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https://issues.apache.org/jira/browse/CASSANDRA-8860?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14341913#comment-14341913
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Jonathan Ellis edited comment on CASSANDRA-8860 at 3/1/15 3:23 AM:
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That's a lot of complexity for something whose benefit I'm unclear on (I'm 
talking about the "ignore cold sstables" feature).

To the best of my knowledge, CASSANDRA-8635 has never been observed as a 
problem in the wild.  I'd be in favor of reverting it and documenting "don't 
enable cold sstable elision if you do a lot of overwrites."


was (Author: jbellis):
That's a lot of complexity for something whose benefit I'm unclear on (I'm 
talking about the "ignore cold sstables feature").

To the best of my knowledge, CASSANDRA-8635 has never been observed as a 
problem in the wild.  I'd be in favor of reverting it and documenting "don't 
enable cold sstable elision if you do a lot of overwrites."

> Too many java.util.HashMap$Entry objects in heap
> ------------------------------------------------
>
>                 Key: CASSANDRA-8860
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-8860
>             Project: Cassandra
>          Issue Type: Bug
>         Environment: Cassandra 2.1.3, jdk 1.7u51
>            Reporter: Phil Yang
>            Assignee: Phil Yang
>             Fix For: 2.1.4
>
>         Attachments: 8860-v2.txt, 8860.txt, cassandra-env.sh, cassandra.yaml, 
> jmap.txt, jstack.txt, jstat-afterv1.txt, jstat-afterv2.txt, jstat-before.txt
>
>
> While I upgrading my cluster to 2.1.3, I find some nodes (not all) may have 
> GC issue after the node restarting successfully. Old gen grows very fast and 
> most of the space can not be recycled after setting its status to normal 
> immediately. The qps of both reading and writing are very low and there is no 
> heavy compaction.
> Jmap result seems strange that there are too many java.util.HashMap$Entry 
> objects in heap, where in my experience the "[B" is usually the No1.
> If I downgrade it to 2.1.1, this issue will not appear.
> I uploaded conf files and jstack/jmap outputs. I'll upload heap dump if 
> someone need it.



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