+1 Regards, Yi Liu
-----Original Message----- From: Andrew Wang [mailto:andrew.w...@cloudera.com] Sent: Tuesday, March 03, 2015 7:20 AM To: common-...@hadoop.apache.org; mapreduce-dev@hadoop.apache.org; hdfs-...@hadoop.apache.org; yarn-...@hadoop.apache.org Subject: Looking to a Hadoop 3 release Hi devs, It's been a year and a half since 2.x went GA, and I think we're about due for a 3.x release. Notably, there are two incompatible changes I'd like to call out, that will have a tremendous positive impact for our users. First, classpath isolation being done at HADOOP-11656, which has been a long-standing request from many downstreams and Hadoop users. Second, bumping the source and target JDK version to JDK8 (related to HADOOP-11090), which is important since JDK7 is EOL in April 2015 (two months from now). In the past, we've had issues with our dependencies discontinuing support for old JDKs, so this will future-proof us. Between the two, we'll also have quite an opportunity to clean up and upgrade our dependencies, another common user and developer request. I'd like to propose that we start rolling a series of monthly-ish series of 3.0 alpha releases ASAP, with myself volunteering to take on the RM and other cat herding responsibilities. There are already quite a few changes slated for 3.0 besides the above (for instance the shell script rewrite) so there's already value in a 3.0 alpha, and the more time we give downstreams to integrate, the better. This opens up discussion about inclusion of other changes, but I'm hoping to freeze incompatible changes after maybe two alphas, do a beta (with no further incompat changes allowed), and then finally a 3.x GA. For those keeping track, that means a 3.x GA in about four months. I would also like to stress though that this is not intended to be a big bang release. For instance, it would be great if we could maintain wire compatibility between 2.x and 3.x, so rolling upgrades work. Keeping branch-2 and branch-3 similar also makes backports easier, since we're likely maintaining 2.x for a while yet. Please let me know any comments / concerns related to the above. If people are friendly to the idea, I'd like to cut a branch-3 and start working on the first alpha. Best, Andrew
