weblogic.t3.srvr

Class CoreHealthService.ThreadMonitoringTimer

java.lang.Object

weblogic.t3.srvr.CoreHealthService.ThreadMonitoringTimer

All Implemented Interfaces:

weblogic.timers.TimerListener

Enclosing class:

CoreHealthService

private static final class CoreHealthService.ThreadMonitoringTimer
extends java.lang.Object
implements weblogic.timers.TimerListener

ThreadMonitoringTimer runs periodically and checks for stuck threads. Threads in the Execute Queues and the self-tuning implementation are checked.

Excluded in public API Reference.

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	alreadyDeadlocked
private ServerRuntimeMBean	serverRuntimeMBean
private long	stuckThreadMaxTime
private long	timerInterval

Constructor Summary

Constructors

Modifier	Constructor and Description
private	ThreadMonitoringTimer(long stuckThreadMaxTime, long stuckThreadsTimerInterval, ServerRuntimeMBean serverRuntimeMBean)

Method Summary

Modifier and Type	Method and Description
private void	checkDeadlockedThreads() Check for deadlocked threads and report them.
private void	checkStuckThreads() Called by the thread monitoring timer to check for stuck threads in all thread pools.
private boolean	logStuckThreadMessage(long elapsedTime, long maxTime) Determine if logging should be done for a stuck thread.
private boolean	logStuckThreads(ExecuteThread[] stuckThreads, int totalCount, java.lang.String queueName) This method logs stuck threads.
void	timerExpired(weblogic.timers.Timer timer) This method is invoked by a TimerManager when a timer expires.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

stuckThreadMaxTime

private final long stuckThreadMaxTime

timerInterval

private final long timerInterval

serverRuntimeMBean

private final ServerRuntimeMBean serverRuntimeMBean

alreadyDeadlocked

private boolean alreadyDeadlocked

Constructor Detail

ThreadMonitoringTimer

private ThreadMonitoringTimer(long stuckThreadMaxTime,
                              long stuckThreadsTimerInterval,
                              ServerRuntimeMBean serverRuntimeMBean)

Method Detail

timerExpired

public void timerExpired(weblogic.timers.Timer timer)

Description copied from interface: weblogic.timers.TimerListener

This method is invoked by a TimerManager when a timer expires.

Specified by:

timerExpired in interface weblogic.timers.TimerListener

Parameters:

timer - The timer that expired and caused the listener to be invoked.

checkDeadlockedThreads

private void checkDeadlockedThreads()

Check for deadlocked threads and report them.

checkStuckThreads

private void checkStuckThreads()

Called by the thread monitoring timer to check for stuck threads in all thread pools. User configured actions are taken when stuck threads are encountered. The actions include shutting down WorkManager, the entire server or get the app into admin mode.

Note that stuck thread actions are possible only for self-tuning pool and NOT for execute queues.

logStuckThreads

private boolean logStuckThreads(ExecuteThread[] stuckThreads,
                                int totalCount,
                                java.lang.String queueName)

This method logs stuck threads. Care is taken to avoid frequent logging of the same stuck thread. We log a couple of times and stop.

Returns:

true if all the threads are stuck, false otherwise.

logStuckThreadMessage

private boolean logStuckThreadMessage(long elapsedTime,
                                      long maxTime)

Determine if logging should be done for a stuck thread. This method prevents flooding the logs with stuck thread messages if a thread is stuck forever due to a deadlock.