Re: [Ksummit-discuss] [CORE TOPIC] stable issues

[Takashi Iwai <tiwai@suse.de>]

At Mon, 5 May 2014 09:41:26 -0400,
Theodore Ts'o wrote:
1> 
> On Mon, May 05, 2014 at 10:47:55AM +0800, Li Zefan wrote:
> > 
> > Yeah, but we can't expect other maintainers to do this. As Greg has been
> > emphasizing, we'd want to add as little burden as possible for subsystem
> > maintainers. With this in mind, focusing on fewer LTS kernels might make
> > sense?
> 
> An LTS kernel becomes important when distributions or manufacturers
> need to depend on one for their stable/enterprise distribution or for
> some product release.  The problem comes when a stable kernel such as
> 3.10 gets declared, but some feature which is badly needed doesn't
> make it into 3.11, say, or at the time when 3.10 gets declared, some
> internal team had already decided to use 3.11.
> 
> So what might help is if companies or distributions who need a LTS
> kernel were willing to disclose that fact ahead of time, and see if
> they can find like-minded associates who also might need a LTS kernel
> around about the same time.  Obviously if a company is willing to
> dedicate resources to maintaining the LTS kernel they should have a
> bit more say about which LTS kernel they would be willing to support.
> 
> I am aware of companies or distributions which are using 3.10, 3.11,
> and 3.12 (yes, all three!) for different long-term product/production
> kernels.  The company that used 3.11 didn't talk to anyone externally
> before selecting 3.11, and so it's only right that this company live
> with the consequences of that particular engineering decision.  But
> yeah, with a bit of communication, I suspect it could have resulted in
> a bit less work all around.
> 
> The challenge is that companies generally need to be able to make that
> decision at least 3-6 months ahead of time for planning purposes, and
> this requires that companies be willing to actually communicate their
> stablization plans externally ahead of time.  Which, unfortuantely,
> may or may not always be practical.
> 
> And of course, depending on how many patches get integrated into said
> "enterprise" kernel, it might end up being very far from the official
> upstream stable kernel, so it might or might not matter in any case.

Or, other way round: can the upstream LTS kernel be defined earlier?
Then distros may align to it when it's known beforehand.
It'd be even helpful for subsystem maintainers to decide whether some
big infrastructure change should be applied or postponed.


Takashi