RFR(S): 8040807: G1: Enable G1CollectedHeap::stop()

[Per Liden]

Ping!

/Per

On 05/27/2014 01:15 PM, Per Liden wrote:
> Hi,
>
> I did some additional testing and eyeballing of this fix and noticed
> that it would be a good idea to also tell concurrent mark to abort,
> otherwise we will always wait until concurrent mark has finished, which
> is unnecessary (and could potentially take some time if the live set is
> large). So, I added a call to _cm->set_has_aborted() to abort any
> ongoing concurrent mark.
>
> Updated webrev:
> http://cr.openjdk.java.net/~pliden/8040807/webrev.1/
>
> Diff against previous webrev:
> http://cr.openjdk.java.net/~pliden/8040807/webrev.diff_0vs1/
>
> Testing:
> Wrote a simple test to provoke an concurrent mark followed by an
> immediate exit. With the first version of the patch, we would always
> wait until concurrent mark completes. Now it will instead show an
> concurrent-mark-abort, which happens much earlier.
>
> /Per
>
> On 05/22/2014 03:10 PM, Per Liden wrote:
>> Thanks Jon!
>>
>> /Per
>>
>> On 2014-05-20 16:45, Jon Masamitsu wrote:
>>> Looks good.
>>>
>>> Reviewed.
>>>
>>> Jon
>>>
>>> On 05/20/2014 04:59 AM, Per Liden wrote:
>>>> Looking for a couple of reviews in this patch.
>>>>
>>>> Summary: This patch re-enables the controlled stopping of G1's
>>>> concurrent threads at VM shutdown. This could potentially cause hangs
>>>> during VM shutdown because the G1 marking threads could get stuck in
>>>> various places and fail to terminate. JDK-8040803 and JDK-8040804
>>>> fixed these issues, so this is the final step to re-enable the actual
>>>> stopping of those threads. This patch also moves the call to
>>>> CollectedHeap::stop() a few lines down to group the GC related stuff
>>>> together. It also adjusts/removes some comments that are no longer
>>>> correct.
>>>>
>>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8040807
>>>> Webrev: http://cr.openjdk.java.net/~pliden/8040807/webrev.0/
>>>>
>>>> Testing:
>>>> - GC nightlies. 5 tests in this suite used to timeout because of the
>>>> issue with hanging threads. They now pass.
>>>> - JPRT
>>>>
>>>> Thanks!
>>>> /Per
>>>
>>
>