Re: RFR: 8218733: SA: CollectedHeap provides broken implementation for used() and capacity()

[Stefan Karlsson]

On 2019-02-11 10:39, Aleksey Shipilev wrote:

On 2/11/19 9:13 AM, Stefan Karlsson wrote:

Please review this patch to remove the broken implementation of CollectedHeap 
used() and capacity()
and instead force all GCs to provide their own implementations.

https://cr.openjdk.java.net/~stefank/8218733/webrev.01/

Looks good.

Thanks!

Could you verify that the implementation for Epsilon is correct? I also haven't 
implemented capacity
for Shenandoah, as the information isn't trivially available in the 
ShenandoahHeap SA class. Do you
want to fix it as part of this patch, or should I create a separate RFE for 
Shenandoah?

Epsilon change looks trivially correct.

For Shenandoah, I think this would suffice:

      @Override
      public long capacity() {
-       // FIXME
-       return 0;
+        return numOfRegions() * ShenandoahHeapRegion.regionSizeBytes();
      }

I'll incorporate that into the patch.

Thanks,
StefanK

-Aleksey