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

[Bob Vandette]

I think you’ll  have problems on a single CPU box since the —cpuset-cpus argument to docker will most likely fail when 
you try to set it to “0,1”.

 55             testAPCCombo("0,1", 200*1000, 100*1000, 4*1024, 2);
 56             testAPCCombo("0,1", 200*1000, 100*1000, 1*1024, 2);

Bob.


> On Nov 29, 2017, at 7:08 PM, mikhailo <mikhailo.seledtsov at oracle.com> wrote:
> 
> 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
>>>>>> 
>> 
>