Benchmark: JavaScript Map vs. Object instantiation

Script Preparation code:

var iterations = 100000;

Tests:

Object instantiation
for (let i = 0; i < iterations; i++) { const result = new Map(); }
Map instantiation
for (let i = 0; i < iterations; i++) { const result = { }; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object instantiation
Map instantiation

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36

Browser/OS: Chrome 135 on Linux

View result in a separate tab

Test name	Executions per second
Object instantiation	1253.3 Ops/sec
Map instantiation	16106.6 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the explanation of what is tested on the provided JSON.

**Benchmark Definition**

The benchmark measures the performance difference between instantiating a `Map` and an object (`{}`) in JavaScript. A `Map` is a data structure that stores key-value pairs, whereas an object is used to store multiple values with associated keys.

**Options Compared**

Two options are compared:

1. **Object Instantiation**: This option creates an empty object (`{}`) using the `new` keyword.
2. **Map Instantiation**: This option creates a new `Map` instance using the `new` keyword.

**Pros and Cons of Each Approach**

**Object Instantiation:**

Pros:

* Simple to create, as it only requires the `new` keyword.
* Easy to understand and implement.

Cons:

* May not provide optimal performance due to overhead from object creation.

**Map Instantiation:**

Pros:

* Can take advantage of optimized map implementation under the hood.
* May be faster for large datasets or complex data structures.

Cons:

* Requires a deeper understanding of JavaScript's internal data structures.

**Other Considerations**

When using `Map` instances, it's essential to note that they are ordered by their keys. This can have implications for certain algorithms and data processing workflows.

**Library Usage**

In the provided JSON, there is no explicit library usage mentioned. However, some browsers (like Firefox) may utilize internal libraries or engines that optimize map performance.

**Special JS Feature/Syntax**

This benchmark does not require any special JavaScript features or syntax. The focus is solely on comparing object instantiation and map instantiation.

**Alternatives**

Other alternatives for benchmarking JavaScript data structure creation include:

1. **Array Instantiation**: Creating an empty array using the `new` keyword.
2. **Set Instantiation**: Creating a new set instance using the `new` keyword.
3. **Data Structure-Specific Benchmarks**: Depending on the use case, benchmarks might focus on more specific data structures like binary trees or graph data structures.

These alternatives can provide additional insights into performance characteristics of different JavaScript data structures and libraries.

In summary, this benchmark provides a basic comparison between object instantiation and map instantiation in JavaScript, highlighting potential performance differences between these two approaches.

Related benchmarks:

JavaScript Map vs. Object instantiation (version: 0)

Comparing performance of: Object instantiation vs Map instantiation

Created: 3 years ago by: Guest

Jump to the latest result

Object instantiation

Map instantiation

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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