Benchmark: Map vs Object Longer

Script Preparation code:

var map = new Map();
var obj = {};

map.set('a', 5);
map.set('b', 5);
map.set('c', 5);
map.set('d', 5);
map.set('e', 5);

obj['a'] = 5;
obj['b'] = 5;
obj['c'] = 5;
obj['d'] = 5;
obj['e'] = 5;

var i = 0, count = 1000, a;

Tests:

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

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

This benchmark does not have any results yet. Be the first one to run it!

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 is being tested, compared options, pros and cons of those approaches, and other considerations.

**Benchmark Overview**

The provided benchmark compares the performance of two data structures in JavaScript: Maps and objects. Both data structures are used to store key-value pairs, but they differ in how keys are stored and accessed.

**Script Preparation Code**

The script preparation code creates an instance of a Map (`map`) and an object (`obj`), both initialized with the same key-value pairs:
```javascript
var map = new Map();
var obj = {};

map.set('a', 5);
map.set('b', 5);
map.set('c', 5);
map.set('d', 5);
map.set('e', 5);

obj['a'] = 5;
obj['b'] = 5;
obj['c'] = 5;
obj['d'] = 5;
obj['e'] = 5;
```
**Html Preparation Code**

There is no HTML preparation code provided, which means the benchmark only focuses on JavaScript performance.

**Individual Test Cases**

The benchmark consists of two individual test cases:

1. **Map Lookup**: This test case iterates `count` times, accessing each key in the map using the `get()` method:
```javascript
for (i = 0; i < count; i++) {
  a = map.get('a');
  a = map.get('b');
  a = map.get('c');
  a = map.get('d');
  a = map.get('e');
}
```
2. **Object Lookup**: This test case is similar to the previous one, but it accesses keys in the object using bracket notation (`[]`):
```javascript
for (i = 0; i < count; i++) {
  a = obj['a'];
  a = obj['b'];
  a = obj['c'];
  a = obj['d'];
  a = obj['e'];
}
```
**Comparison**

The benchmark compares the performance of these two test cases, which essentially boil down to:

* Accessing keys in a Map using `get()`.
* Accessing keys in an object using bracket notation (`[]`).

**Pros and Cons of Each Approach**

1. **Map Lookup (get())**
	* Pros:
		+ More efficient for large datasets since maps use a hash table under the hood.
		+ Supports fast lookup, insertion, and deletion operations.
	* Cons:
		+ May require more memory since each key-value pair is stored as a separate entity in the map.
2. **Object Lookup ([])**
	* Pros:
		+ More lightweight since objects use a hash table-like structure internally for keys.
		+ Supports fast lookup, insertion, and deletion operations.
	* Cons:
		+ May not be as efficient for very large datasets since each key-value pair is stored sequentially.

**Library Used**

No specific JavaScript library is used in this benchmark. However, both `Map` and objects use built-in JavaScript data structures and methods.

**Special JS Features or Syntax**

There are no special JavaScript features or syntax used in this benchmark. The code uses standard JavaScript data types (Maps, objects) and basic iteration constructs (`for` loops).

**Other Considerations**

* The benchmark only focuses on performance, not security, readability, or maintainability.
* The `count` variable determines the number of iterations performed by each test case.
* The `executionsPerSecond` metric provides a measure of each test case's performance in terms of the number of executions per second.

**Alternatives**

Other data structures and libraries that can be used for similar benchmarking purposes include:

* Arrays
* Sets
* WeakMaps (for garbage collection considerations)
* Libraries like Lodash or Ramda, which provide alternative data structure implementations or utility functions.

Related benchmarks:

Map vs Object Longer (version: 0)

Lookup of map vs object

Comparing performance of: Map lookup vs Obj lookup

Created: 3 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):