Benchmark: Array.reduce - MeasureThat.net

Script Preparation code:

const data = [];

for (let i = 0; i < 1000; i ++) {
  data.push([String(i), i]);
}

Tests:

reduce
const data = []; for (let i = 0; i < 1000; i ++) { data.push([String(i), i]); } data.reduce((p, c) => Object.assign(p, c), {});
foreach
const data = []; for (let i = 0; i < 1000; i ++) { data.push([String(i), i]); } const p = {}; data.forEach(c => { p[c[0]] = c[1]; });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
reduce
foreach

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 28 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested, compared, and other considerations.

**Benchmark Definition**

The benchmark is defined by two scripts: `Script Preparation Code` and `Html Preparation Code`. The `Script Preparation Code` initializes an empty array `data` with 1000 elements, where each element is a tuple containing a string representation of a number and the corresponding number itself. This script prepares the data for the subsequent tests.

The `Html Preparation Code` is empty, indicating that no HTML-related preparation is required for this benchmark.

**Individual Test Cases**

There are two test cases:

1. **"reduce"`**: This test case executes the `data.reduce()` method on the prepared `data` array. The reduction function takes an initial value (an empty object `{}`) and iterates through the array, merging each element's properties into the accumulator using `Object.assign()`.
2. **"foreach"`**: This test case uses a traditional `forEach()` loop to iterate through the `data` array, creating a new object with the merged properties.

**Comparison of Approaches**

The two approaches differ in how they handle data manipulation and memory management:

1. **`reduce()`**: The `reduce()` method is a higher-order function that takes an initial value and iterates through the array, accumulating results. This approach has several advantages:
	* Memory efficiency: As each element is processed, only the accumulator's properties are updated, avoiding unnecessary memory allocations.
	* Conciseness: The code is concise and easy to read.
	* Flexibility: The reduction function can be customized to suit specific requirements.
However, `reduce()` may have performance overhead due to:
	* Function call overhead
	* Potential issues with memoization (storing intermediate results)
2. **`forEach()`**: The traditional `forEach()` loop iterates through the array and performs operations on each element. This approach has some advantages:
	* Simplicity: The code is straightforward and easy to understand.
	* Control flow: Each iteration provides an opportunity to add custom logic or side effects.

However, the `forEach()` approach also has potential drawbacks:

* Memory usage: Creating a new object with merged properties can lead to memory fragmentation and increased memory allocation.
	* Code bloat: The loop may become lengthy and harder to read if not properly optimized

**Library: Lodash**

In the "reduce" test case, `Object.assign()` is used, which is part of the Lodash library. Lodash is a popular JavaScript utility library that provides a set of functional programming helpers, including functions for object manipulation, array operations, and more.

The use of Lodash in this benchmark allows developers to easily access and utilize these utilities without having to write their own implementation.

**Special JS Features**

None of the test cases explicitly use special JavaScript features or syntax (e.g., async/await, promises). However, it's worth noting that the `forEach()` loop may benefit from modern browser support for `Array.prototype.forEach()`, which can provide better performance and memory efficiency compared to traditional implementations.

**Alternatives**

Other alternatives for testing array reduction operations might include:

1. **`Array.prototype.every()`**: This method tests if all elements in the array pass a provided test function.
2. **`Array.prototype.some()`**: Similar to `every()`, but returns as soon as at least one element passes the test function.
3. **Custom implementation using a queue data structure**: An alternative approach is to use a queue data structure (e.g., Array or a custom implementation) to process elements in the array, which can provide better performance and control over memory allocation.

Keep in mind that these alternatives may not be as concise or readable as the `reduce()` method, but they offer different trade-offs in terms of performance, memory usage, and code complexity.

Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.75 Safari/537.36

Browser/OS: Chrome 73 on Mac OS X 10.14.3

View result in a separate tab

Test name	Executions per second
reduce	768.6 Ops/sec
foreach	3726.4 Ops/sec

Related benchmarks:

Array.reduce (version: 0)

Comparing performance of: reduce vs foreach

Created: 5 years ago by: Guest

Jump to the latest result

reduce

foreach

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 28 days ago):