com.hazelcast.quorum.impl.ProbabilisticQuorumFunction Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2018, 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.quorum.impl;
import com.hazelcast.core.Member;
import com.hazelcast.core.MembershipEvent;
import com.hazelcast.core.MembershipListener;
import com.hazelcast.internal.cluster.fd.PhiAccrualClusterFailureDetector;
import com.hazelcast.quorum.HeartbeatAware;
import com.hazelcast.quorum.QuorumFunction;
import com.hazelcast.util.Clock;
import java.util.Collection;
public class ProbabilisticQuorumFunction extends AbstractPingAwareQuorumFunction
implements HeartbeatAware, QuorumFunction, MembershipListener {
private final double suspicionThreshold;
private final int quorumSize;
private final int maxSampleSize;
private final long minStdDeviationMillis;
private final long acceptableHeartbeatPauseMillis;
private final long heartbeatIntervalMillis;
private final PhiAccrualClusterFailureDetector failureDetector;
public ProbabilisticQuorumFunction(int quorumSize, long heartbeatIntervalMillis,
long acceptableHeartbeatPauseMillis,
int maxSampleSize,
long minStdDeviationMillis,
double suspicionThreshold) {
this.heartbeatIntervalMillis = heartbeatIntervalMillis;
this.acceptableHeartbeatPauseMillis = acceptableHeartbeatPauseMillis;
this.maxSampleSize = maxSampleSize;
this.minStdDeviationMillis = minStdDeviationMillis;
this.suspicionThreshold = suspicionThreshold;
this.quorumSize = quorumSize;
this.failureDetector = new PhiAccrualClusterFailureDetector(acceptableHeartbeatPauseMillis,
heartbeatIntervalMillis, suspicionThreshold, maxSampleSize, minStdDeviationMillis);
}
@Override
public boolean apply(Collection members) {
if (members.size() < quorumSize) {
return false;
}
int count = 0;
long timestamp = Clock.currentTimeMillis();
for (Member member : members) {
if (!isAlivePerIcmp(member)) {
continue;
}
if (member.localMember() || failureDetector.isAlive(member, timestamp)) {
count++;
}
}
return count >= quorumSize;
}
@Override
public void memberRemoved(MembershipEvent membershipEvent) {
super.memberRemoved(membershipEvent);
failureDetector.remove(membershipEvent.getMember());
}
@Override
public void onHeartbeat(Member member, long timestamp) {
failureDetector.heartbeat(member, timestamp);
}
public double getSuspicionThreshold() {
return suspicionThreshold;
}
public int getMaxSampleSize() {
return maxSampleSize;
}
public long getMinStdDeviationMillis() {
return minStdDeviationMillis;
}
public long getAcceptableHeartbeatPauseMillis() {
return acceptableHeartbeatPauseMillis;
}
public long getHeartbeatIntervalMillis() {
return heartbeatIntervalMillis;
}
@SuppressWarnings("checkstyle:npathcomplexity")
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
ProbabilisticQuorumFunction that = (ProbabilisticQuorumFunction) o;
if (Double.compare(that.suspicionThreshold, suspicionThreshold) != 0) {
return false;
}
if (quorumSize != that.quorumSize) {
return false;
}
if (maxSampleSize != that.maxSampleSize) {
return false;
}
if (minStdDeviationMillis != that.minStdDeviationMillis) {
return false;
}
if (acceptableHeartbeatPauseMillis != that.acceptableHeartbeatPauseMillis) {
return false;
}
return heartbeatIntervalMillis == that.heartbeatIntervalMillis;
}
@Override
public int hashCode() {
int result;
long temp;
temp = Double.doubleToLongBits(suspicionThreshold);
result = (int) (temp ^ (temp >>> 32));
result = 31 * result + quorumSize;
result = 31 * result + maxSampleSize;
result = 31 * result + (int) (minStdDeviationMillis ^ (minStdDeviationMillis >>> 32));
result = 31 * result + (int) (acceptableHeartbeatPauseMillis ^ (acceptableHeartbeatPauseMillis >>> 32));
result = 31 * result + (int) (heartbeatIntervalMillis ^ (heartbeatIntervalMillis >>> 32));
return result;
}
}