even modern scsi disks have such a concept, and they make very good use 
of it in disk firmware when scheduling operations.. 
and even outside of disk firware, being aware of tracks is both possible 
and useful.. check out http://www.pdl.cmu.edu/Freeblock and 
http://www.pdl.cmu.edu/Dixtrac.. the track-aligned extents stuff isn't online
atm it seems.. 
now, ide disks are _way_ worse at trying to present the disk as an 
abstract vector of blocks with no performance impact from particular 
access patterns... 
Isildur

On 14 May 2002, Perry E. Metzger wrote:

> 
> On Mon, May 13, 2002 at 11:51:52PM -0400, Lord Isildur wrote:
> > for example, one of the very cheap things with a pretty good win is to 
> > avoid allocating blocks which span track boundaries, as a quick way to 
> 
> Haven't seen a disk where you had any idea what a "track" actually was
> in years. I suppose "Lord Isildur" doesn't know about ZBR.
> 
> For reference, on modern drives, "geometry" is entirely a fiction.
> 
> --
> Perry E. Metzger		perry@wasabisystems.com
> --
> NetBSD: The right OS for your embedded design. http://www.wasabisystems.com/
>