org.apache.spark.metrics.MetricsUpdater.scala Maven / Gradle / Ivy
package org.apache.spark.metrics
import com.codahale.metrics.Timer.Context
import org.apache.spark.{SparkEnv, TaskContext}
/** The base trait for metrics updaters implementations. The metrics updater is an object which provides
* a unified way to update all the relevant metrics which are collected for the particular type of
* activity. The connector provides `InputMetricsUpdater` and `OutputMetricsUpdater` which are aimed
* to update all the read and write metrics respectively. */
trait MetricsUpdater {
/** A method to be called when the task is finished. It stops the task timer and flushes data. */
def finish(): Long
}
object MetricsUpdater {
val cassandraConnectorSourceName = "cassandra-connector"
def getSource(taskContext: TaskContext): Option[CassandraConnectorSource] =
taskContext
.getMetricsSources(cassandraConnectorSourceName).headOption
.map(_.asInstanceOf[CassandraConnectorSource])
}
/** Timer mixin allows to measure the time of a task - or, in other words - the time from creating an
* instance to calling `com.codahale.metrics.Timer.Context.stop` method. */
trait Timer {
def stopTimer(): Long
}
trait SimpleTimer extends Timer {
private val startTime = System.nanoTime()
override def stopTimer(): Long = System.nanoTime() - startTime
}
trait CCSTimer extends Timer {
def source: CassandraConnectorSource
val timer: Context
override def stopTimer(): Long = {
val t = timer.stop()
Option(SparkEnv.get).flatMap(env => Option(env.metricsSystem)).foreach(_.report())
t
}
}