Fix racing conditions in Postgres streamer #1002
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Signed-off-by: Robert Vollmer <[email protected]>
While it might technically work, it hands control back to the Postgres module very early and then relies on microtask scheduling to ensure the correct order. But after parsing the message, the function already uses a mutex for correct ordering of chunks within a stream, so each chunk is queued twice. Parsing synchronously avoids that back-and-forth and makes the code flow easier to follow. Signed-off-by: Robert Vollmer <[email protected]>
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Signed-off-by: Robert Vollmer <[email protected]>
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I'm currently building a chat using
DurableAgentand frequently (almost for every message) had missing chunks. Often thetext-startwas missing or some of the words were lost. The chunks are persisted totally fine.Investigations have shown that the chunks were dismissed as out-of-order. Indeed, they arrived at the
listenhandler in a different order than they were processed inwriteToStreamMulti(). Since making the proposed changes - especiallyawaiting the `postgres.notify()´ calls - I haven't seen a single missing chunk.