[wernerdv]

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[github-actions]

Possible compatibility issues. Please, check rolling upgrade cases

This PR modifies protected classes (with Order annotation).
Changes to these classes can break rolling upgrade compatibility.

Affected files:

• modules/core/src/main/java/org/apache/ignite/internal/processors/cache/query/continuous/CacheContinuousQueryHandler.java

[Copilot]

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Copilot review overview

3 open issues

• The PR description currently contains only the contribution checklist template and does not… · New
• Closing cancelableTask via reflective access is brittle (field name coupling) and can make… · New
• This test intends to ensure a single backup-ack covers multiple topology versions, but after… · New

What changed in this PR

Fixes an issue where continuous query backup acknowledgements spanning multiple topology versions were not sent to all backup nodes.

Changes:

• Adjusted backup-ack send de-duplication to key by the actual destination node ID.
• Added a regression test that forces an acknowledgement to cover multiple topology versions (topology change mid-stream).

File	Description
modules/​core/​src/​main/​java/​org/​apache/​ignite/​internal/​processors/​cache/​query/​continuous/​CacheContinuousQueryHandler.java	Fixes per-node “already sent” tracking when sending backup acknowledgements across topology versions.
modules/​core/​src/​test/​java/​org/​apache/​ignite/​internal/​processors/​continuous/​ContinuousQueryBuffersCleanupTest.java	Adds a regression test reproducing the multi-topology-version backup-ack scenario and asserting CQ buffers are eventually cleared.

_{Review effort: Lite}