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https://issues.apache.org/jira/browse/CASSANDRA-16619?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17450642#comment-17450642
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Jeremiah Jordan commented on CASSANDRA-16619:
---------------------------------------------

I would expect someone to see more data replayed, because the intervals would 
not be ignored, but the end result data wise should be the same. The data in 
the commitlogs should be idempotent so it is safe to replay even if it is 
already in a given sstable.

> Loss of commit log data possible after sstable ingest
> -----------------------------------------------------
>
>                 Key: CASSANDRA-16619
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-16619
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Local/Commit Log
>            Reporter: Jacek Lewandowski
>            Assignee: Jacek Lewandowski
>            Priority: Normal
>             Fix For: 3.0.25, 3.11.11, 4.0-rc2, 4.0
>
>          Time Spent: 2h
>  Remaining Estimate: 0h
>
> SSTable metadata contains commit log positions of the sstable. These 
> positions are used to filter out mutations from the commit log on restart and 
> only make sense for the node on which the data was flushed.
> If an SSTable is moved between nodes they may cover regions that the 
> receiving node has not yet flushed, and result in valid data being lost 
> should these sections of the commit log need to be replayed.
> Solution:
> The chosen solution introduces a new sstable metadata (StatsMetadata) - 
> originatingHostId (UUID), which is the local host id of the node on which the 
> sstable was created, or null if not known. Commit log intervals from an 
> sstable are taken into account during Commit Log replay only when the 
> originatingHostId of the sstable matches the local node's hostId.
> For new sstables the originatingHostId is set according to StorageService's 
> local hostId.
> For compacted sstables the originatingHostId set according to 
> StorageService's local hostId, and only commit log intervals from local 
> sstables is preserved in the resulting sstable.
> discovered by [~jakubzytka]



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