And what about your backupPC server ? Check it for memory usage.
I fall in such problems when adding a new host with large dataset to backup (> 
100GB, all previous shares where near 10GB each) and the problem was related to 
the available RAM on my server. As it was a virtual backuppc server I increase 
the allowed memory and it solves the problem.
The symptoms were the same than yours, few cpu usage, few network bandwith used 
and very slow backup.

Patrick

Christian Völker wrote:
> Hi guys,
>
> I am using BackupPC now for years and it was always running perfectly.
> Around 25 hosts; /var/lib/BackupPC is around 2TB).
>
> Currently I am having an issue with one of my remote hosts.
>
> I even created a new instance of BackupPC to test and see what happens-
> but it is the same!
>
>
> The remote host has two share to be backed up. / with around 4GB of data
> and /srv with 27GB of data.
>
> The connection is now a 5Mbit/s (uplink) leased line with fixed IP
> (connected through OpenVPN to the BackuPC host).  The backup takes ages!
>
> When calculating with a 5Mbit/s linke 27GB should be transferred within
> ~15hours. Here, the initial full backup is not yet done and is already
> running more than 24hours!
>
> I can see some sort of progress if I do a "lsof| grep rsync" on the
> client. But it  still appears to be ways to slow! On the client "top"
> tells me 99% idle CPU (and no I/O waits). The NIC and the Internet
> connection has an outbound usage of around 350kb/s- far away from the
> 5Mbit/s the line offers.
> And yes, there is no other outbound traffic going on. I just did a
> Ms-RDP session and the line usage goes up to the expected 2.5Mbit/s!
>
> Do you have a clue why it takes to transfer?
>
> It does not seem to be linkes to a new full or incr backup- my existing
> backup server was not able to back up the machine now for 120days! Even
> though it tells me 24/7 "backup in progress".
>
> So, any idea why this performs so badly?
>
> Greetings
>
> Christian
>
>
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>


-- 
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|  Equipe M.O.S.T.         |                                      |
|  Patrick BEGOU           | mailto:Patrick.Begou AT grenoble-inp DOT fr |
|  LEGI                    |                                      |
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