On Wed, Dec 12, 2012 at 04:57:38PM +0100, Benoît Canet wrote: > > Can you foresee the need to use a different hash algorithm in the future > > and should we add a hash_algo enum field to the dedup QCOW2 header > > extension? > > Yes I foresee the future use of faster hash function like SHA3 or Skein. > > I also think an alternate deduplication mechanism where lookups are done > on disk in order to be able to deduplicate very large volume could be added. > > What would be the cleanest way to store this in the header extension ? > bitmaps or two char fields ?
The header extension could have a uint8_t hash_algo field (and 3 reserved bytes that can be used in the future). 0 - SHA256 1 - Skein ... Stefan
