RFR (S): Heap dump support

[Roman Kennke]

Hi Aleksey,

this would report evacuated objects twice, right? Maybe simply skip
cset regions?

Not sure we need to update references. Seems like extra unnecessary
work. Calling code should do the appropriate read barriers, or receive
opaque JNI handles.

I believe the straightforward way to implement this is to simply
delegate to marked_object_iterate() but only for non-cset regions.

Roman

Am Montag, den 12.12.2016, 12:17 +0100 schrieb Aleksey Shipilev:
> Hi,
> 
> I have been trying to analyze the cause for OOME with Shenandoah,
> only to figure
> that Shenandoah does not support heap dumping (d'oh).
> 
> Solved this by implementing ShenandoahHeap::safe_object_iterate:
>   http://cr.openjdk.java.net/~shade/shenandoah/heapdump-support/webre
> v.01/
> 
> Testing: manual heap dumps with fastdebug/release.
> 
> Thanks,
> -Aleksey
>