1 /*
   2 * Copyright (c) 2014, Oracle and/or its affiliates. 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 TestParallelGCThreads
  26  * @key gc
  27  * @bug 8059527
  28  * @summary Tests argument processing for ParallelGCThreads
  29  * @library /testlibrary
  30  * @run driver TestParallelGCThreads
  31  */
  32 
  33 import com.oracle.java.testlibrary.*;
  34 
  35 public class TestParallelGCThreads {
  36 
  37   public static void main(String args[]) throws Exception {
  38 
  39     // For each parallel collector (G1, Parallel, ParNew/CMS)
  40     for (String gc : new String[] {"G1", "Parallel", "ConcMarkSweep"}) {
  41 
  42       // Make sure the VM does not allow ParallelGCThreads set to 0
  43       String[] flags = new String[] {"-XX:+Use" + gc + "GC", "-XX:ParallelGCThreads=0", "-XX:+PrintFlagsFinal", "-version"};
  44       ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(flags);
  45       OutputAnalyzer output = new OutputAnalyzer(pb.start());
  46       output.shouldHaveExitValue(1);
  47 
  48       // Do some basic testing to ensure the flag updates the count
  49       for (long i = 1; i <= 3; i++) {
  50         flags = new String[] {"-XX:+Use" + gc + "GC", "-XX:ParallelGCThreads=" + i, "-XX:+PrintFlagsFinal", "-version"};
  51         long count = getParallelGCThreadCount(flags);
  52         Asserts.assertEQ(count, i, "Specifying ParallelGCThreads=" + i + " for " + gc + "GC does not set the thread count properly!");
  53       }
  54     }
  55   }
  56 
  57   public static long getParallelGCThreadCount(String flags[]) throws Exception {
  58     ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(flags);
  59     OutputAnalyzer output = new OutputAnalyzer(pb.start());
  60     output.shouldHaveExitValue(0);
  61     String stdout = output.getStdout();
  62     return FlagsValue.getFlagLongValue("ParallelGCThreads", stdout);
  63   }
  64 }