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https://issues.apache.org/jira/browse/CASSANDRA-7731?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14098700#comment-14098700
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Jeremiah Jordan commented on CASSANDRA-7731:
--------------------------------------------

LGTM +1

> Get max values for live/tombstone cells per slice
> -------------------------------------------------
>
>                 Key: CASSANDRA-7731
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-7731
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Core
>            Reporter: Cyril Scetbon
>            Assignee: Robert Stupp
>            Priority: Minor
>             Fix For: 2.0.11, 2.1.1
>
>         Attachments: 7731-2.0.txt, 7731-2.1.txt
>
>
> I think you should not say that slice statistics are valid for the [last five 
> minutes 
> |https://github.com/apache/cassandra/blob/cassandra-2.0/src/java/org/apache/cassandra/tools/NodeCmd.java#L955-L956]
>  in CFSTATS command of nodetool. I've read the documentation from yammer for 
> Histograms and there is no way to force values to expire after x minutes 
> except by 
> [clearing|http://grepcode.com/file/repo1.maven.org/maven2/com.yammer.metrics/metrics-core/2.1.2/com/yammer/metrics/core/Histogram.java#96]
>  it . The only thing I can see is that the last snapshot used to provide the 
> median (or whatever you'd used instead) value is based on 1028 values.
> I think we should also be able to detect that some requests are accessing a 
> lot of live/tombstone cells per query and that's not possible for now without 
> activating DEBUG for SliceQueryFilter for example and by tweaking the 
> threshold. Currently as nodetool cfstats returns the median if a low part of 
> the queries are scanning a lot of live/tombstone cells we miss it !



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