RFR 8228720: Shenandoah: Implementation of concurrent class unloading

[Roman Kennke]

It looks good to me.

I wonder if we should just remove the ShUnloadClassesFrequency
altogether. Probably a good idea to do in a follow-up changeset.

Thanks!
Roman


> Updated Webrev: http://cr.openjdk.java.net/~zgu/JDK-8228720/webrev.01/
> 
> Moved GC argument setting and default class unloading frequency value
> from early concurrent nmethod changes to this changeset.
> 
> Reran hotspot_gc_shenandoah tests.
> 
> Thanks,
> 
> -Zhengyu
> 
> On 7/29/19 8:43 AM, Zhengyu Gu wrote:
>> Please review this implementation of Shenandoah concurrent class
>> unloading.
>>
>> This patch is built on top of concurrent nmethod evacuation and
>> disarming in early patch. It moves class unloading and nmethod
>> liveness check into concurrent evacuation phase.
>>
>>
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8228720
>> Webrev: http://cr.openjdk.java.net/~zgu/JDK-8228720/webrev.00/index.html
>>
>> Test:
>>    hotspot_gc_shenandoah (fastdebug and release) on Linux x86_64
>>    specjvm (fastdebug and release) on LInux x86_64.
>>
>> Thanks,
>>
>> -Zhengyu