Benchmark: fill vs map - MeasureThat.net

Script Preparation code:

var arr = [];

for (let i = 0; i < 100000; i++) arr.push(i);

Tests:

Map
const array = arr.map(() => 0);
Fill
const array = new Array(arr.length).fill(0);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Map
Fill

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one month ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36

Browser/OS: Chrome 130 on Linux

View result in a separate tab

Test name	Executions per second
Map	620.5 Ops/sec
Fill	3300.4 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what is tested, the options compared, pros and cons of each approach, library usage, special JavaScript features, and other considerations.

**Benchmark Definition**

The benchmark definition represents a JavaScript code snippet that creates an array using two different methods: `map()` and `fill()`. The script preparation code generates an empty array `arr` with 100,000 elements, which is then used to create the arrays in the test cases.

**Test Cases**

There are two test cases:

1. "Map": This test case creates an array using the `map()` method, where each element is set to 0.
2. "Fill": This test case creates an array using the `fill()` method, where all elements are set to 0.

**Options Compared**

The benchmark compares two approaches for creating arrays:

1. **Map**: The `map()` method applies a function to every element in the original array and returns a new array with the results.
2. **Fill**: The `fill()` method creates a new array filled with a specified value (in this case, 0).

**Pros and Cons of Each Approach**

1. **Map**:
	* Pros: More flexible, as it allows you to apply different functions to each element.
	* Cons: Can be slower due to the overhead of applying a function to each element, especially for large arrays.
2. **Fill**:
	* Pros: Generally faster, as it simply copies the value to each element without applying any function.
	* Cons: Less flexible, as you're limited to setting all elements to the same value.

**Library Usage**

There is no explicit library usage in this benchmark, but `Array.prototype.map()` and `Array.prototype.fill()` are part of the JavaScript language itself. However, it's worth noting that some older browsers or environments might not support these methods.

**Special JavaScript Features**

None mentioned in the provided code snippet.

**Other Considerations**

* The benchmark uses a fixed array size (100,000 elements), which may not accurately represent real-world scenarios where array sizes can vary.
* There is no consideration for other types of arrays, such as sparse arrays or arrays with duplicate values.
* There is also no comparison between using `map()` and `fill()` on different types of data structures, like objects or sets.

**Alternatives**

If you were to design a similar benchmark, you might consider the following alternatives:

1. Compare using `reduce()` instead of `map()`.
2. Use a different method for creating arrays, such as using the `Array.from()` constructor.
3. Compare performance on different types of data structures, like objects or sets.
4. Measure performance with varying array sizes to see how it affects the outcome.

Keep in mind that these alternatives would require modifications to the benchmark definition and test cases.

Related benchmarks:

fill vs map (version: 0)

Comparing performance of: Map vs Fill

Created: 3 years ago by: Guest

Jump to the latest result

Map

Fill

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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