RFR: 8131745: java/lang/management/ThreadMXBean/AllThreadIds.java still fails intermittently

[Daniil Titov]

Hi Alex and Serguei,

Please review a new version of the change [1] that makes sure that the test counts
only the threads it creates and ignores  Internal threads VM might create or  destroy.

Testing: Running this test in Mach5 with Graal on several hundred times ,
 tier1-tier3 tests  are in progress.

[1] http://cr.openjdk.java.net/~dtitov/8131745/webrev.02/ 
[2] https://bugs.openjdk.java.net/browse/JDK-8131745 

Thank you,
Daniil

On 5/22/20, 10:26 AM, "Alex Menkov" <alexey.menkov at oracle.com> wrote:

    Hi Daniil,

    I'm not sure all this retry logic is a good way.
    As mentioned in jira the most important part of the testing is ensuring 
    that you find all the created threads when they are alive, and you don't 
    find them when they are dead. The actual thread count checking is not 
    that important.
    I agree with this and I'd just simplify the test by removing checks for 
    thread count. VM may create and destroy internal threads when it needs it.

    --alex

    On 05/18/2020 10:31, Daniil Titov wrote:
    > Please review the change [1] that fixes an intermittent failure of the test.
    > 
    > This test creates and destroys a given number of daemon/user threads and validates the count of those started/stopped threads against values returned from ThreadMXBean thread counts.  The problem here is that if some internal threads is started ( e.g. " HotSpotGraalManagement Bean Registration"), or destroyed  (e.g. "JVMCI CompilerThread ") the test hangs waiting for expected number of live threads.
    > 
    > The fix limits the time the test is waiting for desired number of live threads and in case if this limit is exceeded the test repeats itself.
    > 
    > Testing. Test with Graal on and Mach5 tier1-tier7 test passed.
    > 
    > [1] http://cr.openjdk.java.net/~dtitov/8131745/webrev.01
    > [2] https://bugs.openjdk.java.net/browse/JDK-8131745
    > 
    > Thank you,
    > Daniil
    > 
    > 
    >