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https://issues.apache.org/jira/browse/FLINK-10333?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Flink Jira Bot updated FLINK-10333:
-----------------------------------
      Labels: auto-deprioritized-major  (was: stale-major)
    Priority: Minor  (was: Major)

This issue was labeled "stale-major" 7 ago and has not received any updates so 
it is being deprioritized. If this ticket is actually Major, please raise the 
priority and ask a committer to assign you the issue or revive the public 
discussion.


> Rethink ZooKeeper based stores (SubmittedJobGraph, MesosWorker, 
> CompletedCheckpoints)
> -------------------------------------------------------------------------------------
>
>                 Key: FLINK-10333
>                 URL: https://issues.apache.org/jira/browse/FLINK-10333
>             Project: Flink
>          Issue Type: Bug
>          Components: Runtime / Coordination
>    Affects Versions: 1.5.3, 1.6.0, 1.7.0, 1.11.3, 1.12.0
>            Reporter: Till Rohrmann
>            Priority: Minor
>              Labels: auto-deprioritized-major
>         Attachments: screenshot-1.png
>
>
> While going over the ZooKeeper based stores 
> ({{ZooKeeperSubmittedJobGraphStore}}, {{ZooKeeperMesosWorkerStore}}, 
> {{ZooKeeperCompletedCheckpointStore}}) and the underlying 
> {{ZooKeeperStateHandleStore}} I noticed several inconsistencies which were 
> introduced with past incremental changes.
> * Depending whether {{ZooKeeperStateHandleStore#getAllSortedByNameAndLock}} 
> or {{ZooKeeperStateHandleStore#getAllAndLock}} is called, deserialization 
> problems will either lead to removing the Znode or not
> * {{ZooKeeperStateHandleStore}} leaves inconsistent state in case of 
> exceptions (e.g. {{#getAllAndLock}} won't release the acquired locks in case 
> of a failure)
> * {{ZooKeeperStateHandleStore}} has too many responsibilities. It would be 
> better to move {{RetrievableStateStorageHelper}} out of it for a better 
> separation of concerns
> * {{ZooKeeperSubmittedJobGraphStore}} overwrites a stored {{JobGraph}} even 
> if it is locked. This should not happen since it could leave another system 
> in an inconsistent state (imagine a changed {{JobGraph}} which restores from 
> an old checkpoint)
> * Redundant but also somewhat inconsistent put logic in the different stores
> * Shadowing of ZooKeeper specific exceptions in {{ZooKeeperStateHandleStore}} 
> which were expected to be caught in {{ZooKeeperSubmittedJobGraphStore}}
> * Getting rid of the {{SubmittedJobGraphListener}} would be helpful
> These problems made me think how reliable these components actually work. 
> Since these components are very important, I propose to refactor them.



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