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https://issues.apache.org/jira/browse/CASSANDRA-10979?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15109177#comment-15109177
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Jeff Ferland commented on CASSANDRA-10979:
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Applied the patch to a node that had just come up from streaming and was 700+ 
tables in L0. After restart, observed that as L0 was shifted into L1, L0 
continued to compact new tables to prevent the extreme growth of tables.

Thank you. Again still requesting a merge into 2.1 since streaming and repair 
with LCS are practically broken for us without this patch.

> LCS doesn't do L0 STC on new tables while an L0->L1 compaction is in progress
> -----------------------------------------------------------------------------
>
>                 Key: CASSANDRA-10979
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-10979
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Compaction
>         Environment: 2.1.11 / 4.8.3 DSE.
>            Reporter: Jeff Ferland
>            Assignee: Carl Yeksigian
>              Labels: compaction, leveled
>             Fix For: 3.x
>
>         Attachments: 10979-2.1.txt
>
>
> Reading code from 
> https://github.com/apache/cassandra/blob/cassandra-2.1/src/java/org/apache/cassandra/db/compaction/LeveledManifest.java
>  and comparing with behavior shown in 
> https://gist.github.com/autocracy/c95aca6b00e42215daaf, the following happens:
> Score for L1,L2,and L3 is all < 1 (paste shows 20/10 and 200/100, due to 
> incremental repair).
> Relevant code from here is
>     if (Sets.intersection(l1overlapping, compacting).size() > 0)
>         return Collections.emptyList();
> Since there will be overlap between what is compacting and L1 (in my case, 
> pushing over 1,000 tables in to L1 from L0 SCTS), I get a pile up of 1,000 
> smaller tables in L0 while awaiting the transition from L0 to L1 and destroy 
> my performance.
> Requested outcome is to continue to perform SCTS on non-compacting L0 tables.



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