/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.flink.runtime.checkpoint;
import org.apache.flink.runtime.jobgraph.JobVertexID;
import javax.annotation.Nullable;
import java.util.HashMap;
import java.util.Map;
import static org.apache.flink.util.Preconditions.checkNotNull;
/**
* Statistics for a pending checkpoint that is still in progress.
*
* <p>This is the starting point for all checkpoint tracking. The life cycle
* of instances of this class is tightly coupled to a {@link PendingCheckpoint}
* instance, which forwards statistics about acknowledged subtasks
* via {@link #reportSubtaskStats(JobVertexID, SubtaskStateStats)}.
*
* <p>Depending on whether the {@link PendingCheckpoint} is finalized
* successfully or aborted, we replace ourselves with a {@link CompletedCheckpointStats}
* or {@link FailedCheckpointStats} and notify the {@link CheckpointStatsTracker}.
*
* <p>The statistics gathered here are all live updated.
*/
public class PendingCheckpointStats extends AbstractCheckpointStats {
private static final long serialVersionUID = -973959257699390327L;
/** Tracker callback when the pending checkpoint is finalized or aborted. */
private transient final CheckpointStatsTracker.PendingCheckpointStatsCallback trackerCallback;
/** The current number of acknowledged subtasks. */
private volatile int currentNumAcknowledgedSubtasks;
/** Current checkpoint state size over all collected subtasks. */
private volatile long currentStateSize;
/** Current buffered bytes during alignment over all collected subtasks. */
private volatile long currentAlignmentBuffered;
/** Stats of the latest acknowleged subtask. */
private volatile SubtaskStateStats latestAcknowledgedSubtask;
/**
* Creates a tracker for a {@link PendingCheckpoint}.
*
* @param checkpointId ID of the checkpoint.
* @param triggerTimestamp Timestamp when the checkpoint was triggered.
* @param props Checkpoint properties of the checkpoint.
* @param totalSubtaskCount Total number of subtasks for the checkpoint.
* @param taskStats Task stats for each involved operator.
* @param trackerCallback Callback for the {@link CheckpointStatsTracker}.
*/
PendingCheckpointStats(
long checkpointId,
long triggerTimestamp,
CheckpointProperties props,
int totalSubtaskCount,
Map<JobVertexID, TaskStateStats> taskStats,
CheckpointStatsTracker.PendingCheckpointStatsCallback trackerCallback) {
super(checkpointId, triggerTimestamp, props, totalSubtaskCount, taskStats);
this.trackerCallback = checkNotNull(trackerCallback);
}
@Override
public CheckpointStatsStatus getStatus() {
return CheckpointStatsStatus.IN_PROGRESS;
}
@Override
public int getNumberOfAcknowledgedSubtasks() {
return currentNumAcknowledgedSubtasks;
}
@Override
public long getStateSize() {
return currentStateSize;
}
@Override
public long getAlignmentBuffered() {
return currentAlignmentBuffered;
}
@Override
public SubtaskStateStats getLatestAcknowledgedSubtaskStats() {
return latestAcknowledgedSubtask;
}
// ------------------------------------------------------------------------
// Callbacks from the PendingCheckpoint instance
// ------------------------------------------------------------------------
/**
* Reports statistics for a single subtask.
*
* @param jobVertexId ID of the task/operator the subtask belongs to.
* @param subtask The statistics for the subtask.
* @return <code>true</code> if successfully reported or <code>false</code> otherwise.
*/
boolean reportSubtaskStats(JobVertexID jobVertexId, SubtaskStateStats subtask) {
TaskStateStats taskStateStats = taskStats.get(jobVertexId);
if (taskStateStats != null && taskStateStats.reportSubtaskStats(subtask)) {
currentNumAcknowledgedSubtasks++;
latestAcknowledgedSubtask = subtask;
currentStateSize += subtask.getStateSize();
long alignmentBuffered = subtask.getAlignmentBuffered();
if (alignmentBuffered > 0) {
currentAlignmentBuffered += alignmentBuffered;
}
return true;
} else {
return false;
}
}
/**
* Reports a successfully completed pending checkpoint.
*
* @param externalPath Optional external storage path if checkpoint was externalized.
* @return Callback for the {@link CompletedCheckpoint} instance to notify about disposal.
*/
CompletedCheckpointStats.DiscardCallback reportCompletedCheckpoint(@Nullable String externalPath) {
CompletedCheckpointStats completed = new CompletedCheckpointStats(
checkpointId,
triggerTimestamp,
props,
numberOfSubtasks,
new HashMap<>(taskStats),
currentNumAcknowledgedSubtasks,
currentStateSize,
currentAlignmentBuffered,
latestAcknowledgedSubtask,
externalPath);
trackerCallback.reportCompletedCheckpoint(completed);
return completed.getDiscardCallback();
}
/**
* Reports a failed pending checkpoint.
*
* @param failureTimestamp Timestamp of the failure.
* @param cause Optional cause of the failure.
*/
void reportFailedCheckpoint(long failureTimestamp, @Nullable Throwable cause) {
FailedCheckpointStats failed = new FailedCheckpointStats(
checkpointId,
triggerTimestamp,
props,
numberOfSubtasks,
new HashMap<>(taskStats),
currentNumAcknowledgedSubtasks,
currentStateSize,
currentAlignmentBuffered,
failureTimestamp,
latestAcknowledgedSubtask,
cause);
trackerCallback.reportFailedCheckpoint(failed);
}
@Override
public String toString() {
return "PendingCheckpoint(id=" + getCheckpointId() + ")";
}
}