/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at
* trunk/opends/resource/legal-notices/OpenDS.LICENSE
* or https://OpenDS.dev.java.net/OpenDS.LICENSE.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at
* trunk/opends/resource/legal-notices/OpenDS.LICENSE. If applicable,
* add the following below this CDDL HEADER, with the fields enclosed
* by brackets "[]" replaced with your own identifying information:
* Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*
*
* Copyright 2008-2009 Sun Microsystems, Inc.
* Portions Copyright 2011-2013 ForgeRock AS
*/
package org.opends.server.replication.server;
import static org.opends.server.loggers.debug.DebugLogger.debugEnabled;
import static org.opends.server.loggers.debug.DebugLogger.getTracer;
import org.opends.server.api.DirectoryThread;
import org.opends.server.loggers.debug.DebugTracer;
import org.opends.server.replication.common.ServerStatus;
import org.opends.server.replication.common.StatusMachineEvent;
import org.opends.server.types.DebugLogLevel;
/**
* This thread is in charge of periodically determining if the connected
* directory servers of the domain it is associated with are late or not
* regarding the changes they have to replay. A threshold is set for the maximum
* allowed number of pending changes. When the threshold for a DS is crossed,
* the status analyzer must make the DS status change to DEGRADED_STATUS. When
* the threshold is uncrossed, the status analyzer must make the DS status
* change back to NORMAL_STATUS. To have meaning of status, please refer to
* ServerStatus class.
*/
public class StatusAnalyzer extends DirectoryThread
{
private volatile boolean shutdown = false;
/**
* The tracer object for the debug logger.
*/
private static final DebugTracer TRACER = getTracer();
private final ReplicationServerDomain replicationServerDomain;
private volatile int degradedStatusThreshold = -1;
// Sleep time for the thread, in ms.
private static final int STATUS_ANALYZER_SLEEP_TIME = 5000;
private volatile boolean done = false;
private final Object shutdownLock = new Object();
/**
* Create a StatusAnalyzer.
* @param replicationServerDomain The ReplicationServerDomain the status
* analyzer is for.
* @param degradedStatusThreshold The pending changes threshold value to be
* used for putting a DS in DEGRADED_STATUS.
*/
public StatusAnalyzer(ReplicationServerDomain replicationServerDomain,
int degradedStatusThreshold)
{
super("Replication server RS("
+ replicationServerDomain.getReplicationServer()
.getServerId() + ") delay monitor for domain \""
+ replicationServerDomain.getBaseDn() + "\"");
this.replicationServerDomain = replicationServerDomain;
this.degradedStatusThreshold = degradedStatusThreshold;
}
/**
* Run method for the StatusAnalyzer.
* Analyzes if servers are late or not, and change their status accordingly.
*/
@Override
public void run()
{
if (debugEnabled())
{
TRACER.debugInfo("Directory server status analyzer starting for dn " +
replicationServerDomain.getBaseDn());
}
boolean interrupted = false;
while (!shutdown && !interrupted)
{
synchronized (shutdownLock)
{
if (!shutdown)
{
try
{
shutdownLock.wait(STATUS_ANALYZER_SLEEP_TIME);
}
catch (InterruptedException e)
{
// Server shutdown monitor may interrupt slow threads.
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
shutdown = true;
break;
}
}
}
// Go through each connected DS, get the number of pending changes we have
// for it and change status accordingly if threshold value is
// crossed/uncrossed
for (DataServerHandler serverHandler :
replicationServerDomain.getConnectedDSs(). values())
{
// Get number of pending changes for this server
int nChanges = serverHandler.getRcvMsgQueueSize();
if (debugEnabled())
{
TRACER.debugInfo("Status analyzer for dn " +
replicationServerDomain.getBaseDn() + " DS " +
Integer.toString(serverHandler.getServerId()) + " has " + nChanges +
" message(s) in writer queue. This is in RS " +
replicationServerDomain.getReplicationServer().getServerId());
}
// Check status to know if it is relevant to change the status. Do not
// take RSD lock to test. If we attempt to change the status whereas
// we are in a status that do not allows that, this will be noticed by
// the changeStatusFromStatusAnalyzer method. This allows to take the
// lock roughly only when needed versus every sleep time timeout.
if (degradedStatusThreshold > 0)
// Threshold value = 0 means no status analyzer (no degrading system)
// we should not have that as the status analyzer thread should not be
// created if this is the case, but for sanity purpose, we add this
// test
{
if (nChanges >= degradedStatusThreshold)
{
if (serverHandler.getStatus() == ServerStatus.NORMAL_STATUS)
{
interrupted =
replicationServerDomain.changeStatusFromStatusAnalyzer(
serverHandler,
StatusMachineEvent.TO_DEGRADED_STATUS_EVENT);
if (interrupted)
{
// Finish job and let thread die
TRACER.debugInfo("Status analyzer for dn " +
replicationServerDomain.getBaseDn() +
" has been interrupted and will die. This is in RS " +
replicationServerDomain.getReplicationServer().getServerId());
break;
}
}
} else
{
if (serverHandler.getStatus() == ServerStatus.DEGRADED_STATUS)
{
interrupted =
replicationServerDomain.changeStatusFromStatusAnalyzer(
serverHandler,
StatusMachineEvent.TO_NORMAL_STATUS_EVENT);
if (interrupted)
{
// Finish job and let thread die
TRACER.debugInfo("Status analyzer for dn " +
replicationServerDomain.getBaseDn() +
" has been interrupted and will die. This is in RS " +
replicationServerDomain.getReplicationServer().getServerId());
break;
}
}
}
}
}
}
done = true;
TRACER.debugInfo("Status analyzer for dn " +
replicationServerDomain.getBaseDn() + " is terminated." +
" This is in RS " +
replicationServerDomain.getReplicationServer().getServerId());
}
/**
* Stops the thread.
*/
public void shutdown()
{
synchronized (shutdownLock)
{
shutdown = true;
shutdownLock.notifyAll();
if (debugEnabled())
{
TRACER.debugInfo("Shutting down status analyzer for dn "
+ replicationServerDomain.getBaseDn() + " in RS "
+ replicationServerDomain.getReplicationServer().getServerId());
}
}
}
/**
* Waits for analyzer death. If not finished within 2 seconds,
* forces interruption
*/
public void waitForShutdown()
{
try
{
int FACTOR = 40; // Wait for 2 seconds before interrupting the thread
int n = 0;
while (!done && this.isAlive())
{
Thread.sleep(50);
n++;
if (n >= FACTOR)
{
TRACER.debugInfo("Interrupting status analyzer for dn " +
replicationServerDomain.getBaseDn() + " in RS " +
replicationServerDomain.getReplicationServer().getServerId());
this.interrupt();
}
}
} catch (InterruptedException e)
{
// exit the loop if this thread is interrupted.
}
}
/**
* Sets the threshold value.
* @param degradedStatusThreshold The new threshold value.
*/
public void setDegradedStatusThreshold(int degradedStatusThreshold)
{
if (debugEnabled())
{
TRACER.debugInfo("Directory server status analyzer for dn " +
replicationServerDomain.getBaseDn() + " changing threshold value to " +
degradedStatusThreshold);
}
this.degradedStatusThreshold = degradedStatusThreshold;
}
}