RFC 7038914: VM could throw uncaught OOME in ReferenceHandler thread

[Thomas Schatzl]

Hi all,

On Fri, 2013-05-10 at 12:52 +0200, Peter Levart wrote:
> Hi David, Thomas,
> 
> I think I understand you now, David. You want to minimize the 
> possibility of vacuously passing the test. So here's my attempt at that:
> 
> 
> public class OOMEInReferenceHandler {
>      static Object[] fillHeap() {
>          Object[] first = null, last = null;
>          int size = 1 << 20;
>          while (size > 0) {
>              try {
> [... new reproducer ...]


> [...]
> 
> To be sure the order of class referencing in handlers is not disturbed 
> by changes in compilers, I suggest the patch to be modified to this more 
> explicit variant:
> 
>                          try {
>                              try {
>                                  lock.wait();
>                              } catch (InterruptedException  x) { }
>                          } catch (OutOfMemoryError x) {}
> 
> 
> ..which also passes the test.

  I updated the test program and the patch in java.lang.ref.Reference
accordingly.

As for the problem of reproducibility, in my tests I had a 100%
reproduction rate with the previous version of the test.

However, now I also set -XX:-UseTLAB and -Xmx16M in the test program as
suggested in some other emails.

I will report back with a new webrev after some testing on more
platforms as suggested by David.

Hth,
Thomas