> Partition size is a very different matter.  I 
  > forget the size limit of an
  > HPFS partition, but it is something like 64 GB -- extremely
  > large.

 JdBP>   2^32 sectors, or 2 Terabytes.  This is the theoretical limit of an
 JdBP>   HPFS partition.

I'm fairly sure there are other limitations.  The 64 MB limit is something
I pulled out of my head from a discussion with the person at IBM who
maintains HPFS, so I may remember that incorrectly.

There are also some problems having to do with the code below the FSD,
since the six-byte SCSI command set only supports 21-bit addresses for
logical blocks, therefore at 512 bytes per logical block you get 1 GB per
SCSI device. To get access to any more than that, you either have to fake
out the block size or use the ten-byte SCSI command set which provides
32-bit addresses for logical blocks.  However, some devices do not support
the ten-byte SCSI commands.

 JdBP>   For a full discussion, see the message that I posted in the OS2 echo
 JdBP>   on the 27th of December 1994 (It's rather long, so I'd rather not
 JdBP>   cross-post unless really necessary (-:).

I only save the last 2000 messages in OS2, so I only have them back to Jan 7.

Feel free to netmail it via Fidonet LPM, or send it via Internet to me at
.  I would be very interested in
reading it.

  > For BIOS compatibility reasons, the boot partition must

 JdBP>   It dealt with all that as well.  I think I was 
 JdBP> pretty comprehensive.  (-:

Well, that's an easy one.  :)

  >             With special remapping hardware, such as some
  > Adaptec SCSI controllers offer, you can get as much as 8 GB
  > per physical disk under DOS.

 JdBP>   It's actually an extension to the BIOS INT 13h interface that the SCSI
 JdBP>   BIOS installs.  Again, see the aforementioned post.  (-:

The Adaptec system is quite simple.  Instead of providing CHS geometry
using 63 heads and 32 sectors per track for an effective 1 MB per cylinder,
the extended mode provides CHS translation as 255 heads and 64 sectors per
track for an effective 8 MB per cylinder.  CHS is a complete ficton to a
SCSI device anyway, so the effect is transparent once OS/2 is booted.

-- Mike

--- Maximus/2 2.02