opinions on disk partitioning

[Leonard Lauria]

I would like to get opinions on disk configurations for a new platform.

I am installing my TSM server on an aix platform, with FASTT700 disk.

The FASTT700 has (28) 73 GB, 15K disks, of which 23 are available for this
application.
I am considering the following 2 setups, but please feel free to make other
suggestions!
1)  12 drives for the TSM DB, raid 10.  I only need 100 GB, plus room to grow,
          perhaps double, so this wastes a lot of space, but I get needed
spindles.
      Remaining 11 drives would be Raid 5, and exported as a single LUN
which would
          have 4 logical volumes for:
            570 GB disk pool
            200 GB disk pool
              20 GB disk pool
              13 GB TSM log
2)  8 drives for the TSM DB, raid 5.  I only need 100 GB, plus room to grow,
          perhaps double, so this is less space, but fewer spindles and no
mirror.
      Remaining 15 drives would be Raid 5, and exported as a single LUN
which would
          have 4 logical volumes for:
            500 GB disk pool
            500 GB disk pool
              82 GB disk pool
              13 GB TSM log
#2 gives me more spindles for the disk pools, by using only raid5 for the
database partitions.
Another concern is having the disk pools compete with each other on the
same disks.  Would
it be better to have fewer spindles per disk pools, but have disk pools
seperate from each other,
or all the disk pools spread over the same larger number of spindles?
Also, I have had a lot of conflicting information regarding TSM doing
mirrors of the DB and LOG
versus letting the FASTT hardware do raid protection.  It seems the
hardware implementation would
be faster, and just as safe, as letting TSM do mirrors...not to mention
allowing me to spread things
out a bit more.
Any opinions on my options?

Thanks!

leonard