Benchmark: Map vs Object 10k iterations

Script Preparation code:

var map = new Map();
var obj = {};

map.set('a', 5);
obj['a'] = 5;

var i = 0, count = 10000, 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

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Autogenerated LLM Summary (model gemma2:9b, generated one year ago):

LLMs can make mistakes. Check important info.

This benchmark compares the performance of accessing values from JavaScript Maps versus traditional objects.

Here's a breakdown:

**Options Compared:**

* **`map.get('a')`:**  Uses the `.get()` method on a `Map` object to retrieve the value associated with the key 'a'. Maps are designed for efficient key-value storage and retrieval, especially when dealing with large datasets or unique keys.
* **`obj['a']`:** Accesses the value associated with the key 'a' using bracket notation on a standard JavaScript object. Objects use a dictionary-like structure where keys can be strings, numbers, or symbols.

**Pros and Cons:**

| Approach | Pros                                         | Cons                                          |
|----------|----------------------------------------------|-----------------------------------------------|
| **Map**   | - Efficient for large datasets.              | - Slightly more complex syntax initially.     |
| **Object**| - Familiar syntax for most JavaScript developers.  | - Can be slower than Maps, especially with large datasets. |

**Other Considerations:**

* **Key Type:** Maps support any data type as a key (strings, numbers, objects, etc.), while objects typically use strings as keys.
* **Iteration:** Maps offer methods like `.keys()`, `.values()`, and `.entries()` for efficient iteration over their elements, which can be advantageous in certain scenarios.

**Alternatives:**

While this benchmark focuses on basic lookup performance, other data structures might be more suitable depending on the use case:

* **Arrays:** Efficient for ordered sequences of values and accessing elements by index.
* **Sets:** Store unique values and offer efficient membership testing.

Let me know if you have any further questions!

Related benchmarks:

Map vs Object 10k iterations (version: 0)

Lookup of map vs object

Comparing performance of: Map lookup vs Obj lookup

Created: 4 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 gemma2:9b, generated one year ago):