RFR(S): JDK-8148104 HSDB could not terminate when launched on CLI.

[Dmitry Samersoff]

Yuji,

I think both changes are good so I add this patch to webrev.

see:

http://cr.openjdk.java.net/~dsamersoff/sponsorship/kubota.yuji/JDK-8148104/webrev.02/

-Dmitry


On 2016-01-25 13:57, KUBOTA Yuji wrote:
> Hi Dmitry and Jaroslav,
> 
> 2016-01-25 18:11 GMT+09:00 Jaroslav Bachorik <jaroslav.bachorik at oracle.com>:
>> On 23.1.2016 12:13, Dmitry Samersoff wrote:
>>> Solution:
>>>
>>> Create frame before we initialize agent.
>>
>>
>> While this solution will work in this case I think it would be better to
>> daemonize the WorkerThread
>> (hotspot/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/utilities/WorkerThread.java)
>> - that should ensure that the application will be allowed to terminate even
>> though the worker thread is still running.
> 
> It's reasonable for me. I could not come up with the reason why the
> WorkerThread is not daemonized, so I wrote simply.
> I think that WorkerThread can be abandoned when JVM halts, so
> recreated the patch to demonize as below.
> 
> jdk9/hs-rt/hotspot (9982:91be2fb6db87)
> ----
> diff --git a/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/utilities/WorkerThread.java
> b/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/utilities/WorkerThread.java
> --- a/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/utilities/WorkerThread.java
> +++ b/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/utilities/WorkerThread.java
> @@ -35,7 +35,11 @@
>    public WorkerThread() {
>      mqb = new MessageQueueBackend();
>      mq = mqb.getFirstQueue();
> -    new Thread(new MainLoop()).start();
> +
> +    // Enable to terminate this worker during runnning by daemonize.
> +    Thread mqthread = new Thread(new MainLoop());
> +    mqthread.setDaemon(true);
> +    mqthread.start();
>    }
> 
>    /** Runs the given Runnable in the thread represented by this
> ----
> 
> Sorry, Dmitry, could you please re-upload this patch if you agree with
> this idea?
> 
> Thanks,
> Yuji
> 
>> -JB-
>>
>>>
>>> -Dmitry


-- 
Dmitry Samersoff
Oracle Java development team, Saint Petersburg, Russia
* I would love to change the world, but they won't give me the sources.