Benchmark: document.head vs document.getElementsByTagName

HTML Preparation code:

<html>
<head id="myHead">
<title>My title</title>
</head>
<body><p id="demo"></p>
</body>
</html>

Tests:

2
var css = document.head;
3
var css = document.getElementsByTagName("head")[0];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
2
3

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.0.0 Safari/537.36

Browser/OS: Chrome 109 on Windows

View result in a separate tab

Test name	Executions per second
2	4692277.0 Ops/sec
3	3381999.2 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what's being tested in this benchmark and explore the options compared, pros and cons, and other considerations.

**What is being tested?**

The benchmark is testing two ways to access the `<head>` element of an HTML document: using `document.head` versus `document.getElementsByTagName("head")[0]`.

**Options compared:**

There are two options:

1. **`document.head`**: This method returns a direct reference to the `<head>` element, which can be accessed directly.
2. **`document.getElementsByTagName("head")[0]`**: This method returns an array of all elements with the tag name "head" and returns the first element in the array.

**Pros and Cons:**

1. `document.head`:
	* Pros: Direct access to the `<head>` element, potentially faster since it doesn't require searching for the element.
	* Cons: May not be available in older browsers that don't support HTML5, and may cause issues if the document has multiple `<head>` elements.
2. `document.getElementsByTagName("head")[0]`:
	* Pros: Widely supported across browsers, even older ones. Can handle cases where there are multiple `<head>` elements.
	* Cons: May be slower since it requires searching for the element in an array.

**Other considerations:**

* **Library usage:** None of the options use a library specifically designed for benchmarking or performance comparison.
* **JavaScript features/syntax:** The benchmark uses basic JavaScript syntax and doesn't include any advanced features like async/await, generators, or decorators.

**Benchmark preparation code:**

The HTML preparation code creates an HTML document with a `<head>` element that contains a title. The script preparation code is empty, which means the test scripts will only contain the lines of code being compared.

**Other alternatives:**

If you're interested in benchmarking other JavaScript-related scenarios, here are some alternative approaches:

* **Bench.js**: A popular benchmarking library for Node.js and browsers.
* **Benchmarkist**: A simple and efficient benchmarking tool for JavaScript applications.
* **V8 benchmarking**: Google's V8 engine provides its own benchmarking tools for testing JavaScript performance.

Keep in mind that these alternatives might have different features, complexity levels, or requirements compared to the MeasureThat.net approach.

Related benchmarks:

document.head vs document.getElementsByTagName (version: 0)

Comparing performance of: 2 vs 3

Created: 7 years ago by: Guest

Jump to the latest result

2

3

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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