Java MemoryPoolMXBean.setUsageThreshold方法代碼示例

import java.lang.management.MemoryPoolMXBean; //導入方法依賴的package包/類
public static void initCodeSizeLimits(int nMaxSizeMemPoolCodeCache, int nMaxSizeMemPoolPermGen)
{
	// PJD remove ibm JMV
	List<MemoryPoolMXBean> pools = ManagementFactory.getMemoryPoolMXBeans();
	for (MemoryPoolMXBean p: pools)
	{
		if(p.getType().compareTo(MemoryType.NON_HEAP) == 0)
		{
			String cs = p.getName();
			if(cs.equalsIgnoreCase("Code Cache"))
				p.setUsageThreshold((long)nMaxSizeMemPoolCodeCache * 1024L * 1024L);
			else if(cs.equalsIgnoreCase("Perm Gen"))
				p.setUsageThreshold((long)nMaxSizeMemPoolPermGen * 1024L * 1024L);
		}
	}
}
 

import java.lang.management.MemoryPoolMXBean; //導入方法依賴的package包/類
private void setMemThreshold()
{
	m_bMaxPermanentHeap_MoSet = false;

	List<MemoryPoolMXBean> pools = ManagementFactory.getMemoryPoolMXBeans();
	for (MemoryPoolMXBean p: pools)
	{
		if(p.getType().compareTo(MemoryType.HEAP) == 0)
		{
			String cs = p.getName();
			if(cs.equalsIgnoreCase("Tenured gen"))
			{
				long l = 1024L * 1024L * (long)m_nMaxPermanentHeap_Mo;
				p.setUsageThreshold(l);
				m_tenuredPool = p;
			}				
		}
	}
}
 

import java.lang.management.MemoryPoolMXBean; //導入方法依賴的package包/類
protected void runTest() {
    long headerSize = CodeCacheUtils.getHeaderSize(btype);
    long allocationUnit = Math.max(0, CodeCacheUtils.MIN_ALLOCATION - headerSize);
    MemoryPoolMXBean bean = btype.getMemoryPool();
    long initialCount = bean.getUsageThresholdCount();
    long initialSize = bean.getUsage().getUsed();
    bean.setUsageThreshold(initialSize + THRESHOLD_STEP);
    for (int i = 0; i < ALLOCATION_STEP - 1; i++) {
        CodeCacheUtils.WB.allocateCodeBlob(allocationUnit, btype.id);
    }
    // Usage threshold check is triggered by GC cycle, so, call it
    CodeCacheUtils.WB.fullGC();
    checkUsageThresholdCount(bean, initialCount);
    long filledSize = bean.getUsage().getUsed();
    bean.setUsageThreshold(filledSize + THRESHOLD_STEP);
    for (int i = 0; i < ALLOCATION_STEP - 1; i++) {
        CodeCacheUtils.WB.allocateCodeBlob(allocationUnit, btype.id);
    }
    CodeCacheUtils.WB.fullGC();
    checkUsageThresholdCount(bean, initialCount);
    System.out.println("INFO: Case finished successfully for " + bean.getName());
}
 

import java.lang.management.MemoryPoolMXBean; //導入方法依賴的package包/類
protected void runTest() {
    MemoryPoolMXBean bean = btype.getMemoryPool();
    long initialThresholdCount = bean.getUsageThresholdCount();
    long initialUsage = bean.getUsage().getUsed();

    bean.setUsageThreshold(initialUsage + 1 + CodeCacheUtils.MIN_ALLOCATION);
    long size = CodeCacheUtils.getHeaderSize(btype);

    CodeCacheUtils.WB.allocateCodeBlob(Math.max(0, CodeCacheUtils.MIN_ALLOCATION
            - size), btype.id);
    // a gc cycle triggers usage threshold recalculation
    CodeCacheUtils.WB.fullGC();
    CodeCacheUtils.assertEQorGTE(btype, bean.getUsageThresholdCount(), initialThresholdCount,
            String.format("Usage threshold was hit: %d times for %s. "
                    + "Threshold value: %d with current usage: %d",
                    bean.getUsageThresholdCount(), bean.getName(),
                    bean.getUsageThreshold(), bean.getUsage().getUsed()));
    System.out.println("INFO: Case finished successfully for " + bean.getName());
}
 

import java.lang.management.MemoryPoolMXBean; //導入方法依賴的package包/類
public static void main(String[] args) {
    List<MemoryPoolMXBean> pools = ManagementFactory.getMemoryPoolMXBeans();
    boolean verified = false;
    for (MemoryPoolMXBean i : pools) {
        if ((i.getUsage().getMax() >= TWO_G)
                && i.isUsageThresholdSupported()) {
            i.setUsageThreshold(TWO_G);
            if(i.getUsageThreshold() != TWO_G)
                throw new RuntimeException("Usage threshold for"
                        + " pool '" + i.getName() + "' is " + i.getUsageThreshold()
                        + " and not equal to 2GB");
            verified = true;
        }
    }
    System.out.println("Ability to use big heap thresholds has "
            + (verified ? "" : "NOT ") + "been verified");
}
 

import java.lang.management.MemoryPoolMXBean; //導入方法依賴的package包/類
public static final void hitUsageThreshold(MemoryPoolMXBean bean,
        BlobType btype) {
    long initialSize = bean.getUsage().getUsed();
    bean.setUsageThreshold(initialSize + 1);
    long usageThresholdCount = bean.getUsageThresholdCount();
    long addr = WB.allocateCodeBlob(1, btype.id);
    WB.fullGC();
    Utils.waitForCondition(()
            -> bean.getUsageThresholdCount() == usageThresholdCount + 1);
    WB.freeCodeBlob(addr);
}
 

import java.lang.management.MemoryPoolMXBean; //導入方法依賴的package包/類
protected void runTest() {
    MemoryPoolMXBean bean = btype.getMemoryPool();
    ((NotificationEmitter) ManagementFactory.getMemoryMXBean()).
            addNotificationListener(this, null, null);
    bean.setUsageThreshold(bean.getUsage().getUsed() + 1);
    long beginTimestamp = System.currentTimeMillis();
    CodeCacheUtils.WB.allocateCodeBlob(
            CodeCacheUtils.ALLOCATION_SIZE, btype.id);
    CodeCacheUtils.WB.fullGC();
    /* waiting for expected event to be received plus double the time took
     to receive expected event(for possible unexpected) and
     plus 1 second in case expected event received (almost)immediately */
    Utils.waitForCondition(() -> {
        long currentTimestamp = System.currentTimeMillis();
        int eventsCount
                = counters.get(btype.getMemoryPool().getName()).get();
        if (eventsCount > 0) {
            if (eventsCount > 1) {
                return true;
            }
            long timeLastEventTook
                    = beginTimestamp - lastEventTimestamp;
            long timeoutValue
                    = 1000L + beginTimestamp + 3L * timeLastEventTook;
            return currentTimestamp > timeoutValue;
        }
        return false;
    });
    for (BlobType bt : BlobType.getAvailable()) {
        int expectedNotificationsAmount = bt.equals(btype) ? 1 : 0;
        CodeCacheUtils.assertEQorGTE(btype, counters.get(bt.getMemoryPool().getName()).get(),
                expectedNotificationsAmount, String.format("Unexpected "
                        + "amount of notifications for pool: %s",
                        bt.getMemoryPool().getName()));
    }
    try {
        ((NotificationEmitter) ManagementFactory.getMemoryMXBean()).
                removeNotificationListener(this);
    } catch (ListenerNotFoundException ex) {
        throw new AssertionError("Can't remove notification listener", ex);
    }
    System.out.printf("INFO: Scenario with %s finished%n", bean.getName());
}