blackmagic02881 at gmail.com
Fri Jan 4 19:41:30 GMT 2008
On Fri, 2008-01-04 at 14:12 -0500, Boris Toloknov wrote:
> Ming Zhang wrote:
> > On Thu, 2008-01-03 at 20:19 -0500, Boris Toloknov wrote:
> > > Hi,
> > > It seems that rsync transfers files whose names was changed or which
> > > were moved to another directory since the previous synchronization. I
> > > think that ability not to transfer (large) files which are present on
> > > another computer would be very helpful. Right before rsync is going to
> > > transfer some large file it could check if there some other files with
> > > the same size ( and maybe the same mtime ) on the destination
> > > computer. In case if the destination computer has such files then it
> > > could be asked to find the file with given MD5. If it's found then
> > > there is no need to transfer that file. Local copy/rename/move can be
> > > performed instead.
> > >
> > let us say you have N files in one directory and you rename the
> > directory name. so for N files, u need to check destination side all M
> > files and see if it is the renamed one. so you do NxM comparison and
> > this is not scalable at all...
> I think that a hash could be used instead of that. The destination
> computer ( at least ) must has a list of all the files in the
> destination directory. The key = size + mtime and value = pointer to
> the file entry in the list. Actually for that operation it would be
> better to have that list and hash on the sending computer.
rsync 3.0 introduce incremental scan to avoid the OOM issue, so hash
need to be optional as well... also i think this hash can be used to
detect hard link at same time. for normal use, it should be ok.
@#$%^ purging memory... (*!%
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