/*
* 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.geode.distributed.internal;
import org.apache.logging.log4j.Logger;
import org.apache.geode.admin.GemFireHealth;
import org.apache.geode.admin.GemFireHealthConfig;
import org.apache.geode.admin.internal.GemFireHealthEvaluator;
import org.apache.geode.distributed.internal.membership.InternalDistributedMember;
import org.apache.geode.internal.admin.remote.HealthListenerMessage;
import org.apache.geode.internal.i18n.LocalizedStrings;
import org.apache.geode.internal.logging.LogService;
import org.apache.geode.internal.logging.LoggingThreadGroup;
import org.apache.geode.internal.logging.log4j.LocalizedMessage;
/**
* Implements a thread that monitors the health of the vm it lives in.
*
* @since GemFire 3.5
*/
public class HealthMonitorImpl implements HealthMonitor, Runnable {
private static final Logger logger = LogService.getLogger();
private final InternalDistributedMember owner;
private final int id;
private final DistributionManager dm;
private final GemFireHealthEvaluator eval;
/**
* The current health status
*
* @see GemFireHealth#OKAY_HEALTH
*/
private GemFireHealth.Health currentStatus;
private final Thread t;
private volatile boolean stopRequested = false;
private static int idCtr = 0;
/********** Constructors *********/
/**
* Creates a health monitor given its owner, configuration, and its dm
*/
public HealthMonitorImpl(InternalDistributedMember owner, GemFireHealthConfig config,
DistributionManager dm) {
this.owner = owner;
this.id = getNewId();
this.dm = dm;
this.eval = new GemFireHealthEvaluator(config, dm);
this.currentStatus = GemFireHealth.GOOD_HEALTH;
ThreadGroup tg = LoggingThreadGroup.createThreadGroup("HealthMonitor Threads", logger);
this.t = new Thread(tg, this,
LocalizedStrings.HealthMonitorImpl_HEALTH_MONITOR_OWNED_BY_0.toLocalizedString(owner));
this.t.setDaemon(true);
}
/************** HealthMonitor interface implementation ******************/
public int getId() {
return this.id;
}
public void resetStatus() {
this.currentStatus = GemFireHealth.GOOD_HEALTH;
this.eval.reset();
}
public String[] getDiagnosis(GemFireHealth.Health healthCode) {
return this.eval.getDiagnosis(healthCode);
}
public void stop() {
if (this.t.isAlive()) {
this.stopRequested = true;
this.t.interrupt();
}
}
/********** HealthMonitorImpl public methods **********/
/**
* Starts the monitor so that it will periodically do health checks.
*/
public void start() {
if (this.stopRequested) {
throw new RuntimeException(
LocalizedStrings.HealthMonitorImpl_A_HEALTH_MONITOR_CAN_NOT_BE_STARTED_ONCE_IT_HAS_BEEN_STOPPED
.toLocalizedString());
}
if (this.t.isAlive()) {
// it is already running
return;
}
this.t.start();
}
/********** Runnable interface implementation **********/
public void run() {
final int sleepTime = this.eval.getEvaluationInterval() * 1000;
if (logger.isDebugEnabled()) {
logger.debug("Starting health monitor. Health will be evaluated every {} seconds.",
(sleepTime / 1000));
}
try {
while (!this.stopRequested) {
// SystemFailure.checkFailure(); dm's stopper will do this
this.dm.getCancelCriterion().checkCancelInProgress(null);
Thread.sleep(sleepTime);
if (!this.stopRequested) {
GemFireHealth.Health newStatus = this.eval.evaluate();
if (newStatus != this.currentStatus) {
this.currentStatus = newStatus;
HealthListenerMessage msg = HealthListenerMessage.create(getId(), newStatus);
msg.setRecipient(this.owner);
this.dm.putOutgoing(msg);
}
}
}
} catch (InterruptedException ex) {
// No need to reset interrupt bit, we're exiting.
if (!this.stopRequested) {
logger.warn(LocalizedMessage
.create(LocalizedStrings.HealthMonitorImpl_UNEXPECTED_STOP_OF_HEALTH_MONITOR), ex);
}
} finally {
this.eval.close();
this.stopRequested = true;
if (logger.isDebugEnabled()) {
logger.debug("Stopping health monitor");
}
}
}
/********** Internal implementation **********/
private static synchronized int getNewId() {
idCtr += 1;
return idCtr;
}
}