RFR(S): 8228960: [TESTBUG] containers/docker/TestJcmdWithSideCar.java: jcmd reports main class as 'Unknown'

[Mikhailo Seledtsov]

Hi Severin, Bob,

   Thank you for reviewing the code.

On 8/7/19, 11:38 AM, Bob Vandette wrote:
> Can’t you come up with a better way of synchronizing the test by possibly writing a
> file and waiting for it to exist with a timeout?
I will try out this approach.

Thanks,
Misha
> Isn’t there a shared volume between the two
> processes?
>
> We’ve been fighting test reliability for a while now.  I can only hope we’re getting
> to the end.
>
> Bob.
>
>> On Aug 7, 2019, at 2:18 PM, Severin Gehwolf<sgehwolf at redhat.com>  wrote:
>>
>> Hi Misha,
>>
>> On Tue, 2019-08-06 at 20:17 -0700, mikhailo.seledtsov at oracle.com wrote:
>>> Please review this change that fixes a container test TestJcmdWithSideCar.
>>>
>>> My investigation indicated that a root cause for this failure is:
>>> JCMD -l shows 'Unknown' for class name because the main class has not
>>> been loaded yet.
>>> The target test JVM has started, it is initializing, but has not loaded
>>> the main test class.
>> That's what I've found too.
>>
>>> The proposed solution is to try 'jcmd -l' several times, with a short
>>> sleep in between.
>> Thread.sleep() isn't great, but I'm not sure there is an alternative.
>>
>>> Also I have commented out the testCase02() due to another bug:
>>> "JDK-8228850: jhsdb jinfo fails with ClassCastException:
>>> s.j.h.oops.TypeArray cannot be cast to s.j.h.oops.Instance",
>>> which is not a test bug. IMO, it is better to run the test and skip a
>>> sub-case than to skip the entire test.
>>>
>>>      JBS: https://bugs.openjdk.java.net/browse/JDK-8228960
>>>      Webrev: http://cr.openjdk.java.net/~mseledtsov/8228960.00/
>> Looks OK to me.
>>
>> Thanks,
>> Severin
>>