|You can see that this would cause all the subsequent blocks to be shifted forward or backwards – so all the column checksums, and all the row checksums below this point, would be wrong.
Ahh! Bugger. ; )
you would need constant communications to determine which block to checksum next
What a hairy problem. I see what you mean now. It’s a shame rsync uses so much memory for the sums.
Thanks for the explanation.
Maybe a slightly smarter apt-get that could request diffs of previous full files is the answer for speeding up system updates?