Hi,
I've been happy using duplicity to backup my Ubuntu PC to my NAS for around 18 months now, using rsync.
I do a full back up every 2 weeks, and and incremental daily.
I noticed in August that the full backup started taking around twice as long, from
--------------[ Backup Statistics ]--------------
StartTime 1502355166.95 (Thu Aug 10 09:52:46 2017)
EndTime 1502373067.73 (Thu Aug 10 14:51:07 2017)
ElapsedTime 17900.78 (4 hours 58 minutes 20.78 seconds)
SourceFiles 1361618
SourceFileSize 212181777813 (198 GB)
NewFiles 1361618
NewFileSize 212181777813 (198 GB)
DeletedFiles 0
ChangedFiles 0
ChangedFileSize 0 (0 bytes)
ChangedDeltaSize 0 (0 bytes)
DeltaEntries 1361618
RawDeltaSize 211041882531 (197 GB)
TotalDestinationSizeChange 166597720163 (155 GB)
Errors 0
-------------------------------------------------
to
--------------[ Backup Statistics ]--------------
StartTime 1503684459.99 (Fri Aug 25 19:07:39 2017)
EndTime 1503718307.60 (Sat Aug 26 04:31:47 2017)
ElapsedTime 33847.61 (9 hours 24 minutes 7.61 seconds)
SourceFiles 1361798
SourceFileSize 212042512113 (197 GB)
NewFiles 1361798
NewFileSize 212042512113 (197 GB)
DeletedFiles 0
ChangedFiles 0
ChangedFileSize 0 (0 bytes)
ChangedDeltaSize 0 (0 bytes)
DeltaEntries 1361798
RawDeltaSize 210902807446 (196 GB)
TotalDestinationSizeChange 166567853868 (155 GB)
Errors 0
-------------------------------------------------
As you can see, pretty much the same statistics except for the time taken.
Now in between these 2 full backups, probably the most significant change to my system was an upgrade from Ubuntu 16.10 to 17.04.
I don't think network speed is an issue because some of the (4GB) vol files can take as little as 5 minutes (looking at the timestamps) which I assume includes creation and transfer time.
I've noticed that the slowest archive files to be produced took around 1h 25m, and either consisted of lots and lots of small files, or very large binary files.
Is anyone aware of any change in the versions of the Ubuntu packages that duplicity relies on, between Ubuntu 16.10 and 17.04 that might have caused this slowdown?
I haven't looked yet at adding extra logging to help see if my thoughts on creation vs transfer time are correct.
On the plus side, this has nudged me to look more closely at what unnecessary cruft I'm backing up :D
Many thanks, and best regards,
Matthew.