Deadlock in the cloud

[sniku]

The browser test seems to dead-lock after 3-10min. This is likely not related to the cloud, but it's easiest to spot it there because the metrics stop being generated while k6 continues to run.

• CPU drops to near 0%.
• The memory stays constant. (which probably means that the chromium process is running)
• no iterations are being executed
• no browser metrics are being collected

Sample script:

import { check } from 'k6';
import { chromium } from 'k6/x/browser';

export let options = {
  vus: 1,
  duration: '50m'
}

export default function () {
  const browser = chromium.launch('chromium', {
    headless: true,
  });
  const context = browser.newContext();
  const page = context.newPage();

  // Goto front page, find login link and click it
  page.goto('https://test.k6.io/', { waitUntil: 'networkidle' });
  const elem = page.$('a[href="/my_messages.php"]');
  elem.click().then(() => {
    // Enter login credentials and login
    page.$('input[name="login"]').type('admin');
    page.$('input[name="password"]').type('123');
    return page.$('input[type="submit"]').click();
  }).then(() => {
    // We expect the above form submission to trigger navigation, so wait for it
    // and the page to be loaded.
    page.waitForNavigation();

    check(page, {
      'header': page.$('h2').textContent() == 'Welcome, admin!',
    });
  }).finally(() => {
    page.close();
    browser.close();
  });
}

[ankur22]

We think the deadlock issue in the cloud (#496) is the same as issue as the test timeout issue in waitForExecutionContext (#482).

deadlock-cloud-stacktrace.txt

The fix and further details will be raised in #482, unless we find something else.

[ankur22]

We believe that this has been resolved (for now) with PR #555 (issue #553, which was created due to the deadlock issue). We have ran several tests locally and int he cloud and it hasn't resurfaced yet. There's a chance that this could still occur though (obviously in case we missed anything) if the CDP events are sent out of order by the browser.