I think the 'only backport bug fixes to branches' principle remains sound. But what's a bug fix? Something that changes behavior to match what is explicitly supposed to happen, or implicitly supposed to happen -- implied by what other similar things do, by reasonable user expectations, or simply how it worked previously.
Is this a bug fix? I guess the criteria that matches is that behavior doesn't match reasonable user expectations? I don't know enough to have a strong opinion. I also don't think there is currently an objection to backporting it, whatever it's called. Is the question whether this needs a new release? There's no harm in another point release, other than needing a volunteer release manager. One could say, wait a bit longer to see what more info comes in about 2.4.1. But given that 2.4.1 took like 2 months, it's reasonable to move towards a release cycle again. I don't see objection to that either (?) The meta question remains: is a 'bug fix' definition even agreed, and being consistently applied? There aren't correct answers, only best guesses from each person's own experience, judgment and priorities. These can differ even when applied in good faith. Sometimes the variance of opinion comes because people have different info that needs to be surfaced. Here, maybe it's best to share what about that offline conversation was convincing, for example. I'd say it's also important to separate what one would prefer from what one can't live with(out). Assuming one trusts the intent and experience of the handful of others with an opinion, I'd defer to someone who wants X and will own it, even if I'm moderately against it. Otherwise we'd get little done. In that light, it seems like both of the PRs at issue here are not _wrong_ to backport. This is a good pair that highlights why, when there isn't a clear reason to do / not do something (e.g. obvious errors, breaking public APIs) we give benefit-of-the-doubt in order to get it later. On Wed, Apr 17, 2019 at 12:09 PM Ryan Blue <rb...@netflix.com.invalid> wrote: > Sorry, I should be more clear about what I'm trying to say here. > > In the past, Xiao has taken the opposite stance. A good example is PR > #21060 <https://github.com/apache/spark/pull/21060#issuecomment-381671683> > that was a very similar situation: behavior didn't match what was expected > and there was low risk. There was a long argument and the patch didn't make > it into 2.3 (to my knowledge). > > What we call these low-risk behavior fixes doesn't matter. I called it a > bug on #21060 but I'm applying Xiao's previous definition here to make a > point. Whatever term we use, we clearly have times when we want to allow a > patch because it is low risk and helps someone. Let's just be clear that > that's perfectly fine. > > On Wed, Apr 17, 2019 at 9:34 AM Ryan Blue <rb...@netflix.com> wrote: > >> How is this a bug fix? >> >> On Wed, Apr 17, 2019 at 9:30 AM Xiao Li <lix...@databricks.com> wrote: >> >>> Michael and I had an offline discussion about this PR >>> https://github.com/apache/spark/pull/24365. He convinced me that this >>> is a bug fix. The code changes of this bug fix are very tiny and the risk >>> is very low. To avoid any behavior change in the patch releases, this PR >>> also added a legacy flag whose default value is off. >>> >>>
