After deleting one folder at a time in ~/.config/sublime-text-3/ I found that my Session.sublime_metrics file was causing the issue of sublime using 100% CPU.
I confirmed it by
- deleting the whole sublime-text-3 folder
- letting sublime initiate a completely new config
- seeing that sublime uses next to no CPU
- quitting sublime
- copying over the old Session.sublime_metrics file
- launching sublime
- seeing that sublime uses 100% CPU again
See the file here https://gist.github.com/despairblue/38024b807b1817283b15