hadoop-yarn-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Karthik Kambatla <ka...@cloudera.com>
Subject Re: [DISCUSS] Developing features in branches
Date Thu, 30 Apr 2015 18:06:38 GMT
Thanks Bikas. Inline.

On Thu, Apr 30, 2015 at 10:12 AM, Bikas Saha <bikas@hortonworks.com> wrote:

> IMO,
>
> Branch development is great when the feature is "blue sky" - we don't
> exactly know what we are going to do. We will try out things and the
> current state will be unstable for a while until we have figured things out.
>
> On master, the work would be clearly spec'd out and done without causing
> disruption. So I am guessing, branches could be used when the feature is
> expected to be more "blue sky". Of course that's a subjective call.
>

IMO "Blue sky" features absolutely need to be developed in branches.

Even for features with clear specs, if they have multiple commits and take
several months, I believe they could use branches to make sure they don't
leak partial states into release branches.

I didn't want to bring up specific features that got into releases
half-baked, but we have had a few that don't work with RM restart or
security or even lack documentation. Given we don't (yet) have a formal way
to label releases alpha or beta in, developing in branches would save us
the embarrassment of shipping something that is not ready.

And, as soon as we think it is ready for wider consumption, would could
merge in milestones.


>
> Bikas
>
> -----Original Message-----
> From: Zhijie Shen [mailto:zshen@hortonworks.com]
> Sent: Wednesday, April 29, 2015 9:43 PM
> To: yarn-dev@hadoop.apache.org
> Subject: Re: [DISCUSS] Developing features in branches
>
> My 2 cents:
>
> Branch maintenance cost should be fine if we have few features to be
> developed in branches. However, if there're too many, each other branch may
> be blind to most of latest code change from others, and trunk/branch-2
> becomes stale. That said, with the increasing adopting of branch
> development, it's likely to increase the cost of merging each branch back.
>
> Some features may last more than one releases, such as RM restarting
> before and timeline service now. Even if it's developed in a branch, we may
> want to merge its milestones such as phase 1, phase 2 back to
> trunk/branch-2 to align with some release before it's completely done.
> Moreover, my experience is that the longer a feature stays in the branch,
> the more conflicts we have to merge. Hence, it may not be a good idea to
> hold a feature in the branch too long before merging it back.
>
> Thanks,
> Zhijie
> ________________________________________
> From: Subramaniam V K <subru.vk@gmail.com>
> Sent: Wednesday, April 29, 2015 7:16 PM
> To: yarn-dev@hadoop.apache.org
> Subject: Re: [DISCUSS] Developing features in branches
>
> Karthik, thanks for starting the thread.
>
> Here's my $0.02 based on the experience of working on a feature branch
> while adding reservations (YARN-1051).
>
> Overall a +1 for the approach.
>
> The couple of pain points we faced were:
> 1) Merge cost with trunk
> 2) Lack of CI in the feature branch
>
> The migration to git & keeping the feature branch in continuous sync with
> trunk mitigated (1) and with Allen's new test-patch.sh addressing (2),
> branches for features especially if used for all major features seems like
> an excellent choice.
>
> -Subru
>
> On Tue, Apr 28, 2015 at 5:47 PM, Sangjin Lee <sjlee0@gmail.com> wrote:
>
> > Ah, I missed that part (obviously). Fantastic!
> >
> > On Tue, Apr 28, 2015 at 5:31 PM, Sean Busbey <busbey@cloudera.com>
> wrote:
> >
> > > On Apr 28, 2015 5:59 PM, "Sangjin Lee" <sjlee0@gmail.com> wrote:
> > > >
> > >
> > > > That said, in a way we're deferring the cost of cleaning things up
> > > towards
> > > > the end of the branch. For example, we don't get the same
> > > > treatment of
> > > the
> > > > hadoop jenkins in a branch development. It's left up to the group
> > > > or
> > the
> > > > individuals to make sure to run test-patch.sh to ensure tech debt
> > > > does
> > > not
> > > > accumulate.
> > >
> > > As Allen previously mentioned, the QA bot will run test-patch
> > > against feature branches so long as you name the patch file correctly.
> > >
> >
>



-- 
Karthik Kambatla
Software Engineer, Cloudera Inc.
--------------------------------------------
http://five.sentenc.es

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message