Benchmark: Test_our_data - MeasureThat.net

HTML Preparation code:

<div class="cow">
	<p class="small_cow" id="cow_1"></p>
  	<p class="small_cow"></p>
</div>

Script Preparation code:

document.getElementById("cow_1")

Tests:

Class
document.getElementsByClassName("small_cow")
Tag name
document.getElementsByTagName("p")

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Class
Tag name

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 7 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36

Browser/OS: Chrome 61 on Mac OS X 10.13.1

View result in a separate tab

Test name	Executions per second
Class	3057986.2 Ops/sec
Tag name	3099608.5 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the test cases and explain what's being tested, along with the pros and cons of each approach.

**What is being tested?**

The provided benchmark tests two different ways to retrieve elements in HTML documents using JavaScript:

1. `document.getElementsByClassName("small_cow")` (Class-based retrieval)
2. `document.getElementsByTagName("p")` (Tag name-based retrieval)

These methods are used to find and retrieve specific elements within an HTML document.

**Approach 1: Class-based retrieval (`document.getElementsByClassName("small_cow")`)**

In this approach, the code uses the `getElementsByClassName()` method to retrieve all elements that have a class attribute with the value "small_cow". This method returns a NodeList (a collection of nodes) containing all matching elements.

**Pros:**

* Fast and efficient, as it only searches for matching classes in the DOM tree.
* Can be used to select multiple elements based on their class names.

**Cons:**

* May return a large number of elements if there are many elements with the same class name.
* Does not guarantee uniqueness among matching elements (e.g., if two elements have both "small_cow" and another class, they will still match).

**Approach 2: Tag name-based retrieval (`document.getElementsByTagName("p")`)**

In this approach, the code uses the `getElementsByTagName()` method to retrieve all elements with a tag name of "p". This method returns an HTMLCollection (a collection of nodes) containing all matching elements.

**Pros:**

* Guarantees uniqueness among matching elements, as each element is uniquely identified by its tag name.
* Can be used to select only one element based on its tag name.

**Cons:**

* Slower and less efficient than class-based retrieval, especially for large HTML documents or complex layouts.
* May not return any elements if no elements with the specified tag name exist in the document.

**Library/Library feature:**

None of these methods use a specific JavaScript library. However, `getElementsByClassName()` is a standard method provided by most modern browsers.

**Special JS feature/syntax:**

None mentioned.

Now, let's talk about alternatives:

1. **QuerySelector()**: This method provides a more modern and efficient way to select elements based on their CSS selectors. It can be used in conjunction with the class-based retrieval approach above.
2. **CSS Selectors**: Browsers also support using CSS selectors to retrieve elements. While this method is not as fast as `getElementsByClassName()` or `querySelector()`, it provides more flexibility and power.
3. **DOM manipulation libraries**: Some JavaScript libraries, like jQuery, provide their own set of methods for manipulating the DOM tree. These libraries often provide faster and more efficient ways to select and manipulate elements.

In summary, class-based retrieval (`getElementsByClassName()`) is generally faster and more efficient than tag name-based retrieval (`getElementsByTagName()`), but it may not guarantee uniqueness among matching elements. QuerySelector() or CSS selectors can provide an alternative way to select elements based on their CSS selectors.

Related benchmarks:

Test_our_data (version: 0)

Comparing performance of: Class vs Tag name

Created: 7 years ago by: Guest

Jump to the latest result

Class

Tag name

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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