/*
* The MIT License
*
* Copyright (c) 2004-2009, Sun Microsystems, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package hudson.slaves;
import hudson.model.AsyncPeriodicWork;
import hudson.model.TaskListener;
import jenkins.model.Jenkins;
import hudson.model.Computer;
import hudson.util.TimeUnit2;
import hudson.remoting.VirtualChannel;
import hudson.remoting.Channel;
import hudson.remoting.Callable;
import hudson.Extension;
import java.io.IOException;
import java.util.logging.Logger;
/**
* Makes sure that connections to slaves are alive, and if they are not, cut them off.
*
* <p>
* If we only rely on TCP retransmission time out for this, the time it takes to detect a bad connection
* is in the order of 10s of minutes, so we take the matters to our own hands.
*
* @author Kohsuke Kawaguchi
* @since 1.325
*/
@Extension
public class ConnectionActivityMonitor extends AsyncPeriodicWork {
public ConnectionActivityMonitor() {
super("Connection Activity monitoring to slaves");
}
protected void execute(TaskListener listener) throws IOException, InterruptedException {
if (!enabled) return;
long now = System.currentTimeMillis();
for (Computer c: Jenkins.getInstance().getComputers()) {
VirtualChannel ch = c.getChannel();
if (ch instanceof Channel) {
Channel channel = (Channel) ch;
if (now-channel.getLastHeard() > TIME_TILL_PING) {
// haven't heard from this slave for a while.
Long lastPing = (Long)channel.getProperty(ConnectionActivityMonitor.class);
if (lastPing!=null && now-lastPing > TIMEOUT) {
LOGGER.info("Repeated ping attempts failed on "+c.getName()+". Disconnecting");
c.disconnect(OfflineCause.create(Messages._ConnectionActivityMonitor_OfflineCause()));
} else {
// send a ping. if we receive a reply, it will be reflected in the next getLastHeard() call.
channel.callAsync(PING_COMMAND);
if (lastPing==null)
channel.setProperty(ConnectionActivityMonitor.class,now);
}
} else {
// we are receiving data nicely
channel.setProperty(ConnectionActivityMonitor.class,null);
}
}
}
}
public long getRecurrencePeriod() {
return enabled ? FREQUENCY : TimeUnit2.DAYS.toMillis(30);
}
/**
* Time till initial ping
*/
private static final long TIME_TILL_PING = Long.getLong(ConnectionActivityMonitor.class.getName()+".timeToPing",TimeUnit2.MINUTES.toMillis(3));
private static final long FREQUENCY = Long.getLong(ConnectionActivityMonitor.class.getName()+".frequency",TimeUnit2.SECONDS.toMillis(10));
/**
* When do we abandon the effort and cut off?
*/
private static final long TIMEOUT = Long.getLong(ConnectionActivityMonitor.class.getName()+".timeToPing",TimeUnit2.MINUTES.toMillis(4));
// disabled by default until proven in the production
public boolean enabled = Boolean.getBoolean(ConnectionActivityMonitor.class.getName()+".enabled");
private static final PingCommand PING_COMMAND = new PingCommand();
private static final class PingCommand implements Callable<Void,RuntimeException> {
public Void call() throws RuntimeException {
return null;
}
private static final long serialVersionUID = 1L;
}
private static final Logger LOGGER = Logger.getLogger(ConnectionActivityMonitor.class.getName());
}