Anyway, is the 6.3GB ONLY the database data students and users? Or does it contain the operating system and supporting software (apache python, mysql binaries etc). To estimate space, I normally let the product run for several months and check daily/monthly usage. You might find that in April/August (school holidays) the data doesn't expand that much.
If your DB is structured correctly, space usage should be inversely exponential for a selected client base (master tables) from what I've seen of transactional systems (telecoms and banks)
If I were you, I'd watch for some time,graph then estimate
Centi zangu mbili
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