When you are working in Origin and haven't saved the project yet, it's called Untitled.opju.

1. In the past, autosave would kick in every N minutes for such untitled.opju no matter how big the data is, which can be annoying and time conusming. Origin 2020 will check the current workspace size and give warning if more than 20MB for user to decide if autosave it or not. 
2. Set system variable @DASU=1 to turn off Autosaving of Untitled.opju.