parallel tree recursion

[Wayne Davison]

On Fri, Dec 02, 2005 at 05:29:32PM -0600, Phil Howard wrote:
> How hard would it be to have rsync do the file recursion scan on both the
> source tree and the destination tree at the same time in parallel?  Would
> that require a protocol change, or could just a program change be enough?

It might be possible to have rsync stat all the files as they arrive
from the sender and mark the changed ones using flags, but it is unclear
how much of a time savings that would be since rsync would still need to
wait until all the file list arrived before starting to transfer files
and make changes (it might be able to create directories, symlinks, and
devices during this time, but that would require a protocol bump due to
how rsync currently reports these events).  It would be interesting to
do some tests and see if it helps.

What I'd like to do with rsync in the long run is to have it begin
transferring each directory just after it is scanned, but that will
require a protocol bump and a lot of changes to how rsync works.  I
have some ideas on how this might be implemented, and will hopefully
be able to look into this soon.

..wayne..