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 TestNoEagerReclaimOfHumongousRegions
  26  * @bug 8139424
  27  * @summary Test to check that a live humongous object is not eagerly reclaimed. This is a regression test for
  28  *          8139424 and the test will crash if an eager reclaim occur. The test is not 100% deterministic and
  29  *          might pass even if there are problems in the code, but it will never crash unless there is a problem.
  30  * @requires vm.gc=="G1" | vm.gc=="null"
  31  * @key gc
  32  * @library /testlibrary /test/lib
  33  * @modules java.base/sun.misc
  34  * @build TestNoEagerReclaimOfHumongousRegions
  35  * @run main ClassFileInstaller sun.hotspot.WhiteBox
  36  *                              sun.hotspot.WhiteBox$WhiteBoxPermission
  37  * @run main/othervm -Xbootclasspath/a:. -XX:+PrintGC -XX:+UseG1GC -XX:MaxTenuringThreshold=0 -XX:G1RSetSparseRegionEntries=32 -XX:G1HeapRegionSize=1m -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -XX:+UnlockExperimentalVMOptions -XX:+G1TraceEagerReclaimHumongousObjects TestNoEagerReclaimOfHumongousRegions
  38  */
  39 
  40 import java.util.LinkedList;
  41 
  42 import sun.hotspot.WhiteBox;
  43 
  44 public class TestNoEagerReclaimOfHumongousRegions {
  45     // Helper class to keep reference to humongous byte[].
  46     static class LargeRef {
  47         private byte[] _ref;
  48 
  49         LargeRef(byte[] ref) {
  50             _ref = ref;
  51         }
  52 
  53         byte[] ref() { return _ref; }
  54     }
  55 
  56     static LargeRef humongous_reference_holder;
  57 

  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 TestNoEagerReclaimOfHumongousRegions
  26  * @bug 8139424
  27  * @summary Test to check that a live humongous object is not eagerly reclaimed. This is a regression test for
  28  *          8139424 and the test will crash if an eager reclaim occur. The test is not 100% deterministic and
  29  *          might pass even if there are problems in the code, but it will never crash unless there is a problem.
  30  * @requires vm.gc=="G1" | vm.gc=="null"
  31  * @key gc
  32  * @library /testlibrary /test/lib
  33  * @modules java.base/sun.misc
  34  * @build TestNoEagerReclaimOfHumongousRegions
  35  * @run main ClassFileInstaller sun.hotspot.WhiteBox
  36  *                              sun.hotspot.WhiteBox$WhiteBoxPermission
  37  * @run main/othervm -Xbootclasspath/a:. -Xlog:gc,gc+humongous=debug -XX:+UseG1GC -XX:MaxTenuringThreshold=0 -XX:G1RSetSparseRegionEntries=32 -XX:G1HeapRegionSize=1m -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI TestNoEagerReclaimOfHumongousRegions
  38  */
  39 
  40 import java.util.LinkedList;
  41 
  42 import sun.hotspot.WhiteBox;
  43 
  44 public class TestNoEagerReclaimOfHumongousRegions {
  45     // Helper class to keep reference to humongous byte[].
  46     static class LargeRef {
  47         private byte[] _ref;
  48 
  49         LargeRef(byte[] ref) {
  50             _ref = ref;
  51         }
  52 
  53         byte[] ref() { return _ref; }
  54     }
  55 
  56     static LargeRef humongous_reference_holder;
  57