fix: isolate advisory lock from other flush operations to prevent deadlocks#19684
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miketheman wants to merge 1 commit intopypi:mainfrom
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fix: isolate advisory lock from other flush operations to prevent deadlocks#19684miketheman wants to merge 1 commit intopypi:mainfrom
miketheman wants to merge 1 commit intopypi:mainfrom
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…dlocks ensure_monotonic_journals acquired a global advisory lock in before_flush, then the same flush executed all pending INSERTs/UPDATEs. When a File INSERT's unique constraint check waited on a concurrent transaction that was itself waiting for the advisory lock, a deadlock cycle formed. Refactor the listener to automatically defer JournalEntries when other objects are also pending. The before_flush handler expunges them, and an after_flush handler restores them for a subsequent flush cycle where they're the only pending objects. This ensures the advisory lock is never held while unrelated operations execute. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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ensure_monotonic_journalsacquired a global advisory lock inbefore_flush, then the same flush executed all pending INSERTs/UPDATEs.When a
FileINSERT's unique constraint check waited on a concurrent transaction that was itself waiting for the advisory lock, a deadlock cycle formed.Refactor the listener to automatically defer
JournalEntrieswhen other objects are also pending. Thebefore_flushhandler expunges them, and anafter_flushhandler restores them for a subsequent flush cycle where they're the only pending objects.This ensures the advisory lock is never held while unrelated operations execute.