experiencing super slow tests with testcafe - testing

Question

I'm currently experimenting testcafe for the first time, I use the testdriven.io course as an example, and I'm facing really slow tests.
For instance testcafe e2e/login.test.js which is basically a register and a login takes sometimes 6min to pass, which I found insanely slow compared to the 15s the author has in his course.
import {Selector} from 'testcafe';
const randomstring = require('randomstring');
const username = randomstring.generate();
const email = `${username}#test.com`;
const TEST_URL = process.env.TEST_URL;
fixture('/login').page(`${TEST_URL}/login`);
test(`should display the sign-in form`, async (t) => {
await t
.navigateTo(`${TEST_URL}/login`)
.expect(Selector('H1').withText('Login').exists).ok()
.expect(Selector('form').exists).ok()
});
test(`should allow a user to sign in`, async (t) => {
// register user
await t
.navigateTo(`${TEST_URL}/register`)
.typeText('input[name="username"]', username)
.typeText('input[name="email"]', email)
.typeText('input[name="password"]', 'test')
.click(Selector('input[type="submit"]'))
// log a user out
await t
.click(Selector('a').withText('Log Out'))
// log a user in
await t
.navigateTo(`${TEST_URL}/login`)
.typeText('input[name="email"]', email)
.typeText('input[name="password"]', 'test')
.click(Selector('input[type="submit"]'))
// assert user is redirected to '/'
// assert '/' is displayed properly
const tableRow = Selector('td').withText(username).parent();
await t
.expect(Selector('H1').withText('All Users').exists).ok()
.expect(tableRow.child().withText(username).exists).ok()
.expect(tableRow.child().withText(email).exists).ok()
.expect(Selector('a').withText('User Status').exists).ok()
.expect(Selector('a').withText('Log Out').exists).ok()
.expect(Selector('a').withText('Register').exists).notOk()
.expect(Selector('a').withText('Log In').exists).notOk()
// log a user out
await t
.click(Selector('a').withText('Log Out'))
// assert '/logout' is displayed properly
await t
.expect(Selector('p').withText('You are now logged out').exists).ok()
.expect(Selector('a').withText('User Status').exists).notOk()
.expect(Selector('a').withText('Log Out').exists).notOk()
.expect(Selector('a').withText('Register').exists).ok()
.expect(Selector('a').withText('Log In').exists).ok()
});
I tried with Firefox, same deal, albeit much faster, 44s.
(project-tOIAx_A8) ➜ testdriven-app git:(master) ✗ testcafe 'chromium' e2e/login.test.js
Using locally installed version of TestCafe.
(node:16048) ExperimentalWarning: The fs.promises API is experimental
Running tests in:
- Chrome 67.0.3396 / Linux 0.0.0
/login
✓ should display the sign in form
✓ should allow a user to sign in
2 passed (6m 15s)
I wish I could provide more info, went to the dev tools, inspected the console without noticing any error message except this one sometimes:
hammerhead.js:7 WebSocket connection to 'ws://192.168.1.195:38039/4wxhbvTF7!w!http%3A%2F%2F172.18.0.5/http://172.18.0.5/sockjs-node/444/2kjm15kn/websocket' failed: Error during WebSocket handshake: Unexpected response code: 400
, the waterfall looks like slow, is there a way to give a log report of it to help understand what cases this slowness ?
edit: I put a .debug() at beginning and at the end of the tests and save a Performance profile inside Firefox if that helps
edit2: this is a performance profile in chromium if that helps