Benchmark: Map vs Objects - MeasureThat.net

Script Preparation code:

var map = new Map();
var obj = Object.create(null);

map.set('a', 5);
obj['a'] = 5;

var i = 0, count = 1000, a;

Tests:

Map lookup
for (i = 0; i < count; i++) { a = map.get('a'); }
Obj lookup
for (i = 0; i < count; i++) { a = obj['a']; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Map lookup
Obj lookup

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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

LLMs can make mistakes. Check important info.

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

**Benchmark Overview**

The benchmark compares two approaches for looking up values in JavaScript objects: `Map` instances and regular objects (using the `Object.create(null)` method).

**Options Compared**

Two test cases are compared:

1. **Map Lookup**: This test case uses a `Map` instance to store the value `'a'` with key `'a'`. The benchmark measures how many times this lookup operation can be performed within 1000 iterations.
2. **Object Lookup**: This test case uses a regular object (created using `Object.create(null)`) to store the value `'a'` with key `'a'`. Again, the benchmark measures how many times this lookup operation can be performed within 1000 iterations.

**Pros and Cons of Each Approach**

1. **Map Lookup**:
	* Pros: Maps are optimized for fast lookups, especially when using keys that are not strings (e.g., numbers or symbols).
	* Cons: Maps require more memory than regular objects and have additional overhead due to the Map instance.
2. **Object Lookup**:
	* Pros: Regular objects are lightweight and don't require extra memory like Maps do.
	* Cons: Object lookups can be slower, especially for non-string keys, since they rely on the internal hash table.

**Library and Syntax Considerations**

The `Map` object is a built-in JavaScript library that provides an efficient way to store key-value pairs. Its purpose is to offer fast lookups by default.

There are no special JavaScript features or syntax used in this benchmark other than what's standard in modern JavaScript development.

**Other Alternatives**

If you're looking for alternative approaches, consider the following:

* Using a `Set` object instead of `Map` for fast membership testing (i.e., checking if a value exists).
* Utilizing libraries like Lodash or Ramda for functional programming and utility functions that might affect performance.
* Exploring other data structures, such as arrays or linked lists, for specific use cases.

Keep in mind that the choice of data structure ultimately depends on your application's requirements, size, and performance constraints.

Related benchmarks:

Map vs Objects (version: 0)

Lookup of map vs object

Comparing performance of: Map lookup vs Obj lookup

Created: 5 years ago by: Guest

Jump to the latest result

Map lookup

Obj lookup

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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