Benchmark: add fields to objects in array

Script Preparation code:

var objects = [{
        a: 'Ghkfj',
        b: 'Yvtzq',
        c: 'Rwsde'
    },
    {
        a: 'Bpqwm',
        b: 'Sdfgh',
        c: 'Zxcvb'
    },
    {
        a: 'Olmnp',
        b: 'Iujkl',
        c: 'Qwerty'
    },
    {
        a: 'Cdsaf',
        b: 'Asdfg',
        c: 'Xcvbn'
    },
    {
        a: 'Qwerz',
        b: 'Cvbnm',
        c: 'Xcvbn'
    }
];

Tests:

map
objects = objects.map(el => ({ ...el, d: Math.random() }));
forEach
objects.forEach(el => el.d = Math.random());
for of
for (let el of objects) el.d = Math.random();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
map
forEach
for of

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36

Browser/OS: Chrome 124 on Windows

View result in a separate tab

Test name	Executions per second
map	796249.1 Ops/sec
forEach	1102060.8 Ops/sec
for of	1169637.1 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON benchmark definition and individual test cases.

**Benchmark Definition**

The `Name` field indicates that this benchmark tests the speed of adding fields to objects in an array. The `Description` provides a brief summary of what the benchmark is checking.

**Script Preparation Code**

This section defines a JavaScript array `objects` with six objects, each containing three properties (`a`, `b`, and `c`). Each object has unique values for these properties.

**Html Preparation Code**

There is no HTML preparation code provided, which means that this benchmark only tests the JavaScript performance and does not involve any DOM-related operations.

**Individual Test Cases**

The benchmark consists of three test cases:

1. **map**: This test case uses the `map()` method to add a new property `d` with a random value to each object in the `objects` array.
2. **forEach**: This test case uses the `forEach()` method to iterate over the `objects` array and add a new property `d` with a random value to each object.
3. **for of**: This test case uses a traditional `for` loop to iterate over the `objects` array and add a new property `d` with a random value to each object.

**Benchmark Results**

The latest benchmark results show that:

* The `map()` method is the fastest, with an execution rate of 1169637.125 executions per second.
* The `forEach()` method is slower than `map()`, but still relatively fast, with an execution rate of 1102060.75 seconds.
* The traditional `for` loop is the slowest, with an execution rate of 796249.0625 seconds.

**Pros and Cons**

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

* **map()**: This method is efficient because it creates a new array with modified objects, which allows for parallel processing and caching. However, it may have higher overhead due to the creation of a new array.
* **forEach():** This method iterates over the array synchronously, which can lead to slower performance compared to `map()`. However, it provides more control over the iteration process.
* **for**: Traditional `for` loops are generally slower because they use a linear search for each element in the array. They also do not provide the same level of parallelism as `map()` or `forEach()`.

**Library and Purpose**

In this benchmark, there is no explicit library used. However, the `map()` and `forEach()` methods rely on the built-in JavaScript functions to operate on arrays.

**Special JS Feature or Syntax**

There are no special features or syntax used in this benchmark that would require specific knowledge of JavaScript beyond basic concepts.

Now, regarding alternatives to MeasureThat.net:

* **Benchmarking tools:** Other popular benchmarking tools for JavaScript include:
	+ Benchmark.js
	+ jsPerf
	+ Microbenchmark (a command-line tool)
* **Profiling tools:** Tools like Chrome DevTools or Node.js Inspector can provide more detailed information about performance issues and optimization opportunities.
* **Testing frameworks:** Frameworks like Jest, Mocha, or Cypress can be used to write test cases for JavaScript applications, but they are not specifically designed for benchmarking.

Keep in mind that MeasureThat.net is a specialized tool for benchmarking JavaScript performance, so it's essential to use it when you need to compare the speed of different JavaScript implementations or variations.

Related benchmarks:

add fields to objects in array (version: 0)

speed of different variants of adding field into objects in array

Comparing performance of: map vs forEach vs for of

Created: one year ago by: Guest

Jump to the latest result

map

forEach

for of

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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