Benchmark: style vs. style.cssText

HTML Preparation code:

<div id='a'>foo</div>
<div id='b'>bar</div>

Script Preparation code:

var a = document.getElementById('a');
var b = document.getElementById('b');

Tests:

style
a.style.fontSize = `${20 * Math.random()}px`; a.style.letterSpacing = `-${Math.random()}em`; a.style.wordSpacing = '0em'; const x = a.getBoundingClientRect();
style.cssText
b.style.cssText = ` font-size: ${20 * Math.random()}px; letter-spacing: -${Math.random()}em; word-spacing: 0em; `; const x = b.getBoundingClientRect();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
style
style.cssText

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Windows

View result in a separate tab

Test name	Executions per second
style	10809.0 Ops/sec
style.cssText	13095.9 Ops/sec

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

LLMs can make mistakes. Check important info.

The provided JSON represents two benchmark test cases for measuring the performance of JavaScript's CSS styling features.

**Benchmark Definition**

The first benchmark definition is:

"var a = document.getElementById('a');\r\nvar b = document.getElementById('b');"

This code retrieves two HTML elements, `a` and `b`, from the DOM. The purpose of this test case is to measure the performance of accessing and manipulating CSS styles on these elements.

The second benchmark definition is:

"b.style.cssText = `\r\n  font-size: ${20 * Math.random()}px;\r\n  letter-spacing: -${Math.random()}em;\r\n  word-spacing: 0em;\r\n`;\r\nconst x = b.getBoundingClientRect();"

This code sets the `cssText` property of element `b` to a string containing random font size, letter spacing, and word spacing styles. The purpose of this test case is to measure the performance of applying these styles.

**Options Compared**

The two benchmark test cases compare the performance of:

1. Setting inline styles on an element (`a.style.fontSize = ...;`) versus setting CSS styles via `cssText` property (`b.style.cssText = ...;`).
2. Using a JavaScript object (`var x = ...`) to access and manipulate style properties compared to using the `getBoundingClientRect()` method.

**Pros and Cons**

1. **Setting inline styles**:
	* Pros: More precise control over styles, can be faster for simple styles.
	* Cons: Can lead to more complex CSS rules, may require more computational resources.
2. **Setting CSS styles via `cssText` property**:
	* Pros: Easier to manage and maintain large numbers of styles, faster for larger sets of styles.
	* Cons: May be slower for simple styles or when applying individual styles.
3. **Using a JavaScript object vs. `getBoundingClientRect()`**:
	* Pros: Faster access to style properties for simple queries.
	* Cons: Requires more computational resources and may lead to slower performance for complex queries.

**Library**

There is no explicit library mentioned in the provided JSON. However, the use of `document.getElementById()` and `getBoundingClientRect()` suggests that the test case is relying on standard JavaScript APIs.

**Special JS Feature/Syntax**

The provided benchmark does not explicitly use any special JavaScript features or syntax. It appears to be a basic comparison of two styling approaches.

**Other Considerations**

When writing benchmarks, it's essential to consider factors such as:

* Test scope: Is the test case representative of real-world usage?
* Data distribution: Are the random values used in the benchmark cases well-distributed and representative of possible input scenarios?
* System load: Does the benchmark account for system load, network latency, or other external factors that may affect performance?

**Alternatives**

Alternative approaches to this benchmark could include:

* Testing with different types of elements (e.g., images, tables) or attributes.
* Measuring the impact of various CSS styles on performance (e.g., animations, gradients).
* Using more realistic input data (e.g., a large dataset of random values).
* Accounting for system load or network latency in the benchmarking process.

Keep in mind that these alternative approaches would require careful consideration of the test's scope and requirements to ensure accurate results.

Related benchmarks:

style vs. style.cssText (version: 0)

Comparing performance of: style vs style.cssText

Created: 6 years ago by: Registered User

Jump to the latest result

style

style.cssText

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):