I noticed (from experimentation and documentation) that the chunker overlay's chunking procedure will stream the upload of a modified file into the remote. For an existing chunked file, this can create a massive re-uploads of chunks which may never have been modified.
For checksum-enabled remotes, it would be neat if chunker would offer a flag/option to use chunk checksums to only reupload chunks which have been modified. This could save a lot of time and bandwidth by cutting down on the total number of chunk files rclone will have to write to a remote.
The example use case is to use rclone to efficiently re-upload modified disk image files by only uploading the individual chunks which were modified.
rclone sync has the option to use the --checksum flag to only upload files which were modified - and it works great! Could this idea be expanded to chunks? It would be awesome if a mounted chunker remote can leverage a similar checksum-based chunk upload to only upload the modified/updated chunks.
Would a feature like this be technically possible? Are there any obvious hurdles that would need to be overcome for a feature like this?