None so long as everyone's just reading. If anyone wants to write and tries to get an exclusive lock, they'll have to wait for everyone to finish reading and untie, but that's the point of the excercise: it guarantees that you can never end up writing back out of date data. Of course you'll have to tell your users that they need to untie and forget what they've read as soon as possible, if many processes are to be simultaneously writing to that same database.

Makeshifts last the longest.

In reply to Re^3: Locking and synchronisation within tied hashes by Aristotle
in thread Locking and synchronisation within tied hashes by rob_au

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