[TESTBUG] runtime/containers/docker/TestCPUAwareness.java failed in docker not supporting --cpus

Thu Jan 31 14:08:28 UTC 2019

Yes, that does provide a bit more unique testing so leave the change as you had it.

Thanks,
Bob.

> On Jan 28, 2019, at 8:41 PM, Ao Qi <aoqi at loongson.cn> wrote:
> 
> Hi Bob,
> 
> Thanks! I am not a containers expert and have one small question. The
> maximum amount of --cpus is 4 (equivalent to both setting —cpu-period
> and —cpu-quota) in the already existing test. Is it valuable to keep
> testCpus(i, i) according to the max num of available CPUs? If not, I
> would also prefer removing the lines. In addition, I think I forgot to
> update the copyright year, it will be fixed in the next version of
> wevrev.
> 
> On Mon, Jan 28, 2019 at 11:35 PM Bob Vandette <bob.vandette at oracle.com> wrote:
>> 
>> There is already a test that verifies —cpu-period and —cpu-quota.
>> I would just remove these lines.
>> 
>>  62             // leave one CPU for system and tools, otherwise this test may be unstable
>>  63             int maxNrOfAvailableCpus =  availableCPUs - 1;
>>  64             for (int i=1; i < maxNrOfAvailableCpus; i = i * 2) {
>>  65                 testCpus(i, i);
>>  66             }
>> 
>> 129     private static void testCpus(int valueToSet, int expectedTraceValue) throws Exception {
>> 130         Common.logNewTestCase("test cpus: " + valueToSet);
>> 131         DockerRunOptions opts = Common.newOpts(imageName)
>> 132             .addDockerOpts("--cpus", "" + valueToSet);
>> 133         Common.run(opts)
>> 134             .shouldMatch("active_processor_count.*" + expectedTraceValue);
>> 135     }
>> 
>> Bob.
>> 
>> On Jan 28, 2019, at 10:22 AM, Ao Qi <aoqi at loongson.cn> wrote:
>> 
>> Hi,
>> 
>> Since —cpus is a shortcut for of setting both --cpu-period and
>> --cpu-quota and the test is not intended to verify that docker works
>> correctly, I did not check the docker version and just replaced
>> setting --cpus with setting both --cpu-period and --cpu-quota. What do
>> you think of this patch:
>> http://cr.openjdk.java.net/~aoqi/8217597/webrev.01/ ?
>> 
>> Cheers,
>> Ao Qi
>> 
>> 
>> On Wed, Jan 23, 2019 at 11:37 PM Bob Vandette <bob.vandette at oracle.com> wrote:
>> 
>> 
>> Since —cpus is just a shortcut for of setting both --cpu-period and --cpu-quota”, I’d
>> be ok with removing this test.  The tests are intended to test the container/cgroup
>> configuration detection logic and not to verify that docker works correctly.
>> 
>> An alternate solution would be to add version detection to the Docker test check in
>> DockerTestUtils.java .   We already exec “docker ps” to see if docker is available
>> and enabled.
>> 
>> % docker --version
>> Docker version 17.03.1-ce, build 276fd32
>> 
>> 
>> Bob.
>> 
>> 
>> 
>> On Jan 22, 2019, at 10:19 PM, Ao Qi <aoqi at loongson.cn> wrote:
>> 
>> On Wed, Jan 23, 2019 at 10:55 AM David Holmes <david.holmes at oracle.com> wrote:
>> 
>> 
>> On 23/01/2019 11:58 am, Ao Qi wrote:
>> 
>> Hi David,
>> 
>> On Wed, Jan 23, 2019 at 5:24 AM David Holmes <david.holmes at oracle.com> wrote:
>> 
>> 
>> cc'ing Bob as our containers expert ...
>> 
>> On 23/01/2019 1:10 am, Ao Qi wrote:
>> 
>> Hi,
>> 
>> --cpus is available in Docker 1.13 and higher [1], so
>> runtime/containers/docker/TestCPUAwareness.java failed in docker which
>> does not support --cpus.
>> 
>> Webrev: http://cr.openjdk.java.net/~aoqi/docker/webrev.00/
>> 
>> This patch skips the test if --cpus is not supported. I tested
>> runtime/containers/docker/TestCPUAwareness.java on a Fedora 25 (Docker
>> version 1.12.6, build ae7d637/1.12.6, not supporting --cpus) and
>> Ubuntu 16.04 (Docker version 17.03.2-ce, build f5ec1e2, supporting
>> --cpus)
>> 
>> 
>> The patch causes the test to pass if launching Docker fails for any
>> reason so that is not good.
>> 
>> 
>> I tested two versions of docker which does not support --cpus. Their
>> exit values when using --cpus are 2 and 125, and outputs are:
>> 
>> flag provided but not defined: --cpus
>> See 'docker run --help'.
>> 
>> and
>> 
>> unknown flag: --cpus
>> See 'docker run --help'.
>> 
>> My initial thought was that the else condition of
>> "output.getExitValue() == 0" should match the condition of "--cpus not
>> supported". Firstly I used output.shouldMatch("docker run --help"),
>> but I am not sure if all the docker version behaves this way when
>> --cpus is not supported and "docker run --help" does not certainly
>> indicate "--cpus not supported", so I removed the else condition.
>> 
>> 
>> I think we need to try and find a way to clearly identifyt eh failing
>> condition. Is there are "docker --version" we coudl check?
>> 
>> 
>> I will do more research. Checking docker version may be one option,
>> and checking whether one option is support by docker may be also one
>> option. I will try them later, while waiting if there are some other
>> opinions :)
>> 
>> I am not sure if this is a testbug, so I did not file it on JBS. In
>> fact, I am not quite sure what kind of issue can be filed on JBS. Is
>> there any guidance document?
>> 
>> 
>> Any/all issues can be filed on JBS. You don't need to pre-classify as a
>> testbug, simple create an issue that a test is failing under specific
>> conditions. Whomever works on the bug will then determine whether it is
>> a testbug or product issue or something else. (We don't seem to have any
>> docs on using JBS ...)
>> 
>> 
>> What if the issue is not a bug or no body cares the issue? The issue
>> will be open on JBS forever?
>> 
>> 
>> Possibly :) But each component team performs regular triage of the bugs
>> that get filed and eventually things will be examined enough to see if
>> they are indeed a bug, and if not they will be closed as not an issue.
>> If a bug but low priority it may eventually get closed as "will not fix"
>> just to keep the open bug count down.
>> 
>> 
>> I was a little afraid that filing issues that are not bugs or nobody
>> cares would increase the workload of others and frustrate myself, so I
>> was not sure what kind of issue should be filed. Now I basically
>> clear, thanks David.
>> 
>> Cheers,
>> David
>> 
>> Thanks for your explanation, and I filed this issue on JBS:
>> https://bugs.openjdk.java.net/browse/JDK-8217597
>> 
>> In this case I'm not sure whether we require a docker version that
>> supports --cpus, and the test should be skipped otherwise. Though
>> ideally this would involve an explicit version check so we don't just
>> pass if the docker process fails.
>> 
>> Thanks,
>> David
>> 
>> 
>> 
>> Cheers,
>> Ao Qi
>> 
>> [1] https://docs.docker.com/config/containers/resource_constraints/#cpu
>> 
>> 
>> 