Re: [rdiff-backup-users] How to speed up rdiff-backup

[dean gaudet]

On Fri, 14 Oct 2005, Carsten Lorenz wrote:

> Since we want to backup one tera-byte of data this would last more than a 
> week.

i've never looked closely at why the first backup is so slow -- and i've 
heard the report from lots of folks... i tend to use rsync for the initial 
backup, and then use rdiff-backup with "--force" the next time (which will 
generate one increment and create the rdiff-backup-data subdirectory).

the incremental runs are a lot faster ... although i've never tried
it on a TB of data.  here are the average stats for daily backups on a
filesystem i maintain with a couple hundred mail/web accounts, with
the backup occuring over a 768k dsl line:

--------------[ Average of 31 stat files ]--------------
ElapsedTime 12966.16 (3 hours 36 minutes 6.16 seconds)
SourceFiles 1153830.35484
SourceFileSize 108174471204.0 (101 GB)
MirrorFiles 1153245.22581
MirrorFileSize 108115114552.0 (101 GB)
NewFiles 872.193548387
NewFileSize 173906366.29 (166 MB)
DeletedFiles 287.064516129
DeletedFileSize 136894182.742 (131 MB)
ChangedFiles 9703.90322581
ChangedSourceSize 9800370636.0 (9.13 GB)
ChangedMirrorSize 9778026167.13 (9.11 GB)
IncrementFiles 10880.3548387
IncrementFileSize 321359631.484 (306 MB)
TotalDestinationSizeChange 380716283.903 (363 MB)
Errors 0


> Has anyone hints how to speedup rdiff-backup?

mounting the backup filesystem noatime,nodiratime probably helps a bit.

-dean