional class syntax.
	* Cons: May have performance overhead due to the overhead of creating a new scope for each instance.
2. **Object**:
	* Pros: Faster execution time, as no scope creation is involved.
	* Cons: Less readable and may not be as expressive as using classes.
3. **Static Class**:
	* Pros: Can be faster execution time, as the class is not instantiated as an object.
	* Cons: May be less readable and less maintainable than traditional classes.

**Library Used**

None in this specific benchmark.

**Special JS Feature or Syntax**

This benchmark uses JavaScript's `class` keyword to define dynamic and static classes. This feature was introduced in ECMAScript 2015 (ES6) and provides a more concise way to define classes.

**Other Considerations**

* The benchmark is running on Chrome 120, which may affect the results due to various factors like just-in-time compilation, caching, etc.
* The test cases are designed to be relatively simple and easy to understand, making it easier for users to compare and reproduce the results.

**Alternatives**

For those interested in exploring similar benchmarks, here are some alternatives:

1. **Benchmarking JavaScript classes**: A benchmark that compares the performance of different class creation methods (e.g., using `class` vs using a constructor function).
2. **JavaScript object creation benchmarks**: Benchmarks that compare the performance of creating objects using various methods (e.g., using literals, constructors, or classes).

Related benchmarks:

Dynamic class vs object (version: 0)

Comparing performance of: dynamic class vs object vs static class

Created: 2 years ago by: Registered User

Jump to the latest result

dynamic class

object

static class

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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