Text, binary, it's all the same to gbak.   Try the -g suggestion - if gbak is cleaning out garbage, it's slow.

But, surely, the garbage has to be cleaned out sooner or later, and doing it in a backup run is the cheapest way to do it, as every record is being visited anyway? (Compared to, say, doing a COUNT(*) to clean garbage, which will visit records it doesn't need to, or, worst of all, letting the cost land at random on whichever poor sod next does a query on the table with the garbage.)

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Tim Ward