One area where D has the edge

[Laeeth Isharc via Digitalmars-d]

" If Java consumes 15% more power doing it, does
>> it matter on a PC? Most people don't dare. Does it matter for 
>> small-scale server environments? Maybe not. Does it matter 
>> when you deploy Hadoop on a 10,000 node cluster, and the 
>> holistic inefficiency (multiple things running concurrently) 
>> goes to 30%? Ask the people who sign the checks for the power 
>> bill. Unfortunately, inefficiency scales really well.
>
> No, Java does not consume 15% doing it, because there isn't 
> just one implementation of Java compilers.
>
> Most comercial JVMs do offer the capability of ahead of time 
> native code compilation or JIT caches.
>
> So when those 15% really matter, enterprises do shell out the 
> money for such JVMs.
>
> Oracle commercial JVM and the OpenJDK are just the reference 
> implementation.

Thanks for the colour.  (For clarity, the content from the link 
wasn't by me, and I meant the general gist rather than the 
details).  How do commercial JVMs rate in terms of memory usage 
against thoughtful native (D) code implementations?  Is the basic 
point mistaken?