Java Code Examples for java.lang.management.MemoryPoolMXBean#setCollectionUsageThreshold()

private void registerForNotifications() {
  // Register the listener with MemoryMXBean
  NotificationEmitter emitter = (NotificationEmitter) ManagementFactory.getMemoryMXBean();
  emitter.addNotificationListener(listener, null, null);

  // set collection usage threshold.
  for (MemoryPoolMXBean pool : ManagementFactory.getMemoryPoolMXBeans()) {
    if (pool.getType() == MemoryType.HEAP &&
      pool.isUsageThresholdSupported() &&
      pool.isCollectionUsageThresholdSupported()) {

      long threshold = (pool.getUsage().getMax() * thresholdPercentage) / 100;
      logger.info("setting collection threshold for " + pool.getName() +
        " with max " + pool.getUsage().getMax() +
        " to " + threshold);

      pool.setCollectionUsageThreshold(threshold);
      monitoredPools.put(pool.getName(), pool.getCollectionUsageThresholdCount());
    } else {
      logger.info("skip monitoring for pool " + pool.getName());
    }
  }
}
 

/**
 * Register with the JVM to get threshold events.
 * 
 * Package private for testing.
 */
void startJVMThresholdListener() {
  final MemoryPoolMXBean memoryPoolMXBean = getTenuredMemoryPoolMXBean();

  // Set collection threshold to a low value, so that we can get
  // notifications after every GC run. After each such collection
  // threshold notification we set the usage thresholds to an
  // appropriate value.
  if (!testDisableMemoryUpdates) {
    memoryPoolMXBean.setCollectionUsageThreshold(1);
    // also set for notifications from survivor space GC
    final MemoryPoolMXBean survivorPoolMXBean = getSurvivorPoolMXBean();
    if (survivorPoolMXBean != null
        && survivorPoolMXBean.isCollectionUsageThresholdSupported()) {
      survivorPoolMXBean.setCollectionUsageThreshold(1);
    }
  }
  
  final long usageThreshold = memoryPoolMXBean.getUsageThreshold();
  this.cache.getLoggerI18n().info(
      LocalizedStrings.HeapMemoryMonitor_OVERRIDDING_MEMORYPOOLMXBEAN_HEAP_0_NAME_1,
      new Object[] { Long.valueOf(usageThreshold), memoryPoolMXBean.getName() });

  MemoryMXBean mbean = ManagementFactory.getMemoryMXBean();
  NotificationEmitter emitter = (NotificationEmitter) mbean;
  emitter.addNotificationListener(this, null, null);
}
 

/**
 * Register with the JVM to get threshold events.
 * 
 * Package private for testing.
 */
void startJVMThresholdListener() {
  final MemoryPoolMXBean memoryPoolMXBean = getTenuredMemoryPoolMXBean();

  // Set collection threshold to a low value, so that we can get
  // notifications after every GC run. After each such collection
  // threshold notification we set the usage thresholds to an
  // appropriate value.
  if (!testDisableMemoryUpdates) {
    memoryPoolMXBean.setCollectionUsageThreshold(1);
    // also set for notifications from survivor space GC
    final MemoryPoolMXBean survivorPoolMXBean = getSurvivorPoolMXBean();
    if (survivorPoolMXBean != null
        && survivorPoolMXBean.isCollectionUsageThresholdSupported()) {
      survivorPoolMXBean.setCollectionUsageThreshold(1);
    }
  }
  
  final long usageThreshold = memoryPoolMXBean.getUsageThreshold();
  this.cache.getLoggerI18n().info(
      LocalizedStrings.HeapMemoryMonitor_OVERRIDDING_MEMORYPOOLMXBEAN_HEAP_0_NAME_1,
      new Object[] { Long.valueOf(usageThreshold), memoryPoolMXBean.getName() });

  MemoryMXBean mbean = ManagementFactory.getMemoryMXBean();
  NotificationEmitter emitter = (NotificationEmitter) mbean;
  emitter.addNotificationListener(this, null, null);
}
 

public void enableOptionalFunctionality()  {
    try {
        // ClassLoadingMXBean operations
        classBean.setVerbose(true);

        // MemoryMXBean operations
        memBean.setVerbose(true);

        // MemoryPoolMXBean operations
        for (MemoryPoolMXBean memPoolBean: memPoolBeans) {
            memPoolBean.resetPeakUsage();

            if (memPoolBean.isCollectionUsageThresholdSupported()) {
                memPoolBean.setCollectionUsageThreshold(10000);
            }

            if (memPoolBean.isUsageThresholdSupported()) {
                memPoolBean.setUsageThreshold(200000);
            }            
        }

        // ThreadMXBean operations
        threadBean.resetPeakThreadCount();

        if (threadBean.isThreadContentionMonitoringSupported()) {
            threadBean.setThreadContentionMonitoringEnabled(true);
        }

        if (threadBean.isThreadCpuTimeSupported()) {
            threadBean.setThreadCpuTimeEnabled(true);
        }
        
        // LoggingMXBean operations
        List<String> loggers = logBean.getLoggerNames();
        
        String[] levels = {"SEVERE", "WARNING", "INFO", "CONFIG", "FINE", "FINER", "FINEST"};
        int i = 0;
        
        for( String logger : loggers) {               	
            if (i > 6) {
            	i = i - 7;
            }
            
            // There's a chance the logger no longer exists
            String parent = logBean.getParentLoggerName(logger);
            if (parent != null) {
            	logBean.setLoggerLevel(logger, levels[i]);
            }
            
            i++;                
        }
        
    } catch (UnsupportedOperationException uoe) {
        Message.logOut("One of the operations you tried is not supported");
        uoe.printStackTrace();
    }
}
 

private SpillableMemoryManager() {
    ((NotificationEmitter)ManagementFactory.getMemoryMXBean()).addNotificationListener(this, null, null);
    List<MemoryPoolMXBean> mpbeans = ManagementFactory.getMemoryPoolMXBeans();
    MemoryPoolMXBean tenuredHeap = null;
    long tenuredHeapSize = 0;
    long totalSize = 0;
    for (MemoryPoolMXBean pool : mpbeans) {
        log.debug("Found heap (" + pool.getName() + ") of type " + pool.getType());
        if (pool.getType() == MemoryType.HEAP) {
            long size = pool.getUsage().getMax();
            totalSize += size;
            // CMS Old Gen or "tenured" is the only heap that supports
            // setting usage threshold.
            if (pool.isUsageThresholdSupported()) {
                tenuredHeapSize = size;
                tenuredHeap = pool;
            }
        }
    }
    extraGCSpillSizeThreshold  = (long) (totalSize * extraGCThresholdFraction);
    if (tenuredHeap == null) {
        throw new RuntimeException("Couldn't find heap");
    }
    log.debug("Selected heap to monitor (" +
        tenuredHeap.getName() + ")");

    // we want to set both collection and usage threshold alerts to be
    // safe. In some local tests after a point only collection threshold
    // notifications were being sent though usage threshold notifications
    // were sent early on. So using both would ensure that
    // 1) we get notified early (though usage threshold exceeded notifications)
    // 2) we get notified always when threshold is exceeded (either usage or
    //    collection)

    /* We set the threshold to be 50% of tenured since that is where
     * the GC starts to dominate CPU time according to Sun doc */
    tenuredHeap.setCollectionUsageThreshold((long)(tenuredHeapSize * collectionMemoryThresholdFraction));
    // we set a higher threshold for usage threshold exceeded notification
    // since this is more likely to be effective sooner and we do not
    // want to be spilling too soon
    tenuredHeap.setUsageThreshold((long)(tenuredHeapSize * memoryThresholdFraction));
}