[CentOS] unison versus rsync

Thu Jan 14 00:01:11 UTC 2010
Brian Mathis <brian.mathis at gmail.com>

On Wed, Jan 13, 2010 at 6:54 PM, Joseph L. Casale
<jcasale at activenetwerx.com> wrote:
> Anyone got any actual comparisons between unison and rsync specifically related
> to the performance of synchronization of large data sets over slow links?
>
> I have a huge tree to start replication of Friday and know that if I sync the root
> paths it will take ages and with the lack of any overall state of progress this won't
> be optimal as its likely to fail for whatever reason before it can finish. Initially
> I just thought I would break it down to several smaller jobs but that becomes a burden
> to maintain...
>
> We use bacula internally  but sending the diffs would be cumbersome as the individual
> files would be rather large...
>
> Thanks!
> jlc

Use rsync.  It's used far more than unison, so it has been tested
better.  Unison has always been slow for me.

One thing you might want to look at is performing the initial copy, or
some chunks of it, using tar over a netcat link, then rsync after
that.  Since rsync uses SSH, it can be 33% slower than a pure data
transfer connection.  Using netcat won't get you encryption though, so
make sure you're on a local/trusted link.