Boring but parallel loops in Scala using "for" keyword

aws_sdk_v2_ecs_config_for_keyword.scala

import java.util.concurrent.TimeUnit

import software.amazon.awssdk.services.ecs.EcsClient
import software.amazon.awssdk.services.ecs.model.{DescribeServicesRequest, ListServicesRequest}

import scala.collection.JavaConverters._

object EcsAutoScalingReport extends App {
  val startTime = System.nanoTime()

  var ecs = EcsClient.create()
  // 92 services collected in
  // Sequential: 11/14/7/13/12/15 secs
  // 1 Parallel For: 9/10/10/10 secs
  // 2 Parallel For: 5/5/5/5/6 secs
  // 3 Parallel For: 5/6/5/5/5 secs
  for (ecsClusterArn <- ecs.listClustersPaginator().clusterArns().asScala.par) {
    for (ecsServiceArns <- ecs.listServicesPaginator(ListServicesRequest.builder()
      .cluster(ecsClusterArn)
      .build())
      .serviceArns().asScala.grouped(10).toParArray) {
      for (ecsService <- ecs.describeServices(DescribeServicesRequest.builder()
        .cluster(ecsClusterArn)
        .services(ecsServiceArns.asJavaCollection)
        .build())
        .services().asScala) {
        println(ecsService.serviceName())
      }
    }
  }
  val timeTakenSec = TimeUnit.NANOSECONDS.toSeconds(System.nanoTime() - startTime)
  println(s"DONE in $timeTakenSec secs")
}