[RFC] Remove requirement of alignment to track from MBR scheme

[Andriy Gapon]

on 23/05/2011 20:38 Warner Losh said the following:
> 
> On May 23, 2011, at 10:35 AM, Marcel Moolenaar wrote:
>> I think we've had enough rushed and ill thought-out changes going
>> in already and I can see that not aligning MBR partitions on a track
>> boundary is potentially perceived as a PITA violation.

_PITA_ violation? :-)
As to POLA - yeah, I can see people getting astonished that finally FreeBSD got
its sh*t together and did the right thing, years after all other OSes (even
Winddows) had done it.

> I can understand only generating MBRs on a track boundary.

No.  E.g. I wanted to create a 4KB aligned MBR slice, but our tools insisted on
using a 63 sector alignment.  In fact, the value that I provided was silently
rounded to the value that gpart thought was best for me.
Really, if a user says to gpart "do whatever alignment you want", then I could
see using geometry-based values, but I still think that we should not do that
even in that case, I think we would be better off using some nice 2^N alignment.
If a user says "use this alignment or slice start", then the tool should just
shut up and do exactly what the user told it.

This is _not_ just my 2 cents :-)
-- 
Andriy Gapon