Name: szC45993 Date: 08/05/99



Some set of debugging flags, used
for Tonga/src/nsk/arguments/args00134 test, crashes
java_g (HotSpot Client VM 1.3beta, mixed mode, debug build l) on WinNT
(Pentium II, 350MHz, 128Mb RAM, Windows NT 4.0 Workstation).
See log and sources below.

[#] cd f:/ld24/java/zss/TONGA_WSs/testbase_js/src/nsk/arguments/args00134
[#] f:/ld25/java/dest/jdk1.3L/win32/bin/java_g -version
java version "1.3"
HotSpot Client VM (1.3beta, mixed mode, debug build l)
[Verifying threads permgen oldgen ct newgen rset syms strs lkup zone dict hand C-heap ]
[#] f:/ld25/java/dest/jdk1.3L/win32/bin/javac args00134.java
[#] f:/ld25/java/dest/jdk1.3L/win32/bin/java_g -verify -XX:Flags=f:/ld24/java/zss/TONGA_WSs/testbase_js/src/nsk/arguments/args00134/args00134.opts args00134

VM option '+PrintVMMessages'
VM option '+PromptForDebug'
VM option '+TraceVMOperation'
VM option '+PrintCompilation'
VM option '+PrintAssembly'
VM option '+PrintNMethods'
VM option '+PrintNativeNMethods'
VM option '+PrintCodeCache'
VM option '+PrintCodeCache2'
VM option '+DumpEventsAtError'
VM option '+PrintStubCode'
VM option '+ProfilerPrintByteCodeStatistics'
VM option '+ProfilerRecordPC'
VM option '+ProfilerCheckIntervals'
VM option '+PrintJVMWarnings'

...

#
# HotSpot Virtual Machine Error, Internal Error
#
# Fatal: memory stomping error
#
# Error ID: D:/localbuilds/hotspot_client1.3_beta1_compiler1\src\share\vm\runtime\os.cpp, 390
#


SOURCES:
========

#-------------------- args00134.opts:
+PrintVMMessages
+PromptForDebug
+TraceVMOperation
+PrintCompilation
+PrintAssembly
+PrintNMethods
+PrintNativeNMethods
+PrintCodeCache
+PrintCodeCache2
+DumpEventsAtError
+PrintStubCode
+ProfilerPrintByteCodeStatistics
+ProfilerRecordPC
+ProfilerCheckIntervals
+PrintJVMWarnings


//--------------------- args00134.java:
//args00134.java
/* This test simply creates a series of circularly
 * linked memeory objects which should be able to be
 * GC'd
 */


class MemoryObject
{
    byte array[];
    MemoryObject next;
    MemoryObject previous;

    public MemoryObject(int size)
    {
        array = new byte[size];
    }
}

class args00134
{
    static final int ARRAY_SIZE = 100;
    static final int OBJECT_SIZE = 10;
    static final int LOOP_COUNT = 5;
    static final int CIRCULARITY_SIZE = 3;

    static MemoryObject memoryArray[] = new MemoryObject[ARRAY_SIZE];

    public static void main(String args[])
    {
        for (int j = 0; j < LOOP_COUNT; j++)
        {
            System.out.println(j + ": " + Runtime.getRuntime().freeMemory());
            for (int i = 0; i < ARRAY_SIZE; i ++)
            {
                memoryArray[i] = new MemoryObject(OBJECT_SIZE);
                makeCircular(memoryArray[i], CIRCULARITY_SIZE);
            }
        }

        // if there's any memory left, let's assume it's okay
        System.out.println("Test passed.");

    }

    public static void makeCircular(MemoryObject mObj, int depth)
    {
MemoryObject tmpObj = mObj;

        for (int i = 0; i < depth; i++)
        {
            tmpObj.next = new MemoryObject(OBJECT_SIZE);
            tmpObj= tmpObj.next;
        }
tmpObj.next = mObj;
    }

    public static void confirmCircular(MemoryObject mObj)
    {
int count = 0;
MemoryObject mObj2 = mObj;
while (mObj2.next != mObj)
{
count++;
mObj2 = mObj2.next;
}
System.out.println("Circularity level: " + count);
    }
}
//---------------------

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