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

[Bob Vandette]

The Cpus_allowed_list need Linux 2.6.24 but that shouldn’t be a big problem.  We’ll only skip some
of the tests on older systems.  Not sure docker would run well on older kernels anyway.

Looks good,
Bob.

> On Nov 30, 2017, at 3:01 PM, mikhailo <mikhailo.seledtsov at oracle.com> wrote:
> 
> Bob, David,
> 
>   Thank you for review.
> 
>    Here is an updated webrev addressing your comments:
> 
>     http://cr.openjdk.java.net/~mseledtsov/8191943.02/
> 
> 
> Misha
> 
> 
> On 11/29/2017 09:28 PM, David Holmes wrote:
>> On 30/11/2017 10:08 AM, mikhailo wrote:
>>> Here is an updated webrev:
>>> 
>>>      http://cr.openjdk.java.net/~mseledtsov/8191943.01/
>> 
>> As Bob noted you may still need the guard here:
>> 
>>   55             testAPCCombo("0,1", 200*1000, 100*1000, 4*1024, 2);
>>   56             testAPCCombo("0,1", 200*1000, 100*1000, 1*1024, 2);
> I introduced a proper check for this.
>> 
>> though perhaps docker ignores invalid cpu-set values?
>> 
>> 161         Common.logNewTestCase("expectedAPC = " + expectedAPC);
>> 
>> That should still be a System.out.println - you already set the test case prior:
> I changed code to output both the original expected APC and the adjusted APC.
>> 
>> 155         Common.logNewTestCase("test cpu shares, shares = " + shares);
>> 
>> Having the same check duplicated three times is a bit messy, but not horrendously so. :)
> Introduced a common method to conditionally adjust APC.
> 
> Thank you,
> Misha
>> 
>> Thanks,
>> David
>> 
>>> 
>>> Misha
>>> 
>>> 
>>> On 11/29/2017 01:32 PM, mikhailo wrote:
>>>> 
>>>> 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
>>>>>>>> 
>>>> 
>>> 
>