Re: GPT vs BSD-label

[Johnny Billquist <bqt%update.uu.se@localhost>]

On 2016-02-09 00:41, John Nemeth wrote:
>       Those problems could be solved.  Obviously, old tools wouldn't
> work with the new format; however, new tools could work with either
> format.  But, the first issue is that it is an on-disk format.
> You need to find the space to expand the disklabel and do so in a
> manner that doesn't break anything.  As demonstrated by OpenBSD,
> supposedly, this is possible (I have not examined it in any depth
> to assure myself that it doesn't break anything; I am simply aware
> of it).

I would actually prefer if NetBSD would do as OpenBSD, and keep and 
extend disklabels... But then again, I think I disagree with too much of 
the direction of NetBSD these days to ever think I'll be happy anyway.

>       Keep in mind, that I am definitely not an advocate of change
> for the sake of change, but if there is a need or a clear advantage
> then yes.  In this case, the need was is obvious, the limitations
> of the format bumping up against newer drives.  The other need was
> to keep up and be usable on modern PCs and certain other systems.
> Right now, most systems still have a Compatibility Support Module,
> but the day will come when you work with the modern stuff, or you
> don't work at all.

Are you essentially saying that non-modern machines (essentially non 
x86-64) are also destined to become unsupported? Are we really trying 
that much to become Linux?

>       BTW, disklabels were released with 4.3BSD-Tahoe, which was
> released in June 1988 (28 years ago).  There were plenty of versions
> of BSD prior to that which didn't support disklabel.  The first
> release of BSD was in 1977, so it took 11 years for disklabel to
> come about.  In 1988, an 80MB HD would have been huge and probably
> not available for the type of machines that BSD ran on.  With 80MB
> HDs, you would need 25,000 of them to make 2TB, which means 2TB
> was unfathomable.  Given the constraints of the time, disklabel
> was a reasonable format.  However, time tends to blow away all
> constraints.

True. Disklabels are somewhat "modern". But it's not like it was a big 
change. Before the disklabels, you had the partition table in the device 
driver, and you had details needed for creating file systems in 
/etc/dtab (I think it was). Disklabels just was a natural evolution to 
this, where you stopped having fixed partition sizes for each type of 
device. It's pretty much the same information was there before and 
after. Disklabels just moved where the information was located.

And in 1988, 80MB wasn't that big. You had way larger drives available.
RP06 was at 176MB, and was available many years before that, as was 
several other large Massbus disks. In fact, in 1988, DEC introduced the 
RA90, at 1.2G.

But yes, what seemed huge back then, are small now. So it's nothing 
strange that some fields have started to feel small...

	Johnny

--
Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt%softjar.se@localhost             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol