RFR: 8264524: jdk/internal/platform/docker/TestDockerMemoryMetrics.java fails due to OOM killed

[Jie Fu]

On Wed, 31 Mar 2021 17:14:32 GMT, Severin Gehwolf <sgehwolf at openjdk.org> wrote:

>> Hi all,
>> 
>> jdk/internal/platform/docker/TestDockerMemoryMetrics.java fails on some of our testing platforms.
>> This is because testMemoryFailCount [1] fails due to OOM killed.
>> This test fails to avoid OOM killed [2] if memory.failcnt is always 0.
>> 
>> The fix will print "Not OOM killed" if OOM killed doesn't happen.
>> And also fix another bug if the test get returned here [3].
>> 
>> Testing: 
>>   - jdk/internal/platform/docker/ hotspot/jtreg/containers on Linux/x64
>> 
>> Thanks.
>> Best regards,
>> Jie
>> 
>> [1] https://github.com/openjdk/jdk/blob/master/test/jdk/jdk/internal/platform/docker/TestDockerMemoryMetrics.java#L80
>> [2] https://github.com/openjdk/jdk/blob/master/test/jdk/jdk/internal/platform/docker/MetricsMemoryTester.java#L87
>> [3] https://github.com/openjdk/jdk/blob/master/test/jdk/jdk/internal/platform/docker/MetricsMemoryTester.java#L96
>
> test/jdk/jdk/internal/platform/docker/TestDockerMemoryMetrics.java line 120:
> 
>> 118:                 oa.shouldHaveExitValue(0).shouldContain("TEST PASSED!!!");
>> 119:             }
>> 120:         }
> 
> Consider a broken implementation of `Metrics.systemMetrics().getMemoryFailCount()`. Wouldn't the test now (falsely) pass?
> 
> What is the actual test output on those systems where the test fails? There should be a docker log file. Does it enter line 91?

Thanks @jerboaa for your review.

Test output when failing is just:
[failcount] 

It doesn't enter line 91 of test/jdk/jdk/internal/platform/docker/MetricsMemoryTester.java.


I assume memory.failcnt has been disabled on these platforms since it's always 0.
What about checking the value of memory.failcnt after testMemoryFailCount like:
// check after testMemoryFailCount()
if (memory.failcnt is zero) {
  // memory.failcnt has been disabled
  pass
} else {
  // a broken implementation of Metrics.systemMetrics().getMemoryFailCount()
  fail
}
Thanks.

-------------

PR: https://git.openjdk.java.net/jdk/pull/3286