rsync rewrites all blocks of large files although it uses delta transfer

[Paul Slootman]

On Thu 14 Feb 2019, Delian Krustev via rsync wrote:
> On Wednesday, February 13, 2019 6:25:59 PM EET Remi Gauvin 
> <remi at georgianit.com> wrote:
> > If the --inplace delta is as large as the filesize, then the
> > structure/location of the data has changed enough that the whole file
> > would have to be written out in any case.
> 
> This is not the case.
> If you see my original post you would have noticed that the delta transfer 
> finds only about 20 MB of differences within the almost 2G datafile.

I think you're missing the point of Remi's message.

Say the original file is:

ABCDEFGHIJ

The new file is:

XABCDEFGHI

Then the delta is just 10%, but the entire file needs to be rewritten as
the structure is changed.


Paul