com.hazelcast.internal.diagnostics.OperationThreadSamplerPlugin Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2024, Hazelcast, Inc. All Rights Reserved.
*
* Licensed 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 com.hazelcast.internal.diagnostics;
import com.hazelcast.spi.impl.operationservice.NamedOperation;
import com.hazelcast.internal.util.concurrent.ConcurrentItemCounter;
import com.hazelcast.spi.impl.NodeEngineImpl;
import com.hazelcast.spi.impl.operationexecutor.OperationExecutor;
import com.hazelcast.spi.impl.operationexecutor.OperationRunner;
import com.hazelcast.spi.impl.operationservice.impl.OperationServiceImpl;
import com.hazelcast.spi.properties.HazelcastProperties;
import com.hazelcast.spi.properties.HazelcastProperty;
import java.util.concurrent.locks.LockSupport;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import static java.util.concurrent.TimeUnit.SECONDS;
/**
* The OperationThreadSamplerPlugin is a {@link DiagnosticsPlugin} that samples the
* operations threads and checks with operations/tasks are running. We have
* the slow operation detector; which is very useful for very slow operations.
* But it isn't useful for high volumes of not too slow operations.
*
* With the operation sampler we have a lot better understanding which operations
* are actually running.
*/
public class OperationThreadSamplerPlugin extends DiagnosticsPlugin {
/**
* The sample period in seconds.
*
* This is the frequency it will dump content to file. It isn't the frequency
* that the operations are being sampled.
*
*
* If set to 0, the plugin is disabled.
*/
public static final HazelcastProperty PERIOD_SECONDS
= new HazelcastProperty("hazelcast.diagnostics.operationthreadsamples.period.seconds", 0, SECONDS);
/**
* The period in milliseconds between taking samples.
*
* The lower the period, the higher the overhead, but also the higher the
* precision.
*/
public static final HazelcastProperty SAMPLER_PERIOD_MILLIS
= new HazelcastProperty("hazelcast.diagnostics.operationthreadsamples.sampler.period.millis", 100, MILLISECONDS);
/**
* If the name the data-structure the operation operates on should be included.
*
* WARNING: This feature should not be used in production because it can lead to
* quite a lot of litter and it can lead to uncontrolled memory growth because the
* samples of old data-structures will not be removed.
*
* Also each time the samples are taken, quite a lot of litter can be generated. So
* probably you do not want to have a too low SAMPLER_PERIOD_MILLIS because the lower
* it gets, the more litter is created.
*/
public static final HazelcastProperty INCLUDE_NAME
= new HazelcastProperty("hazelcast.diagnostics.operationthreadsamples.includeName", false);
public static final float HUNDRED = 100f;
protected final long samplerPeriodMillis;
protected final ConcurrentItemCounter partitionSpecificSamples = new ConcurrentItemCounter<>();
protected final ConcurrentItemCounter genericSamples = new ConcurrentItemCounter<>();
protected final OperationExecutor executor;
protected final NodeEngineImpl nodeEngine;
protected final boolean includeName;
private final long periodMillis;
public OperationThreadSamplerPlugin(NodeEngineImpl nodeEngine) {
super(nodeEngine.getLogger(OperationThreadSamplerPlugin.class));
this.nodeEngine = nodeEngine;
OperationServiceImpl operationService = nodeEngine.getOperationService();
this.executor = ((OperationServiceImpl) operationService).getOperationExecutor();
HazelcastProperties props = nodeEngine.getProperties();
this.periodMillis = props.getMillis(PERIOD_SECONDS);
this.samplerPeriodMillis = props.getMillis(SAMPLER_PERIOD_MILLIS);
this.includeName = props.getBoolean(INCLUDE_NAME);
}
@Override
public long getPeriodMillis() {
return periodMillis;
}
@Override
public void onStart() {
logger.info("Plugin:active: period-millis:" + periodMillis + " sampler-period-millis:" + samplerPeriodMillis);
new SampleThread().start();
}
@Override
public void run(DiagnosticsLogWriter writer) {
writer.startSection("OperationThreadSamples");
write(writer, "Partition", partitionSpecificSamples);
write(writer, "Generic", genericSamples);
writer.endSection();
}
private void write(DiagnosticsLogWriter writer, String text, ConcurrentItemCounter samples) {
writer.startSection(text);
long total = samples.total();
for (String name : samples.keySet()) {
long s = samples.get(name);
String entryStr = total == 0L ? String.valueOf(s) : (s + " " + (HUNDRED * s / total) + "%");
writer.writeKeyValueEntry(name, entryStr);
}
writer.endSection();
}
protected class SampleThread extends Thread {
@Override
public void run() {
long nextRunMillis = System.currentTimeMillis();
while (nodeEngine.isRunning()) {
LockSupport.parkUntil(nextRunMillis);
nextRunMillis = samplerPeriodMillis;
sample(executor.getPartitionOperationRunners(), partitionSpecificSamples);
sample(executor.getGenericOperationRunners(), genericSamples);
}
}
private void sample(OperationRunner[] runners, ConcurrentItemCounter samples) {
for (OperationRunner runner : runners) {
Object task = runner.currentTask();
if (task != null) {
samples.inc(toKey(task));
}
}
}
private String toKey(Object task) {
String name;
if (includeName) {
if (task instanceof NamedOperation operation) {
name = task.getClass().getName() + "#" + operation.getName();
} else {
name = task.getClass().getName();
}
} else {
name = task.getClass().getName();
}
return name;
}
}
}