On Thu, Jul 21, 2016 at 4:34 PM, Chris Murphy <lists@xxxxxxxxxxxxxxxxx> wrote: > > Do programs have a way to communicate what portion of a data file is > modified, so that only changed blocks are COW'd? When I change a > single pixel in a 400MiB image and do a save (to overwrite the > original file), it takes just as long to overwrite as to write it out > as a new file. It'd be neat if that could be optimized but I don't see > it being the case at the moment. > NetApp has an option to do it for CIFS connections. It literally compares old and new files on renames and discards duplicates. It is off by default. I am not aware of anyone using it :) -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
