Benchmark: benchmarkname-112312349

HTML Preparation code:

<!DOCTYPE html>
<html>
<head>
</head>
<body>
  <div id="elma"></div>
</body>
</html>

Tests:

byId
var elma = document.getElementById("elma");
qs
var elma = document.querySelector("#elma");
body.qs
var elma = document.body.querySelector("#elma");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
byId
qs
body.qs

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'll explain the JavaScript microbenchmarking process on MeasureThat.net.

**Overview**

MeasureThat.net allows users to create and run JavaScript microbenchmarks, which test the performance of specific JavaScript code snippets or functions. The website provides a simple way for developers to compare the execution times of different approaches to achieve the same goal.

**Benchmark Definition JSON**

The provided benchmark definition JSON contains two essential elements:

1. **Script Preparation Code**: This is an optional section that specifies any initial setup code required to run the test case. In this case, it's empty.
2. **Html Preparation Code**: This is a fixed HTML template used as the base for all tests. The template includes a single `<div>` element with an ID of "elma".

**Individual Test Cases**

The individual test cases are defined in the `Benchmark Definition` section of each test case:

1. **byId**
	* Benchmark definition: `var elma = document.getElementById("elma");`
	* Purpose: Tests the execution time of using `document.getElementById` to select an element with a specific ID.
2. **qs**
	* Benchmark definition: `var elma = document.querySelector("#elma");`
	* Purpose: Tests the execution time of using `document.querySelector` to select an element by its ID or a CSS selector.
3. **body.qs**
	* Benchmark definition: `var elma = document.body.querySelector("#elma");`
	* Purpose: Tests the execution time of using `document.body.querySelector` to select an element with a specific ID within the `<body>` element.

**Library Usage**

None of the test cases use any external libraries.

**Special JS Features or Syntax**

The `querySelector` method is used in all three test cases, which is a modern JavaScript method introduced in ECMAScript 2015 (ES6). This feature allows for more efficient and flexible DOM selection. The `querySelector` method is also supported by older browsers through polyfills or alternative methods like `getElementsByTagName`.

**Other Alternatives**

In theory, developers could use other approaches to achieve the same goal:

* Using `document.getElementsById` instead of `getElementById`
* Using a CSS selector library like jQuery
* Using a different DOM traversal method (e.g., `getElementsByClassName`, `getElementById` with a CSS selector)

However, using `querySelector` is generally considered the most efficient and modern approach for selecting elements in JavaScript.

**Pros and Cons**

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

1. **byId**: Efficient and straightforward, but may not work well for elements with multiple IDs.
2. **qs**: Flexible and efficient, supports CSS selectors, but can be slower due to additional parsing steps.
3. **body.qs**: Similar to `qs`, but uses the `document.body` object as the context, which may have performance implications.

Ultimately, the choice of approach depends on the specific use case and requirements. MeasureThat.net provides a convenient way to compare execution times of different approaches, helping developers make informed decisions about their code optimizations.

Latest run results:

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

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Mobile Safari/537.36

Browser/OS: Chrome Mobile 119 on Android

View result in a separate tab

Test name	Executions per second
byId	1683734.4 Ops/sec
qs	885422.3 Ops/sec
body.qs	1180775.9 Ops/sec

Related benchmarks:

benchmarkname-112312349 (version: 0)

Comparing performance of: byId vs qs vs body.qs

Created: one year ago by: Guest

Jump to the latest result

byId

qs

body.qs

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):