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https://issues.apache.org/jira/browse/CASSANDRA-8239?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14192820#comment-14192820
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Tyler Hobbs commented on CASSANDRA-8239:
----------------------------------------
Note that due to the severity of the symptoms, I suggest we release 2.1.2 after
this is committed.
> 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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