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https://issues.apache.org/jira/browse/FLINK-26079?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17492404#comment-17492404
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Yuan Mei commented on FLINK-26079:
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>> shouldn't claim mode with changelog state backend wrap it first and then be
>> added to the checkpoint store?
> As per the discussion above, this doesn't seem a good option because JM
> should NOT be aware of how specific backends build their state handles.
That is a fair statement, but from an implementation point of view, let me
state this in a different way:
>> Conceptually, when claiming: shouldn't we claim as a changelog checkpoint if
>> we are using changelog state-backend after restoring?
> What do you mean by "claim as a changelog checkpoint"?
What I mean is: when we restore a job from a normal checkpoint (created by
non-changelog state backend) and use changelog state backend with CLAIM mode,
It's natural that we make/transfer the checkpoint to the first changelog-style
checkpoint.
> I personally meant that after the feature freeze we'll probably fix the root
> cause.
I do not disagree with that
> [Changelog] Disallow recovery from non-changelog checkpoints
> ------------------------------------------------------------
>
> Key: FLINK-26079
> URL: https://issues.apache.org/jira/browse/FLINK-26079
> Project: Flink
> Issue Type: Bug
> Components: Runtime / Configuration, Runtime / State Backends
> Reporter: Roman Khachatryan
> Assignee: Roman Khachatryan
> Priority: Blocker
> Labels: pull-request-available
> Fix For: 1.15.0
>
>
> Extracted from FLINK-25872.
> The issue is with the CLAIM mode:
> > Because discarding an initial checkpoint will invalidate its "private"
> > state which might be in use by future checkpoints.
> > Normally, changelog backend wraps it and registers with tjhe
> > SharedStateRegistry.
> > But when recovering from non-changelog checkpoint, it is first added to the
> > Checkpoint store, and wrapping in subsequent checkpoints doesn't help.
> NO_CLAIM mode is not supported.
> LEGACY could work.
> But it's difficult to differentiate between the modes on TM, where backend
> type is reliably known (see the discussion below).
> CANONICAL non-changelog savepoints must still be supported.
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