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

[mikhailo]

Here is an updated webrev:

     http://cr.openjdk.java.net/~mseledtsov/8191943.01/


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
>>>>>
>