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https://issues.apache.org/jira/browse/IGNITE-17738?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Anton Vinogradov updated IGNITE-17738:
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    Attachment: PartialHistoricalRebalanceTest.java

> Cluster must be able to fix the inconsistency on restart by itself
> ------------------------------------------------------------------
>
>                 Key: IGNITE-17738
>                 URL: https://issues.apache.org/jira/browse/IGNITE-17738
>             Project: Ignite
>          Issue Type: Sub-task
>            Reporter: Anton Vinogradov
>            Priority: Major
>              Labels: iep-31, ise
>         Attachments: PartialHistoricalRebalanceTest.java
>
>
> On cluster restart (because of power-off, OOM or some other problem) it's 
> possible to have PDS inconsistent (primary partitions may contain operations 
> missed on backups as well as counters may contain gaps even on primary).
> 1) Currently, "historical rebalance" is able to sync the data to the highest 
> LWM for every partition. 
> Most likely, a primary will be chosen as a rebalance source, but the data 
> after the LWM will not be rebalanced. So, all updates between LWM and HWM 
> will not be synchronized.
> Such partition may be rebalanced correctly "later" in case of full rebalance 
> will be triggered sometime.
> 2) In case LWM is the same on primary and backup, rebalance will never happen 
> for such partition.
> A possible solution for the case when the cluster failed and restarted (same 
> baseline) is to fix the counters automatically (when cluster composition is 
> equal to the baseline specified before the crash).
> Counters should be set as
>  - HWM at primary and as LWM at backups for caches with 2+ backups,
>  - LWM at primary and as HWM at backups for caches with a single backup.



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