Explains Sofija's OS and hardware "in-depth".
Simple language and layman's terms used when available
On a base level, Sofija has no personality - she takes in the world and reacts accordingly. Some likes and dislikes (and some political views) are pre-programmed into her, but ultimately things are only integrated into her personality if they are assigned high enough priority by Drive C. Drive A priority things include:
Many factors of her personality are highly influenceable; however, depending on the priority may have different "cement rates". Her opinion on a song may have a low cement rate, while her language skills will have a much higher cement rate that lowers over time if not maintained.
Very basic information is pre-programmed into her and may help with troubleshooting issues like drive failure. Drive A basic information includes:
Sofija's memory functions remarkably similar to a human's. New information is initially written to Drive C, and then assigned a priority between Low, Medium, and High. The higher the priority, the more likely it will be moved from Drive C to B, or maybe even A.
All of Sofija's short-term memory is stored in Drive C. Short-term Drive C memory may move to Drive B or A if assigned a higher priority. All low priority short-term information is wiped when space is needed for new information.
If assigned medium or high priority, the information will be moved from Drive C to B. Some Drive B information is eventually wiped (for instance, a task she has to complete is assigned medium priority but removed once the task is marked as complete), while most of it stays. Higher priority information (trauma, major life events, language skills) is more likely to be written into Drive A, where it will not be deleted.
Because of bitrot, Sofija is still prone to forgetting information she should know. An easy way to combat this is to routinely go over information with her (refreshing her memory). She may perform this herself by talking about past events, which may help you get a better idea of what information she is likely to forget. If a bit is flipped, it will not be lost forever; she may let you know she's forgotten the piece of information, but talking with her about it is very likely to fix it.
Low cement rate personality traits are more likely to be oversimplified and then deleted by Sofija's OS, similar to how someone may forget if they liked something or not because they haven't encountered it in years.
As Sofija's hardware ages, it's more than likely one of her drives may fail. While this fix may get harder as her hardware is considered more and more obsolete, her actual memory should not be actually damaged.
If there's a problem with Drive A, Sofija will be unable to function as she normally would, and may not respond to her environment or any input at all. While it may be frustrating to spot, she will still run and be able to balance/stand upright.
If there's a problem with Drive B, Sofija will forget any memories that aren't written to Drive A. She will revert back to recalling only the basic information pre-programmed into her, and any colloquialisms will be dropped by the OS regardless of drive priority to signal that there's an issue. Her phrasing may become more awkward and robotic because of this, and her mood may become much more neutral than normal.
Examples of out-of-character phrasing include:
Partial drive failure will usually only affect the last five years of her memory; however if the damage is bad enough, she will forget her sister, Jenny. She may recall absurd pieces of information, such as Richard Nixon being the president (who was in office the year she was created). She will recall all information in the language you ask her to - if she responds in the wrong language, there may be a problem with Drive A.
If there's a problem with Drive C, it may be almost impossible to notice - however, if you pick up on her internal sounds, it will be very easy to notice that she isn't writing any of the new information presented to her. Anything you tell her while Drive C is damaged will not be recorded to Drive B or A, and she will forget it immediately after being told.