ryanmeowy commented on issue #10203: URL: https://github.com/apache/seatunnel/issues/10203#issuecomment-6471925768
@SEZ9 that statement is already in the thread — it is the "On a death inside the backfill" paragraph of my 24 Oct reply ([here](https://github.com/apache/seatunnel/issues/10203#issuecomment-6379487210)): > The HIGH watermark is dispatched before the bounded backfill, but it is not checkpointed yet: `MySqlSnapshotSplitReadTask:154` writes it onto `SnapshotSplitChangeEventSourceContext` (the backfill's stop offset), and both state fields stay null until the emitter consumes the batch. On the exactly-once path `IncrementalSourceScanFetcher.pollSplitRecordsIfExactlyOnce:148-198` returns `[low ... high]` only after the END watermark, so a mid-backfill checkpoint persists the split with both watermarks null and restore re-runs it as 2a — because `isSnapshotReadFinished()` is false, not because the split is missing from a finished-splits map (`IncrementalSourceReader.addSplits:152-153` rebuilds it from the watermark pair). Once a checkpoint carries both watermarks, restore treats the split as 2b without replaying, whether or not `onSplitFinished` had run. So I did not duplicate it into the 2a/2b section of the 23 Oct table comment; if you would rather have it there as well, say so and I will add it. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
