NormalizeLoop: fix normalize race#4168
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🔄 Flaky Test DetectedAnalysis: e2e TestGenericBQ failed with "UNEXPECTED TIMEOUT" waiting for inherited table rows to appear in BigQuery, a timing-dependent polling assertion in a slow external-service e2e test. ✅ Automatically retrying the workflow |
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🔄 Flaky Test DetectedAnalysis: TestApiPg/TestResyncFailed failed during teardown due to a race condition where the replication slot was still held by an active PID when the test tried to drop it — a timing issue unrelated to the test logic itself. ✅ Automatically retrying the workflow |
serprex
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Apr 13, 2026
Amogh-Bharadwaj
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LGTM |
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There's a race condition in normalizeLoop with the LastChan signaling mechanism.
The race:
normalizeLoopis insidestartNormalizeprocessing batch 346normRequests.Update(347)— this stores value 347, creates a new channel, and closes the old channelstartNormalizefor 346 returns, normalizeLoop goes back to the topnormalizeRequests.Wait()returns the new (unclosed) channel created in step 2normalizeLoopblocks on<-ch— but this channel will only be closed by the nextUpdate()(batch 348)Check for pending work via Load() before calling Wait(). Only block on the channel if there's genuinely nothing to process.