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https://issues.apache.org/jira/browse/CASSANDRA-16619?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17450486#comment-17450486
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Stefan Miklosovic commented on CASSANDRA-16619:
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Ok I am reading this:
[https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/db/commitlog/CommitLogReplayer.java#L290-L313]
After closer look it seems that it relates to SSTables, not commit logs. So
basically it will replay all "commitLogIntervals", whatever it means, I am not
familiar with this code, and it does not have anything in common with
restore_point_in_time setting or anything related to that replay path. It is
just because SSTables were created on the other node, host ids do not match, so
it will replay all commit log intervals and these commit log intervals are
maybe covering all intervals of commit logs I want to replay, right? Because,
clearly, there is less mutations, physically, in these sstables then in
sstables + commit logs so when I see all mutations being replayed, the stuff
this patch introduced will somehow replay it all ...
> 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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