--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/jtreg/gc/shenandoah/mxbeans/TestChurnNotifications.java	Mon Dec 10 15:47:44 2018 +0100
@@ -0,0 +1,115 @@
+/*
+ * Copyright (c) 2018, Red Hat, Inc. All rights reserved.
+ *
+ * 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.
+ *
+ */
+
+/*
+ * @test TestChurnNotifications
+ * @summary Check that MX notifications are reported for all cycles
+ * @requires vm.gc.Shenandoah
+ *
+ * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=passive      -XX:+ShenandoahDegeneratedGC -Dprecise=true  TestChurnNotifications
+ * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=passive      -XX:-ShenandoahDegeneratedGC -Dprecise=true  TestChurnNotifications
+ *
+ * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=aggressive   -Dprecise=false TestChurnNotifications
+ *
+ * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=adaptive     -Dprecise=false TestChurnNotifications
+ * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=static       -Dprecise=false TestChurnNotifications
+ * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=compact      -Dprecise=false TestChurnNotifications
+ * @run main/othervm -Xmx128m -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=traversal    -Dprecise=false TestChurnNotifications
+ */
+
+import java.util.*;
+import java.util.concurrent.atomic.*;
+import javax.management.*;
+import java.lang.management.*;
+import javax.management.openmbean.*;
+
+import com.sun.management.GarbageCollectionNotificationInfo;
+
+public class TestChurnNotifications {
+
+    static final long HEAP_MB = 128;                           // adjust for test configuration above
+    static final long TARGET_MB = Long.getLong("target", 8_000); // 8 Gb allocation
+
+    // Should we track the churn precisely?
+    // Precise tracking is only reliable when GC is fully stop-the-world. Otherwise,
+    // we cannot tell, looking at heap used before/after, what was the GC churn.
+    static final boolean PRECISE = Boolean.getBoolean("precise");
+
+    static final long M = 1024 * 1024;
+
+    static volatile Object sink;
+
+    public static void main(String[] args) throws Exception {
+        final AtomicLong churnBytes = new AtomicLong();
+
+        NotificationListener listener = new NotificationListener() {
+            @Override
+            public void handleNotification(Notification n, Object o) {
+                if (n.getType().equals(GarbageCollectionNotificationInfo.GARBAGE_COLLECTION_NOTIFICATION)) {
+                    GarbageCollectionNotificationInfo info = GarbageCollectionNotificationInfo.from((CompositeData) n.getUserData());
+                    Map<String, MemoryUsage> mapBefore = info.getGcInfo().getMemoryUsageBeforeGc();
+                    Map<String, MemoryUsage> mapAfter = info.getGcInfo().getMemoryUsageAfterGc();
+
+                    MemoryUsage before = mapBefore.get("Shenandoah");
+                    MemoryUsage after = mapAfter.get("Shenandoah");
+
+                    if ((before != null) && (after != null)) {
+                        long diff = before.getUsed() - after.getUsed();
+                        if (diff > 0) {
+                            churnBytes.addAndGet(diff);
+                        }
+                    }
+                }
+            }
+        };
+
+        for (GarbageCollectorMXBean bean : ManagementFactory.getGarbageCollectorMXBeans()) {
+            ((NotificationEmitter) bean).addNotificationListener(listener, null, null);
+        }
+
+        final int size = 100_000;
+        long count = TARGET_MB * 1024 * 1024 / (16 + 4 * size);
+
+        long mem = count * (16 + 4 * size);
+
+        for (int c = 0; c < count; c++) {
+            sink = new int[size];
+        }
+
+        System.gc();
+
+        Thread.sleep(1000);
+
+        long actual = churnBytes.get();
+
+        long minExpected = PRECISE ? (mem - HEAP_MB * 1024 * 1024) : 1;
+        long maxExpected = mem + HEAP_MB * 1024 * 1024;
+
+        String msg = "Expected = [" + minExpected / M + "; " + maxExpected / M + "] (" + mem / M + "), actual = " + actual / M;
+        if (minExpected < actual && actual < maxExpected) {
+            System.out.println(msg);
+        } else {
+            throw new IllegalStateException(msg);
+        }
+    }
+}