Benchmark: DataAttribute vs Class Selector vs ID Selector vs AttributeSelector

HTML Preparation code:

<div class="hello" id="hello" data-hello="foo bar baz">Hello</div>

Tests:

Class
document.querySelector('.hello');
ID
document.querySelector('#hello');
data attribute
document.querySelector('[data-hello]');
attribute selector ~ one
document.querySelector('[data-hello~="foo"]');
attribute selector ~ second
document.querySelector('[data-hello~="bar"]');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Class
ID
data attribute
attribute selector ~ one
attribute selector ~ second

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON and explain what's being tested, the options compared, their pros and cons, and other considerations.

**Benchmark Definition**

The benchmark definition is a set of rules that describes how to create a test case for measuring JavaScript performance. It consists of two parts:

1. **Script Preparation Code**: This is an empty string, which means that no code needs to be executed before running the test.
2. **Html Preparation Code**: This defines the HTML structure used for testing. In this case, it creates a simple `<div>` element with an `id`, `data-hello` attribute, and some text content.

**Individual Test Cases**

There are four individual test cases defined in the JSON:

1. **Class Selector**
	* Benchmark Definition: `document.querySelector('.hello');`
	* Test Name: Class
	* Description: This test case uses the `.classSelector` method to select an element based on its class attribute.
2. **ID Selector**
	* Benchmark Definition: `document.querySelector('#hello');`
	* Test Name: ID
	* Description: This test case uses the `#idSelector` method to select an element based on its `id` attribute.
3. **Data Attribute**
	* Benchmark Definition: `document.querySelector('[data-hello]');`
	* Test Name: data attribute
	* Description: This test case uses the `[attribute Selector]` method to select an element based on a custom attribute named `hello`.
4. **Attribute Selector (~ one) and (~ second)**
	* Benchmark Definitions:
		+ `document.querySelector('[data-hello~="foo"]');`
		+ `document.querySelector('[data-hello~="bar"]');`
	* Test Names: attribute selector ~ one, attribute selector ~ second
	* Description: These test cases use the `[attributeSelector]` method with a regular expression to select an element based on a custom attribute named `hello`, where the value must contain "foo" or "bar", respectively.

**Pros and Cons**

Each approach has its own trade-offs:

1. **Class Selector**: Fastest way to select elements by class, but may not work well for elements with multiple classes.
	* Pros: Fast and efficient.
	* Cons: May not work well with elements having multiple classes.
2. **ID Selector**: Slow due to the `querySelectorById` method's implementation, which involves a database-like search.
	* Pros: Works well for elements with unique IDs.
	* Cons: Slower than class selectors.
3. **Data Attribute**: Fast and efficient, but may not work well if the attribute is not present or not in the expected format.
	* Pros: Fast and efficient.
	* Cons: May fail if the attribute is not present or not in the expected format.
4. **Attribute Selector (~ one) and (~ second)**: Uses regular expressions to match attribute values, which can be slow.
	* Pros: Works well for complex attribute patterns.
	* Cons: Slower than other selectors.

**Other Considerations**

1. **Library Usage**: No libraries are explicitly mentioned in the benchmark definition or test cases.
2. **Special JS Features/Syntax**: None are used in this specific benchmark, but some may be present in other benchmarks.
3. **Other Alternatives**: Other ways to select elements include:
	* `document.getElementById('elementId');`
	* `document.getElementsByTagName('tagName');`
	* `Element.prototype.querySelector('[attributeSelector]')`

Note that these alternatives might have different performance characteristics and use cases.

**Conclusion**

The benchmark compares the performance of different JavaScript selectors for selecting HTML elements. Each approach has its pros and cons, and understanding these trade-offs can help developers optimize their code for better performance in real-world applications.

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.0 Safari/537.36

Browser/OS: Chrome 108 on Windows 8.1

View result in a separate tab

Test name	Executions per second
Class	3299271.8 Ops/sec
ID	2512194.2 Ops/sec
data attribute	2272310.2 Ops/sec
attribute selector ~ one	2105571.2 Ops/sec
attribute selector ~ second	2076892.1 Ops/sec

Related benchmarks:

DataAttribute vs Class Selector vs ID Selector vs AttributeSelector (version: 0)

Comparing performance of: Class vs ID vs data attribute vs attribute selector ~ one vs attribute selector ~ second

Created: one year ago by: Guest

Jump to the latest result

Class

ID

data attribute

attribute selector ~ one

attribute selector ~ second

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):