Benchmark: Map vs Property Accessor

Script Preparation code:

var HEROES = [
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
  ["Tony", "Stark", 35, "Iron Man", ["Avengers"]],
  ["Peter", "Parker", 20, "Spiderman", ["Avengers"]],
  ["Steve", "Rogers", 80, "Captain America", ["Howling Commandos", "Avengers"]],
  ["Jessica", "Jones", 33, "Jewel", ["Defenders", "Avengers"]],
  ["Luke", "Cage", 34, "Power Man", ["Defenders", "Avengers"]],
];
class Superhero {
  #name;
  #lastName;
  #age;
  #alterEgo;
  #teams;

  constructor(name, lastName, age, alterEgo, teams) {
    this.#name = name;
    this.#lastName = lastName;
    this.#age = age;
    this.#alterEgo = alterEgo;
    this.#teams = teams;
  }

  get name() {
    return this.#name;
  }
  get lastName() {
    return this.#lastName;
  }
  get age() {
    return this.#age;
  }
  get alterEgo() {
    return this.#alterEgo;
  }
  get teams() {
    return this.#teams;
  }

  toObject() {
    return {
      age: this.age,
      alterEgo: this.alterEgo,
      lastName: this.lastName,
      name: this.name,
      teams: this.teams,
    };
  }
}

class SuperheroWithMap {
  #props = new Map();

  constructor(name, lastName, age, alterEgo, teams) {
    this.#props.set("name", name);
    this.#props.set("lastName", lastName);
    this.#props.set("age", age);
    this.#props.set("alterEgo", alterEgo);
    this.#props.set("teams", teams);
  }

  #getProp(key) {
    return this.#props.get(key);
  }

  getName = this.#getProp.bind(this, "name");
  getLastName = this.#getProp.bind(this, "lastName");
  getAge = this.#getProp.bind(this, "age");
  getAlterEgo = this.#getProp.bind(this, "alterEgo");
  getTeams = this.#getProp.bind(this, "teams");

  toObject() {
    return {
      age: this.getAge(),
      alterEgo: this.getAlterEgo(),
      lastName: this.getLastName(),
      name: this.getName(),
      teams: this.getTeams(),
    };
  }
}

function createSuperhero(props) {
  return new Superhero(...props);
}

function createSuperheroWithMap(props) {
  return new SuperheroWithMap(...props);
}

Tests:

Class with Getters
HEROES.map(createSuperhero).map((hero) => hero.toObject());
Class with Props in Map
HEROES.map(createSuperheroWithMap).map((hero) => hero.toObject());

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Class with Getters
Class with Props in Map

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

A challenging benchmarking scenario!

After analyzing the provided code and test cases, I'll provide an answer to your question.

**Question:** Which class, `Superhero` or `SuperheroWithMap`, is more efficient when it comes to serializing objects to JavaScript objects using `toObject()`?

**Answer:**

According to the benchmark results, the `Class with Getters` test case shows a significant performance difference between the two classes. The Chrome 93 browser executes the test at approximately 5720 executions per second.

In contrast, the `Class with Props in Map` test case has much slower execution times, with Chrome 93 executing at around 2085 executions per second.

This suggests that the `SuperheroWithMap` class is less efficient than the `Superhero` class when it comes to serializing objects to JavaScript objects using `toObject()`.

The main reason for this difference lies in how the classes handle property access and serialization. The `Superhero` class uses getter methods, which are more efficient and straightforward to implement. On the other hand, the `SuperheroWithMap` class relies on a Map data structure, which introduces additional overhead when accessing properties.

To improve performance, you can consider modifying the `SuperheroWithMap` class to use a similar approach to the `Superhero` class, such as using getter methods or storing properties in an object literal. Alternatively, you can optimize the `toObject()` method of the `SuperheroWithMap` class to reduce overhead when serializing objects.

**Code suggestions:**

To improve performance, consider modifying the `SuperheroWithMap` class to use a similar approach to the `Superhero` class:
```javascript
class SuperheroWithMap {
  #props = {};

constructor(props) {
    this.#props.name = props.name;
    this.#props.lastName = props.lastName;
    this.#props.age = props.age;
    this.#props.alterEgo = props.alterEgo;
    this.#props.teams = props.teams;
  }

get name() { return this.#props.name; }
  get lastName() { return this.#props.lastName; }
  get age() { return this.#props.age; }
  get alterEgo() { return this.#props.alterEgo; }
  get teams() { return this.#props.teams; }

toObject() {
    return {
      name: this.name,
      lastName: this.lastName,
      age: this.age,
      alterEgo: this.alterEgo,
      teams: this.teams,
    };
  }
}
```
By using getter methods and an object literal, you can reduce overhead when serializing objects.

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/93.0.4577.99 Safari/537.36

Browser/OS: Chrome 93 on Windows 7

View result in a separate tab

Test name	Executions per second
Class with Getters	5720.9 Ops/sec
Class with Props in Map	2085.5 Ops/sec

Related benchmarks:

Map vs Property Accessor (version: 0)

Comparing performance of: Class with Getters vs Class with Props in Map

Created: 2 years ago by: Registered User

Jump to the latest result

Class with Getters

Class with Props in Map

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):