Benchmark: get element - MeasureThat.net

HTML Preparation code:

<div id='test'></div>
<div class='test2'></div>

Tests:

test
document.getElementById('test');
test2
document.getElementsByClassName('test2')[0];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
test
test2

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Measuring JavaScript performance is crucial in ensuring that our code runs efficiently and effectively across various browsers and devices.

Let's break down the provided JSON data to understand what's being tested:

**Benchmark Definition**

The benchmark definition represents a single test case, which consists of a JavaScript expression that's executed repeatedly. In this case, we have two test cases: `test` and `test2`. The script preparation code is empty, indicating that no setup or initialization is required for these tests.

The HTML preparation code includes two HTML elements: `<div id='test'></div>` and `<div class='test2'></div>`. These elements are used as targets for the JavaScript expressions in the test cases.

**Test Cases**

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

1. `test`: This test case executes the expression `document.getElementById('test');`, which retrieves an element by its ID.
2. `test2`: This test case executes the expression `document.getElementsByClassName('test2')[0];`, which retrieves a class name and returns the first element with that class.

**Comparison of Options**

In JavaScript, there are two main ways to access elements in the DOM:

1. **`getElementById()`**: This method takes an ID as a string argument and returns the element with that ID.
2. **`getElementsByClassName()`**: This method takes a class name as a string argument and returns a collection of elements with that class.

The pros and cons of these approaches are:

* `getElementById()`:
	+ Pros: Faster, more efficient, and more accurate for single-element lookups.
	+ Cons: Only works if the element exists, and it can be slower for complex queries.
* `getElementsByClassName()`:
	+ Pros: More flexible and reusable, especially for class-based layouts.
	+ Cons: Can be slower due to the DOM traversal, and returns a collection of elements.

**Library and Purpose**

The provided JSON data doesn't explicitly mention any libraries. However, it's likely that the JavaScript expressions in the test cases are using the browser's built-in `document` object.

No special JS features or syntax are used in these test cases.

**Other Alternatives**

If you want to measure performance for different scenarios, consider adding additional test cases with varying:

* Element types (e.g., `getElementsByTagName()`, `querySelector()`)
* Class names or IDs
* CSS selectors
* DOM structure complexity

When using libraries like jQuery, Lodash, or other utility functions, they might be used in your benchmarking scripts. For example, you could use `$(selector).get()` instead of `document.querySelector(selector)`.

Keep in mind that library usage can impact performance, so consider adding test cases with and without these libraries to get a more accurate picture of the benefits and drawbacks.

**Measurement Techniques**

To measure JavaScript performance accurately, consider using techniques like:

* Benchmarking frameworks (e.g., Benchmark.js)
* Profiling tools (e.g., Chrome DevTools, Firefox Developer Edition)
* Micro-benchmarking libraries (e.g., micro-benchmark)

These tools can help you analyze and optimize your code for better performance.

By considering these factors, you'll be able to gain a deeper understanding of how different JavaScript approaches impact performance, allowing you to make informed decisions when writing efficient and effective code.

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:88.0) Gecko/20100101 Firefox/88.0

Browser/OS: Firefox 88 on Windows

View result in a separate tab

Test name	Executions per second
test	3512520.5 Ops/sec
test2	1602070.2 Ops/sec

Related benchmarks:

get element (version: 0)

Comparing performance of: test vs test2

Created: 3 years ago by: Guest

Jump to the latest result

test

test2

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):