RFR (S): Parallelize partial GC cleanup

[Aleksey Shipilev]

Ah! Oh!

http://cr.openjdk.java.net/~shade/shenandoah/partial-recycle-parallel/webrev.02/

Thanks,
-Aleksey

On 05/03/2017 04:20 PM, Zhengyu Gu wrote:
> 
> ShenandoahCollectionSet already has claim_next() to claim regions for parallel
> processing.
> 
> Thanks,
> 
> -Zhengyu
> 
> On 05/03/2017 10:12 AM, Aleksey Shipilev wrote:
>> Hi,
>>
>> Matrix and bitmap cleanups take significant time in partial GC. The obvious
>> solution is to parallelize it at this point, since we have mined out the
>> sequential improvements.
>>
>> Fix:
>>  
>> http://cr.openjdk.java.net/~shade/shenandoah/partial-recycle-parallel/webrev.01/
>>
>> Improves partial GC times significantly under heavy allocation pressure:
>>   http://cr.openjdk.java.net/~shade/shenandoah/partial-recycle-parallel/perf.txt
>>
>> Testing: hotspot_gc_shenandoah
>>
>> Thanks,
>> -Aleksey
>>