RFR 6963841: java/util/concurrent/Phaser/Basic.java fails intermittently

[Doug Lea]

On 04/02/12 07:28, David Holmes wrote:
> On 30/03/2012 9:22 PM, Chris Hegarty wrote:
>> Sorry guys, I think I found the actual cause for this failure. Though I
>> think the increased defensive timeouts are still a good idea.
>>
>> There is a race in the test itself. The "One thread interrupted" test
>> tries to interrupt a thread blocked in awaitAdvanceInterruptibly, but
>> how do we know the thread has actually made it to this point before we
>> interrupt? The usual situation with these kind of tests!
>
> I don't think we're meant to. The interrupt will remain pending and only cause
> the IE when it does reach awaitAdvanceInterruptibly. It is the thread doing the
> interrupting that needs to wait until the interrupt has been received - but I
> don't think it needs to re-interrupt as that implies the interrupt is being lost
> somewhere.

I think you are both right -- the main thread must delay but need not
re-interrupt.

-Doug


>
> David
>
>> The solution is to retry the interrupt if we know the target thread
>> hasn't thrown anything.
>>
>> http://cr.openjdk.java.net/~chegar/6963841/webrev.01/webrev/
>>
>> -Chris.
>>
>>
>> On 27/03/2012 11:58, Doug Lea wrote:
>>> On 03/26/12 23:04, Chris Hegarty wrote:
>>>> David, Doug,
>>>>
>>>> This test has been failing intermittently on jdk7u-dev and jdk8 for a
>>>> while now.
>>>> It only appears to fail when run in our internal build/test system
>>>> (JPRT).
>>>>
>>>> I believe the cause of the failure to be simply that the machines the
>>>> test is
>>>> run on are too slow, or very busy, and the defensive timeout in the
>>>> test are not
>>>> large enough to handle this. The solution is to increase these timeout
>>>> (similar
>>>> to other tests in the concurrency area that we increased the timeouts
>>>> for too).
>>>>
>>>
>>> OK. I synced with our version. As always, it is too bad that there is no
>>> way to operationalize the notion of "for some timeout value appropriate
>>> for the platform, no TimeoutExceptions occur".
>>>
>>> -Doug
>