On Mon, Nov 24, 2014 at 03:07:45PM -0500, Chris Mason wrote: > On Mon, Nov 24, 2014 at 12:23 AM, Liu Bo <bo.li....@oracle.com> wrote: > > This brings a strong-but-slow checksum algorithm, sha256. > > > > Actually btrfs used sha256 at the early time, but then moved to > > crc32c for > > performance purposes. > > > > As crc32c is sort of weak due to its hash collision issue, we need a > > stronger > > algorithm as an alternative. > > > > Users can choose sha256 from mkfs.btrfs via > > > > $ mkfs.btrfs -C 256 /device > > Agree with others about -C 256...-C sha256 is only three letters more ;) > > What's the target for this mode? Are we trying to find evil people > scribbling on the drive, or are we trying to find bad hardware?
We could provide an interface for external applications that would make use of the strong checksums. Eg. external dedup, integrity db. The benefit here is that the checksum is always up to date, so there's no need to compute the checksums again. At the obvious cost. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
