pvillard31 opened a new pull request, #10864:
URL: https://github.com/apache/nifi/pull/10864

   # Summary
   
   NIFI-15519 - Skip flow save during shutdown to preserve processor 
auto-resume states
   
   OK, thanks to the reporter and the data shared with me, I was able to track 
down the issue. At a high level, during graceful shutdown, `SaveReportingTask` 
can execute after `FlowController.shutdown()` has already set all processors' 
desired state to `STOPPED`.
   
   If this happens, `VersionedDataflowMapper` maps the `STOPPED` state to 
`ENABLED` in `flow.json.gz`. On the next startup, `VersionedFlowSynchronizer` 
reads `ENABLED` (not `RUNNING`) and does not add the processors to 
`startConnectablesAfterInitialization`, so `onFlowInitialized()` starts zero 
components.
   
   This is a race condition: the `SaveReportingTask` runs on a scheduled 
executor every 500ms and also runs explicitly at the end of 
`StandardFlowService.stop()`. If a save request (`saveHolder`) is pending when 
shutdown begins, the save executes after processors are stopped, overwriting 
the previously saved `RUNNING` states with `ENABLED`.
   
   The issue might happen more frequently when using flow registry versioning 
which triggers frequent background `saveFlowChanges()` calls, making it highly 
likely that a save is pending at shutdown time.
   
   The system test easily reproduces the issue and the test would fail without 
the fix.
   
   # Tracking
   
   Please complete the following tracking steps prior to pull request creation.
   
   ### Issue Tracking
   
   - [ ] [Apache NiFi Jira](https://issues.apache.org/jira/browse/NIFI) issue 
created
   
   ### Pull Request Tracking
   
   - [ ] Pull Request title starts with Apache NiFi Jira issue number, such as 
`NIFI-00000`
   - [ ] Pull Request commit message starts with Apache NiFi Jira issue number, 
as such `NIFI-00000`
   - [ ] Pull request contains [commits 
signed](https://docs.github.com/en/authentication/managing-commit-signature-verification/signing-commits)
 with a registered key indicating `Verified` status
   
   ### Pull Request Formatting
   
   - [ ] Pull Request based on current revision of the `main` branch
   - [ ] Pull Request refers to a feature branch with one commit containing 
changes
   
   # Verification
   
   Please indicate the verification steps performed prior to pull request 
creation.
   
   ### Build
   
   - [ ] Build completed using `./mvnw clean install -P contrib-check`
     - [ ] JDK 21
     - [ ] JDK 25
   
   ### Licensing
   
   - [ ] New dependencies are compatible with the [Apache License 
2.0](https://apache.org/licenses/LICENSE-2.0) according to the [License 
Policy](https://www.apache.org/legal/resolved.html)
   - [ ] New dependencies are documented in applicable `LICENSE` and `NOTICE` 
files
   
   ### Documentation
   
   - [ ] Documentation formatting appears as expected in rendered files
   


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