On Wed, 28 Feb 1996 09:48:29 -0500 
 der Mouse <mouse@Collatz.McRCIM.McGill.EDU> wrote:

 > Yes, I know why you offset by one cylinder.  What I mean is, I wish you
 > didn't have to waste a whole cylinder of space.

But, you don't *have* to ...

 > My remark was pointing out that with the current scheme, if you wish to
 > cut down on the lost space, you have to relabel the disk with a label
 > that claims smaller cylinders and more of them than the disk really
 > has.  My preferred solution would be for ccd to skip the first sector
 > (perhaps the first 8K) of a component, when that component partition
 > begins at offset zero.  I would even be satisfied if it always skipped
 > the first sector (or 8K).

When I wrote the ccd(4) manual page and said "one cylinder", that was 
meant as a guideline.  I don't particularly care if you only offset 4 
sectors ... just make sure that you don't overlap the component's 
disklabel.  You can certainly make it less than a cylinder if you wish.  
However, the guideline is written such that you're always safe at the 
cost of a few "wasted" sectors.

I.e. there is no need to fudge the cylinder size on the underlying 
components.  There is no checking within the ccd to see if you've offset 
one cylinder ... it doesn't care.

--------------------------------------------------------------------------
Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                               Home: 408.866.1912
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