On Tue, Jan 29, 2013 at 12:56 PM, Arun C Murthy <a...@hortonworks.com> wrote:
> Folks,
>
> There has been some discussions about incompatible changes in the
> hadoop-2.x.x-alpha releases on HADOOP-9070, HADOOP-9151, HADOOP-9192 and
> few other jiras. Frankly, I'm surprised about some of them since the
> 'alpha' moniker was precisely to harden apis by changing them if necessary,
> borne out by the fact that every single release in hadoop-2 chain has had
> incompatible changes. This happened since we were releasing early, moving
> fast and breaking things. Furthermore, we'll have more in future as move
> towards stability of hadoop-2 similar to HDFS-4362, HDFS-4364 et al in HDFS
> and YARN-142 (api changes) for YARN.
>
> So, rather than debate more, I had a brief chat with Suresh and Todd.
> Todd suggested calling the next release as hadoop-2.1.0-alpha to indicate
> the incompatibility a little better. This makes sense to me, as long as we
> are clear that we won't make any further *feature* releases in hadoop-2.0.x
> series (obviously we might be forced to do security/bug-fix release).
>
> Going forward, I'd like to start locking down apis/protocols for a 'beta'
> release. This way we'll have one *final* opportunity post
> hadoop-2.1.0-alpha to make incompatible changes if necessary and we can
> call it hadoop-2.2.0-beta.
>
> Post hadoop-2.2.0-beta we *should* lock down and not allow incompatible
> changes. This will allow us to go on to a hadoop-2.3.0 as a GA release.
> This forces us to do a real effort on making sure we lock down for
> hadoop-2.2.0-beta.
>
> In summary:
> # I plan to now release hadoop-2.1.0-alpha (this week).
> # We make a real effort to lock down apis/protocols and release
> hadoop-2.2.0-beta, say in March.
> # Post 'beta' release hadoop-2.3.0 as 'stable' sometime in May.
>
> I'll start a separate thread on 'locking protocols' w.r.t
> client-protocols v/s internal protocols (to facilitate rolling upgrades
> etc.), let's discuss this one separately.
>
> Makes sense?
No.
I find the above opaque and written in a cryptic language that I might grok
if I spent a day or two running over cited issues trying to make some
distillation of the esotericia debated therein. If you want feedback from
other than the cognescenti, I would suggest a better summation of what all
is involved. I think jargon is fine for arcane technical discussion but it
seems we are talking basic hadoop versioning here and if I am following at
all, we are talking about possibly breaking API (?) and even wire protocol
inside a major version: i.e. between 2.0.x to 2.3.x say (give or take an
-alpha or -beta suffix thrown in here and there). Does this have to be?
Can't we do API changes and wire protocol change off in hadoop 3.x and
4.x, etc. As is, how is a little ol' downstream project like the one I
work on supposed to cope w/ this plethora of 2.X.X-{alpha,beta,?} with no
each new 2.x possibly a whole new 'experience'?
Thanks Arun,
St.Ack
