[CentOS] variable raid1 rebuild speed?

>> Ummmm.... RAID is not a backup policy. Fine use hotswap and rsync or
>> similar but you
>> really shouldn't be relying on raid rebuilds for that.
> These are backups to begin with.  It is the archive disk for backuppc which
> contains millions of hardlinked files for the de-duplication it uses. It would
Ouch! I understand now. Backuppc does leave an unholy mess of the 
filesystem. Using RAID
isn't a good solution but I guess is almost the only one that works.