hsx/hotspot-gc/hotspot: 8009536: G1: Apache Lucene hang during reference processing

[John Cuthbertson]

Hi Uwe,

Thanks for the update. That is good to know. The bulk of the credit goes 
to Bengt who did the initial diagnosis and the prototype fix.

Thanks also for walking me through how to reproduce the issue. Once the 
magic formula for the proxy was found - your instructions were spot on. 
The tests were awesome as marking stress tests and uncovered several 
issues associated with concurrent marking overflows. I've added them to 
the set of tests I run for marking changes. :)

Cheers,

JohnC

On 4/2/2013 12:16 PM, Uwe Schindler wrote:
> Hi John,
>
> today I installed JDK8 b83 on one of the Jenkins build servers used by Apache Lucene: The problem with 32 bit JVMs and G1 collector is solved. I compared the trunk checkout of Lucene with both JVMs: In b82 it hangs, in b83 it passes. So I was able to re-enable 32 bit builds without the extra workaround stacksize option again.
>
> Thanks for fixing this issue.
>
> Uwe
>
> -----
> Uwe Schindler
> uschindler at apache.org
> Apache Lucene PMC Member / Committer
> Bremen, Germany
> http://lucene.apache.org/
>
>> -----Original Message-----
>> From: hotspot-gc-dev-bounces at openjdk.java.net [mailto:hotspot-gc-dev-
>> bounces at openjdk.java.net] On Behalf Of john.cuthbertson at oracle.com
>> Sent: Tuesday, March 19, 2013 2:21 AM
>> To: hotspot-gc-dev at openjdk.java.net
>> Subject: hg: hsx/hotspot-gc/hotspot: 8009536: G1: Apache Lucene hang
>> during reference processing
>>
>> Changeset: fa08949fe0cb
>> Author:    johnc
>> Date:      2013-03-18 11:05 -0700
>> URL:       http://hg.openjdk.java.net/hsx/hotspot-
>> gc/hotspot/rev/fa08949fe0cb
>>
>> 8009536: G1: Apache Lucene hang during reference processing
>> Summary: In CMTask::do_marking_step(), Skip offering termination and
>> entering the first and second synchronization barriers if called from a serial
>> context, i.e. the VM thread.
>> Reviewed-by: brutisso, tschatzl
>>
>> ! src/share/vm/gc_implementation/g1/concurrentMark.cpp
>> ! src/share/vm/gc_implementation/g1/concurrentMark.hpp