Dynamic URL cause high memory usage

[dpreindl]

Brief summary

When running a k6 browser based test with multiple VUs, I noticed a steady increase of used memory. After trying to reduce the tests to a bare minimum, I came to the conclusion that this is caused by dynamic/non-unique URLs which are being called by the browser during the tests.
For me it seems that this is the browser version of what is being described in the k6 docs as url grouping here and here. - I would suspect the issue being related to the metric browser_http_req_duration.

xk6-browser version

1.2.1

OS

Debian Linux

Chrome version

Chromium 120.0.6099.199

Docker version and image (if applicable)

No response

Steps to reproduce the problem

Demo HTML page (Page with a title and a link):
demo-page.zip
Two versions are included:

• index.html -> Clicking the link calls a dynamic URL (just adding the timestamp as query)
• demo.html -> Clicking the link calls the same URL every time

Test script:

import { sleep } from "k6";
import { browser } from "k6/experimental/browser";

const DURATION = __ENV.DURATION || 2; // in minutes
const TARGET_VUS = __ENV.VUS || 1;
const URL = __ENV.URL || "http://127.0.0.1:8080/";

export const options = {
  scenarios: {
    DemoTest: {
      exec: "testDemoPage",
      executor: "ramping-vus",
      stages: [
        { duration: `${2 * 60}s`, target: TARGET_VUS }, // 2 minutes
        { duration: `${DURATION * 60}s`, target: TARGET_VUS },
      ],
      options: {
        browser: {
          type: "chromium",
        },
      },
    },
  },
};

export async function testDemoPage() {
  const page = browser.newPage();
  try {
    await page.goto(URL);
    for (let i = 0; i < 50; i++) {
      await page.locator("#load").click();
      sleep(0.2);
    }
  } finally {
    page.close();
  }
}

Expected behaviour

Moderate increase of memory

Actual behaviour

Running the Test with dynamic URLs being called results in a steady increase of memory (~ additionally 1 GB / hour):

The same test without the dynamic URL part:

Details (dynamic URLs):

• pprof results (heap, allocation, go routines) & ps aux result after: 5min (base), ~40mn, ~60min
  dynamic-urls.zip

Details (same URL):

• pprof results (heap, allocation, go routines) & ps aux result after: 5min (base), ~110min
  same-url.zip

[inancgumus]

I'm adding this issue to the main #1138 issue. Thanks for reporting.