FrankChen021 opened a new issue, #20602: URL: https://github.com/apache/druid/issues/20602
_This issue was generated automatically by Claude Code (Anthropic's AI coding agent) running a scheduled CI-triage routine on behalf of @FrankChen021. Analysis and suggested fixes are AI-produced; please verify before acting on them._ **Status:** Open: no fix PR **Subject:** `StreamAppenderatorTest.testSimpleIngestion` (server, `unit tests / unit tests(main) (25, S*)`) **Failures:** 1 · **First seen:** 2026-10-14 · **Last seen:** 2026-10-14 ### Root cause Line 195 asserts `segmentGenerationMetrics.mergeTimeMillis() > 0`. `StreamAppenderator.mergeAndPush` measures merge time with a millisecond `Stopwatch` and `SegmentGenerationMetrics.setMergeTime` overwrites (not adds) the value, so the last merge of a one-row segment can finish in under 1 ms and record 0. Once the JVM is warm the reruns are just as fast, which is why all 4 surefire attempts failed. The commit (#20450) only changes expression selector reuse, and the same job passed on the neighbouring master commits. ### Suggested fix Relax the assertion to `mergeTimeMillis() >= 0` and keep `mergeCpuTime() > 0` (nanosecond resolution) as the real signal that a merge was timed; `persistTimeMillis() > 0` on line 192 has the same weakness. ### Occurrences Failed push-triggered master jobs only. The daily triage routine adds one row per new failed job. | Date | Commit | Job | Failure log | Detail | Reported in | |---|---|---|---|---|---| | 2026-10-14 | 3b44cc3857 (#20450) | `unit tests / unit tests(main) (25, S*) / test-jdk25-[S*]` | [job 115708013912](https://github.com/apache/druid/actions/runs/38520231469/job/115708013912) | `expected: <true> but was: <false>` at line 195 (`mergeTimeMillis() > 0`); 4/4 attempts failed | | -- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
