Examples with GarbageCollectionNotificationInfo com.sun.management.GarbageCollectionNotificationInfo used on opensource projects

Example 1 with GarbageCollectionNotificationInfo

use of com.sun.management.GarbageCollectionNotificationInfo in project jdk8u_jdk by JetBrains.

the class GarbageCollectionNotificationContentTest method main.

public static void main(String[] args) throws Exception {
    MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
    final Boolean isNotificationSupported = AccessController.doPrivileged(new PrivilegedAction<Boolean>() {

        public Boolean run() {
            try {
                Class cl = Class.forName("sun.management.VMManagementImpl");
                Field f = cl.getDeclaredField("gcNotificationSupport");
                f.setAccessible(true);
                return f.getBoolean(null);
            } catch (ClassNotFoundException e) {
                return false;
            } catch (NoSuchFieldException e) {
                return false;
            } catch (IllegalAccessException e) {
                return false;
            }
        }
    });
    if (!isNotificationSupported) {
        System.out.println("GC Notification not supported by the JVM, test skipped");
        return;
    }
    final ObjectName gcMXBeanPattern = new ObjectName("java.lang:type=GarbageCollector,*");
    Set<ObjectName> names = mbs.queryNames(gcMXBeanPattern, null);
    if (names.isEmpty())
        throw new Exception("Test incorrect: no GC MXBeans");
    number = names.size();
    for (ObjectName n : names) {
        if (mbs.isInstanceOf(n, "javax.management.NotificationEmitter")) {
            listenerInvoked.put(n.getCanonicalName(), null);
            GcListener listener = new GcListener();
            mbs.addNotificationListener(n, listener, null, null);
        }
    }
    // Invocation of System.gc() to trigger major GC
    System.gc();
    // Allocation of many short living and small objects to trigger minor GC
    Object[] data = new Object[32];
    for (int i = 0; i < 100000000; i++) {
        data[i % 32] = new int[8];
    }
    int wakeup = 0;
    synchronized (synchronizer) {
        while (count != number) {
            synchronizer.wait(10000);
            wakeup++;
            if (wakeup > 10)
                break;
        }
    }
    for (GarbageCollectionNotificationInfo notif : listenerInvoked.values()) {
        checkGarbageCollectionNotificationInfoContent(notif);
    }
    System.out.println("Test passed");
}

Example 2 with GarbageCollectionNotificationInfo

use of com.sun.management.GarbageCollectionNotificationInfo in project jdk8u_jdk by JetBrains.

the class GarbageCollectorImpl method createGCNotification.

void createGCNotification(long timestamp, String gcName, String gcAction, String gcCause, GcInfo gcInfo) {
    if (!hasListeners()) {
        return;
    }
    Notification notif = new Notification(GarbageCollectionNotificationInfo.GARBAGE_COLLECTION_NOTIFICATION, getObjectName(), getNextSeqNumber(), timestamp, gcName);
    GarbageCollectionNotificationInfo info = new GarbageCollectionNotificationInfo(gcName, gcAction, gcCause, gcInfo);
    CompositeData cd = GarbageCollectionNotifInfoCompositeData.toCompositeData(info);
    notif.setUserData(cd);
    sendNotification(notif);
}

Example 3 with GarbageCollectionNotificationInfo

use of com.sun.management.GarbageCollectionNotificationInfo in project cassandra by apache.

the class GCInspector method handleNotification.

public void handleNotification(final Notification notification, final Object handback) {
    String type = notification.getType();
    if (type.equals(GarbageCollectionNotificationInfo.GARBAGE_COLLECTION_NOTIFICATION)) {
        // retrieve the garbage collection notification information
        CompositeData cd = (CompositeData) notification.getUserData();
        GarbageCollectionNotificationInfo info = GarbageCollectionNotificationInfo.from(cd);
        String gcName = info.getGcName();
        GcInfo gcInfo = info.getGcInfo();
        long duration = gcInfo.getDuration();
        /*
             * The duration supplied in the notification info includes more than just
             * application stopped time for concurrent GCs. Try and do a better job coming up with a good stopped time
             * value by asking for and tracking cumulative time spent blocked in GC.
             */
        GCState gcState = gcStates.get(gcName);
        if (gcState.assumeGCIsPartiallyConcurrent) {
            long previousTotal = gcState.lastGcTotalDuration;
            long total = gcState.gcBean.getCollectionTime();
            gcState.lastGcTotalDuration = total;
            // may be zero for a really fast collection
            duration = total - previousTotal;
        }
        StringBuilder sb = new StringBuilder();
        sb.append(info.getGcName()).append(" GC in ").append(duration).append("ms.  ");
        long bytes = 0;
        Map<String, MemoryUsage> beforeMemoryUsage = gcInfo.getMemoryUsageBeforeGc();
        Map<String, MemoryUsage> afterMemoryUsage = gcInfo.getMemoryUsageAfterGc();
        for (String key : gcState.keys(info)) {
            MemoryUsage before = beforeMemoryUsage.get(key);
            MemoryUsage after = afterMemoryUsage.get(key);
            if (after != null && after.getUsed() != before.getUsed()) {
                sb.append(key).append(": ").append(before.getUsed());
                sb.append(" -> ");
                sb.append(after.getUsed());
                if (!key.equals(gcState.keys[gcState.keys.length - 1]))
                    sb.append("; ");
                bytes += before.getUsed() - after.getUsed();
            }
        }
        while (true) {
            State prev = state.get();
            if (state.compareAndSet(prev, new State(duration, bytes, prev)))
                break;
        }
        String st = sb.toString();
        if (GC_WARN_THRESHOLD_IN_MS != 0 && duration > GC_WARN_THRESHOLD_IN_MS)
            logger.warn(st);
        else if (duration > MIN_LOG_DURATION)
            logger.info(st);
        else if (logger.isTraceEnabled())
            logger.trace(st);
        if (duration > STAT_THRESHOLD)
            StatusLogger.log();
        // if we just finished an old gen collection and we're still using a lot of memory, try to reduce the pressure
        if (gcState.assumeGCIsOldGen)
            LifecycleTransaction.rescheduleFailedDeletions();
    }
}

Example 4 with GarbageCollectionNotificationInfo

use of com.sun.management.GarbageCollectionNotificationInfo in project bazel by bazelbuild.

the class RetainedHeapLimiter method handleNotification.

@Override
public void handleNotification(Notification notification, Object handback) {
    if (!notification.getType().equals(GarbageCollectionNotificationInfo.GARBAGE_COLLECTION_NOTIFICATION)) {
        return;
    }
    GarbageCollectionNotificationInfo info = GarbageCollectionNotificationInfo.from((CompositeData) notification.getUserData());
    Map<String, MemoryUsage> spaces = info.getGcInfo().getMemoryUsageAfterGc();
    for (Map.Entry<String, MemoryUsage> entry : spaces.entrySet()) {
        if (isTenuredSpace(entry.getKey())) {
            MemoryUsage space = entry.getValue();
            if (space.getMax() == 0) {
                // The CMS collector sometimes passes us nonsense stats.
                continue;
            }
            long percentUsed = 100 * space.getUsed() / space.getMax();
            if (percentUsed > occupiedHeapPercentageThreshold) {
                if (info.getGcCause().equals("System.gc()") && !throwingOom.getAndSet(true)) {
                    // Assume we got here from a GC initiated by the other branch.
                    String exitMsg = String.format("RetainedHeapLimiter forcing exit due to GC thrashing: tenured space " + "%s out of %s (>%s%%) occupied after back-to-back full GCs", space.getUsed(), space.getMax(), occupiedHeapPercentageThreshold);
                    System.err.println(exitMsg);
                    LOG.info(exitMsg);
                    // Exits the runtime.
                    BugReport.handleCrash(new OutOfMemoryError(exitMsg));
                } else if (System.currentTimeMillis() - lastTriggeredGcInMilliseconds > MIN_TIME_BETWEEN_TRIGGERED_GC_MILLISECONDS) {
                    LOG.info("Triggering a full GC with " + space.getUsed() + " out of " + space.getMax() + " used");
                    // Force a full stop-the-world GC and see if it can get us below the threshold.
                    System.gc();
                    lastTriggeredGcInMilliseconds = System.currentTimeMillis();
                }
            }
        }
    }
}