This is better (fixed a data race in Cleaner.clean()):
http://cr.openjdk.java.net/~plevart/jdk9-dev/OOMEInReferenceHandler/Investigation/webrev.05/
Regards, Peter
On 05/06/2015 07:13 PM, Peter Levart wrote:
Hi,
I might have a closure for this long beard issue [1] and I'd like to
propose a change [2].
It all started with [3] discussed here [4] which resulted in the fix
for one source of OutOfMemoryError(s) terminating ReferenceHandler
thread. With this fix, new test was added which started failing
intermittently indicating there is another source of
OutOfMemoryError(s) being thrown in ReferenceHandler. At that time,
the investigation [6] indicated that the source is "r instanceof
Cleaner" check and so another change was pushed [5]. The issue
JDK-8022321 is internal - I don't have a link. That change was 2-fold:
it added code to preload and pre-initialize Cleaner and
InterruptedException classes in ReferenceHandler.<clinit> and,
cowardly, surrounded "r instanceof Cleaner" check with OOME exception
handler. I'm pretty certain that pre-loading of the classes would have
been enough. At least it would have not sprung the confusion expressed
here [7].
But even that was not enough to prevent intermittent failures. I
realized that the test I devised still fails because of
Cleaner.clean() throwing OOME. Why this is possible is discussed in
the issue [1]. I even modified the test to reproduce such failure with
100% chance.
So here I propose two things in [2] :
- roll-back of the confusing "r instanceof Cleaner" OOME exception
handling to the shape of code predating change [5].
- add handling of OOME in the Cleaner.clean() with updated test that
checks the behaviour.
Regards, Peter
[1] https://bugs.openjdk.java.net/browse/JDK-8066859
[2]
http://cr.openjdk.java.net/~plevart/jdk9-dev/OOMEInReferenceHandler/Investigation/webrev.04/
[3] https://bugs.openjdk.java.net/browse/JDK-8015434
[4]
http://mail.openjdk.java.net/pipermail/core-libs-dev/2013-April/016510.html
[5] http://hg.openjdk.java.net/jdk9/dev/jdk/rev/d04102f69d46
[6]
https://www.mail-archive.com/core-libs-dev%40openjdk.java.net/msg23596.html
[7] https://bugs.openjdk.java.net/browse/JDK-8055232
