Pluggable metrics reporting in Cassandra 2.0.2

Apache Cassandra® introduced internal metrics exposure using the Metrics library starting from version 1.1, with a significant expansion in version 1.2 and beyond. These metrics cover cache size, hit rates, client request latency, thread pool status, per column family statistics, and other operational measurements. Since Cassandra 2.0.2, pluggable Metrics reporter support is built-in, allowing users to send these metrics to systems like Graphite or Ganglia for data storage and graphing. The metrics can be customized by including or excluding specific groups of metrics based on the cluster's requirements. These metrics are useful for monitoring and troubleshooting performance issues in a Cassandra cluster.