1 /*

     2  * Copyright (c) 2017, 2018, Red Hat, Inc. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  */

    23 

    24 /**

    25  * @test TestElasticTLABDecay

    26  * @key gc

    27  * @requires vm.gc.Epsilon

    28  * @summary Epsilon is able to work with/without elastic TLABs

    29  *

    30  * @run main/othervm -Xmx1g -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC -XX:+EpsilonElasticTLAB -XX:-EpsilonElasticTLABDecay                               TestElasticTLABDecay

    31  * @run main/othervm -Xmx1g -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC -XX:+EpsilonElasticTLAB -XX:+EpsilonElasticTLABDecay -XX:EpsilonTLABDecayTime=1    TestElasticTLABDecay

    32  * @run main/othervm -Xmx1g -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC -XX:+EpsilonElasticTLAB -XX:+EpsilonElasticTLABDecay -XX:EpsilonTLABDecayTime=100  TestElasticTLABDecay

    33  */

    34 

    35 import java.util.Random;

    36 

    37 public class TestElasticTLABDecay {

    38 

    39   static long SEED = Long.getLong("seed", System.nanoTime());

    40   static int COUNT = Integer.getInteger("count", 3000); // ~500 MB allocation

    41 

    42   static byte[][] arr;

    43 

    44   public static void main(String[] args) throws Exception {

    45     Random r = new Random(SEED);

    46 

    47     arr = new byte[COUNT * 100][];

    48     for (int c = 0; c < COUNT; c++) {

    49       arr[c] = new byte[c * 100];

    50       for (int v = 0; v < c; v++) {

    51         arr[c][v] = (byte)(r.nextInt(255) & 0xFF);

    52       }

    53       Thread.sleep(5);

    54     }

    55 

    56     r = new Random(SEED);

    57     for (int c = 0; c < COUNT; c++) {

    58       byte[] b = arr[c];

    59       if (b.length != (c * 100)) {

    60         throw new IllegalStateException("Failure: length = " + b.length + ", need = " + (c*100));

    61       }

    62       for (int v = 0; v < c; v++) {

    63         byte actual = b[v];

    64         byte expected = (byte)(r.nextInt(255) & 0xFF);

    65         if (actual != expected) {

    66           throw new IllegalStateException("Failure: expected = " + expected + ", actual = " + actual);

    67         }

    68       }

    69     }

    70   }

    71 }