--- /dev/null	2018-12-03 11:58:50.256341286 +0100
+++ new/test/hotspot/jtreg/gc/shenandoah/TestStringInternCleanup.java	2018-12-03 17:49:19.343608314 +0100
@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2017, 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 TestStringInternCleanup
+ * @summary Check that Shenandoah cleans up interned strings
+ * @key gc
+ * @requires vm.gc.Shenandoah
+ *
+ * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:+ClassUnloadingWithConcurrentMark -Xmx64m -XX:ShenandoahGCHeuristics=passive      -XX:+ShenandoahDegeneratedGC -XX:+ShenandoahVerify TestStringInternCleanup
+ * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:+ClassUnloadingWithConcurrentMark -Xmx64m -XX:ShenandoahGCHeuristics=passive      -XX:-ShenandoahDegeneratedGC -XX:+ShenandoahVerify TestStringInternCleanup
+ * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:+ClassUnloadingWithConcurrentMark -Xmx64m -XX:ShenandoahGCHeuristics=passive      -XX:+ShenandoahDegeneratedGC                       TestStringInternCleanup
+ * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:+ClassUnloadingWithConcurrentMark -Xmx64m -XX:ShenandoahGCHeuristics=passive      -XX:-ShenandoahDegeneratedGC                       TestStringInternCleanup
+ *
+ * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:+ClassUnloadingWithConcurrentMark -Xmx64m -XX:ShenandoahGCHeuristics=aggressive                         TestStringInternCleanup
+ *
+ * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:+ClassUnloadingWithConcurrentMark -Xmx64m -XX:ShenandoahGCHeuristics=adaptive     -XX:+ShenandoahVerify TestStringInternCleanup
+ * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:+ClassUnloadingWithConcurrentMark -Xmx64m -XX:ShenandoahGCHeuristics=traversal    -XX:+ShenandoahVerify TestStringInternCleanup
+ *
+ * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:+ClassUnloadingWithConcurrentMark -Xmx64m -XX:ShenandoahGCHeuristics=adaptive                           TestStringInternCleanup
+ * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:+ClassUnloadingWithConcurrentMark -Xmx64m -XX:ShenandoahGCHeuristics=static                             TestStringInternCleanup
+ * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:+ClassUnloadingWithConcurrentMark -Xmx64m -XX:ShenandoahGCHeuristics=compact                            TestStringInternCleanup
+ * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:+ClassUnloadingWithConcurrentMark -Xmx64m -XX:ShenandoahGCHeuristics=traversal                          TestStringInternCleanup
+ *
+ * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:-ClassUnloadingWithConcurrentMark -Xmx64m                                                               TestStringInternCleanup
+ */
+
+public class TestStringInternCleanup {
+
+    static final int COUNT = 1_000_000;
+    static final int WINDOW = 1_000;
+
+    static final String[] reachable = new String[WINDOW];
+
+    public static void main(String[] args) throws Exception {
+        int rIdx = 0;
+        for (int c = 0; c < COUNT; c++) {
+            reachable[rIdx] = ("LargeInternedString" + c).intern();
+            rIdx++;
+            if (rIdx >= WINDOW) {
+                rIdx = 0;
+            }
+        }
+    }
+
+}