--- /dev/null 2018-01-19 14:57:15.000000000 -0800 +++ new/test/hotspot/jtreg/gc/g1/TestMixedOldGenCollectionUsage.java 2018-01-19 14:57:15.000000000 -0800 @@ -0,0 +1,163 @@ +/* + * 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. + */ + +/* + * @test TestMixedOldGenCollectionUsage.java + * @bug 8195115 + * @requires vm.gc.G1 + * @summary G1 Old Gen's CollectionUsage.used is zero after mixed GC which is incorrect + * @run main/othervm -Xmx64m -Xms64m -verbose:gc -XX:+UseG1GC TestMixedOldGenCollectionUsage + */ +import java.util.*; +import java.lang.management.*; + +// 8195115 says that for the "G1 Old Gen" MemoryPool, CollectionUsage.used +// is zero for G1 after a mixed collection. + +public class TestMixedOldGenCollectionUsage { + + private String poolName = "G1 Old Gen"; + private String collectorName = "G1 Young Generation"; + + public static void main(String [] args) { + TestMixedOldGenCollectionUsage t = new TestMixedOldGenCollectionUsage(); + t.run(); + } + + public TestMixedOldGenCollectionUsage() { + System.out.println("Monitor G1 Old Gen pool with G1 Young Generation collector."); + } + + public void run() { + // Find memory pool and collector + List pools = ManagementFactory.getMemoryPoolMXBeans(); + MemoryPoolMXBean pool = null; + boolean foundPool = false; + for (int i = 0; i < pools.size(); i++) { + pool = pools.get(i); + String name = pool.getName(); + if (name.contains(poolName)) { + System.out.println("Found pool: " + name); + foundPool = true; + break; + } + } + if (!foundPool) { + throw new RuntimeException(poolName + " not found, test with -XX:+UseG1GC"); + } + + List collectors = ManagementFactory.getGarbageCollectorMXBeans(); + GarbageCollectorMXBean collector = null; + boolean foundCollector = false; + for (int i = 0; i < collectors.size(); i++) { + collector = collectors.get(i); + String name = collector.getName(); + if (name.contains(collectorName)) { + System.out.println("Found collector: " + name); + foundCollector = true; + break; + } + } + if (!foundCollector) { + throw new RuntimeException(collectorName + " not found, test with -XX:+UseG1GC"); + } + + // Use some memory, enough that young, but not mixed, collections + // have happened. + allocationWork(20*1024*1024, 0); + System.out.println("Done allocationWork for pure young collections"); + + // Verify no non-zero result was stored + long usage = pool.getCollectionUsage().getUsed(); + System.out.println(poolName + ": usage after GC = " + usage); + if (usage > 0) { + throw new RuntimeException("Premature mixed collections(s)"); + } + + // Verify that collections were done + long collectionCount = collector.getCollectionCount(); + System.out.println(collectorName + ": collection count = " + + collectionCount); + long collectionTime = collector.getCollectionTime(); + System.out.println(collectorName + ": collection time = " + + collectionTime); + if (collectionCount <= 0) { + throw new RuntimeException("Collection count <= 0"); + } + if (collectionTime <= 0) { + throw new RuntimeException("Collector has not run"); + } + + // Must run with options to ensure no stop the world full GC, + // but at least one GC cycle that includes a mixed collection. + allocationWork(20*1024*1024, 10*1024*1024); + System.out.println("Done allocationWork for mixed collections"); + + usage = pool.getCollectionUsage().getUsed(); + System.out.println(poolName + ": usage after GC = " + usage); + if (usage <= 0) { + throw new RuntimeException(poolName + " found with zero usage"); + } + + long newCollectionCount = collector.getCollectionCount(); + System.out.println(collectorName + ": collection count = " + + newCollectionCount); + long newCollectionTime = collector.getCollectionTime(); + System.out.println(collectorName + ": collection time = " + + newCollectionTime); + if (newCollectionCount <= collectionCount) { + throw new RuntimeException("No new collection"); + } + if (newCollectionTime <= collectionTime) { + throw new RuntimeException("Collector has not run some more"); + } + + System.out.println("Test passed."); + } + + public void allocationWork(long persistentTarget, long target) { + long persistentSizeAllocated = 0; + long sizeAllocated = 0; + char[] template = new char[10240]; + Random rand = new Random(); + PrimitiveIterator.OfInt indexiter = rand.ints().iterator(); + PrimitiveIterator.OfInt valueiter = rand.ints().iterator(); + + Set persistentStrings = new HashSet<>(1000); + while (persistentSizeAllocated < persistentTarget) { + for (int i = 0; i < 100; i++) { + template[Math.abs(indexiter.next() % 10240)] = (char)valueiter.nextInt(); + persistentStrings.add(new String(template)); + } + persistentSizeAllocated += 100*10240*2; + } + while (sizeAllocated < target) { + Set strings = new HashSet<>(1000); + for (int i = 0; i < 1000; i++) { + template[Math.abs(indexiter.next() % 10240)] = (char)valueiter.nextInt(); + strings.add(new String(template)); + } + sizeAllocated += 1000*10240*2; + } + } +}