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https://issues.apache.org/jira/browse/CASSANDRA-8239?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14193121#comment-14193121
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Aleksey Yeschenko commented on CASSANDRA-8239:
----------------------------------------------

+1

> NamesQueryFilters do not update SSTable read rate metrics
> ---------------------------------------------------------
>
>                 Key: CASSANDRA-8239
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-8239
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>            Reporter: Tyler Hobbs
>            Assignee: Tyler Hobbs
>            Priority: Blocker
>             Fix For: 2.1.2
>
>         Attachments: 8239.txt
>
>
> In {{CollationController.collectionTimeOrderedData()}}, we are not calling 
> {{sstable.incrementReadCount()}}.  If a table is queried exclusively with 
> these types of queries, its read meter will never be updated.  Since 
> SizeTieredCompactionStrategy depends on the read meter for omitting cold 
> sstables form compaction, this can result in no compactions being performed.  
> (I believe this would require an occasional non-NamesQueryFilter query to 
> happen, because if all of the readMeters have a rate of 0.0, compaction will 
> proceed normally.)  The IndexSummaryManager is also affected.
> A workaround for compactions not occurring is to run the following:
> {noformat}
> ALTER TABLE <tablename> WITH compaction = {'class': 
> 'SizeTieredCompactionStrategy', 'min_threshold': '4', 'max_threshold': '32', 
> 'cold_reads_to_omit': 0.0};
> {noformat}



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