Hello,

I'm trying to get a couple partitions concatenated together and
am having trouble figuring out what the interleave factor should
be.  I have two 1GB IDE hard drives with identical disklabels. 
I am trying to concatenate both "e" partitions on each disk.

The ccd(4) manpage states: "the optimum interleave factor is
typically the size of a track."  This would be fine, but I'm not
really sure how to determine the size of a track.

At http://www.netbsd.org/Documentation/misc/ it states: "48
works fine for me with two disks. AFAIK with 16 and some other
numbers it can happen that all inodes will be on the same disk,
which should be avoided for performance reasons. IIRC I got some
problems, if the number of sectors of an component is not a
multiple of the interleave."

I'm not really sure what this means, either.  As you can see
from the disklabel below, the number of sectors in the component
partitions is definitely not an even number; does this mean that
I must use an interleave factor of something like 7?  I'm also
unsure why the author advises against using 16 as an interleave
factor if it's listed as an example in the ccdconfig(8)
manpage.

# disklabel wd0
type: unknown
disk: www-wd0
label:
flags:
bytes/sector: 512
sectors/track: 63
tracks/cylinder: 16
sectors/cylinder: 1008
cylinders: 2480
total sectors: 2500841
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0           # microseconds
track-to-track seek: 0  # microseconds
drivedata: 0

8 partitions:
#        size   offset    fstype   [fsize bsize   cpg]
  a:    66465       63    4.2BSD     1024  8192    16
  c:  2500778       63    unused        0     0
  d:  2500841        0    unused        0     0
  e:  2434313    66528    4.2BSD     1024  8192    16

Any insight you could provide would be greatly appreciated.

Thank you for your time,

-- 
Tyler Mitchell