codeception in yii2 requires ubelieveble amount of memory

I cannot run my functional tests because my machine does not have enough memory.

Is there a way to reduce memory usage of Codeception?

Below is my functional test that requires over 7GB of RAM:

<?php


namespace functional\controllers;


use FunctionalTester;

class TicketControllerCest
{

    public function _before(FunctionalTester $I)
    {
        $I->amOnPage('ticket/list');
    }

    public function openTicketListPage(FunctionalTester $I)
    {
        $I->see("test", "h1");
    }
}

In _bootstrap.php i turned off deep clone like so:

\Codeception\Specify\Config::setDeepClone(false);