Rsync 4TB datafiles...?

[Paul Slootman]

On Wed 22 Mar 2006, Linus Hicks wrote:
> Paul Slootman wrote:
> >
> >I'd recommend doing --inplace, as chances are that data won't move
> >within a file with oracle data files (so it's not useful to try to find
> >moved data), and copying the 4TB to temp. files every time could become
> >a big timewaster. Also the -t option could be handy, not all files
> >change all the time IIRC.
> 
> The above remark about not being "useful to try to find moved data" 
> provoked an idea. But my understanding of --inplace is apparently different 
> from yours. I thought --inplace only meant that the destination file would 
> be directly overwritten, not that it would turn off any of the 
> optimizations for finding moved data.

I go on what's in the manpage:

 --inplace
    This causes rsync not to create a new copy of the file and then move  it
    into  place.   Instead  rsync  will overwrite the existing file, meaning
    that the rsync algorithm can't accomplish the  full  amount  of  network
    reduction  it  might  be able to otherwise (since it does not yet try to
    sort data matches).  One exception to this is if you combine the  option
    with --backup, since rsync is smart enough to use the backup file as the
    basis file for the transfer.


Paul Slootman