Analysis on JDK-8022321 java/lang/ref/OOMEInReferenceHandler.java fails intermittently

[David Holmes]

On 24/01/2014 6:10 AM, srikalyan wrote:
> Hi Peter, i have modified your code from
>
> r = pending;
> if (r != null) {
>       ......
>        TO
> if (pending != null) {
>       r = pending;
>
> This is because the r is used later in the code and must not be assigned
> pending unless it is not null(this was as is earlier).

If r is null, because pending is null then you perform the wait() and 
then continue - back to the top of the loop. There is no bug in Peter's 
code.

The new webrev is
> posted here
> http://cr.openjdk.java.net/~srikchan/Regression/JDK-8022321_OOMEInReferenceHandler-webrev-V2/
> . I ran a 1000 run and no failures so far, however i would like to run a
> couple more 1000 runs to assert the fix.
>
> PS: The description section of JEP-122
> (http://openjdk.java.net/jeps/122) says meta-data would be in native
> memory(not heap).

The class_mirror is a Java object not meta-data.

David

> --
> Thanks
> kalyan
> Ph: (408)-585-8040
>
>
> On 1/21/14, 2:31 PM, Peter Levart wrote:
>>
>> On 01/21/2014 07:17 PM, srikalyan wrote:
>>> Hi Peter/David, catching up after long weekend. Why would there be an
>>> OOME in object heap due to class loading in perm gen space ?
>>
>> The perm gen is not a problem her (JDK 8 does not have it and we see
>> OOME on JDK8 too). Each time a class is loaded, new java.lang.Class
>> object is allocated on heap.
>>
>> Regards, Peter
>>
>>> Please correct if i am missing something here. Meanwhile i will give
>>> the version of Reference Handler you both agreed on a try.
>>> --
>>> Thanks
>>> kalyan
>>> Ph: (408)-585-8040
>>>
>>> On 1/21/14, 7:24 AM, Peter Levart wrote:
>>>> On 01/21/2014 07:54 AM, Peter Levart wrote:
>>>>> *[Loaded sun.misc.Cleaner from
>>>>> /home/peter/Apps64/jdk1.8.0-ea-b121/jre/lib/rt.jar]*
>>>>> [Loaded java.io.ByteArrayInputStream from
>>>>> /home/peter/Apps64/jdk1.8.0-ea-b121/jre/lib/rt.jar]
>>>>> [Loaded sun.util.calendar.ZoneInfoFile$ZoneOffsetTransitionRule
>>>>> from /home/peter/Apps64/jdk1.8.0-ea-b121/jre/lib/rt.jar]
>>>>> ...
>>>>>
>>>>>
>>>>> I'm on linux, 64bit and using official EA build 121 of JDK 8...
>>>>>
>>>>> But if I try with JDK 7u45, I don't see it.
>>>>
>>>> So what changed between JDK 7 and JDK 8?
>>>>
>>>> I suspect the following: 8007572: Replace existing jdk timezone data
>>>> at <java.home>/lib/zi with JSR310's tzdb
>>>>
>>>>
>>>> Regards, Peter
>>>>
>>