Dear Cassandra users,
Some feedback is needed from your side, as the change itself is
related to the way the internal metrics can be exported from the
Cassandra node. If you are not using the metrics-reporter-config [1]
and exporting metrics to the physical file provided by it, no action
is required from your side. Please, note that this library is not
related to the dropwizard metrics library, everything related to the
latter library remains the same.
We are trying to clean up obsolete dependencies, that are no longer in
use and make the next upcoming 5.0 release safer from all
perspectives. Currently, Cassandra provides a pluggable metrics
reporter called metrics-reporter-config to export internal metrics,
mostly reflected in JMX Beans, to a file, and this functionality is
configured using the Cassandra.metricsReporterConfigFile system
property which points to the metrics-reporter configuration file.
The way that metrics can be exported is fully covered by the
dropwizard metrics library itself, using e.g. CsvReporter [2], which
has been a part of Cassandra for a long time, and, in fact, the
metrics-reporter-config [1], which has been in the archive for almost
3 years, was not deprecated earlier in Cassandra 4.x only because of
lack of attention to it.
We want to fix this and remove the dependency on
metrics-reporter-config library [1] support starting with the 5.0
release. Please let me know if the following removal affects you in
any way by replying to this message or by posting to the related JIRA
issue [3]. In addition, we want to get rid of the commons-codec
dependency [4] that was used to put metrics reported by the
metrics-reporter-config into the InfluxDB.
If you have any concerns/questions, please let me know.
[1] https://github.com/addthis/metrics-reporter-config
[2] https://metrics.dropwizard.io/4.2.0/getting-started.html#other-reporting
[3] https://issues.apache.org/jira/browse/CASSANDRA-18743
[4] https://issues.apache.org/jira/browse/CASSANDRA-18772
