What is the problem that needs to be solved? Store (historically) serverStatus.uptime counter info on MongoDB Server process, so that it will be possible to track serverStatus.uptime changes through the time.

Why is it a problem? (the pain) As of now (2020-02-25) there's no way to see historical info of MongoDB Server process restarts since serverStatus.uptime counter is restarted every time MongoDB Server process is restarted. There's no other way (other than going into MongoDB Server process logs) to know if the process was restarted and when it was restarted. If you'd like to calculate MongoDB Server process availability, you'll need to analyze MongoDB Server process logs/monitor MongoDB Server process Process IP (PID).