/**
* This is called after reloading the allocation configuration when the scheduler is reinitilized
*
* <p>Checks to see whether any non-runnable applications become runnable now that the max running
* apps of given queue has been changed
*
* <p>Runs in O(n) where n is the number of apps that are non-runnable and in the queues that went
* from having no slack to having slack.
*/
public void updateRunnabilityOnReload() {
FSParentQueue rootQueue = scheduler.getQueueManager().getRootQueue();
List<List<FSAppAttempt>> appsNowMaybeRunnable = new ArrayList<List<FSAppAttempt>>();
gatherPossiblyRunnableAppLists(rootQueue, appsNowMaybeRunnable);
updateAppsRunnability(appsNowMaybeRunnable, Integer.MAX_VALUE);
}
/**
* Traverses the queue hierarchy under the given queue to gather all lists of non-runnable
* applications.
*/
private void gatherPossiblyRunnableAppLists(FSQueue queue, List<List<FSAppAttempt>> appLists) {
if (queue.getNumRunnableApps()
< scheduler.getAllocationConfiguration().getQueueMaxApps(queue.getName())) {
if (queue instanceof FSLeafQueue) {
appLists.add(((FSLeafQueue) queue).getCopyOfNonRunnableAppSchedulables());
} else {
for (FSQueue child : queue.getChildQueues()) {
gatherPossiblyRunnableAppLists(child, appLists);
}
}
}
}
/**
* Checks to see whether any other applications runnable now that the given application has been
* removed from the given queue. And makes them so.
*
* <p>Runs in O(n log(n)) where n is the number of queues that are under the highest queue that
* went from having no slack to having slack.
*/
public void updateRunnabilityOnAppRemoval(FSAppAttempt app, FSLeafQueue queue) {
AllocationConfiguration allocConf = scheduler.getAllocationConfiguration();
// childqueueX might have no pending apps itself, but if a queue higher up
// in the hierarchy parentqueueY has a maxRunningApps set, an app completion
// in childqueueX could allow an app in some other distant child of
// parentqueueY to become runnable.
// An app removal will only possibly allow another app to become runnable if
// the queue was already at its max before the removal.
// Thus we find the ancestor queue highest in the tree for which the app
// that was at its maxRunningApps before the removal.
FSQueue highestQueueWithAppsNowRunnable =
(queue.getNumRunnableApps() == allocConf.getQueueMaxApps(queue.getName()) - 1)
? queue
: null;
FSParentQueue parent = queue.getParent();
while (parent != null) {
if (parent.getNumRunnableApps() == allocConf.getQueueMaxApps(parent.getName()) - 1) {
highestQueueWithAppsNowRunnable = parent;
}
parent = parent.getParent();
}
List<List<FSAppAttempt>> appsNowMaybeRunnable = new ArrayList<List<FSAppAttempt>>();
// Compile lists of apps which may now be runnable
// We gather lists instead of building a set of all non-runnable apps so
// that this whole operation can be O(number of queues) instead of
// O(number of apps)
if (highestQueueWithAppsNowRunnable != null) {
gatherPossiblyRunnableAppLists(highestQueueWithAppsNowRunnable, appsNowMaybeRunnable);
}
String user = app.getUser();
Integer userNumRunning = usersNumRunnableApps.get(user);
if (userNumRunning == null) {
userNumRunning = 0;
}
if (userNumRunning == allocConf.getUserMaxApps(user) - 1) {
List<FSAppAttempt> userWaitingApps = usersNonRunnableApps.get(user);
if (userWaitingApps != null) {
appsNowMaybeRunnable.add(userWaitingApps);
}
}
updateAppsRunnability(appsNowMaybeRunnable, appsNowMaybeRunnable.size());
}