Benchmark: Get value with key in Array, Object, Map, WeakMap

Tests:

Map.get
const map = new Map(); map.get('0');
weakMap.get
const weakMap = new WeakMap(); weakMap.get('0');
Array
const array = []; array[0];
Object
const object = {}; object.a;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Map.get
weakMap.get
Array
Object

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.93 Safari/537.36

Browser/OS: Chrome 90 on Linux

View result in a separate tab

Test name	Executions per second
Map.get	4181675.5 Ops/sec
weakMap.get	3425960.8 Ops/sec
Array	472364960.0 Ops/sec
Object	520553376.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

LLMs can make mistakes. Check important info.

Let's dive into the provided JSON and explore what's being tested in this JavaScript microbenchmark.

**Benchmark Definition**

The benchmark definition is quite straightforward: it measures the execution time of accessing values with keys in different data structures - arrays, objects, maps (with both weak and regular maps), and weak maps. The goal is to compare the performance of these different approaches.

**Options Compared**

Here are the options being compared:

1. **Arrays**: Accessing an element at a specific index using bracket notation (`array[0]`).
2. **Objects**: Accessing a property value using dot notation (`object.a`).
3. **Maps (regular)**: Accessing a value with a key using the `get()` method (`map.get('0')`).
4. **Weak Maps**: Accessing a value with a key using the `get()` method (`weakMap.get('0')`).

**Pros and Cons of Each Approach**

Here's a brief overview of each approach:

1. **Arrays**:
	* Pros: Arrays are a fundamental data structure in JavaScript, and accessing elements by index is a common operation.
	* Cons: For large arrays, this can be an O(n) operation, which might lead to poor performance for big datasets.
2. **Objects**:
	* Pros: Objects allow for flexible key-value pairs, making them suitable for many use cases.
	* Cons: Accessing properties by dot notation is not as efficient as accessing elements by index in arrays.
3. **Maps (regular)**:
	* Pros: Maps provide fast lookups using the `get()` method, which has an average time complexity of O(1).
	* Cons: Maps can lead to memory leaks if not properly cleaned up, and their performance might degrade for very large datasets.
4. **Weak Maps**:
	* Pros: Weak maps are similar to regular maps but provide automatic garbage collection for keys that are no longer referenced.
	* Cons: The `get()` method still has an average time complexity of O(1), and the benefits of weak maps depend on the specific use case.

**Library Usage**

In this benchmark, none of the libraries (e.g., jQuery) is explicitly mentioned. However, it's worth noting that some data structures might rely on underlying library implementations or optimizations.

**Special JS Features/Syntax**

None of the benchmark definitions explicitly uses special JavaScript features like async/await, Promises, or modern syntax (e.g., arrow functions). This suggests that the focus is on basic, straightforward access operations rather than more complex use cases.

**Alternatives**

If you're interested in exploring alternative approaches, consider the following:

1. **Use a benchmarking library**: Tools like `benchmark` or `micro-benchmark` provide more structured benchmarks and might offer additional features, such as support for multiple execution modes (e.g., async/await).
2. **Write your own benchmark**: Create a simple script that runs each benchmark definition repeatedly, measuring the execution time using a tool like `performance.now()` or `Date`.
3. **Use online benchmarking platforms**: Websites like [jsbench.net](https://jsbench.net/) allow you to create and share benchmarks with others.

Keep in mind that this specific benchmark focuses on basic access operations, so it might not be directly applicable for more complex use cases. However, understanding the underlying principles can help you develop your own benchmarks or optimize existing code.

Related benchmarks:

Get value with key in Array, Object, Map, WeakMap (version: 0)

Comparing performance of: Map.get vs weakMap.get vs Array vs Object

Created: 3 years ago by: Guest

Jump to the latest result

Map.get

weakMap.get

Array

Object

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):