[jira] [Commented] (FLINK-5932) Order of legacy vs new state initialization in the AbstractStreamOperator.

["Aljoscha Krettek (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/FLINK-5932?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15887699#comment-15887699 ] 

Aljoscha Krettek commented on FLINK-5932:
-----------------------------------------

+1 I think this makes a lot of sense

[~srichter] what do you think?

> Order of legacy vs new state initialization in the AbstractStreamOperator.
> --------------------------------------------------------------------------
>
>                 Key: FLINK-5932
>                 URL: https://issues.apache.org/jira/browse/FLINK-5932
>             Project: Flink
>          Issue Type: Bug
>          Components: DataStream API
>    Affects Versions: 1.2.0
>            Reporter: Kostas Kloudas
>             Fix For: 1.3.0
>
>
> Currently in the {{AbstractStreamOperator::initializeState(OperatorStateHandles stateHandles)}}, the {{restoreStreamCheckpointed}} which is responsible for restoring state from previous Flink versions, (backwards compatibility) is called before the {{initializeState(StateInitializationContext context)}} which is responsible for initializing the state in Flink 1.2.
> This has the negative side effect that when implementing the backwards compatibility strategy for a given operator, we have to restore the old state, store it in local variables, and register it with the new state abstractions in the {{initializeState()}} or the {{open()}}. This creates a lot of unnecessary code in the operators, and potential memory leaks if the local variables are not "null-ified".
> This issue proposes to call the {{restoreStreamCheckpointed}} after the {{initializeState(StateInitializationContext context)}}. This way, the new operator state will have been initialized (e.g. keyed state), and the {{restoreStreamCheckpointed}} will be able to register its state directly with the new abstractions, instead of putting it in local variables and wait for the {{initializeState}} or the {{open()}} to re-register it.



--
This message was sent by Atlassian JIRA
(v6.3.15#6346)