org.apache.jackrabbit.oak.plugins.index.importer.ClusterNodeStoreLock Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* distributed with this work for additional information
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* 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
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package org.apache.jackrabbit.oak.plugins.index.importer;
import java.util.concurrent.Callable;
import java.util.concurrent.TimeUnit;
import org.apache.jackrabbit.oak.api.CommitFailedException;
import org.apache.jackrabbit.oak.plugins.index.AsyncIndexUpdate;
import org.apache.jackrabbit.oak.spi.state.NodeBuilder;
import org.apache.jackrabbit.oak.spi.state.NodeState;
import org.apache.jackrabbit.oak.spi.state.NodeStore;
import org.apache.jackrabbit.oak.stats.Clock;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Lock implementation for clustered scenario. The locking is done
* by setting the lease time for the lane to distant future which
* prevent AsyncIndexUpdate from running.
*/
public class ClusterNodeStoreLock implements AsyncIndexerLock {
/**
* Use a looong lease time to ensure that async indexer does not start
* in between the import process which can take some time
*/
private static final long LOCK_TIMEOUT = TimeUnit.DAYS.toMillis(100);
// retry for at most 2 minutes
private static final long MAX_RETRY_TIME = 2 * 60 * 1000;
private final Logger log = LoggerFactory.getLogger(getClass());
private final NodeStore nodeStore;
private final Clock clock;
public ClusterNodeStoreLock(NodeStore nodeStore){
this(nodeStore, Clock.SIMPLE);
}
public ClusterNodeStoreLock(NodeStore nodeStore, Clock clock) {
this.nodeStore = nodeStore;
this.clock = clock;
}
@Override
public ClusteredLockToken lock(String asyncIndexerLane) throws CommitFailedException {
return retryIfNeeded(() -> tryLock(asyncIndexerLane));
}
private ClusteredLockToken tryLock(String asyncIndexerLane) throws CommitFailedException {
NodeBuilder builder = nodeStore.getRoot().builder();
NodeBuilder async = builder.child(":async");
String leaseName = AsyncIndexUpdate.leasify(asyncIndexerLane);
long leaseEndTime = clock.getTime() + LOCK_TIMEOUT;
if (async.hasProperty(leaseName)){
log.info("AsyncIndexer found to be running currently. Lease update would cause its" +
"commit to fail. Such a failure should be ignored");
}
async.setProperty(leaseName, leaseEndTime);
async.setProperty(lockName(asyncIndexerLane), true);
NodeStoreUtils.mergeWithConcurrentCheck(nodeStore, builder);
log.info("Acquired the lock for async indexer lane [{}]", asyncIndexerLane);
return new ClusteredLockToken(asyncIndexerLane, leaseEndTime);
}
private T retryIfNeeded(Callable r) throws CommitFailedException {
// Attempt few times if merge failure due to current running indexer cycle
int backOffMaxMillis = 1;
long start = System.currentTimeMillis();
while (true) {
try {
return r.call();
} catch (Exception e) {
log.info("Commit failed, retrying: " + e);
long time = System.currentTimeMillis() - start;
if (time > MAX_RETRY_TIME) {
if (e instanceof CommitFailedException) {
throw (CommitFailedException) e;
}
log.error("Unexpected failure retrying", e);
throw new CommitFailedException(CommitFailedException.UNSUPPORTED, 2, e.getMessage(), e);
}
int sleep = (int) (backOffMaxMillis * Math.random());
backOffMaxMillis *= 2;
log.info("Wait " + sleep + " ms");
try {
Thread.sleep(sleep);
} catch (InterruptedException e1) {
// ignore
}
}
}
}
@Override
public void unlock(ClusteredLockToken token) throws CommitFailedException {
retryIfNeeded(() -> tryUnlock(token));
}
private Void tryUnlock(ClusteredLockToken token) throws CommitFailedException {
String leaseName = AsyncIndexUpdate.leasify(token.laneName);
NodeBuilder builder = nodeStore.getRoot().builder();
NodeBuilder async = builder.child(":async");
async.removeProperty(leaseName);
async.removeProperty(lockName(token.laneName));
NodeStoreUtils.mergeWithConcurrentCheck(nodeStore, builder);
log.info("Remove the lock for async indexer lane [{}]", token.laneName);
return null;
}
public boolean isLocked(String asyncIndexerLane) {
NodeState async = nodeStore.getRoot().getChildNode(":async");
String leaseName = lockName(asyncIndexerLane);
return async.hasProperty(leaseName);
}
private static String lockName(String asyncIndexerLane) {
return asyncIndexerLane + "-lock";
}
}
class ClusteredLockToken implements AsyncIndexerLock.LockToken {
final String laneName;
final long timeout;
ClusteredLockToken(String laneName, long timeout) {
this.laneName = laneName;
this.timeout = timeout;
}
}