private void schedule() {
try (SetThreadName ignored = new SetThreadName("Query-%s", queryStateMachine.getQueryId())) {
Set<StageId> completedStages = new HashSet<>();
ExecutionSchedule executionSchedule =
executionPolicy.createExecutionSchedule(stages.values());
while (!executionSchedule.isFinished()) {
List<CompletableFuture<?>> blockedStages = new ArrayList<>();
for (SqlStageExecution stage : executionSchedule.getStagesToSchedule()) {
stage.beginScheduling();
// perform some scheduling work
ScheduleResult result = stageSchedulers.get(stage.getStageId()).schedule();
// modify parent and children based on the results of the scheduling
if (result.isFinished()) {
stage.schedulingComplete();
} else if (!result.getBlocked().isDone()) {
blockedStages.add(result.getBlocked());
}
stageLinkages
.get(stage.getStageId())
.processScheduleResults(stage.getState(), result.getNewTasks());
}
// make sure to update stage linkage at least once per loop to catch async state changes
// (e.g., partial cancel)
for (SqlStageExecution stage : stages.values()) {
if (!completedStages.contains(stage.getStageId()) && stage.getState().isDone()) {
stageLinkages
.get(stage.getStageId())
.processScheduleResults(stage.getState(), ImmutableSet.of());
completedStages.add(stage.getStageId());
}
}
// wait for a state change and then schedule again
if (!blockedStages.isEmpty()) {
tryGetFutureValue(firstCompletedFuture(blockedStages), 100, MILLISECONDS);
for (CompletableFuture<?> blockedStage : blockedStages) {
blockedStage.cancel(true);
}
}
}
for (SqlStageExecution stage : stages.values()) {
StageState state = stage.getState();
if (state != SCHEDULED && state != RUNNING && !state.isDone()) {
throw new PrestoException(
INTERNAL_ERROR,
format(
"Scheduling is complete, but stage %s is in state %s",
stage.getStageId(), state));
}
}
} catch (Throwable t) {
queryStateMachine.transitionToFailed(t);
throw Throwables.propagate(t);
} finally {
RuntimeException closeError = new RuntimeException();
for (StageScheduler scheduler : stageSchedulers.values()) {
try {
scheduler.close();
} catch (Throwable t) {
queryStateMachine.transitionToFailed(t);
closeError.addSuppressed(t);
}
}
if (closeError.getSuppressed().length > 0) {
throw closeError;
}
}
}
