Benchmark: Hashmap vs Array.Filter less

Script Preparation code:

const counter = 100
const map = new Map()
const array = new Array(counter)

window.counter = counter
window.map = map
window.array = array
for (let i = 0; i < counter; i++) {
    map.set(i)
    array[counter] = i
}

Tests:

Hashmap
for (let i = 0; i < 20000; i++) { window.map.has(500) }
Array.filter
for (let i = 0; i < 20000; i++) { window.array.filter((value) => value === 500) }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Hashmap
Array.filter

Fastest: N/A

Slowest: N/A

Latest run results:

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

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

**Benchmark Definition**

The benchmark definition represents two test cases:

1. **Hashmap**: A simple test that checks if `window.map.has(500)` returns true 20,000 times in a row.
2. **Array.filter**: A similar test but with an array (`window.array`) instead of a hashmap. The test checks if `window.array.filter((value) => value === 500)` returns the same value (in this case, `undefined`, because there's no number 500 in the array) 20,000 times in a row.

**Options Compared**

The two options being compared are:

* **Hashmap**: Using a built-in JavaScript object called a `Map` to store key-value pairs.
* **Array.filter**: Using an array and the `filter()` method to create a new array with only the elements that pass a test (in this case, checking if each element is equal to 500).

**Pros and Cons**

Here's a brief summary of the pros and cons of each approach:

* **Hashmap**:
	+ Pros: Fast lookups and updates due to its hash-based data structure.
	+ Cons: Requires more memory to store the map, and the `has()` method may not be as efficient as other methods in some cases.
* **Array.filter**:
	+ Pros: Easy to implement and doesn't require any extra libraries or imports. The resulting array will always have the same length as the original array (because we're filtering out elements).
	+ Cons: Can be slower for large arrays because it creates a new array with fewer elements, which involves more memory allocations and copies.

**Other Considerations**

When choosing between `Map` and `Array.filter`, consider the following:

* If you need fast lookups or updates, `Map` might be a better choice.
* If you're working with large arrays and need to filter out specific values, `Array.filter` might be sufficient. However, keep in mind that it creates a new array, which can impact performance.

**Library Used**

The `Map` object is a built-in JavaScript library (part of the ECMAScript standard) that provides a hash-based data structure for storing key-value pairs. It's supported by most modern browsers and Node.js environments.

**Special JS Feature or Syntax**

There are no special JavaScript features or syntax used in these benchmark definitions. The tests only rely on standard JavaScript methods and properties (e.g., `Map`, `Array.prototype.filter()`, `window.counter`).

**Alternatives**

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

* **Other data structures**: Depending on your specific use case, you might want to experiment with other data structures like Sets, Linked Lists, or even custom-built arrays.
* **Native Array methods**: In addition to `Array.prototype.filter()`, you could also explore other native array methods, such as `Array.prototype.reduce()` or `Array.prototype.forEach()`.
* **Third-party libraries**: For more complex use cases, you might want to consider using third-party libraries like Lodash or Ramda, which provide additional utility functions for working with arrays and data structures.

Keep in mind that these alternatives will likely have different performance characteristics and may not be suitable for all use cases.

Related benchmarks:

Hashmap vs Array.Filter less (version: 0)

Comparing performance of: Hashmap vs Array.filter

Created: 3 years ago by: Guest

Jump to the latest result

Hashmap

Array.filter

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):