Benchmark: querySelector vs querySelector + cache

HTML Preparation code:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<h1 class="about-shop">Hello azula</h1>
</body>
</html>

Script Preparation code:

const cache = {};

    function $(selector) {
        if (cache[selector] !== undefined) {
            console.count("cached");
            return cache[selector];
        }

        const cached = document.querySelector(selector);
        cache[selector] = cached;
        return cached
    };

Tests:

querySelector
const selector1 = document.querySelector(".about-shop"); const selector2 = document.querySelector(".about-shop"); const selector3 = document.querySelector(".about-shop");
querySelector + cache
const selector1 = $(".about-shop"); const selector2 = $(".about-shop"); const selector3 = $(".about-shop");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
querySelector
querySelector + cache

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 8 days ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36

Browser/OS: Chrome 123 on Windows

View result in a separate tab

Test name	Executions per second
querySelector	1682733.0 Ops/sec
querySelector + cache	68357.1 Ops/sec

querySelector vs querySelector + cache (version: 0)

Comparing performance of: querySelector vs querySelector + cache

Created: 3 years ago by: Registered User

Jump to the latest result

querySelector

querySelector + cache

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A