jdk8-mips64-public/hotspot: test/gc/g1/TestHumongousShrinkHeap.java@14b8221771dc (annotated)

test/gc/g1/TestHumongousShrinkHeap.java@14b8221771dc (annotated)

test/gc/g1/TestHumongousShrinkHeap.java

Wed, 03 Sep 2014 09:25:44 +0200

author: tschatzl
date: Wed, 03 Sep 2014 09:25:44 +0200
changeset 7097: 14b8221771dc
parent 7096: b1266b08b994
child 7175: 9b8bd21b6823
permissions: -rw-r--r--

Merge

 /*
  * Copyright (c) 2014, 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 TestHumongousShrinkHeap
  * @bug 8036025 8056043
  * @summary Verify that heap shrinks after GC in the presence of fragmentation due to humongous objects
  * @library /testlibrary
  * @run main/othervm -XX:MinHeapFreeRatio=10 -XX:MaxHeapFreeRatio=50 -XX:+UseG1GC -XX:G1HeapRegionSize=1M -verbose:gc TestHumongousShrinkHeap
  */
 import java.lang.management.ManagementFactory;
 import java.lang.management.MemoryUsage;
 import java.util.ArrayList;
 import java.util.List;
 import sun.management.ManagementFactoryHelper;
 import static com.oracle.java.testlibrary.Asserts.*;
 public class TestHumongousShrinkHeap {
     public static final String MIN_FREE_RATIO_FLAG_NAME = "MinHeapFreeRatio";
     public static final String MAX_FREE_RATIO_FLAG_NAME = "MaxHeapFreeRatio";
     private static final ArrayList<ArrayList<byte[]>> garbage = new ArrayList<>();
     private static final int PAGE_SIZE = 1024 * 1024; // 1M
     private static final int PAGES_NUM = 5;
     public static void main(String[] args) {
         new TestHumongousShrinkHeap().test();
     }
     private final void test() {
         System.gc();
         MemoryUsagePrinter.printMemoryUsage("init");
         eat();
         MemoryUsagePrinter.printMemoryUsage("eaten");
         MemoryUsage muFull = ManagementFactory.getMemoryMXBean().getHeapMemoryUsage();
         free();
         MemoryUsagePrinter.printMemoryUsage("free");
         MemoryUsage muFree = ManagementFactory.getMemoryMXBean().getHeapMemoryUsage();
         assertLessThan(muFree.getCommitted(), muFull.getCommitted(), String.format(
                 "committed free heap size is not less than committed full heap size, heap hasn't been shrunk?%n"
                 + "%s = %s%n%s = %s",
                 MIN_FREE_RATIO_FLAG_NAME,
                 ManagementFactoryHelper.getDiagnosticMXBean().getVMOption(MIN_FREE_RATIO_FLAG_NAME).getValue(),
                 MAX_FREE_RATIO_FLAG_NAME,
                 ManagementFactoryHelper.getDiagnosticMXBean().getVMOption(MAX_FREE_RATIO_FLAG_NAME).getValue()
         ));
     }
     private void eat() {
         int HumongousObjectSize = Math.round(.9f * PAGE_SIZE);
         System.out.println("Will allocate objects of size=" +
                 MemoryUsagePrinter.humanReadableByteCount(HumongousObjectSize, true));
         for (int i = 0; i < PAGES_NUM; i++) {
             ArrayList<byte[]> stuff = new ArrayList<>();
             eatList(stuff, 100, HumongousObjectSize);
             MemoryUsagePrinter.printMemoryUsage("eat #" + i);
             garbage.add(stuff);
         }
     }
     private void free() {
         // do not free last one list
         garbage.subList(0, garbage.size() - 1).clear();
         // do not free last one element from last list
         ArrayList stuff = garbage.get(garbage.size() - 1);
         stuff.subList(0, stuff.size() - 1).clear();
         System.gc();
     }
     private static void eatList(List garbage, int count, int size) {
         for (int i = 0; i < count; i++) {
             garbage.add(new byte[size]);
         }
     }
 }
 /**
  * Prints memory usage to standard output
  */
 class MemoryUsagePrinter {
     public static String humanReadableByteCount(long bytes, boolean si) {
         int unit = si ? 1000 : 1024;
         if (bytes < unit) {
             return bytes + " B";
         }
         int exp = (int) (Math.log(bytes) / Math.log(unit));
         String pre = (si ? "kMGTPE" : "KMGTPE").charAt(exp - 1) + (si ? "" : "i");
         return String.format("%.1f %sB", bytes / Math.pow(unit, exp), pre);
     }
     public static void printMemoryUsage(String label) {
         MemoryUsage memusage = ManagementFactory.getMemoryMXBean().getHeapMemoryUsage();
         float freeratio = 1f - (float) memusage.getUsed() / memusage.getCommitted();
         System.out.format("[%-24s] init: %-7s, used: %-7s, comm: %-7s, freeRatio ~= %.1f%%%n",
                 label,
                 humanReadableByteCount(memusage.getInit(), true),
                 humanReadableByteCount(memusage.getUsed(), true),
                 humanReadableByteCount(memusage.getCommitted(), true),
                 freeratio * 100
         );
     }
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

test/gc/g1/TestHumongousShrinkHeap.java@14b8221771dc (annotated)

test/gc/g1/TestHumongousShrinkHeap.java