Examples with BlockedReason com.facebook.presto.execution.scheduler.ScheduleResult.BlockedReason used on opensource projects

Example 1 with BlockedReason

use of com.facebook.presto.execution.scheduler.ScheduleResult.BlockedReason in project presto by prestodb.

the class FixedSourcePartitionedScheduler method schedule.

@Override
public ScheduleResult schedule() {
    // schedule a task on every node in the distribution
    List<RemoteTask> newTasks = ImmutableList.of();
    if (!scheduledTasks) {
        newTasks = Streams.mapWithIndex(nodes.stream(), (node, id) -> stage.scheduleTask(node, toIntExact(id))).filter(Optional::isPresent).map(Optional::get).collect(toImmutableList());
        scheduledTasks = true;
        // notify listeners that we have scheduled all tasks so they can set no more buffers or exchange splits
        stage.transitionToFinishedTaskScheduling();
    }
    boolean allBlocked = true;
    List<ListenableFuture<?>> blocked = new ArrayList<>();
    BlockedReason blockedReason = BlockedReason.NO_ACTIVE_DRIVER_GROUP;
    if (groupedLifespanScheduler.isPresent()) {
        while (!tasksToRecover.isEmpty()) {
            if (anySourceSchedulingFinished) {
                throw new IllegalStateException("Recover after any source scheduling finished is not supported");
            }
            groupedLifespanScheduler.get().onTaskFailed(tasksToRecover.poll(), sourceSchedulers);
        }
        if (groupedLifespanScheduler.get().allLifespanExecutionFinished()) {
            for (SourceScheduler sourceScheduler : sourceSchedulers) {
                sourceScheduler.notifyAllLifespansFinishedExecution();
            }
        } else {
            // Start new driver groups on the first scheduler if necessary,
            // i.e. when previous ones have finished execution (not finished scheduling).
            // 
            // Invoke schedule method to get a new SettableFuture every time.
            // Reusing previously returned SettableFuture could lead to the ListenableFuture retaining too many listeners.
            blocked.add(groupedLifespanScheduler.get().schedule(sourceSchedulers.get(0)));
        }
    }
    int splitsScheduled = 0;
    Iterator<SourceScheduler> schedulerIterator = sourceSchedulers.iterator();
    List<Lifespan> driverGroupsToStart = ImmutableList.of();
    while (schedulerIterator.hasNext()) {
        synchronized (this) {
            // prevent that by checking if scheduling has been cancelled first.
            if (closed) {
                break;
            }
            SourceScheduler sourceScheduler = schedulerIterator.next();
            for (Lifespan lifespan : driverGroupsToStart) {
                sourceScheduler.startLifespan(lifespan, partitionHandleFor(lifespan));
            }
            ScheduleResult schedule = sourceScheduler.schedule();
            if (schedule.getSplitsScheduled() > 0) {
                stage.transitionToSchedulingSplits();
            }
            splitsScheduled += schedule.getSplitsScheduled();
            if (schedule.getBlockedReason().isPresent()) {
                blocked.add(schedule.getBlocked());
                blockedReason = blockedReason.combineWith(schedule.getBlockedReason().get());
            } else {
                verify(schedule.getBlocked().isDone(), "blockedReason not provided when scheduler is blocked");
                allBlocked = false;
            }
            driverGroupsToStart = sourceScheduler.drainCompletelyScheduledLifespans();
            if (schedule.isFinished()) {
                stage.schedulingComplete(sourceScheduler.getPlanNodeId());
                sourceSchedulers.remove(sourceScheduler);
                sourceScheduler.close();
                anySourceSchedulingFinished = true;
            }
        }
    }
    if (allBlocked) {
        return ScheduleResult.blocked(sourceSchedulers.isEmpty(), newTasks, whenAnyComplete(blocked), blockedReason, splitsScheduled);
    } else {
        return ScheduleResult.nonBlocked(sourceSchedulers.isEmpty(), newTasks, splitsScheduled);
    }
}