RFR 9/8u: Print heap changes in phases that actually change heap

[Roman Kennke]

Am 10.05.2017 um 12:25 schrieb Aleksey Shipilev:
> Hi,
>
> I think it makes sense to print heap changes only for phases that change heap
> occupancy. This means demoting Init-UR, and promoting Conc Reset Bitmaps:
>
> diff -r 4ee5b7c8a8ac src/share/vm/gc/shenandoah/shenandoahConcurrentThread.cpp
> --- a/src/share/vm/gc/shenandoah/shenandoahConcurrentThread.cpp	Tue May 09
> 12:26:31 2017 +0200
> +++ b/src/share/vm/gc/shenandoah/shenandoahConcurrentThread.cpp	Wed May 10
> 12:24:22 2017 +0200
> @@ -244,7 +244,7 @@
>
>    {
> -    GCTraceTime(Info, gc) time("Concurrent reset bitmaps", gc_timer,
> GCCause::_no_gc);
> +    GCTraceTime(Info, gc) time("Concurrent reset bitmaps", gc_timer,
> GCCause::_no_gc, true);
>
> diff -r 4ee5b7c8a8ac src/share/vm/gc/shenandoah/vm_operations_shenandoah.cpp
> --- a/src/share/vm/gc/shenandoah/vm_operations_shenandoah.cpp	Tue May 09
> 12:26:31 2017 +0200
> +++ b/src/share/vm/gc/shenandoah/vm_operations_shenandoah.cpp	Wed May 10
> 12:24:22 2017 +0200
> @@ -147,7 +147,7 @@
>  void VM_ShenandoahInitUpdateRefs::doit() {
>    GCIdMark gc_id_mark(_gc_id);
>    ShenandoahHeap *sh = ShenandoahHeap::heap();
> -  GCTraceTime(Info, gc) time("Pause Init Update Refs", sh->gc_timer(),
> GCCause::_no_gc, true);
> +  GCTraceTime(Info, gc) time("Pause Init Update Refs", sh->gc_timer(),
> GCCause::_no_gc);
>
> Will look like this:
>
> [info][gc] GC(3) Pause Init Mark 0.481ms
> [info][gc] GC(3) Concurrent marking 3698M->3704M(4096M) 2.087ms
> [info][gc] GC(3) Pause Final Mark 3704M->182M(4096M) 1.778ms
> [info][gc] GC(3) Concurrent evacuation  184M->198M(4096M) 1.029ms
> [info][gc] GC(3) Pause Init Update Refs 0.019ms
> [info][gc] GC(3) Concurrent update references  200M->206M(4096M) 1.760ms
> [info][gc] GC(3) Pause Final Update Refs 206M->48M(4096M) 0.409ms
> [info][gc] GC(3) Concurrent reset bitmaps 48M->48M(4096M) 0.081ms
>
> The mirror patch goes to 8u.

Yep!