Benchmark: twoja stara - MeasureThat.net

Script Preparation code:

var arr = [];

var createItem = function(group, value) {
  return {
    group: group,
    value: value
  }
}
const I = 12345
for (var i = 0; i < I; i++) {
  arr[i] = createItem(i < I/2 ? 'section': 'nosection', i);
}

Tests:

reduce
arr.reduce((acc, filter) => { if (filter.group === 'sections') acc.push(filter.value); return acc; }, []);
filter + map
arr.filter(_ => _.group === 'sections') .map(_ => _.value);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
reduce
filter + map

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

I'd be happy to help you understand the JavaScript microbenchmarking test case on MeasureThat.net.

**Benchmark Definition JSON**

The provided benchmark definition is a JSON object that contains information about the test case. Here's what it represents:

* `Name`: The name of the benchmark, which is "twoja stara" in this case.
* `Description`: An empty string, indicating that there is no description for this benchmark.
* `Script Preparation Code`: A JavaScript function named `createItem` that creates an object with two properties: `group` and `value`. The script also initializes an array `arr` and populates it with `I` number of elements using the `createItem` function. The value of `I` is set to 12345.
* `Html Preparation Code`: An empty string, indicating that there is no HTML preparation code for this benchmark.

The purpose of this script is to create an array of objects and then filter and map over it.

**Individual Test Cases**

There are two individual test cases defined in the JSON object:

1. **"reduce"`**
	* `Benchmark Definition`: A JavaScript function that calls the `reduce` method on the `arr` array, passing a callback function as an argument.
	* This test case measures the performance of the `reduce` method when used to accumulate values from an array.

2. **"filter + map"`**
	* `Benchmark Definition`: A sequence of two methods: `filter` and `map`, applied to the `arr` array in that order.
	* This test case measures the performance of filtering and mapping over an array using these two methods.

**Library Usage**

The benchmark uses the built-in JavaScript Array object, which provides various methods for manipulating arrays. Specifically:

* The `reduce` method is used in one of the test cases to accumulate values from the array.
* The `filter` and `map` methods are used sequentially in another test case to filter and transform an array.

**Special JS Feature or Syntax**

The benchmark uses a common JavaScript syntax feature: **block scope variables**. In particular, the `var` keyword is used to declare the `createItem` function and its local variable `i`. This allows the code to use block scope to avoid polluting the global namespace and reducing potential naming conflicts.

However, it's worth noting that modern JavaScript engines like Chrome have a concept of **lexically scoped variables**, which can provide better performance and security compared to traditional block-scoped variables. But for this benchmark, the use of `var` is deliberate to mimic older JavaScript implementations or to test specific scenarios.

**Alternatives**

There are several alternatives to MeasureThat.net for running JavaScript microbenchmarks:

1. **J Benchmark**: A popular open-source tool for measuring the performance of JavaScript code.
2. **jsperf**: Another widely used benchmarking tool for JavaScript, which provides a simple and easy-to-use interface for defining benchmarks.
3. **Benchmark.js**: A lightweight library for creating and running benchmarks in JavaScript, which can be used as a standalone tool or integrated into existing projects.

These alternatives may offer different features, performance characteristics, or ease of use compared to MeasureThat.net. However, all of them provide a good starting point for testing and optimizing JavaScript code performance.

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.130 Safari/537.36

Browser/OS: Chrome 79 on Linux

View result in a separate tab

Test name	Executions per second
reduce	5624.9 Ops/sec
filter + map	4390.4 Ops/sec

Related benchmarks:

twoja stara (version: 0)

Comparing performance of: reduce vs filter + map

Created: 4 years ago by: Guest

Jump to the latest result

reduce

filter + map

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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