Hi folks! Consider this the start of my release manager duties for HBase 3.0.0.
HBase 2.0 started alpha releases in Jun 2017 and went GA in April 2018. I'd like to start alpha releases for HBase 3.0 next week and aim for a GA in December or January. As RM, I consider the alpha releases a chance for folks to shake things out and for us to decide as a community what makes it in or not for the release line. Once things start being labeled beta, I would like things to be feature frozen. My current goal is to set beta in May or June. I would like HBase 3.0 to be the start of us getting into practice on tighter iteration cycles for major versions. 2.5 years is too long. We should try to look at our version numbers as akin to Linux kernel version numbers. Something useful to those interested in the internals of the project but not something where most downstream users have to dread major bumps. To that end I would like HBase 3.0 to be rolling upgradable from HBase 2.y at GA. Ultimately, I would like to update our reference guide's section on compatibility to state that future major releases will similarly be rolling upgradable from some minor release of the prior major release line. Given my desire to make major upgrades less of a world changing event for our downstream folks, I also don't have any new features that I feel strongly need to make it into HBase 3.0. I'll do a review of what's currently there so we can motivate folks, but I won't do that until we're ready to declare beta since that will be when I'll have a better idea of what's actually ready to ship. With the major version change I'd like us to shed some maintenance burden in the project. For each of these, doing that will require getting a branch-2 release out that can successfully opt-in to the HBase 3 requirement and run on the current HBase 2 requirement. That way folks can do a rolling restart within HBase 2 to make the change, then do a rolling upgrade to HBase 3. = Hadoop 3 only The Hadoop community's focus increasingly is on Hadoop 3.y releases. A substantial amount of our dependency handling is tied to trying to span both Hadoop 2 and Hadoop 3. I would like us to drop Hadoop 2 entirely. I think branch-2 is currently in a place where running on Hadoop 3 is reasonable. = JDK11+ We've been bending over backwards on jdk versions for a while. Maven build sets up for multiple jdk builds are a PITA and our existing build is already too complicated. I'd like us to get branch-2 into a solid state for running on either JDK8 or JDK11 so folks can do production upgrades on those releases. I'd like HBase 3 to be jdk11+ only so that we can reduce our test footprint in the project and start to entertain features that don't work with jdk8. For example, we can't start to figure out how we should fit in the module system as things are. = No more Log4j 1 We got through 95% of the work to make our logging system pluggable, but we still ship with log4j 1 as the out of the box solution. I want HBase 3 to ship with some other slf4j backend and I want that same backend to be a realistic option for branch-2 users to deploy in production. = Minimize Hadoop needs I would like to isolate the things we have that reach into Hadoop internals so that we can ease the logistics of changing the Hadoop version we run on and minimize the extra stuff we carry around for those who don't run on Hadoop at all. This will involve moving the stuff we have that reaches into internals into one or more module(s) and updating our artifacts so that we can tell where our hadoop related dependencies are in an installation.