RFR(XS): 8191943: [TESTBUG] docker/TestCPUAwareness fails on machine with 2 CPUs

[mikhailo]

On 11/29/2017 01:29 PM, Bob Vandette wrote:
>> On Nov 29, 2017, at 4:10 PM, mikhailo <mikhailo.seledtsov at oracle.com> wrote:
>>
>> Hi Bob,
>>
>> The failure was caused by invoking this test case:
>>
>>      testCpuShares(4096, 4);
>>      The test case sets --cpu-shares to 4096, expects active processor count to be 4; ==> actual APC is 2.
> Ahh, that makes sense.  I thought docker was complaining due to the arguments being passed going
> beyond the available cpus.
>
>> Command:
>>
>>      docker run --tty=true --rm --cpu-shares=4096 jdk-internal:test-cpu /jdk/bin/java -Xlog:os+container=trace -version
>>
>> Detailed log is attached at:
>>
>> https://bugs.openjdk.java.net/secure/attachment/73820/test-case-failure-cpu-shares-4096.txt
>>
>>
>> Once I saw this issue, I decided to put limits on other test cases based on the number of processors available on a machine, just to be on a safe side.
>>
>> Perhaps a better approach here is to change the expected APC inside the testCpuShares() to be no greater than max number of available processors?
> Yes, the selection algorithm returns the smallest number of computed shares, quotas or active processors.  Using this approach, you’d actually be validating the algorithm more precisely.
OK. I will update the tests to do this kind of validation, and post a 
new webrev.


Misha
>
> Bob.
>
>
>>
>> Misha
>>
>>
>>
>>
>>
>>
>> On 11/29/2017 06:02 AM, Bob Vandette wrote:
>>> Misha,
>>>
>>> Which specific subtest failed on a 2 cpu system?
>>>
>>> I don’t see any subtests that should have failed.  You should be able
>>> to pass any quota, period and share value to docker independent of the
>>> number of CPUs.  testCpus and testAPCCombo don’t try to test more than 2 cpus.
>>>
>>> I’m ok with the change but just wondering why the guards are necessary.
>>>
>>> Bob.
>>>
>>>> On Nov 28, 2017, at 7:50 PM, mikhailo <mikhailo.seledtsov at oracle.com> wrote:
>>>>
>>>> Could you, please, review this simple fix? It limits test cases in TestCPUAwareness.java
>>>> based on the number of processors available.
>>>>
>>>>      JBS: https://bugs.openjdk.java.net/browse/JDK-8191943
>>>>      Webrev: http://cr.openjdk.java.net/~mseledtsov/8191943.00/
>>>>      Testing:
>>>>          1. Locally: exercised the affected test locally on Linux-x64
>>>>          2. Exercised the affected test on 2 processor machine
>>>>          3. Exercise the affected test via automated distributed test system
>>>>             In progress
>>>>
>>>> Misha
>>>>