org.apache.flink.runtime.rest.handler.legacy.backpressure.OperatorBackPressureStats Maven / Gradle / Ivy
/*
* 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.rest.handler.legacy.backpressure;
import java.io.Serializable;
import java.util.Arrays;
import static org.apache.flink.util.Preconditions.checkArgument;
import static org.apache.flink.util.Preconditions.checkNotNull;
/**
* Back pressure statistics of multiple tasks.
*
* Statistics are gathered by sampling stack traces of running tasks. The
* back pressure ratio denotes the ratio of traces indicating back pressure
* to the total number of sampled traces.
*/
public class OperatorBackPressureStats implements Serializable {
private static final long serialVersionUID = 1L;
/** ID of the corresponding sample. */
private final int sampleId;
/** End time stamp of the corresponding sample. */
private final long endTimestamp;
/** Back pressure ratio per subtask. */
private final double[] subTaskBackPressureRatio;
/** Maximum back pressure ratio. */
private final double maxSubTaskBackPressureRatio;
public OperatorBackPressureStats(
int sampleId,
long endTimestamp,
double[] subTaskBackPressureRatio) {
this.sampleId = sampleId;
this.endTimestamp = endTimestamp;
this.subTaskBackPressureRatio = checkNotNull(subTaskBackPressureRatio, "Sub task back pressure ratio");
checkArgument(subTaskBackPressureRatio.length >= 1, "No Sub task back pressure ratio specified");
double max = 0;
for (double ratio : subTaskBackPressureRatio) {
if (ratio > max) {
max = ratio;
}
}
maxSubTaskBackPressureRatio = max;
}
/**
* Returns the ID of the sample.
*
* @return ID of the sample
*/
public int getSampleId() {
return sampleId;
}
/**
* Returns the time stamp, when all stack traces were collected at the
* JobManager.
*
* @return Time stamp, when all stack traces were collected at the
* JobManager
*/
public long getEndTimestamp() {
return endTimestamp;
}
/**
* Returns the number of sub tasks.
*
* @return Number of sub tasks.
*/
public int getNumberOfSubTasks() {
return subTaskBackPressureRatio.length;
}
/**
* Returns the ratio of stack traces indicating back pressure to total
* number of sampled stack traces.
*
* @param index Subtask index.
*
* @return Ratio of stack traces indicating back pressure to total number
* of sampled stack traces.
*/
public double getBackPressureRatio(int index) {
return subTaskBackPressureRatio[index];
}
/**
* Returns the maximum back pressure ratio of all sub tasks.
*
* @return Maximum back pressure ratio of all sub tasks.
*/
public double getMaxBackPressureRatio() {
return maxSubTaskBackPressureRatio;
}
@Override
public String toString() {
return "OperatorBackPressureStats{" +
"sampleId=" + sampleId +
", endTimestamp=" + endTimestamp +
", subTaskBackPressureRatio=" + Arrays.toString(subTaskBackPressureRatio) +
'}';
}
}