Benchmark: Attribute vs Class Selector vs ID Selector

HTML Preparation code:

<div class="hello" id="hello" hello>Hello</div>

Tests:

Class
document.querySelector('.hello');
ID
document.querySelector('#hello');
data attribute with given value
document.querySelector('[hello=""]');
data attribute without given value
document.querySelector('[hello]');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Class
ID
data attribute with given value
data attribute without given value

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Class	7462985.0 Ops/sec
ID	5839545.0 Ops/sec
data attribute with given value	5065728.5 Ops/sec
data attribute without given value	5029450.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark definition and test cases to understand what is being tested.

**Benchmark Definition**

The benchmark definition consists of a JSON object that describes the experiment. In this case, we have four different test cases:

1. `Attribute vs Class Selector vs ID Selector`
2. `Class`
3. `ID`
4. `data attribute with given value`
5. `data attribute without given value`

This suggests that the benchmark is comparing the performance of three different types of selectors: attribute selectors, class selectors, and ID selectors.

**Selector Types**

Here's a brief explanation of each selector type:

* **Attribute selectors**: These selectors use a format like `[attribute="value"]` to select elements based on the presence of a specific attribute. For example, `[hello=""]`.
* **Class selectors**: These selectors use a format like `.class` to select elements based on their class name. For example, `.hello`.
* **ID selectors**: These selectors use a format like `#id` to select elements based on their ID attribute. For example, `#hello`.

**Library and Purpose**

In the benchmark preparation code, we see that the script prepares the HTML document using `document.querySelector()`. This is not a library in itself but rather an API function provided by the browser.

However, some libraries might be used implicitly or explicitly to manipulate DOM elements. In this case, no specific libraries are mentioned.

**Special JS Features and Syntax**

None of the test cases involve special JavaScript features or syntax that would affect performance significantly.

**Benchmark Options Compared**

The benchmark is comparing the performance of three different selector types:

1. **Attribute selectors**: Selecting elements based on attribute values.
2. **Class selectors**: Selecting elements based on class names.
3. **ID selectors**: Selecting elements based on ID attributes.

These options are compared to determine which one performs better in terms of execution speed.

**Pros and Cons**

Here's a brief pros and cons analysis for each selector type:

* **Attribute selectors**:
	+ Pros: Highly flexible and customizable.
	+ Cons: May be slower due to the overhead of parsing attribute values.
* **Class selectors**:
	+ Pros: Generally faster than attribute selectors, as class names are often shorter.
	+ Cons: Less flexible than attribute selectors, as class names must match exactly.
* **ID selectors**:
	+ Pros: Fastest option, as IDs are typically unique and easy to parse.
	+ Cons: May not be suitable for selecting elements with multiple IDs.

**Other Alternatives**

If the browser does not support CSS Selectors or if you want to use a different approach, here are some alternative methods:

1. **DOM traversal**: Iterate through the DOM tree using `node.parentNode` or other equivalent methods.
2. **Regular expressions**: Use regular expressions to match elements based on their attributes or class names.
3. **Native JavaScript APIs**: Use native JavaScript APIs like `querySelectorAll()` or `getElementsByClassName()`.

Keep in mind that these alternatives might be slower and less efficient than using CSS Selectors, especially for large DOM datasets.

I hope this explanation helps you understand the benchmark and its test cases!

Related benchmarks:

Attribute vs Class Selector vs ID Selector (version: 0)

Comparing performance of: Class vs ID vs data attribute with given value vs data attribute without given value

Created: one year ago by: Guest

Jump to the latest result

Class

ID

data attribute with given value

data attribute without given value

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):