I have been on a mission to look for a solution of how to change the location of every file Google DFS (Drive File Stream) uses (including the DB which gets accessed more than anything). I have two hard drives on my system. One is my OS drive (C:) and one was dedicated (S:) to my cloud related application (such as DFS). When DFS runs it completely consumes my boot/application/OS drive making it a pain to do anything. As you can see, it's not even touching the drive I want it to use for the most part.
I contacted Google support (as I'm an Admin and have the rights to in my company). The response I received from them was as expected but not welcomed...
"Indeed, moving the Drive File Stream content cache doesn't move the operational "db" and other files that are used for the application to run properly. Currently, Drive File Stream can only be installed on the "C" drive on your computer."