[UPDATE] Release 1.13 feature freeze

[Dawid Wysakowicz <dw...@apache.org>]

Hi all,

The agreed date of a feature freeze is due in about a month. Therefore
we thought it would be a good time to give an update of the current
progress.

From the information we gathered there are currently no known obstacles
or foreseeable delays. We are still aiming for the end of March as the
date for a feature freeze.

Some update on the progress of particular issues. Most of the issues
listed in the https://cwiki.apache.org/confluence/x/jAhRCg are well on
track. We will list only the issues that we feel might not end up in the
release or end up there partially:

  * Tolerate temporarily suspended ZooKeeper connections (FLINK-10052)
  * Support shipping local/remote files for yarn/k8s
    integrations(FLINK-20681 / FLINK-20811 / FLINK-20867)
  * Consistent Flink SQL time function behavior (FLIP-162)

These are long lasting efforts and are planned to be delivered based on
best effort, therefore they might not be fully functional in 1.13:

  * Generalized incremental checkpoints
  * Incremental snapshots for heap-based state backend

We have 4 release blockers as of today:

Checkpointing:

  * https://issues.apache.org/jira/browse/FLINK-21453
    BoundedOneInput.endInput is NOT called when doing stop with
    savepoint WITH drain

Dependencies:

  * https://issues.apache.org/jira/browse/FLINK-21152 Bump flink-shaded
    to 13.0

Coordination:

  * https://issues.apache.org/jira/browse/FLINK-21030 Broken job restart
    for job with disjoint graph

Connectors:

  * https://issues.apache.org/jira/browse/FLINK-20188 Add Documentation
    for new File Source

We have 100 test instabilities across all versions out of which 37
occurred on master (1.13) branch.

Let me know if we made a mistake somewhere or something is inaccurate.
Moreover everyone is welcome to give more thorough update if you feel
like so.

Your release managers

Guowei & Dawid