The general forces are that new versions of things to support emerge, and are valuable to support, but have some cost to support in addition to old versions. And the old versions become less used and therefore less valuable to support, and at some point it tips to being more cost than value. It's hard to judge these costs and benefits.
Scala is perhaps the trickiest one because of the general mutual incompatibilities across minor versions. The cost of supporting multiple versions is high, and a third version is about to arrive. That's probably the most pressing question. It's actually biting with some regularity now, with compile errors on 2.10. (Python I confess I don't have an informed opinion about.) Java, Hadoop are not as urgent because they're more backwards-compatible. Anecdotally, I'd be surprised if anyone today would "upgrade" to Java 7 or an old Hadoop version. And I think that's really the question. Even if one decided to drop support for all this in 2.1.0, it would not mean people can't use Spark with these things. It merely means they can't necessarily use Spark 2.1.x. This is why we have maintenance branches for 1.6.x, 2.0.x. Tying Scala 2.11/12 support to Java 8 might make sense. In fact, I think that's part of the reason that an update in master, perhaps 2.1.x, could be overdue, because it actually is just the beginning of the end of the support burden. If you want to stop dealing with these in ~6 months they need to stop being supported in minor branches by right about now. On Tue, Oct 25, 2016 at 4:47 PM Mark Hamstra <m...@clearstorydata.com> wrote: > What's changed since the last time we discussed these issues, about 7 > months ago? Or, another way to formulate the question: What are the > threshold criteria that we should use to decide when to end Scala 2.10 > and/or Java 7 support? > > On Tue, Oct 25, 2016 at 8:36 AM, Sean Owen <so...@cloudera.com> wrote: > > I'd like to gauge where people stand on the issue of dropping support for > a few things that were considered for 2.0. > > First: Scala 2.10. We've seen a number of build breakages this week > because the PR builder only tests 2.11. No big deal at this stage, but, it > did cause me to wonder whether it's time to plan to drop 2.10 support, > especially with 2.12 coming soon. > > Next, Java 7. It's reasonably old and out of public updates at this stage. > It's not that painful to keep supporting, to be honest. It would simplify > some bits of code, some scripts, some testing. > > Hadoop versions: I think the the general argument is that most anyone > would be using, at the least, 2.6, and it would simplify some code that has > to reflect to use not-even-that-new APIs. It would remove some moderate > complexity in the build. > > > "When" is a tricky question. Although it's a little aggressive for minor > releases, I think these will all happen before 3.x regardless. 2.1.0 is not > out of the question, though coming soon. What about ... 2.2.0? > > > Although I tend to favor dropping support, I'm mostly asking for current > opinions. > > >
