+1 on we would prefer more to using feature branches on big efforts. Thanks Colin for the insights and details. For better effect and to make feature branch more attractive, we might also consider to give more love to such feature branches, maybe not so much as we do to trunk. In this thinking, the creation of a feature branch would be notified in the mailing list documenting the proposed change, impact, timeline schedule and etc. for broad attentions. Potential reviewers are encouraged to participate in the development discussions from beginning or earlier to make later merge vote easier to pass.
+1 on we should be more respectful. Contributing is already hard enough. Working on Hadoop should be more fun. Is contribution to Hadoop still a very cool thing as it was some time before say 5 years ago? The community should be more united and work together more efficiently on the major things, for example Hadoop 3.0 release, EC, Ozone and this HDFS async support, to make these wonderful features be available to users as earlier as possible. It's fast evolving, users can't wait too long. +1 on we should avoid reverting back and forth. It looks rather messy. I think this was just a special case. Since it was mentioned, regarding Hadoop 3.0 alpha/beta releases on trunk, the process was discussed before, the progress looks fine and the first release cut is promising, thanks to Andrew and many other guys working on that. If we do big changes on feature branch and merge back to trunk with maturity, this approach should work great to simplify the release things. Could we resolve this soon, proceed and speed up with the 3.0 release? Thanks all. Regards, Kai -----Original Message----- From: Colin McCabe [mailto:cmcc...@apache.org] Sent: Wednesday, June 08, 2016 3:33 AM To: common-dev@hadoop.apache.org Subject: Re: Why there are so many revert operations on trunk? One anti-pattern that keeps coming up over and over again is people trying to do big and complex features without feature branches. This happened with HDFS truncate as well. This inevitably leads to controversy because people see very big and invasive patches zooming past and get alarmed. Devops people see complicated new code going directly into production branches and freak out. Developers see new APIs getting added without much discussion and start pushing back. This all gets worse when it's combined with the lack of an up-to-date design doc. This leads to people asking the same questions over and over, since there's no central place they can go to do background reading about the new feature. It also tends to lead to arguments, since the design decisions that were made seem to come out of nowhere, rather than being justified by careful consideration of alternatives. When patches get committed directly to production branches, the discussion also gets mixed up with release management discussions, which are often contentious as well. Release management discussions can go on for a while at the best of times-- when you combine this with all the above, it just becomes really messy. My advice is, if 3 or more people ask you for a feature branch, just create a feature branch already! It makes things a lot simpler and less controversial. It decouples the feature development discussion from the release management discussion. It gives developers the ability to look at the feature as a whole, rather than feeling like they have to understand each commit in isolation. Devops people feel like they can relax because the decision about what stable branches to backport to will be made after they have a chance to clearly understand the new feature, rather than before. The branch merge email functions as a kind of overview of the feature which makes people more comfortable with it. Feature branches actually speed up development for medium or large-sized features. You can have branch committers who are not full committers, but can commit to the branch. You can rewrite your API at any time without worrying about compatibility. You can rewrite the history of the branch however you like to explore new approaches. You don't need to backport each of your patches to N stable branches. Some people seem scared by the need for a merge vote to merge a feature branch. But if your feature is big, you are going to get scrutiny anyway. Committing stuff directly to trunk or branch-2 is a not a "get out of jail free" card that bypasses community review. If anything, community review will probably be longer and more contentious because of the reasons above. People get frustrated when commits to production branches continue even while big questions about the feature still remain unanswered. We already have rules constraining the use of the -1 vote. Like any other discussion, -1 votes need to be "constructive"-- that is, they need to clearly spell out the way forward, rather than just saying no. In this particular case, the concerns we had were about the way the feature was being developed, and the API. I think that the discussion that is going on for HDFS async right now is healthy, and will lead to a better feature. We have people from downstream projects such as HBase commenting on the kind of APIs they would find useful. We have discussions about the impact on the RPC system, and the branches that it makes sense to target. And now that we have a feature branch, we have a lot more freedom to experiment. best, Colin On Tue, Jun 7, 2016, at 11:02, larry mccay wrote: > -1 needs not be a taken as a derogatory statement being a number > should actually make it less emotional. > It is dangerous to a community to become oversensitive to it. > > I generally see language such as "I am -1 on this until this > particular thing is fixed" or that it violates some common pattern or > precedence set in the project. This is perfectly reasonable language > and there is no reason to make the reviewer provide an alternative. > > So, I am giving my -1 to any proposal for rule changes on -1 votes. :) > > > On Tue, Jun 7, 2016 at 1:15 PM, Ravi Prakash <ravihad...@gmail.com> > wrote: > > > +1 on being more respectful. We seem to be having a lot of > > +distasteful > > discussions recently. If we fight each other, we are only helping > > our competitors win (and trust me, its out there). > > > > I would also respectfully request people not to throw -1s around. I > > have faced this a few times and its really frustrating. Every one > > has opinions and some times different people can't fathom why > > someone else thinks the way they do. I am pretty sure none of us is > > acting with malicious intent, so perhaps a little more tolerance, > > faith and trust will help all of us improve Hadoop and the ecosystem > > much faster. That's not to say that sometimes -1s are not warranted, > > but we should look to it as an extreme measure. Unfortunately there > > is very little disincentive right now to vote > > -1 . Maybe we should modify the rules..... if you vote -1 , you have > > to come up with an alternative implementation? (perhaps limit the > > amount of time you have to the amount already spent in producing the > > patch that you are against)? > > > > Just my 2 cents > > Ravi > > > > > > On Tue, Jun 7, 2016 at 7:54 AM, Junping Du <j...@hortonworks.com> wrote: > > > > > - We need to at the least force a reset of expectations w.r.t how > > > trunk and small / medium / incompatible changes there are treated. > > > We should > > hold > > > off making a release off trunk before this gets fully discussed in > > > the community and we all reach a consensus. > > > > > > +1. We should hold off any release work off trunk before we reach > > > +a > > > consensus. Or more and more developing work/features could be > > > affected > > just > > > like Larry mentioned. > > > > > > > > > - Reverts (or revert and move to a feature-branch) shouldn’t have > > > been unequivocally done without dropping a note / informing > > > everyone / > > building > > > consensus. > > > > > > Agree. To revert commits from other committers, I think we need > > > to: 1) provide technical evidence/reason that is solid as rack, > > > like: break functionality, tests, API compatibility, or > > > significantly offend code convention, etc. 2) Making consensus > > > with related contributors/committers based on these technical > > > reasons/evidences. Unfortunately, I didn't see > > we > > > ever do either thing in this case. > > > > > > > > > - Freaking out on -1’s and reverts - we as a community need to be > > > less stigmatic about -1s / reverts. > > > > > > +1. As a community, I believe we all prefer to work in a more > > > +friendly > > > environment. In many cases, -1 without solid reason will frustrate > > > people who are doing contributions. I think we should restraint > > > our -1 unless it is really necessary. > > > > > > > > > > > > Thanks, > > > > > > > > > Junping > > > > > > > > > ________________________________ > > > From: Vinod Kumar Vavilapalli <vino...@apache.org> > > > Sent: Monday, June 06, 2016 9:36 PM > > > To: Andrew Wang > > > Cc: Junping Du; Aaron T. Myers; common-dev@hadoop.apache.org; > > > hdfs-...@hadoop.apache.org; mapreduce-...@hadoop.apache.org; > > > yarn-...@hadoop.apache.org > > > Subject: Re: Why there are so many revert operations on trunk? > > > > > > Folks, > > > > > > It is truly disappointing how we are escalating situations that > > > can be resolved through basic communication. > > > > > > Things that shouldn’t have happened > > > - After a few objections were raised, commits should have simply > > > stopped before restarting again but only after consensus > > > - Reverts (or revert and move to a feature-branch) shouldn’t have > > > been unequivocally done without dropping a note / informing > > > everyone / > > building > > > consensus. And no, not even a release-manager gets this free pass. > > > Not on branch-2, not on trunk, not anywhere. > > > - Freaking out on -1’s and reverts - we as a community need to be > > > less stigmatic about -1s / reverts. > > > > > > Trunk releases: > > > This is the other important bit about huge difference of > > > expectations between the two sides w.r.t trunk and branching. Till > > > now, we’ve never > > made > > > releases out of trunk. So in-progress features that people deemed > > > to not need a feature branch could go into trunk without much > > > trouble. Given > > that > > > we are now making releases off trunk, I can see (a) the RM saying > > > "no, don’t put in-progress stuff and (b) the contributors saying > > > “no we don’t want the overhead of a branch”. I’ve raised related > > > topics (but only focusing on incompatible changes) before - > > > http://markmail.org/message/m6x73t6srlchywsn - but we never > > > decided anything. > > > > > > We need to at the least force a reset of expectations w.r.t how > > > trunk and small / medium / incompatible changes there are treated. > > > We should hold > > off > > > making a release off trunk before this gets fully discussed in the > > > community and we all reach a consensus. > > > > > > * Without a user API, there's no way for people to use it, so not > > > much advantage to having it in a release > > > > > > Since the code is separate and probably won't break any existing > > > code, I won't -1 if you want to include this in a release without > > > a user API, but again, I question the utility of including code that > > > can't be used. > > > > > > Clearly, there are two sides to this argument. One side claims the > > absence > > > of user-facing public / stable APIs, and that for all purposes > > > this is dead-code for everyone other than the few early adopters > > > who want to experiment with it. The other argument is to not put > > > this code before a user API. Again, I’d discuss with fellow > > > community members before making what the other side perceives as > > > unacceptable moves. > > > > > > From 2.8.0 perspective, it shouldn’t have landed there in the > > > first place > > > - I have been pushing for a release for a while with help only > > > from a few members of the community. But if you say that it has no > > > material impact > > on > > > the user story, having a by-default switched-off feature that > > > *doesn’t* destabilize the core release, I’d be willing to let it pass. > > > > > > +Vinod > > > > > --------------------------------------------------------------------- To unsubscribe, e-mail: common-dev-unsubscr...@hadoop.apache.org For additional commands, e-mail: common-dev-h...@hadoop.apache.org
