Definitely go with a real SQL server like MySQL. For your intentions, this file-based DB is simply not extensible enough. The standard DBFile engines have a pretty much similar routine: tie the file in, read and write hashes loading them on demand with zero amortization- that means, while they are simple to set up and use, their use really burns out at more than a few users, especially since no more than one user can access the DBFile at a time! (As far as I know, none of them implement record locking.) I see this as as a case of "I see no choice but to upgrade my existing systems to something that will be scalable enough to handle the load." Good luck!

Update: Yes, tilly. Very good, tilly. Next time read the main node and make sure that what you say is relevant- e.g. ala GDBM.

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