Debian Tracker How To Disable
You do not want to uninstall Tracker (on a desktop) as there are dependencies you may want to keep/it makes sense to keep. But Disabling Tracker from auto-start on startup will save resources.
Edit ALL tracker desktop files
sudo vi /etc/xdg/autostart/tracker-*
change this below line from =true to =false
Kill and Remove databases
sudo tracker-control -r