--On Monday, July 19, 2004 14:07:40 -0700 Kris Vassallo <kris AT linuxcertified 
DOT com> wrote:

>   I am looking for some assistance in tweaking the bumpsize, bumpdays,
> and bumpmult items in amanda.conf. I am backing up 420GB + worth of home
> directories to hard disks every night and the backup is taking about 11
> hours. I just changed the backup of one 400GB home drive from client
> compress best to client compress fast, which did seem to shave a bit of
> time off the backup. The disks that are being backed up are on the same
> RAID controller as the backup disks.
> I really need to make the backup take a lot less time because the
> network crawls when the developers come in to work in the morning
> because the home directory server is blasting away with the backup.  So,
> with a filesystem this large, what would be some good settings for the
> bump options. Also, are there any other things I can do to get this
> backup done any faster without turning off disk compression all
> together?

Are you actually writing 420GB per night, or is that just the total
amount to be backed up?  If most of your data isn't changing daily
then breaking up your DLEs to not have a 400GB chunk could spread
the level 0s across more nights and shorten your nightly backup time.
   Are you sure its the compression using up most of the time?  You
probably need to add spindle numbers to your disklist to serialize
the accesses to the DLEs that share common disks.  Using a holding
disk not on the same controller would speed things up also.
   If your DLS and file backups share the same disks and not just
the same controller then the disks will waste quite a bit of time
seeking back and forth.  You might also want to do some performance
testing on your RAID controller, perhaps it is the bottleneck as
the model of controller (and the RAID level) can have a big impact
on throughput.
   Perhas posting your daily report and more details of the physical
layout would give us a better idea of where to start on suggestions
for improving your backup times.

Frank


-- 
Frank Smith                                      fsmith AT hoovers DOT com
Sr. Systems Administrator                       Voice: 512-374-4673
Hoover's Online                                   Fax: 512-374-4501