1 /*
   2  * Copyright (c) 2018, Red Hat, Inc. All rights reserved.
   3  *
   4  * This code is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This code is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  11  * version 2 for more details (a copy is included in the LICENSE file that
  12  * accompanied this code).
  13  *
  14  * You should have received a copy of the GNU General Public License version
  15  * 2 along with this work; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  19  * or visit www.oracle.com if you need additional information or have any
  20  * questions.
  21  *
  22  */
  23 
  24 /*
  25  * @test TestChurnNotifications
  26  * @summary Check that MX notifications are reported for all cycles
  27  * @requires vm.gc.Shenandoah
  28  *
  29  * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=passive      -XX:+ShenandoahDegeneratedGC -Dprecise=true  TestChurnNotifications
  30  * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=passive      -XX:-ShenandoahDegeneratedGC -Dprecise=true  TestChurnNotifications
  31  *
  32  * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=aggressive   -Dprecise=false TestChurnNotifications
  33  *
  34  * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=adaptive     -Dprecise=false TestChurnNotifications
  35  * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=static       -Dprecise=false TestChurnNotifications
  36  * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=compact      -Dprecise=false TestChurnNotifications
  37  * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=traversal    -Dprecise=false TestChurnNotifications
  38  */
  39 
  40 import java.util.*;
  41 import java.util.concurrent.atomic.*;
  42 import javax.management.*;
  43 import java.lang.management.*;
  44 import javax.management.openmbean.*;
  45 
  46 import com.sun.management.GarbageCollectionNotificationInfo;
  47 
  48 public class TestChurnNotifications {
  49 
  50     static final long HEAP_MB = 128;                           // adjust for test configuration above
  51     static final long TARGET_MB = Long.getLong("target", 8_000); // 8 Gb allocation
  52 
  53     // Should we track the churn precisely?
  54     // Precise tracking is only reliable when GC is fully stop-the-world. Otherwise,
  55     // we cannot tell, looking at heap used before/after, what was the GC churn.
  56     static final boolean PRECISE = Boolean.getBoolean("precise");
  57 
  58     static final long M = 1024 * 1024;
  59 
  60     static volatile Object sink;
  61 
  62     public static void main(String[] args) throws Exception {
  63         final AtomicLong churnBytes = new AtomicLong();
  64 
  65         NotificationListener listener = new NotificationListener() {
  66             @Override
  67             public void handleNotification(Notification n, Object o) {
  68                 if (n.getType().equals(GarbageCollectionNotificationInfo.GARBAGE_COLLECTION_NOTIFICATION)) {
  69                     GarbageCollectionNotificationInfo info = GarbageCollectionNotificationInfo.from((CompositeData) n.getUserData());
  70                     Map<String, MemoryUsage> mapBefore = info.getGcInfo().getMemoryUsageBeforeGc();
  71                     Map<String, MemoryUsage> mapAfter = info.getGcInfo().getMemoryUsageAfterGc();
  72 
  73                     MemoryUsage before = mapBefore.get("Shenandoah");
  74                     MemoryUsage after = mapAfter.get("Shenandoah");
  75 
  76                     if ((before != null) && (after != null)) {
  77                         long diff = before.getUsed() - after.getUsed();
  78                         if (diff > 0) {
  79                             churnBytes.addAndGet(diff);
  80                         }
  81                     }
  82                 }
  83             }
  84         };
  85 
  86         for (GarbageCollectorMXBean bean : ManagementFactory.getGarbageCollectorMXBeans()) {
  87             ((NotificationEmitter) bean).addNotificationListener(listener, null, null);
  88         }
  89 
  90         final int size = 100_000;
  91         long count = TARGET_MB * 1024 * 1024 / (16 + 4 * size);
  92 
  93         long mem = count * (16 + 4 * size);
  94 
  95         for (int c = 0; c < count; c++) {
  96             sink = new int[size];
  97         }
  98 
  99         System.gc();
 100 
 101         Thread.sleep(1000);
 102 
 103         long actual = churnBytes.get();
 104 
 105         long minExpected = PRECISE ? (mem - HEAP_MB * 1024 * 1024) : 1;
 106         long maxExpected = mem + HEAP_MB * 1024 * 1024;
 107 
 108         String msg = "Expected = [" + minExpected / M + "; " + maxExpected / M + "] (" + mem / M + "), actual = " + actual / M;
 109         if (minExpected < actual && actual < maxExpected) {
 110             System.out.println(msg);
 111         } else {
 112             throw new IllegalStateException(msg);
 113         }
 114     }
 115 }