alluxio.worker.SessionCleaner Maven / Gradle / Ivy
/*
* The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
* (the "License"). You may not use this work except in compliance with the License, which is
* available at www.apache.org/licenses/LICENSE-2.0
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
* either express or implied, as more fully set forth in the License.
*
* See the NOTICE file distributed with this work for information regarding copyright ownership.
*/
package alluxio.worker;
import alluxio.Sessions;
import alluxio.conf.Configuration;
import alluxio.conf.PropertyKey;
import alluxio.util.CommonUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.Closeable;
import java.util.ArrayList;
import java.util.List;
import javax.annotation.concurrent.NotThreadSafe;
/**
* SessionCleaner periodically checks if any session have become zombies, removes the zombie session
* and associated data when necessary. The syncing parameters (intervals) adopt directly from
* worker-to-master heartbeat configurations.
*/
@NotThreadSafe
public final class SessionCleaner implements Runnable, Closeable {
private static final Logger LOG = LoggerFactory.getLogger(SessionCleaner.class);
/** The object which supports cleaning up sessions. */
private final Sessions mSessions;
/** Milliseconds between each check. */
private final int mCheckIntervalMs;
private final List mSessionCleanables = new ArrayList<>();
/** Flag to indicate if the checking should continue. */
private volatile boolean mRunning;
/**
* Creates a new instance of {@link SessionCleaner}.
* @param sessions the worker's sessions will be clean up by callback if which has been timeout
* @param sessionCleanable who wants to cleanup the session
*/
public SessionCleaner(Sessions sessions, SessionCleanable... sessionCleanable) {
mSessions = sessions;
for (SessionCleanable sc : sessionCleanable) {
mSessionCleanables.add(sc);
}
mCheckIntervalMs = (int) Configuration
.getMs(PropertyKey.WORKER_BLOCK_HEARTBEAT_INTERVAL_MS);
mRunning = true;
}
/**
* Main loop for the cleanup, continuously looks for zombie sessions.
*/
@Override
public void run() {
long lastCheckMs = System.currentTimeMillis();
while (mRunning) {
// Check the time since last check, and wait until it is within check interval
long lastIntervalMs = System.currentTimeMillis() - lastCheckMs;
long toSleepMs = mCheckIntervalMs - lastIntervalMs;
if (toSleepMs > 0) {
CommonUtils.sleepMs(null, toSleepMs);
if (Thread.interrupted()) {
break;
}
} else {
LOG.warn("Session cleanup took: {}, expected: {}", lastIntervalMs, mCheckIntervalMs);
}
// Check if any sessions have become zombies, if so clean them up
lastCheckMs = System.currentTimeMillis();
for (long session : mSessions.getTimedOutSessions()) {
mSessions.removeSession(session);
for (SessionCleanable sc : mSessionCleanables) {
sc.cleanupSession(session);
}
}
}
}
/**
* Stops the checking, once this method is called, the object should be discarded.
*/
@Override
public void close() {
mRunning = false;
}
}