Stephan Szabo <[EMAIL PROTECTED]> writes: > Right, but since the how to resolve it currently involves executing a > query, simply stopping dead won't allow you to resolve it. Also, if we > stop at the exact wraparound point, can we run into problems actually > trying to do the vacuum if that's still the resolution technique?
We'd have to do something with a fair amount of slop. The idea I was toying with just now involved a forcible shutdown once we get within say 100,000 transactions of a wrap failure; but apply this check only when in interactive operation. This would allow the DBA to perform the needed VACUUMing manually in a standalone backend. The real question here is exactly how large a cluestick do you want to hit the DBA with. I don't think we can "guarantee" no data loss with anything less than forced shutdown, but that's not so much a cluestick as a clue howitzer. Maybe (a) within 200,000 transactions of wrap, every transaction start delivers a WARNING message; (b) within 100,000 transactions, forced shutdown as above. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 9: the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match