Re: [Duplicity-talk] Backing up desktop virtual machines?

[edgar . soldin]

On 23.07.2014 03:57, Rubin Abdi wrote:
> Laurence Perkins (OE) wrote on 2014-07-22 09:52:
>> My attempts to reply to the list don't seem to be getting through, so
>> I'll send you my best guess as to the problem directly and you can
>> forward it on to the list if I am correct.
> 
> Maybe the list admin is around and will see this.

do you get error reports, the mailer refusing deliver or such?

> 
>> Duplicity only backs up changed parts of the file, but must scan the
>> entire file to determine which parts have changed.  If your .VDIs for
>> your VMs are large, this will take a while.  Try snapshotting the VMs.
>> This will cause all changes to the disks to be written to a separate,
>> potentially much smaller file.  If you snapshot after each incremental,
>> then all the changes for the VM will be in their own, small file that
>> duplicity can just pick up and add to the archive without having to scan
>> the big, unchanged root VDI.

just calculated, for 25GB to read in 1h it needs 7MB throughput. taking into 
account the first statement of 2h backup time that seems quite slow for an 
operation on a local hard drive.
 
> Thanks to both you and Edgar for pointing that out. I had no idea.
> That's kind of awesome. It now makes sense that the slow down is simply
> from Duplicity having to deal with scanning a large file in order to
> find diffs.

as stated, not sure about that.
 
..ede/duply.net