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FrodeSolheim · 18 May 2021, 22:05

There is a reason the option is called unsafe_save_states.

The save states are not safe to use in all circumstances. One particular reason is that the disk (hard or floppy) contents are not stored within the savestate. So, if data is stored back to the disk, the disk storage might get out of sync with the savestate, causing inconsistencies and data corruption. This could also happen for floppy-based games btw.

If the game saves data that it later depends on being able to load back again, the game can suffer from issues when using savestates if you "jump back and forth in time" to before and after saving such data. If the game only saves data such as highscore data, it probably won't cause dangerous inconsistencies. So exactly how unsafe it is depends on how the game uses disk storage, and also on how savestates are used.

The only reliable solution to this is to make sure that the save states also contain complete information about data that has been changed on disk (floppy or hard). Maybe in the future (The most simple - but inefficient - implementation of this could simply make a full copy of the disks and store alongside the savestate)

18 May 2021, 22:05	#7
FrodeSolheim FS-UAE Developer Join Date: Dec 2011 Location: Førde, Norway Age: 43 Posts: 4,043	There is a reason the option is called unsafe_save_states. The save states are not safe to use in all circumstances. One particular reason is that the disk (hard or floppy) contents are not stored within the savestate. So, if data is stored back to the disk, the disk storage might get out of sync with the savestate, causing inconsistencies and data corruption. This could also happen for floppy-based games btw. If the game saves data that it later depends on being able to load back again, the game can suffer from issues when using savestates if you "jump back and forth in time" to before and after saving such data. If the game only saves data such as highscore data, it probably won't cause dangerous inconsistencies. So exactly how unsafe it is depends on how the game uses disk storage, and also on how savestates are used. The only reliable solution to this is to make sure that the save states also contain complete information about data that has been changed on disk (floppy or hard). Maybe in the future (The most simple - but inefficient - implementation of this could simply make a full copy of the disks and store alongside the savestate) Last edited by FrodeSolheim; 18 May 2021 at 22:13.