svn commit: r304142 - head/usr.sbin/bsdinstall/partedit

[Andriy Gapon]

On 17/08/2016 19:36, Nathan Whitehorn wrote:
> OK, so then what is the solution here? We have a number of tools that need to
> know this information: gpart, sade, bsdinstall, zfs, graid, etc. If we want to
> have a consistent set of defaults -- for example, to use 4K across the board,
> which I think is a good idea -- there should be a central place to set this that
> does not involve hacking a variety of independent tools. Do you disagree?
> 
> I don't care how that happens. It happens that the way we currently encode this
> is geom stripesize. If we feel like we can't get this right in drivers, then we
> should provide a tunable to set a minimum default alignment. You could implement
> this in lots of different ways. But having static values hardcoded in random
> places that makes similar tools (sade, gpart) behave inconsistently cannot
> possibly be the answer.
> 
> This is my point, from beginning to end. Is there any reason -- at all -- that
> we should prefer per-tool one-off changes to fixing the central mechanism we
> already have to give consistent results that we think are reliable?

It would be perfect to get a correct description of a disk and to do that in
central place.  But still I, as a user / administrator, want to be able to
_force_ the alignment that I want when I partition a disk, create a filesystem,
etc.  That is, even if the kernel reports the perfectly correct information and
the tools know how to automatically do what's best for me, I still want to eb
able to override.  And I think that installers and administrative tools should
provide a way to do that.  And many already do, e.g. 'gpart add -a X'.
So, I do not see how striving for the better disk detection (in a central place)
and having more knobs in the administration tools are mutually exclusive or
conflicting goals.

Just my two bits.
-- 
Andriy Gapon