Releases branches 1.0 vs 1.1


#1

I’m trying to figure out the pattern for which changes make it into which release branch.

For example, I’m interested in the following two:
https://github.com/istio/istio/pull/10379 (release-1.0)
https://github.com/istio/istio/pull/9957 (release-1.1)

A few questions:

  1. Why are some changes pushed to 1.0 and others to 1.1 when they often seem similar in scope and severity?
  2. In the case of the change in the 1.0 branch above, when would that get merged into the 1.1 release snapshots? There was one released after the change but it wasn’t part of that for some reason.

Without knowing much about the release cycle here, it just seems like there’s a lot building up in 1.0 that may be difficult to get merged into 1.1.


#2

Nothing goes directly from the release-1.0 branch to the release-1.1 branch (so there will be no difficulty merging 1.0 branch code into 1.1 branch because that will never happen). If a fix is going into 1.1 and that fix needs to be backported to 1.0, then you need to create a separate PR built on top of release-1.0 (thus you will have two PRs - one for 1.1 and one for the backport into 1.0 branch).

The release-1.0 branch is solely for fixes going into the 1.0.x release stream. Istio 1.0.5 was the last release, but there may be a 1.0.6 release (I do not know the plans for 1.0.x) so that is why you see release-1.0 branch getting code committed to it.

Master branch is periodically getting updated with release-1.1 branch (i.e. release-1.1 is periodically getting merged into master)


#3

Thanks @jmazzitelli, that helps. I guess I’m still just wondering why things like PR #10379 were just merged into 1.0, then – I imagine there’s a reason it wasn’t needed against 1.1 or something.


#4

Jay, I think you did the right thing in the case of this PR - asking why the PR was not in the 1.1 branch (witihin the PR itself). Asking on discuss is likely not to yield good results. I don’t know the exact answer, but have pinged Costin to take a look.

Cheers
-steve


#5

Thanks, I appreciate it. This thread was to get more of a general understanding – not specific to those PRs and I feel @jmazzitelli covered that pretty well. The specific one was more of a follow-up since the PR discussion wasn’t getting good results either… figured it was worth a shot. :slight_smile:


#6

Normal process is to fix in master, test ( including perf) and backport.

For urgent customer prod issues - we do fix directly in rel branch, and port to master and other rel branches.

I’ve been a bit swamped - probably missed few, and unfortunately the 1.0 is too far off so auto merge doesn’t work. Also the code in ads changed and most fixes happened with separate PRs.