Creates the appropriate instance of InputMetricsUpdater.
Creates the appropriate instance of InputMetricsUpdater.
If ReadConf.taskMetricsEnabled is true
, the created instance will be updating task metrics so
that Spark will report them in the UI. Remember that this is supported for Spark 1.2+.
If CassandraConnectorSource is registered in Spark metrics system, the created instance will be updating the included Codahale metrics. In order to register CassandraConnectorSource you need to add it to the metrics configuration file.
task context of a task for which this metrics updater is created
read configuration
allows to update Codahale metrics every the given number of rows in order to decrease overhead