Let's say I've got 500GB of mail to migrate.

I don't want to create over 500GB of archived redologs while doing the migration. Is there a way not to?

Repeatedly purging redolog/archive only solves part of the problem -- presumably, the multiphase commit slows things down. Since I have copies all safe and sound on the original IMAP server, I'd be ok disabling redologs entirely. Is that how the open source edition behaves? Is there some switch that can make NE behave that way temporarily? Or does this really not create the overhead I'm assuming it does?