Name: agR10195 Date: 02/12/2004



The test Test1 gets each memory pool and tests if the pool supports usage
threshold. If yes, then the test sets usage threshold that is equal to "max"
value and then "used" value. The second invocation crashes Tiger-b37 debug
Server and Client VM on all platforms.

import java.io.*;
import java.util.*;
import java.lang.management.*;

public class Test1 {
    public static void main(String[] argv) {
        List pools = ManagementFactory.getMemoryPoolMBeans();

        for (int i = 0; i < pools.size(); i++) {
            MemoryPoolMBean pool = (MemoryPoolMBean) pools.get(i);
            System.out.println(i + " pool " + pool.getName());
            
            boolean isSupported = pool.isUsageThresholdSupported();
            long max = Math.abs(pool.getUsage().getMax());
            
            if (!isSupported)
                continue;

            System.out.println(" setting " + max);
     pool.setUsageThreshold(max);
            long used = pool.getUsage().getUsed();
            System.out.println(" setting " + used);
            pool.setUsageThreshold(used);
            System.out.println(" done");
        }
    }
}

% ../jdk1.5.0-b37/solaris-sparc/bin/java_g Test1
0 pool Code Cache
  setting 33554432
  setting 1114944
# To suppress the following error report, specify this argument
# after -XX: or in .hotspotrc: SuppressErrorAt=/lowMemoryDetector.cpp:263]
#
# An unexpected error has been detected by HotSpot Virtual Machine:
#
# Internal Error (/BUILD_AREA/jdk1.5.0/hotspot/src/share/vm/services/lowMemoryD
etector.cpp, 263 [ Patched ]), pid=17003, tid=1
#
# Java VM: Java HotSpot(TM) Client VM (1.5.0-beta2-b37-debug mixed mode)
#
# Error: assert(!(is_over_high && is_below_low),"Can't be both true")
# An error report file with more information is saved as hs_err_pid17003.log
#
# If you would like to submit a bug report, please visit:
# http://java.sun.com/webapps/bugreport/crash.jsp
#
Current thread is 1
Dumping core ...
Abort

% ../jdk1.5.0-b37/solaris-sparc/bin/java -server Test1
0 pool Code Cache
  setting 33554432
  setting 297728
  done
1 pool Eden Space
2 pool Survivor Space 1
3 pool Survivor Space 2
4 pool Tenured Gen
  setting 44761088
  setting 0
  done
5 pool Perm Gen
  setting 67108864
  setting 1499272
  done

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