How to render quicker a Symfony3 app on an VirtualBox Ubuntu VM hosted by Windows 10?

So I have this web-app which is roughly like a complex Back-Office accessible through a sconnection with a login/password.

It's a Symfony3.0 application running with PHP5.6, MySQL and Apache 2.4.

In order to set up properly my dev environment, I've choosen to use a VirtualBox Virtual Machine to do the job as the web server. I access it from the host machine thanks to the Bridge Connection that makes the VM appear as another computer of my local aera network (192.168.1.33).

My problem is that I render the website (accessing app_dev.php) in ~7900ms (to say the least). This rendering is gotten from the Symfony web-toolbar at the bottom of the screen, that is to say the DOM rendering is not taken into account.

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The VM has 8192Mo of RAM, shares a 12Go virtual disk-drive and has been provided with 4 cores of my processor.

So far, I tried:

  • increasing the VM specifications to gain performances, to no avail;
  • installed WAMP to gain several seconds to reach ~2500ms (but I don't want to work with WAMP);
  • installed Docker for Windows but Kaspersky, despite configurating it properly, won't let my drive been shared to Docker.

What could I do to render my website in, say, 3000 / 3500ms? Am I missing something obvious? Is what I'm asking even possible?

Feel free to ask any needed info!