Re: [Qemu-devel] [PATCH] hw/i386: Deprecate the machines pc-0.10 to pc-0.15

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Markus Armbruster (armbru@redhat.com) wrote:
> Thomas Huth <thuth@redhat.com> writes:
> 
> > On 10.05.2017 11:08, Daniel P. Berrange wrote:
> >> On Wed, May 10, 2017 at 08:48:53AM +0200, Thomas Huth wrote:
> [...]
> >> Also unless we're going to get more serious about automated testing to
> >> validate machine type compatibility between *all* previously releases,
> >> I think that 6 years / 18 releases is too long a time to have any
> >> confidence in migration compatibility between versions.
> 
> Seconded.
> 
> > Distro vendors often offer 5 - 10 years support for certain versions of
> > their Linux distros, so I think we should at least support 5 years, too.
> 
> Non sequitur.
> 
> Distro vendors put in serious work to keep versions working for 5 - 10
> years.  We can't, and we don't.  All we do is try not to break things,
> which is nice, and helps the distro vendors some, but a far cry from
> anything I'd dare call "support".
> 
> Perhaps an argument could be made that us keeping to try for at least 5
> years would help distro vendors enough to be worthwhile.  Maybe, but
> color me skeptic.

Since I'm often the one having to fix the breakages when we find they've
diverged, I would prefer us to try to keep them working upstream.
Every time something slips through upstream it's more work for me.

Dave

> >> IOW, I think you should be more aggressive in culling old machine types
> >> that this patch is...
> >
> > Actually, I like the idea of using the major release versions for
> > defining the set of removal - hoping that we will do a v3.0 next year
> > which then would support the previous two major release versions 1.x and
> > 2.x, but drops support for the 0.xx versions completely ...
> 
> I wouldn't put *that* much weight into our past version numbers.  If I
> remember correctly, there was no more to 1.0 than a feeling of "this 0.x
> thing is getting ridiculous".
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK