Benchmark: Class method / instance method / bind this – more closer to reality test

Script Preparation code:

window.A = class {
    a() {}
}

window.AReady = new A();

window.B = class {
    b = () => {};
}

window.BReady = new B();

window.C = class {
    constructor() {
        this.c = this.c.bind(this);
    }

    c() {}
}

window.CReady = new C();

Tests:

Call class method
new A();
Call instance method
new B();
Call bound method
new C();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Call class method
Call instance method
Call bound method

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 23 days ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:132.0) Gecko/20100101 Firefox/132.0

Browser/OS: Firefox 132 on Linux

View result in a separate tab

Test name	Executions per second
Call class method	1243444736.0 Ops/sec
Call instance method	44239164.0 Ops/sec
Call bound method	34974988.0 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated 23 days ago):

LLMs can make mistakes. Check important info.

The benchmark represented in the provided JSON tests the performance of different approaches to defining and calling methods in JavaScript classes. Specifically, it compares three different strategies: class methods, instance methods, and bound methods. Each approach has its own characteristics, advantages, and disadvantages.

### Description of Each Comparison

1. **Call Class Method (`new A();`)**
   - **Definition**: This test case uses a class `A` with a standard class method `a()`. This method is called on an instance of class `A`.
   - **Performance**: This approach shows the highest number of executions per second (approximately 1.24 billion).
   - **Pros**:
     - Simple and straightforward syntax.
     - Methods are defined on the class's prototype, which can lead to better memory usage if many instances are created, as they share the same method references.
   - **Cons**:
     - May not always reflect real-life usage where method context and binding are significant.

2. **Call Instance Method (`new B();`)**
   - **Definition**: In this case, class `B` has a method defined as an instance property using an arrow function. This means the method is tied to the instance of the class when it is created.
   - **Performance**: This method shows a significantly lower number of executions per second (about 44 million).
   - **Pros**:
     - Arrow functions automatically bind the context of `this`, making it easier to maintain the desired context without additional binding.
   - **Cons**:
     - Methods are created for each instance, which can lead to higher memory usage if many instances are created; each instance has its own copy of the function.
     - Results in slower performance compared to prototype methods.

3. **Call Bound Method (`new C();`)**
   - **Definition**: Class `C` contains a standard method `c()` which is manually bound to `this` in the constructor via the `.bind()` method.
   - **Performance**: This approach has the lowest performance of the three (around 34 million).
   - **Pros**:
     - Allows for explicit binding of `this`, ensuring the method always has the correct context when invoked.
   - **Cons**:
     - Binding functions can incur a performance penalty and may lead to increased memory usage due to the creation of bound function instances.
     - Slightly more verbose setup compared to the other methods.

### Other Considerations

- **Real-World Scenarios**: When choosing a method definition style in JavaScript, considerations depend on how methods will be invoked, whether they're passed as callbacks, and the importance of `this` context. Class methods might be more beneficial in scenarios with many instances sharing behaviors, whereas bound methods and instance properties may be preferable in scenarios where specific context management is necessary.
  
- **Library Use**: The test does not involve external libraries; it strictly uses built-in JavaScript features for defining classes and methods.

- **JavaScript Features/Syntax**: The benchmark uses ES6 class syntax, which provides a cleaner and more intuitive way to create objects and handle inheritance compared to the older prototype-based approach. Arrow functions (`() => {}`) are also used in this benchmark to ensure context is lexically bound.

### Alternatives

Several alternatives exist for method definition in JavaScript, including:

- **Functional Programming**: Using standalone functions or higher-order functions to handle methods could be a more functional programming approach.
- **Mixins and Composition**: Instead of inheritance through class definitions, using mixins or functional composition to share behavior and properties can be considered.
- **Prototypal Inheritance**: The traditional way of defining methods on an object's prototype for better memory efficiency.
- **Method Decoupling**: Defining methods outside of classes or using modules to encapsulate behavior without relying on class structure.

In conclusion, the choice of method definition has significant effects on performance and memory, and developers should balance these factors with the readability, maintainability, and the specific use case requirements in their applications.

Related benchmarks:

Class method / instance method / bind this – more closer to reality test (version: 1)

Comparing performance of: Call class method vs Call instance method vs Call bound method

Created: 23 days ago by: Guest

Jump to the latest result

Call class method

Call instance method

Call bound method

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated 23 days ago):