JDK 9 RFR of JDK-8132548: java/lang/ThreadGroup/Stop.java fails with "RuntimeException: Failure"

[Martin Buchholz]

jdk/test/java/util/concurrent/tck has thousands of test methods.  It used
to take minutes to run them all, but now only takes 10 seconds, mostly due
to replacements of sleeps with faster and more robust alternatives, often
CountDownLatch.

On Fri, Jul 8, 2016 at 10:17 AM, joe darcy <joe.darcy at oracle.com> wrote:

> The most surefire way to make sure the test doesn't fail anymore is to hg
> rm the test; if and unless the code is actually removed, that would not be
> the most appropriate approach though ;-)
>
> While it might be overkill for this particular test, I think it would be
> preferable to start replacing our various sleep calls in tests with count
> down latches or other structures as appropriate. Converting this test could
> help provide a good example of the process.
>
> (As alluded to earlier, the test suite as a whole could be made to run
> somewhat faster. Tests which wait for seconds when the entire test could
> commonly run in milliseconds in many cases are proportionately a good
> candidate to speed up. The absolute wait time are also problematic on the
> other extreme, running under -Xint on a heavily loaded test system, "should
> never take this long" numbers often aren't enough.)
>
> Thanks,
>
> -Joe
>
> On 7/7/2016 11:46 PM, Amy Lu wrote:
>
> Yes, but I just thought that for a test that testing a deprecated (since
> 1.2) API, and failed with very very low frequency (actually, only one time
> during the years), we might not want to spend much effort on a big change,
> like rewrite with CountDownLatch :-)
>
>
> Thanks,
> Amy
>
> On 7/8/16 2:36 PM, Martin Buchholz wrote:
>
> CountDownLatch is a better way of waiting for events, like for the two
> threads to be started and for Thread.stop to have been called.
>
> The test should ensure that ThreadDeath is indeed thrown.  If the threads
> in the group notify the main thread via a latch when they catch
> ThreadDeath, then all the sleeps in this test can be removed.
>
> On Thu, Jul 7, 2016 at 11:01 PM, Amy Lu <amy.lu at oracle.com> wrote:
>
>> Thank you Joe for your review.
>>
>> The intent is to give it more chance "for the thread group stop to be
>> issued", not to extend the whole test execution timeout.
>>
>> I updated the webrev to make this in a retry, limit to 5 times of retry:
>> http://cr.openjdk.java.net/~amlu/8132548/webrev.01/
>>
>> Thanks,
>> Amy
>>
>>
>> On 7/8/16 12:15 PM, joe darcy wrote:
>>
>>> Hi Amy,
>>>
>>> I'm a bit uncomfortable with the fix as-is.
>>>
>>> Rather than hard-coding sleep values, if sleep values are needed I think
>>> it is a better practice to use ones that are scaled with the jtreg timeout
>>> factors, etc. used to run the tests. Please instead use something like the
>>> adjustTimeout method of
>>>
>>>     $JDK_FOREST_ROOT/test/lib/share/classes/jdk/test/lib/Utils
>>>
>>> As a general comment, I'd prefer we don't just up timeout values for
>>> tests. That can cause the whole test suite run to slow down, which is
>>> undesirable especially if the condition in question may actually be
>>> satisfied in many cases much faster than the timeout value.
>>>
>>> Thanks,
>>>
>>> -Joe
>>>
>>>
>>> On 7/7/2016 7:01 PM, Amy Lu wrote:
>>>
>>>> Please review this trivial fix for test:java/lang/ThreadGroup/Stop.java
>>>>
>>>> Though this is a test for a deprecated API, failed with very very low
>>>> frequency and hard to reproduce (I got no luck to reproduce it), I’d like
>>>> to patch it as suggested: extend the sleep in the main thread from one
>>>> second to five seconds. Also added 'volatile' to the boolean variable
>>>> 'groupStopped'.
>>>>
>>>> bug: https://bugs.openjdk.java.net/browse/JDK-8132548
>>>> webrev: http://cr.openjdk.java.net/~amlu/8132548/webrev.00/
>>>>
>>>> Thanks,
>>>> Amy
>>>>
>>>>
>>>> --- old/test/java/lang/ThreadGroup/Stop.java    2016-07-04
>>>> 14:53:59.000000000 +0800
>>>> +++ new/test/java/lang/ThreadGroup/Stop.java    2016-07-04
>>>> 14:53:58.000000000 +0800
>>>> @@ -1,5 +1,5 @@
>>>>  /*
>>>> - * Copyright (c) 1999, 2011, Oracle and/or its affiliates. All rights
>>>> reserved.
>>>> + * Copyright (c) 1999, 2016, Oracle and/or its affiliates. All rights
>>>> reserved.
>>>>   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
>>>>   *
>>>>   * This code is free software; you can redistribute it and/or modify it
>>>> @@ -29,7 +29,7 @@
>>>>   */
>>>>
>>>>  public class Stop implements Runnable {
>>>> -    private static boolean groupStopped = false ;
>>>> +    private static volatile boolean groupStopped = false ;
>>>>      private static final Object lock = new Object();
>>>>
>>>>      private static final ThreadGroup group = new ThreadGroup("");
>>>> @@ -70,7 +70,7 @@
>>>>              while (!groupStopped) {
>>>>                  lock.wait();
>>>>                  // Give the other thread a chance to stop
>>>> -                Thread.sleep(1000);
>>>> +                Thread.sleep(5000);
>>>>              }
>>>>          }
>>>>
>>>>
>>>>
>>>>
>>>
>>
>
>
>