Hi Steve, let me confirm that I understand your proposal correctly: - Release an intermediate Hadoop 3 a few months out, based on JDK7 and with bumped library versions - Release a Hadoop 4 mid next year, based on JDK8
I question the utility of an intermediate Hadoop 3 like this. Assuming that it gets out in September (i.e. roughly when a 2.6 would land), we're looking at a valid lifespan of about 7 months before JDK7 is EOL in April. If this release also breaks compatibility by changing library versions, then it looks less and less appealing from a user perspective. I suspect it would end up seeing low adoption as everyone waits (at most) 7 months for the JDK8-based release to emerge. I'd be more okay with an intermediate release with no incompatible changes whatsoever besides bumping the JDK requirement to JDK7. However, it'd still be a weak release considering that branch-2 already runs fine on JDK7, and it looks somewhat bad publicly as we burn another major release number less than a year since 2.x going GA. This is why I'd like to keep my original proposal on the table: keep going with branch-2 in the near term, while working towards a JDK8-based Hadoop 3 by April next year. It doesn't need to be a big bang release either. I'd be delighted if we could rolling upgrade from one to the other. I just didn't want to rule out the inclusion of some very compelling feature outright. Trust me though, I'd be the first person to ask about compatibility if such a feature does come up. I'll also posit that people will shy away from using JDK8 features while branch-2 remains in active use. There's definitely some new shiny there, but nothing compelling enough to me personally when weighed against the pain of harder branch-2 backports. Let's try to keep this thread focused on the planning side of things though, deferring JDK-feature-related discussion to a different thread. We'd need to draw up a code-style doc on the wiki, but it sounds like something Steve and/or I could draft initially. Thanks, Andrew On Fri, Jun 20, 2014 at 10:02 PM, Arun C Murthy <a...@hortonworks.com> wrote: > > On Jun 20, 2014, at 9:51 PM, Steve Loughran <ste...@hortonworks.com> > wrote: > > > On 20 June 2014 21:35, Steve Loughran <ste...@hortonworks.com> wrote: > > > >> > >> This actually argues in favour of > >> > >> -renaming branch-2 branch-3 after a release > >> -making trunk hadoop-4 > >> > >> -getting hadoop 3 released off the new branch-3 out in 2014, effectively > >> being an iteration of branch-2 with updated java , moves of (off?) > guava, > >> off jetty, lib changes, but no other significant "big bang" features > >> > >> > >> Hadoop 4.x then becomes the 2015 release, which can add more stuff. In > >> particular, anything that goes into Hadoop 4 for which there's no > intent to > >> support in hadoop 2 & 3, can use the java 8 language features sooner > rather > >> than later. > >> > >> > >> > > I should add that I'm willing to be the person who gets the Java-7 based > > Hadoop 3.x out the door later this year > > +1 that makes sense to me. Thanks for volunteering Steve - I'm glad to > share the pain… ;-) > > Arun > -- > CONFIDENTIALITY NOTICE > NOTICE: This message is intended for the use of the individual or entity to > which it is addressed and may contain information that is confidential, > privileged and exempt from disclosure under applicable law. If the reader > of this message is not the intended recipient, you are hereby notified that > any printing, copying, dissemination, distribution, disclosure or > forwarding of this communication is strictly prohibited. If you have > received this communication in error, please contact the sender immediately > and delete it from your system. Thank You. >
