Github user kayousterhout commented on a diff in the pull request:
https://github.com/apache/spark/pull/3779#discussion_r24065817
--- Diff:
core/src/main/scala/org/apache/spark/scheduler/TaskSetManager.scala ---
@@ -506,13 +506,59 @@ private[spark] class TaskSetManager(
* Get the level we can launch tasks according to delay scheduling,
based on current wait time.
*/
private def getAllowedLocalityLevel(curTime: Long):
TaskLocality.TaskLocality = {
- while (curTime - lastLaunchTime >= localityWaits(currentLocalityIndex)
&&
- currentLocalityIndex < myLocalityLevels.length - 1)
- {
- // Jump to the next locality level, and remove our waiting time for
the current one since
- // we don't want to count it again on the next one
- lastLaunchTime += localityWaits(currentLocalityIndex)
- currentLocalityIndex += 1
+ // Remove the scheduled or finished tasks lazily
+ def hasNotScheduledTasks(taskIndexes: ArrayBuffer[Int]): Boolean = {
+ var indexOffset = taskIndexes.size
+ while (indexOffset > 0) {
+ indexOffset -= 1
+ val index = taskIndexes(indexOffset)
+ if (copiesRunning(index) == 0 && !successful(index)) {
+ return true
+ } else {
+ taskIndexes.remove(indexOffset)
+ }
+ }
+ false
+ }
+ // It removes the empty lists after check
+ def hasMoreTasks(pendingTasks: HashMap[String, ArrayBuffer[Int]]):
Boolean = {
+ val emptyKeys = new ArrayBuffer[String]
+ val hasTasks = pendingTasks.exists{
+ case (id: String, tasks: ArrayBuffer[Int]) =>
+ if (hasNotScheduledTasks(tasks)) {
+ true
+ } else {
+ emptyKeys += id
+ false
+ }
+ }
+ emptyKeys.foreach(x => pendingTasks.remove(x))
+ hasTasks
+ }
+
+ while (currentLocalityIndex < myLocalityLevels.length - 1) {
+ val moreTasks = myLocalityLevels(currentLocalityIndex) match {
+ case TaskLocality.PROCESS_LOCAL =>
hasMoreTasks(pendingTasksForExecutor)
+ case TaskLocality.NODE_LOCAL => hasMoreTasks(pendingTasksForHost)
+ case TaskLocality.NO_PREF => pendingTasksWithNoPrefs.isEmpty
+ case TaskLocality.RACK_LOCAL => hasMoreTasks(pendingTasksForRack)
+ }
+ if (!moreTasks) {
+ // Move to next locality level if there is no task for current
level
+ lastLaunchTime = curTime
+ logDebug(s"No tasks for locality level
${myLocalityLevels(currentLocalityIndex)} " +
+ s"move to ${myLocalityLevels(currentLocalityIndex + 1)}")
+ currentLocalityIndex += 1
+ } else if (curTime - lastLaunchTime >=
localityWaits(currentLocalityIndex)) {
+ // Jump to the next locality level, and remove our waiting time
for the current one since
+ // we don't want to count it again on the next one
+ lastLaunchTime += localityWaits(currentLocalityIndex)
+ currentLocalityIndex += 1
+ logDebug(s"Move to ${myLocalityLevels(currentLocalityIndex)} after
wait for " +
+ s"${localityWaits(currentLocalityIndex)} ms")
+ } else {
+ return myLocalityLevels(currentLocalityIndex)
+ }
--- End diff --
It would also help to write a slightly longer / more informative comment in
place of "It removes.." and "Remove the scheduled...". What about adding the
following before noMoreTasksToRun:
"Walk through the list of tasks that can be scheduled at each location and
returns true if there are any tasks that still need to be scheduled. Lazily
cleans up tasks that have already been scheduled."
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at [email protected] or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
