--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/jtreg/gc/shenandoah/TestAllocHumongousFragment.java	Mon Dec 10 15:47:44 2018 +0100
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2016, 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 TestAllocHumongousFragment
+ * @summary Make sure Shenandoah can recover from humongous allocation fragmentation
+ * @key gc
+ * @requires vm.gc.Shenandoah
+ *
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=passive    -XX:-ShenandoahDegeneratedGC     -XX:+ShenandoahVerify TestAllocHumongousFragment
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=passive    -XX:+ShenandoahDegeneratedGC     -XX:+ShenandoahVerify TestAllocHumongousFragment
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=passive    -XX:-ShenandoahDegeneratedGC                           TestAllocHumongousFragment
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=passive    -XX:+ShenandoahDegeneratedGC                           TestAllocHumongousFragment
+ *
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=aggressive -XX:+ShenandoahOOMDuringEvacALot -XX:+ShenandoahVerify TestAllocHumongousFragment
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=aggressive -XX:+ShenandoahAllocFailureALot  -XX:+ShenandoahVerify TestAllocHumongousFragment
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=aggressive -XX:+ShenandoahOOMDuringEvacALot                       TestAllocHumongousFragment
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=aggressive -XX:+ShenandoahAllocFailureALot                        TestAllocHumongousFragment
+ *
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=adaptive     -XX:+ShenandoahVerify TestAllocHumongousFragment
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=traversal    -XX:+ShenandoahVerify TestAllocHumongousFragment
+ *
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=adaptive     TestAllocHumongousFragment
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=static       TestAllocHumongousFragment
+ * @run main/othervm -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahTargetNumRegions=2048 -XX:ShenandoahGCHeuristics=traversal    TestAllocHumongousFragment
+ */
+
+import java.util.*;
+import java.util.concurrent.*;
+
+public class TestAllocHumongousFragment {
+
+    static final long TARGET_MB = Long.getLong("target", 30_000); // 30 Gb allocations
+    static final long LIVE_MB   = Long.getLong("occupancy", 700); // 700 Mb alive
+
+    static volatile Object sink;
+
+    static List<int[]> objects;
+
+    public static void main(String[] args) throws Exception {
+        final int min = 128 * 1024;
+        final int max = 16 * 1024 * 1024;
+        final long count = TARGET_MB * 1024 * 1024 / (16 + 4 * (min + (max - min) / 2));
+
+        objects = new ArrayList<>();
+        long current = 0;
+
+        Random r = new Random();
+        for (long c = 0; c < count; c++) {
+            while (current > LIVE_MB * 1024 * 1024) {
+                int idx = ThreadLocalRandom.current().nextInt(objects.size());
+                int[] remove = objects.remove(idx);
+                current -= remove.length * 4 + 16;
+            }
+
+            int[] newObj = new int[min + r.nextInt(max - min)];
+            current += newObj.length * 4 + 16;
+            objects.add(newObj);
+            sink = new Object();
+
+            System.out.println("Allocated: " + (current / 1024 / 1024) + " Mb");
+        }
+    }
+
+}