Re: amd64 as default architecture
On Sun, May 20, 2012 at 02:00:21PM +0100, Ben Hutchings wrote:
> On Sun, 2012-05-20 at 11:27 +0200, Goswin von Brederlow wrote:
> > Ben Hutchings <ben@decadent.org.uk> writes:
> >
> > > Most new PCs have an Intel or AMD 64-bit processor, and
> > > popcon.debian.org shows amd64 numbers almost matching i386.
> > >
> > > For some time we have also provided the amd64 kernel for i386, identical
> > > in all but the package metadata. This has not always been perfectly
> > > compatible with i386 userland, but split 32/64-bit installations are
> > > increasingly used and I think most bugs have been flushed out by now.
> > > Thanks to multi-arch you can now add amd64 as a secondary architecture
> > > and install the kernel package from amd64, and if your system is running
> > > such a kernel then it can also support userland packages from amd64.
> > >
> > > So in wheezy I would like to see:
> > > 1. Default architecture (top of the list for installation media/manual)
> > > being amd64 ('64-bit PC').
> >
> > Default image could be multiple archs. We had i386/amd64/ppc DVD images
> > in the past and that seems like the best default. It simply works (near
> > enough) everywhere. Doesn't work for all image types but where it does ...
>
> The default image *is* i386/amd64 netinst.
>
> > > 2. Users of the amd64 kernel flavour on i386 encouraged to add amd64 as
> > > a secondary architecture (debconf note?).
> >
> > 2b. Have D-I ask wether to enable multiarch on amd64 on i386 if it
> > installed the amd64 kernel image but also i386 on amd64.
>
> Would be good, but might not be possible in time for wheezy.
>
> > Slightly OT but I wanted to mention it for its similarity:
> >
> > One thing that should be tested and then documented prominently as yay
> > or nay in the wheezy upgrade notes is wether one can cross-grade from
> > i386 to amd64 using multiarch. Wether one can install apt/dpkg:amd64 and
> > then migrate to a 64bit userspace.
>
> I don't believe this is easily doable yet. (It was possible, with
> difficulty, even before multi-arch.)
>
> > > Then in wheezy+1:
> > > 3. amd64 kernel flavour for i386 dropped.
> > > 4. Kernel and common libraries for amd64 included in i386 installation
> > > media; kernel included on low-number disc.
> > > 5. Installer for i386 prefers amd64 kernel on any capable machine
> > > (that's a one-line change!) and adds amd64 as secondary architecture if
> > > this is selected.
> >
> > D-I (libdebian-installer) must be multiarch aware for that then.
> > Otherwise it won't see the amd64 kernel in the first place.
>
> Yes.
>
> > > Eventually (wheezy+2? +3?) we would stop building a kernel package for
> > > i386.
> >
> > As in drop the i386 arch?
>
> No, keep i386 userland only. Though we might consider reducing even
> that to a 'partial architecture' that has only libraries (similar to
> ia32-libs today, only cleaner).
How would plain x86 systems be supposed to boot, then?
Mike
Reply to: