RFR 8160892: VM warning: WaitForMultipleObjects timed out

[David Holmes]

On 15/07/2016 8:57 AM, Ivan Gerasimov wrote:
> Hey!
>
> I've updated the webrev in place at
> http://cr.openjdk.java.net/~igerasim/8160892/01/webrev/

Thanks Ivan - looks good.

See also:

https://bugs.openjdk.java.net/browse/JDK-8160596
https://bugs.openjdk.java.net/browse/JDK-8079441

regarding strange exit code values being seen.

David

> On 15.07.2016 0:31, Daniel D. Daugherty wrote:
>> On 7/14/16 12:46 PM, Ivan Gerasimov wrote:
>>> Thank you David for looking into this!
>>>
>>> Here's the webrev updated in accordance with your and Daniel's
>>> suggestions:
>>> http://cr.openjdk.java.net/~igerasim/8160892/01/webrev/
>>
>> src/os/windows/vm/os_windows.cpp
>>     L3900:     bool registered = false;
>>         Please consider adding a comment above this variable:
>>
>>         // We only attempt to register threads until a process exiting
>>         // thread manages to set the process_exiting flag. Any threads
>>         // that come through here after the process_exiting flag is set
>>         // are unregistered and will be caught in the SuspendThread()
>>         // infinite loop below.
>>
> Sure.  Added this comment.
>
>>         My request is different than David's. I prefer the comment up
>>         here by the 'registered' variable because that variable is
>>         key for getting into the SuspendThread() infinite loop. The
>>         comment also occurs before all the code paths that you have
>>         trace out with the different Ept types and flags states.
>>
>> I'm really hoping that this is the last tweak we need to make to
>> clearly comment what we're doing to alleviate this OS race.
>> The number of occurrences of the underlying bug keep going down
>> with every iteration so we're getting close.
>>
> Yes.  This is my hope too.
>
> With kind regards,
> Ivan
>