Confusion regarding blogs.dir directory

Hi,
I’ve been using wordpress multisite since wordpress v3.6 or 3.7 (don’t remember which one exactly) with MU Domain Mapping plugin. When I upgraded my wordpress site to multisite at that time I think I forgot to create the blogs.dir directory within wp-contents, but the magical thing is I didn’t face a single issue for that till today.
Today I was doing some research on multisite which I find out about the blogs.dir directory, so I’ve created it inside wp-contents, but its completely blank now, has nothing inside it. I also have no idea which files should be inside that blogs.dir. I already have 2 sites in my network. Is there a way to regenerate the files which should be inside the blogs.dir?
You might be thinking that why am I freaking out while everything is working fine. Well the main reason behind this is very soon I’m going to migrate my site to a nginx vps, so I was thinking as I do not have anything inside blogs.dir folder and as I’ve just created it (though I’ve been using multisite for years), this might cause an issue when I will migrate to the new nginx server. So, guys please help me. Please let me know if there is any way to regenerate the files which should be inside the blogs.dir directory. I’m really scared and freaked out about this after I found it. I cant break my site at any cause. Please help.