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  1. OpenNMS
  2. NMS-10352

Wrong data type for certain Cassandra JMX counters

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       MemtableSwitchCount from org.apache.cassandra.metrics.Keyspace and all the items under org.apache.cassandra.metrics.DroppedMessage are collected with GAUGE as the type.

      According to the Cassandra documentation, their types are Counter and Meter, respectively, but cassandra30x.xml specifically fetches the Count attribute for the DroppedMessage items.

      Due to this, all related values will continue to increase until Cassandra is restarted, which makes the graphs very difficult to read at a glance. Their type should be switched to counter correspondingly.

      Dropped messages using gauge:

      Dropped messages after switching to counter:

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            brynjar Brynjar Eide
            brynjar Brynjar Eide
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