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https://issues.apache.org/jira/browse/KAFKA-21034?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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이선민 reassigned KAFKA-21034:
---------------------------

    Assignee: 이선민

> Wipe global store on start up, when corrupted
> ---------------------------------------------
>
>                 Key: KAFKA-21034
>                 URL: https://issues.apache.org/jira/browse/KAFKA-21034
>             Project: Kafka
>          Issue Type: Improvement
>          Components: streams
>            Reporter: Uladzislau Blok
>            Assignee: 이선민
>            Priority: Minor
>
> *Problem statement:*
> Currently, Kafka Streams provides an automated recovery mechanism for 
> standard state stores: when a {{StreamThread}} starts up, it can wipe a 
> corrupted local store and rebuild it from its changelog.
> However, this self-healing behavior is not supported for global state stores. 
> Implementing dynamic runtime recovery for global stores would require complex 
> thread synchronization—namely, pausing all stream threads until the global 
> store has completely rebuilt. Streams simply lets the application fail fast 
> and crash
> Because Streams does not wipe a corrupted global store before crashing, the 
> corrupted data remains on disk. On subsequent restarts, the application 
> encounters the same corrupted state and crashes again. In environments with 
> automated restart policies (such as Kubernetes StatefulSets), this leads to 
> an unrecoverable {{{}CrashLoopBackOff{}}}, requiring manual intervention to 
> exec into the pod and delete the local directory.
> Instead of attempting complex runtime thread synchronization, we can handle 
> this purely at the startup/initialization phase:
>  # Catch the store corruption exception when the global state store 
> initializes.
>  # Automatically wipe the corrupted global store directory on disk.
>  # Terminate or fail the current startup sequence cleanly.
> On the next restart the application will start with an empty store directory 
> and restore the global store from scratch, breaking the crash loop without 
> manual intervention.
>  
> *Mechanics:* 
> We already have similar mechanism:
> {{GlobalStreamThread#initialize}} -> {{stateConsumer#initialize}} -> throws 
> InvalidOffsetException -> {{{}closeStateConsumer(stateConsumer, true){}}}, 
> where true means wipe state store
> In other cases:
> StreamsException -> {{closeStateConsumer(stateConsumer, false)}}
> Throwable -> {{closeStateConsumer(stateConsumer, false)}}
>  
> *Potential solution:*
> Catch exceptions of other types (exact list to be analyzed). I saw it for 
> TaskCorruptedException(ProcessorStateException) ({{{}RocksDBStore#openDB ; 
> AbstractColumnFamilyAccessor#open{}}})
>  
> *Open questions:*
>  * Do we need KIP for this change?
>  * Exact exception (or list of exceptions to trigger wiping)



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