fix compaction kept-tail mapping after prior summaries#2646
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rumpl wants to merge 1 commit intodocker:mainfrom
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fix compaction kept-tail mapping after prior summaries#2646rumpl wants to merge 1 commit intodocker:mainfrom
rumpl wants to merge 1 commit intodocker:mainfrom
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Assessment: 🟡 NEEDS ATTENTION
One likely bug was found in the changed code.
| Severity | Count |
|---|---|
| 🟡 Medium (LIKELY) | 1 |
Summary: The PR correctly fixes the core compaction index-mapping bug (raw session indexes instead of filtered message indexes). One issue was identified in the new function: the guard cannot distinguish between "FirstKeptEntry unset" and "FirstKeptEntry legitimately equals 0" (compaction kept everything from the start). The same pattern exists in the unchanged in .
Rebuild the compactor input with provenance back to raw session item indexes instead of mapping filtered GetMessages indexes directly onto sess.Messages. Previous compactions inject a synthetic session summary message, so repeated compaction could compute a FirstKeptEntry that pointed at already-summarized history and resurrect old messages. Honor the documented FirstKeptEntry sentinel by using -1 for no kept tail and treating 0 as a valid raw session index. Apply the same reconstruction rule in the session and compactor paths, update SQLite defaults, and preserve FirstKeptEntry when branching sessions. Signed-off-by: Djordje Lukic <djordje.lukic@docker.com>
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derekmisler
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May 5, 2026
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Rebuild the compactor input with provenance back to raw session item indexes instead of mapping filtered GetMessages indexes directly onto sess.Messages. Previous compactions inject a synthetic session summary message, so repeated compaction could compute a FirstKeptEntry that pointed at already-summarized history and resurrect old messages.
Expose a safe Session.SnapshotItems helper for the compactor and add a regression test covering compaction after a prior summary.