Benchmark: Map vs Object - Write

Script Preparation code:

var map = new Map();
var obj = {};

var i = 0, count = 1000;

Tests:

Map write
for (i = 0; i < count; i++) { map.set(i+'', i); }
Obj write
for (i = 0; i < count; i++) { obj[i+''] = i; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Map write
Obj write

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Mobile Safari/537.36

Browser/OS: Chrome Mobile 123 on Android

View result in a separate tab

Test name	Executions per second
Map write	752.7 Ops/sec
Obj write	766.8 Ops/sec

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, compared, and their pros and cons.

**Benchmark Overview**

The benchmark compares the performance of two data structures in JavaScript: Maps (a built-in JavaScript object that stores key-value pairs) and plain objects (also known as hash tables or dictionaries). The goal is to measure how efficiently each structure can write (insert) 1,000 key-value pairs.

**Options Compared**

There are only two options being compared:

1. **Map Write**: Using a Map to store the key-value pairs.
2. **Object Write**: Using a plain object to store the key-value pairs.

**Pros and Cons of Each Approach**

**Map Write:**

Pros:

* Maps provide efficient lookups, insertions, and deletions using their built-in `set()` method, which can lead to better performance in certain scenarios.
* Map objects are dynamic, meaning they can handle changes without requiring explicit updates.

Cons:

* Maps require an additional overhead for storing the keys (using integers) compared to plain objects.
* Map operations might be slower due to the need to store and retrieve the key-value pairs from a hash table.

**Object Write:**

Pros:

* Plain objects are lightweight, with no additional overhead for storing keys.
* Object operations like property assignment (`obj[key] = value`) can be faster since they don't require a separate data structure for storing keys.

Cons:

* Objects do not provide built-in support for efficient lookups, insertions, or deletions, requiring manual implementation using methods like `obj[key] = value` or object iteration.
* Objects may incur additional overhead due to the need to store and retrieve property values from an array.

**Library Used**

None is explicitly mentioned in the benchmark definition. However, both Map and Object implementations rely on JavaScript's built-in data structures and objects.

**Special JS Features/Syntax**

There are no special JavaScript features or syntax being used in this benchmark. It only relies on standard JavaScript syntax for defining variables (e.g., `var map = new Map();`), loops (`for` loop), and assignment operations (`map.set()`).

**Other Alternatives**

In theory, other data structures like arrays, sets, or even custom-built hash tables could be used instead of Maps and objects. However, in JavaScript, these alternatives might not provide the same level of efficiency or convenience as using the built-in Map and Object implementations.

Keep in mind that this benchmark is designed to test the performance of writing key-value pairs into a data structure, which can have implications for various use cases like caching, data storage, or high-performance applications.

Related benchmarks:

Map vs Object - Write (version: 0)

Write of map vs object

Comparing performance of: Map write vs Obj write

Created: 3 years ago by: Guest

Jump to the latest result

Map write

Obj write

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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