Hi,

Les Mikesell wrote on 2009-08-17 16:38:23 -0500 [Re: [BackupPC-users] Is there 
a speed setting?]:
> Jeremy Mann wrote:
> > I'm watching a live output of Ganglia showing network usage while the
> > backups are going. Also simple math.. I just finished one full backup, 16
> > GB in 143 minutes. That's simply unacceptable for a full backup.

ah, so you're actually having a problem. Up to this point I wasn't sure if you
weren't just misinterpreting some figures.

> You still haven't said whether this is the first run where the files are 
> actually copied or not - if not you shouldn't expect much network 
> activity.

That is true. As has been explained, BackupPC rsync full backups read all
files on both sides but just send block checksums over the network. With
checksum caching you can cut down file reads on the BackupPC server side.

Also remember that on the first run (and whenever content is transferred that
is not yet in the pool) your data will need to be compressed. I have no idea
what the sustained compression rate of your Opteron is. Due to the way
BackupPC works, large growing (log) files may also slow things down. If that
is your problem, you might consider turning off compression (though I'm not
positive that will solve things). Also check your server status page for hash
collisions (xxx repeated files with longest chain yyy).

Finally, concurrent backups compete for disk seeks. 24 spindles sounds quite
impressive (even with RAID5 ;-), but just the same, you shouldn't be running
more than the one backup while you are trying to determine your bottleneck.

> Also, you should expect much faster rates if you have a few large files 
> than if you have millions of tiny ones.

Can you give us any information on that (file count, average file size)?

Regards,
Holger

------------------------------------------------------------------------------
Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day 
trial. Simplify your report design, integration and deployment - and focus on 
what you do best, core application coding. Discover what's new with 
Crystal Reports now.  http://p.sf.net/sfu/bobj-july
_______________________________________________
BackupPC-users mailing list
BackupPC-users AT lists.sourceforge DOT net
List:    https://lists.sourceforge.net/lists/listinfo/backuppc-users
Wiki:    http://backuppc.wiki.sourceforge.net
Project: http://backuppc.sourceforge.net/