GNOME's tracker is a CPU and privacy hog. There's a pretty good case as to why it's neither useful nor necessary here: http://lduros.net/posts/tracker-sucks-thanks-tracker/
After discovering it chowing 2 cores, I decided to go about disabling it.
Directories
Docker filesystem layers can be tricky to wrap your head around, and even more so how indoes work. Lets take an example and see what happens when you tail a file that exists in the image as part of your container entrypoint:
host$ docker run -d --rm --name test-inode debian tail -f /etc/issue
54bbfa8fa1f6751593dcf23103a1cdaec7fde8ffbcb3e31bab466b4f7a3581e7
Now make some changes to the file: