Subject: Re: NetBSD2.0/sparc not ready for prime time?
To: None <port-sparc@NetBSD.org>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: port-sparc
Date: 02/14/2005 14:09:07
>>> The Sun disklabel is quite limited in the size of disk it can
>>> describe.
>> That is not really an issue on architectures like sun4c or sun4m,
>> which Sun itself no longer supports.
> You do care if you try to attach a new 18GB+ disk to one of these old
> machines.
I also don't think it's true.
The tracks/cylinder, sectors/track, and cylinder count values are all
16 bits, which allows describing disks as large as almost 2^48 sectors,
which is 128 petabytes. I don't think that counts as "quite limited".
(Those values are 0-65535, not 1-65536; the actual limit is 65535^3
sectors, about 127.99414+ PB.)
There is another limit, in that Sun labels have only 32 bits for
partition size in sectors and only 8 partitions, which imposes a limit
of 32GB usable space, unless you use RAW_PART - or unless you use my
patches to increase the partition count, or use the Sun label for
nothing but booting and use another label kept elsewhere for live
operation (which latter I hear NetBSD/sparc does these days).
Of course, neither of these limits prevents you from using a larger
disk; they just limit how much of its space you can use.
/~\ The ASCII der Mouse
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