| /* |
| * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| // Stress the GC locker by calling GetPrimitiveArrayCritical while |
| // concurrently filling up old gen. |
| |
| import java.lang.management.MemoryPoolMXBean; |
| import java.lang.management.ManagementFactory; |
| import java.lang.management.MemoryUsage; |
| import java.nio.ByteBuffer; |
| import java.util.ArrayDeque; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Queue; |
| |
| final class ThreadUtils { |
| public static void sleep(long durationMS) { |
| try { |
| Thread.sleep(durationMS); |
| } catch (Exception e) { |
| } |
| } |
| } |
| |
| class Filler { |
| private static final int SIZE = 250000; |
| |
| private int[] i1 = new int[SIZE]; |
| private int[] i2 = new int[SIZE]; |
| private short[] s1 = new short[SIZE]; |
| private short[] s2 = new short[SIZE]; |
| |
| private Map<Object, Object> map = new HashMap<>(); |
| |
| public Filler() { |
| for (int i = 0; i < 10000; i++) { |
| map.put(new Object(), new Object()); |
| } |
| } |
| } |
| |
| class Exitable { |
| private volatile boolean shouldExit = false; |
| |
| protected boolean shouldExit() { |
| return shouldExit; |
| } |
| |
| public void exit() { |
| shouldExit = true; |
| } |
| } |
| |
| class MemoryWatcher { |
| private MemoryPoolMXBean bean; |
| private final int thresholdPromille = 750; |
| private final int criticalThresholdPromille = 800; |
| private final int minGCWaitMS = 1000; |
| private final int minFreeWaitElapsedMS = 30000; |
| private final int minFreeCriticalWaitMS = 500; |
| |
| private int lastUsage = 0; |
| private long lastGCDetected = System.currentTimeMillis(); |
| private long lastFree = System.currentTimeMillis(); |
| |
| public MemoryWatcher(String mxBeanName) { |
| List<MemoryPoolMXBean> memoryBeans = ManagementFactory.getMemoryPoolMXBeans(); |
| for (MemoryPoolMXBean bean : memoryBeans) { |
| if (bean.getName().equals(mxBeanName)) { |
| this.bean = bean; |
| break; |
| } |
| } |
| } |
| |
| private int getMemoryUsage() { |
| if (bean == null) { |
| Runtime r = Runtime.getRuntime(); |
| float free = (float) r.freeMemory() / r.maxMemory(); |
| return Math.round((1 - free) * 1000); |
| } else { |
| MemoryUsage usage = bean.getUsage(); |
| float used = (float) usage.getUsed() / usage.getCommitted(); |
| return Math.round(used * 1000); |
| } |
| } |
| |
| public synchronized boolean shouldFreeUpSpace() { |
| int usage = getMemoryUsage(); |
| long now = System.currentTimeMillis(); |
| |
| boolean detectedGC = false; |
| if (usage < lastUsage) { |
| lastGCDetected = now; |
| detectedGC = true; |
| } |
| |
| lastUsage = usage; |
| |
| long elapsed = now - lastFree; |
| long timeSinceLastGC = now - lastGCDetected; |
| |
| if (usage > criticalThresholdPromille && elapsed > minFreeCriticalWaitMS) { |
| lastFree = now; |
| return true; |
| } else if (usage > thresholdPromille && !detectedGC) { |
| if (elapsed > minFreeWaitElapsedMS || timeSinceLastGC > minGCWaitMS) { |
| lastFree = now; |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| } |
| |
| class MemoryUser extends Exitable implements Runnable { |
| private final Queue<Filler> cache = new ArrayDeque<Filler>(); |
| private final MemoryWatcher watcher; |
| |
| private void load() { |
| if (watcher.shouldFreeUpSpace()) { |
| int toRemove = cache.size() / 5; |
| for (int i = 0; i < toRemove; i++) { |
| cache.remove(); |
| } |
| } |
| cache.add(new Filler()); |
| } |
| |
| public MemoryUser(String mxBeanName) { |
| watcher = new MemoryWatcher(mxBeanName); |
| } |
| |
| @Override |
| public void run() { |
| for (int i = 0; i < 200; i++) { |
| load(); |
| } |
| |
| while (!shouldExit()) { |
| load(); |
| } |
| } |
| } |
| |
| class GCLockerStresser extends Exitable implements Runnable { |
| static native void fillWithRandomValues(byte[] array); |
| |
| @Override |
| public void run() { |
| byte[] array = new byte[1024 * 1024]; |
| while (!shouldExit()) { |
| fillWithRandomValues(array); |
| } |
| } |
| } |
| |
| public class TestGCLocker { |
| private static Exitable startGCLockerStresser(String name) { |
| GCLockerStresser task = new GCLockerStresser(); |
| |
| Thread thread = new Thread(task); |
| thread.setName(name); |
| thread.setPriority(Thread.MIN_PRIORITY); |
| thread.start(); |
| |
| return task; |
| } |
| |
| private static Exitable startMemoryUser(String mxBeanName) { |
| MemoryUser task = new MemoryUser(mxBeanName); |
| |
| Thread thread = new Thread(task); |
| thread.setName("Memory User"); |
| thread.start(); |
| |
| return task; |
| } |
| |
| public static void main(String[] args) { |
| System.loadLibrary("TestGCLocker"); |
| |
| long durationMinutes = args.length > 0 ? Long.parseLong(args[0]) : 5; |
| String mxBeanName = args.length > 1 ? args[1] : null; |
| |
| long startMS = System.currentTimeMillis(); |
| |
| Exitable stresser1 = startGCLockerStresser("GCLockerStresser1"); |
| Exitable stresser2 = startGCLockerStresser("GCLockerStresser2"); |
| Exitable memoryUser = startMemoryUser(mxBeanName); |
| |
| long durationMS = durationMinutes * 60 * 1000; |
| while ((System.currentTimeMillis() - startMS) < durationMS) { |
| ThreadUtils.sleep(10 * 1010); |
| } |
| |
| stresser1.exit(); |
| stresser2.exit(); |
| memoryUser.exit(); |
| } |
| } |