the database is fault tolerant, it means in most cases it will save the state.
after crash it will try to save everything, theoretically it may misfire but it looks like it works.
if you invoke 'save all' and then kill the process or press the reset button it will remember the save point (and all bodies downloaded afterwards).
so it would be trivial to add 'save in x minutes' to guard against system crashes, if ue crashes itself, as a rule it will save everything and then exit.