> On Jul 24, 2009, at 22:17, Bob Friesenhahn wrote: > .... > Most of the issues that I've read on this list would > have been > "solved" if there was a mechanism where the user / > sysadmin could tell > ZFS to simply go back until it found a TXG that > worked. > > The trade off is that any transactions (and their > data) after the > working one would be lost. But at least you're not > left with an un- > importable pool.
I'm curious as to why people think rolling back txgs don't come with additional costs beyond losing recent transactions. What are the odds that the data blocks that were replaced by the discarded transactions haven't been overwritten? Without a snapshot to hold the references aren't those blocks considered free and available for reuse? Don't get me wrong, I do think that rolling back to previous uberblocks should be an option v. total pool loss, but it doesn't seem like one can reliably say that their data is in some known good state. -- This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
