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Date: Fri, 26 May 1995 10:59:22 +1000
From: Bruce Evans <bde@zeta.org.au>
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To: bde@zeta.org.au, terry@cs.weber.edu
Subject: Re: newfs weirdness...
Cc: FreeBSD.org!current@sbstark.cs.sunysb.edu,
        blaise.ibp.fr!roberto@sbstark.cs.sunysb.edu,
        cs.weber.edu!terry@sbstark.cs.sunysb.edu, gene@starkhome.cs.sunysb.edu,
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>> It's better because 4096 is larger than the average fake cylinder.  (This
>> will probably change when disks get larger - all disks will have 1024
>> heads, 256 sectors and 63 sectors; larger disks will be unstriped and
>> everyone will complain about the 8GB limit :-]).

>Maybe on FreeBSD; not on Windows 95.  Windows 95 has support for a minimum
>64G of disk (using 4k sectors instead of 512 byte sectors).

FreeBSD has support for a minumum of 1024G of disk (using 512 byte sectors
and 31 bit sector numbers).

>There is further support  in the IOS for 64 bit (unsigned) offsets.

FreeBSD only supports 63 bit file system offsets.  Files larger than 2GB
and mmapping at offsets larger than 2GB are currently broken.  mmapping
of objects larger than 4G cannot work with the current interfaces.

>BTW, I have seen a working 100G SCSI device used on an ICON system
>(a pretty old 88k box), so the limits aren't inherent there, either
>(one wonders where the 8G limit in FreeBSD comes from).

It is a BIOS/partition table limit.  How do you boot from partitions
beyond the 8G boundary? :-)

Bruce