reducing file list bytes transferred

Peter Salameh psalameh at
Tue Oct 2 04:11:13 GMT 2007

Thanks for that.  Doesn't the delta-transfer algorithm compare the files
on sender and receiver?  For the file list, we would only need compare the
new file list with the last one on the sender (it would be a simple matter
to check that the receiver's file list is still valid with a checksum).

If the same rsync command is done over and over on a huge number of files,
then a command like --save_list=path/filename could be used specify where
to store the list (on both ends).  The delta-transfer algorithm (or some
difference code specific to the file lists) could be used on the sender to
find differences between the new list and the saved list.

After reading the chain you referenced, I realized that the rsync command
should be identical (no change in options) for this to work without
side-effects, since I infer that the file list generated depends on the
options.  One possibility is to store the rsync command used to generate
the list along with the saved list, to check that the list is still valid.

I'm sure there are many rsync users out there who would benefit from this.
 Still rsync is greatly appreciated.


> On 10/1/07, Peter Salameh <psalameh at> wrote:
>> Has the rsync team considered an rsync option which would remember the
>> last file list on both ends, and only send changes to the list?
> Perhaps a more natural approach is to use the delta-transfer algorithm
> to send the file list.  Jamie Lokier suggested this approach here:
> Matt

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