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Questions about software RAID level 1 (how long should it take to sync, etc?)

I'm in the process of setting up a software RAID level 1 on debian
testing with two 160 gig drives on an Asus P4P800 motherboard with
Intel Pentium 4 CPU 3.00GHz and 512 megs of RAM.  I've been following
the instructions in /usr/share/doc/mdadm/rootraiddoc.97.html and have
just issued the command "mdadm --add /dev/md0 /dev/hda1" to add my
original debian installation to the RAID array (after already having
copied the contents of hda1 to hdc1, and then rebooting from hdc1). 
When I cat /proc/mdstat, I get the following:

[>....................]  recovery =  4.9% (7907776/158577472)
finish=1533.5min speed=1636K/sec

I'm curious about a few things:

1) does 25 hours seem like a reasonable amount of time for an initial
synchronization of two 160 gig drives?

2) would using a hardware card (such as a 3ware 7006-2 Parallel ATA
RAID Controller) decrease the amount of time to sync?

3) will it take this long to synchronize the drives after, say, a
system crash (ie a hard reboot), or does it only take 25 hours for the
initial sync ?

4) If I do decide to switch to hardware RAID, will I be able to use
the same drives without a large configuration/resyncrhonization

5) if hda1 contained the original root system, and hdc1 is simply a
copy of it (ie the drives are a mirror), why is it taking 25 hours to
"synchronize" the drives, aren't they already sync'd?  Shouldn't this
be a much faster process?

Any help or suggestions are very much appreciated.  Thanks!


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