@Override
public void step() {
if (this.isFinished()) {
return;
}
if (openedList.isEmpty()) {
this.isFinished = true;
this.isRunning = false;
return;
}
Node curr = openedList.pop();
for (Map.Entry<Direction, Link> item : curr.links.entrySet()) {
Direction dir = item.getKey();
Link link = item.getValue();
Node next = link.n1 == curr ? link.n2 : link.n1;
if (next == goal) {
parentMap.put(next, curr);
createPath();
return;
}
if (closedList.contains(next)) {
// do nothing or reopen?
} else if (openedList.contains(next)) {
// do nothing?
} else {
openedList.addFirst(next);
parentMap.put(next, curr);
}
}
closedList.add(curr);
steps++;
}
/**
* Receives an AcknowledgeCheckpoint message and returns whether the message was associated with a
* pending checkpoint.
*
* @param message Checkpoint ack from the task manager
* @return Flag indicating whether the ack'd checkpoint was associated with a pending checkpoint.
* @throws Exception If the checkpoint cannot be added to the completed checkpoint store.
*/
public boolean receiveAcknowledgeMessage(AcknowledgeCheckpoint message) throws Exception {
if (shutdown || message == null) {
return false;
}
if (!job.equals(message.getJob())) {
LOG.error("Received AcknowledgeCheckpoint message for wrong job: {}", message);
return false;
}
final long checkpointId = message.getCheckpointId();
CompletedCheckpoint completed = null;
PendingCheckpoint checkpoint;
// Flag indicating whether the ack message was for a known pending
// checkpoint.
boolean isPendingCheckpoint;
synchronized (lock) {
// we need to check inside the lock for being shutdown as well, otherwise we
// get races and invalid error log messages
if (shutdown) {
return false;
}
checkpoint = pendingCheckpoints.get(checkpointId);
if (checkpoint != null && !checkpoint.isDiscarded()) {
isPendingCheckpoint = true;
if (checkpoint.acknowledgeTask(
message.getTaskExecutionId(),
message.getState(),
message.getStateSize(),
null)) { // TODO: Give KV-state to the acknowledgeTask method
if (checkpoint.isFullyAcknowledged()) {
completed = checkpoint.toCompletedCheckpoint();
completedCheckpointStore.addCheckpoint(completed);
LOG.info(
"Completed checkpoint "
+ checkpointId
+ " (in "
+ completed.getDuration()
+ " ms)");
if (LOG.isDebugEnabled()) {
StringBuilder builder = new StringBuilder();
for (Map.Entry<JobVertexID, TaskState> entry : completed.getTaskStates().entrySet()) {
builder
.append("JobVertexID: ")
.append(entry.getKey())
.append(" {")
.append(entry.getValue())
.append("}");
}
LOG.debug(builder.toString());
}
pendingCheckpoints.remove(checkpointId);
rememberRecentCheckpointId(checkpointId);
dropSubsumedCheckpoints(completed.getTimestamp());
onFullyAcknowledgedCheckpoint(completed);
triggerQueuedRequests();
}
} else {
// checkpoint did not accept message
LOG.error(
"Received duplicate or invalid acknowledge message for checkpoint "
+ checkpointId
+ " , task "
+ message.getTaskExecutionId());
}
} else if (checkpoint != null) {
// this should not happen
throw new IllegalStateException(
"Received message for discarded but non-removed checkpoint " + checkpointId);
} else {
// message is for an unknown checkpoint, or comes too late (checkpoint disposed)
if (recentPendingCheckpoints.contains(checkpointId)) {
isPendingCheckpoint = true;
LOG.warn("Received late message for now expired checkpoint attempt " + checkpointId);
} else {
isPendingCheckpoint = false;
}
}
}
// send the confirmation messages to the necessary targets. we do this here
// to be outside the lock scope
if (completed != null) {
final long timestamp = completed.getTimestamp();
for (ExecutionVertex ev : tasksToCommitTo) {
Execution ee = ev.getCurrentExecutionAttempt();
if (ee != null) {
ExecutionAttemptID attemptId = ee.getAttemptId();
NotifyCheckpointComplete notifyMessage =
new NotifyCheckpointComplete(job, attemptId, checkpointId, timestamp);
ev.sendMessageToCurrentExecution(notifyMessage, ee.getAttemptId());
}
}
statsTracker.onCompletedCheckpoint(completed);
}
return isPendingCheckpoint;
}
/**
* Receives a {@link DeclineCheckpoint} message and returns whether the message was associated
* with a pending checkpoint.
*
* @param message Checkpoint decline from the task manager
* @return Flag indicating whether the declined checkpoint was associated with a pending
* checkpoint.
*/
public boolean receiveDeclineMessage(DeclineCheckpoint message) throws Exception {
if (shutdown || message == null) {
return false;
}
if (!job.equals(message.getJob())) {
LOG.error("Received DeclineCheckpoint message for wrong job: {}", message);
return false;
}
final long checkpointId = message.getCheckpointId();
PendingCheckpoint checkpoint;
// Flag indicating whether the ack message was for a known pending
// checkpoint.
boolean isPendingCheckpoint;
synchronized (lock) {
// we need to check inside the lock for being shutdown as well, otherwise we
// get races and invalid error log messages
if (shutdown) {
return false;
}
checkpoint = pendingCheckpoints.get(checkpointId);
if (checkpoint != null && !checkpoint.isDiscarded()) {
isPendingCheckpoint = true;
LOG.info(
"Discarding checkpoint "
+ checkpointId
+ " because of checkpoint decline from task "
+ message.getTaskExecutionId());
pendingCheckpoints.remove(checkpointId);
checkpoint.discard(userClassLoader);
rememberRecentCheckpointId(checkpointId);
boolean haveMoreRecentPending = false;
Iterator<Map.Entry<Long, PendingCheckpoint>> entries =
pendingCheckpoints.entrySet().iterator();
while (entries.hasNext()) {
PendingCheckpoint p = entries.next().getValue();
if (!p.isDiscarded()
&& p.getCheckpointTimestamp() >= checkpoint.getCheckpointTimestamp()) {
haveMoreRecentPending = true;
break;
}
}
if (!haveMoreRecentPending && !triggerRequestQueued) {
LOG.info("Triggering new checkpoint because of discarded checkpoint " + checkpointId);
triggerCheckpoint(System.currentTimeMillis());
} else if (!haveMoreRecentPending) {
LOG.info(
"Promoting queued checkpoint request because of discarded checkpoint "
+ checkpointId);
triggerQueuedRequests();
}
} else if (checkpoint != null) {
// this should not happen
throw new IllegalStateException(
"Received message for discarded but non-removed checkpoint " + checkpointId);
} else {
// message is for an unknown checkpoint, or comes too late (checkpoint disposed)
if (recentPendingCheckpoints.contains(checkpointId)) {
isPendingCheckpoint = true;
LOG.info(
"Received another decline checkpoint message for now expired checkpoint attempt "
+ checkpointId);
} else {
isPendingCheckpoint = false;
}
}
}
return isPendingCheckpoint;
}