Nathan Kroenert <[EMAIL PROTECTED]> writes: > Bob Friesenhahn wrote: >> On Tue, 4 Mar 2008, Nathan Kroenert wrote: >>> >>> It does seem that some of us are getting a little caught up in disks >>> and their magnificence in what they write to the platter and read >>> back, and overlooking the potential value of a simple (though >>> potentially computationally expensive) circus trick, which might, just >>> might, make your broken 1TB archive useful again... >> >> The circus trick can be handled via a user-contributed utility. In >> fact, people can compete with their various repair utilities. There are >> only 1048576 1-bit permuations to try, and then the various two-bit >> permutations can be tried. > > That does not sound 'easy', and I consider that ZFS should be... :) and > IMO it's something that should really be built in, not attacked with an > addon. > > I had (as did Jeff in his initial response) considered that we only need > to actually try to flip 128KB worth of bits once... That many flips > means that we in a way 'processing' some 128GB in the worse case when > re-generating checksums. Internal to a CPU, depending on Cache > Aliasing, competing workloads, threadedness, etc, this could be > dramatically variable... something I guess the ZFS team would want to > keep out of the 'standard' filesystem operation... hm. :\
Maybe an option to scrub... something that says "work on bitflips for bad blocks", or "work on bitflips for bad blocks in this file" Boyd _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
