RFR: Make heap counters update completely asynchronous

[Roman Kennke]

Am 21.09.2017 um 19:04 schrieb Aleksey Shipilev:
> On 09/21/2017 06:40 PM, Aleksey Shipilev wrote:
>> http://cr.openjdk.java.net/~shade/shenandoah/concthread-periodic/webrev.01/
>>
>> This uses the periodic tasks facility provided by VM to update the counters asynchronously.
>> Allocation and GC paths are triggering the update, but do not perform the update themselves. This
>> allows to simplify allocation path, capture GCLAB allocations without risking deadlocks, etc.
> Actually, let it be more resilient for the case WatcherThread crashes: there is some protection
> against that, but I think the failure would not be reliably reported. Capture that case in
> ShenandoahConcurrentThread itself after GC cycle.
>
> http://cr.openjdk.java.net/~shade/shenandoah/concthread-periodic/webrev.02/
>
> -Aleksey
>
yes