--- /dev/null	2018-11-14 11:51:49.720116297 -0800
+++ new/test/hotspot/jtreg/runtime/appcds/LotsOfClasses.java	2018-11-16 19:18:42.818202428 -0800
@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2018, 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.
+ *
+ */
+
+import java.net.URI;
+import java.nio.file.DirectoryStream;
+import java.nio.file.Files;
+import java.nio.file.FileSystem;
+import java.nio.file.FileSystems;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import jdk.test.lib.cds.CDSTestUtils;
+import jdk.test.lib.cds.CDSOptions;
+import jdk.test.lib.process.OutputAnalyzer;
+
+/*
+ * @test
+ * @summary Try to archive lots of classes by searching for classes from the jrt:/ file system. With JDK 12
+ *          this will produce an archive with over 30,000 classes.
+ * @requires vm.cds
+ * @library /test/lib
+ * @run driver/timeout=500 LotsOfClasses
+ */
+
+public class LotsOfClasses {
+    static Pattern pattern;
+
+    public static void main(String[] args) throws Throwable {
+        ArrayList<String> list = new ArrayList<>();
+        findAllClasses(list);
+
+        CDSOptions opts = new CDSOptions();
+        opts.setClassList(list);
+        opts.addSuffix("--add-modules"); 
+        opts.addSuffix("ALL-SYSTEM");
+        opts.addSuffix("-Xlog:hashtables");
+
+        OutputAnalyzer out = CDSTestUtils.createArchive(opts);
+        CDSTestUtils.checkDump(out);
+    }
+
+    static void findAllClasses(ArrayList<String> list) throws Throwable {
+        // Find all the classes in the jrt file system
+        pattern = Pattern.compile("/modules/[a-z.]*[a-z]+/([^-]*)[.]class");
+        FileSystem fs = FileSystems.getFileSystem(URI.create("jrt:/"));
+        Path base = fs.getPath("/modules/");
+        find(base, list);
+    }
+
+    static void find(Path p, ArrayList<String> list) throws Throwable {
+        try (DirectoryStream<Path> stream = Files.newDirectoryStream(p)) {
+                for (Path entry: stream) {
+                    Matcher matcher = pattern.matcher(entry.toString());
+                    if (matcher.find()) {
+                        String className = matcher.group(1);
+                        list.add(className);
+                        //System.out.println(className);
+                    }
+                    try {
+                        find(entry, list);
+                    } catch (Throwable t) {}
+                }
+            }
+    }
+}